tag:theconversation.com,2011:/au/topics/rainforests-1609/articlesRainforests – The Conversation2024-03-19T13:10:57Ztag:theconversation.com,2011:article/2239222024-03-19T13:10:57Z2024-03-19T13:10:57ZNigeria’s forests are fast disappearing – urgent steps are needed to protect their benefits to the economy and environment<p><em>Nigeria’s forest cover has been dwindling fast for decades. With one of the <a href="https://earth.org/challenges-facing-policies-against-deforestation-in-nigeria/">highest rates of deforestation</a> in the world, there are concerns about the survival of its forest resources. We asked forest management and biodiversity conservation expert Amusa Tajudeen to explain why the country’s forests are disappearing and what to do about it.</em></p>
<hr>
<h2>Which parts of Nigeria are covered by forest?</h2>
<p>Nigeria has a rain forest zone in the south. Forest cover decreases in density towards the north, where the savannah belt is characterised by grasses and sparse tree cover. The rain forest ecosystem <a href="https://collections.unu.edu/eserv/UNU:1726/unuinrapolicybriefvol2_4.pdf">lies</a> between latitudes 4⁰N and 9⁰N and extends from the coast to about 250km inland.</p>
<h2>What is the current status of Nigeria’s forest cover?</h2>
<p>Nigeria’s forest cover is diminishing in extent and quality. But reliable data is scarce. For instance, one record indicates that <a href="https://www.researchgate.net/profile/Thomas-Omali/publication/344238412_Prospects_of_satellite-Enhanced_Forest_Monitoring_for_Nigeria/links/5f5f7158299bf1d43c0223ce/Prospects-of-satellite-Enhanced-Forest-Monitoring-for-Nigeria.pdf#page=4">Nigeria’s land mass is 910,770km²</a> and forest occupies 110,890km², or 12.8% of the total land mass. Another shows that Nigeria’s land mass is 997,936km² and only <a href="https://www.ajol.info/index.php/jasr/article/view/112511">10% is under forest reserve</a>.</p>
<p>At independence in 1960, it was <a href="https://collections.unu.edu/eserv/UNU:1726/unuinrapolicybriefvol2_4.pdf">reported</a> that the colonial government had set aside 97,000km² (9.72%) of the country as forest reserves. </p>
<p>Historical accounts also indicate that the country’s rain forest, which was over 600,000km² in 1897 (60% of land mass), had <a href="https://bioone.org/journals/international-forestry-review/volume-8/issue-3/ifor.8.3.372/Status-of-Tropical-Forest-Management-2005-Summary-Report/10.1505/ifor.8.3.372.full?casa_token=ZTKPa_OhRG8AAAAA:iVodlrGMgTr3eYlu4CZ-IWR1KCxrg_0q6lnmCpc6zTfHRaBj2_kFYQETnMpHndwm6KRzxdefZXQ">reduced</a> by about half in 1960 to 30% of land mass. </p>
<p>Nigeria’s forests <a href="https://www.netjournals.org/pdf/NJAS/2015/1/15-011.pdf#page=1">covered</a> an estimated 175,000km² in 1990 and 135,000km² in 2000. Between 2000 and 2004, the country was said to have lost 55.7% of its primary forests – that is, 75,195km² of native and original forests that have never been logged and have developed under natural processes. </p>
<p>A report by the United Nations Collaborative Programme on Reducing Emissions from Deforestation and Forest Degradation in Developing Countries (UN-REDD) <a href="https://www.un-redd.org/partner-countries/africa/nigeria">shows</a> that the decline rate of forest cover in Nigeria ranged from 3.5% to 3.7% per annum over the period 2000 to 2010. This translates to a loss of 350,000–400,000 hectares of forest land yearly.</p>
<p>Unless something decisive is done, and urgently, the country will lose all its forest areas by the year 2052, if the prevailing rate of deforestation at 3.5% annually is anything to go by.</p>
<h2>Why is forest cover important?</h2>
<p>Forests are very important for the economic development of every nation. They also have environmental, ecological, socio-cultural, scientific and research service functions. </p>
<p>Forests provide numerous goods and services. Some are needed as raw materials – for example wood for building materials, fuel and paper. </p>
<p>Forests also offer natural foods and non-timber products like oilseeds, latexes, gums, resins, rattan, vanilla and game. Forest-based industries such as sawmills, paper mills and furniture industries provide employment and income. </p>
<p>Forest ecosystems offer physical, biological and chemical benefits. These include:</p>
<ul>
<li><p>conserving soil, controlling the timing and volume of water flows, protecting water quality and maintaining aquatic habitats </p></li>
<li><p>preventing disasters like floods and landslides, and moderating winds </p></li>
<li><p>conserving biodiversity </p></li>
<li><p>storing carbon, which mitigates climate change. </p></li>
</ul>
<p>The socio-cultural service functions of forests cover nature-based tourism and ecotourism activities. Ecotourism provides a means for people to use the forest without extracting its resources or degrading the environment. Wildlife attracts many visitors and foreign exchange earnings.</p>
<p>In addition, forests help to deepen our understanding of the natural world. Through research, we learn new things about species, habitats and ecosystems. Forest resources are particularly important in medicine, including immunology and other studies of diseases. </p>
<h2>Why is Nigeria’s forest cover being depleted?</h2>
<p>Before the 1950s, the forestry and agriculture sectors <a href="https://www.researchgate.net/profile/Paul-Owombo-2/publication/311869826_Contributions_of_Forestry_Sub-sector_to_the_Nigerian_Economy_A_Co-integration_Approach/links/5c3ef31692851c22a3789e6a/Contributions-of-Forestry-Sub-sector-to-the-Nigerian-Economy-A-Co-integration-Approach.pdf">contributed</a> over 80% of Nigeria’s gross domestic product. This changed after the discovery of oil in the 1950s and early 1960s.</p>
<p>Today, the laws and policies associated with forest administration are obsolete. In addition, supervision, monitoring and surveillance of forest areas is poor. Staffing and provision of basic infrastructure are grossly inadequate. </p>
<p>The principle of sustained yield forestry, when products removed from the forest are replaced by growth, has been abandoned in most forest reserves. Inventory records of resources are insufficient. Local people don’t participate enough in decision-making related to forests. The forestry sector is also affected by corruption, such as misappropriation of funds and <a href="http://repository.ui.edu.ng/handle/123456789/1405">illegal activities</a>.</p>
<p>In Nigeria, primary forests are <a href="http://repository.ui.edu.ng/handle/123456789/1405">cleared</a> extensively. The various state forestry departments have been unable to adequately protect the forest estate. Most forest reserves that were once managed for timber production have become deforested and fragmented. Many have been converted for other land uses. </p>
<p>Large scale agriculture has consumed a significant portion of forested areas. Similarly, <a href="https://digitalscholarship.tsu.edu/ajcjs/vol9/iss1/10/">unlawful and indiscriminate logging activities</a> take place in naturally occurring forests. </p>
<p>Urbanisation, which comes with roads, buildings and other infrastructure, is often carried out without proper planning. </p>
<h2>How can this depletion be tackled?</h2>
<p>Based on our <a href="http://80.240.30.238/bitstream/123456789/1405/1/%2816%29%20ui_inpro_amusa_forest_2017.pdf">studies</a> of the Nigerian forests over the years and <a href="https://www.rufford.org/projects/tajudeen-okekunle-amusa/strengthening-monitoring-systems-for-adaptive-management-and-protection-of-forest-elephants-in-omo-forest-reserve-southwestern-nigeria/">lessons</a> from numerous projects carried out, I have the following recommendations:</p>
<p>Most countries have a forestry law. Unfortunately Nigeria’s forest policy is not backed by a code or act. A national Forestry Act could reverse the decline in forest cover. It could give adequate protection and ensure sustainable management of the country’s forest estate.</p>
<p>There is an urgent need to plant and replant trees across the country. The various state governments can collaborate with non-governmental organisations to achieve this. </p>
<p>Reforestation involves replanting trees in areas where forests have been destroyed. Afforestation involves creating new forests on previously non-forested land. These campaigns should plant a diverse range of native tree species. </p>
<p>It’s also crucial to promote sustainable forestry practices. The government should enforce strict regulations against illegal logging and unsustainable timber harvesting. Enforcement can be done using technology such as remote sensors, drones and satellite imagery. It is essential to work with local communities, traditional leaders and NGOs to raise awareness about the importance of forest conservation.</p>
<p>Finally, there should be proper staffing. Adequately trained forest professionals and well equipped guards should be hired to safeguard the forests. Education and training programmes should teach local communities, forest workers and farmers about sustainable forestry methods and the importance of preserving biodiversity.</p><img src="https://counter.theconversation.com/content/223922/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Tajudeen Amusa does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Nigeria’s forest resources have dwindled and are in danger of disappearing in a few decades if nothing is done to save them.Tajudeen Amusa, Associate Professor, Forest Resources Management, University of IlorinLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2225992024-02-26T05:03:51Z2024-02-26T05:03:51ZSecrets in the canopy: scientists discover 8 striking new bee species in the Pacific<figure><img src="https://images.theconversation.com/files/577494/original/file-20240222-16-pcdtt5.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C4000%2C2000&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">James Dorey Photography</span></span></figcaption></figure><p>After a decade searching for new species of bees in forests of the Pacific Islands, all we had to do was look up. </p>
<p>We soon found <a href="https://www.frontiersin.org/articles/10.3389/fevo.2024.1339446/full">eight new species</a> of masked bees in the forest canopy: six in Fiji, one in French Polynesia and another in Micronesia. Now we expect to find many more. </p>
<p>Forest-dwelling bees evolved for thousands of years alongside native plants, and play unique and important roles in nature. Studying these species can help us better understand bee evolution, diversity and conservation.</p>
<p>Almost <a href="https://www.nature.com/articles/s41597-023-02626-w">21,000 bee species are known to science</a>. Many more remain undiscovered. But it’s a race against time, as the twin challenges of habitat loss and climate change threaten bee survival. We need to identify and protect bee species before they disappear forever.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/577774/original/file-20240225-24-qvx9ve.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A group of research students using stepping stones to cross a creek in the rainforest while carrying sampling nets on short poles" src="https://images.theconversation.com/files/577774/original/file-20240225-24-qvx9ve.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/577774/original/file-20240225-24-qvx9ve.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/577774/original/file-20240225-24-qvx9ve.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/577774/original/file-20240225-24-qvx9ve.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/577774/original/file-20240225-24-qvx9ve.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/577774/original/file-20240225-24-qvx9ve.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/577774/original/file-20240225-24-qvx9ve.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Searching for bees in the rainforest on Vanua Levu, formerly known as Sandalwood Island, the second largest island of Fiji.</span>
<span class="attribution"><span class="source">James Dorey Photography</span></span>
</figcaption>
</figure>
<h2>Introducing the new masked bees</h2>
<p><a href="https://onlinelibrary.wiley.com/doi/abs/10.1111/brv.12947">Pollinators abound in forests</a>. But scientific research has tended to focus on bees living closer to the ground.</p>
<p>We believe this sampling bias is replicated across much of the world. For example, another related Oceanic masked bee, <em>Pharohylaeus lactiferus</em> (a cloaked bee), was recently found in the canopy <a href="https://theconversation.com/phantom-of-the-forest-after-100-years-in-hiding-i-rediscovered-the-rare-cloaked-bee-in-australia-156026">after 100 years in hiding</a>. </p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/577776/original/file-20240225-30-ni8m63.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Closeup of one of the new masked bees showing the yellow markings on its face" src="https://images.theconversation.com/files/577776/original/file-20240225-30-ni8m63.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/577776/original/file-20240225-30-ni8m63.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=900&fit=crop&dpr=1 600w, https://images.theconversation.com/files/577776/original/file-20240225-30-ni8m63.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=900&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/577776/original/file-20240225-30-ni8m63.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=900&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/577776/original/file-20240225-30-ni8m63.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1131&fit=crop&dpr=1 754w, https://images.theconversation.com/files/577776/original/file-20240225-30-ni8m63.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1131&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/577776/original/file-20240225-30-ni8m63.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1131&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">This masked bee was collected from a canopy-flowering mistletoe near Mount Nadarivatu on Viti Levu, Fiji.</span>
<span class="attribution"><span class="source">James Dorey Photography</span></span>
</figcaption>
</figure>
<p>Our <a href="https://doi.org/10.11646/zootaxa.4674.1.1">first decade of bee sampling</a> in Fiji turned up only one bee from the genus <em>Hylaeus</em>. This bee probably belonged in the canopy so we were very lucky to catch it near the ground. Targeted attempts over the next few years, using our standard short insect nets, failed to find any more. </p>
<p>But this changed when we turned our attention to searching the forest canopy. </p>
<p>Sampling in the canopy is physically challenging. Strength and skill are required to sweep a long, heavy net and pole through the treetops. It’s quite a workout. We limit our efforts to the edges of forests, where branches won’t tangle the whole contraption.</p>
<p>By lifting our gaze in this way, we discovered eight new bee species, all in the genus <em>Hylaeus</em>. They are mostly black with stunning yellow or white highlights, especially on their faces – hence the name, masked bees. </p>
<p>They appear to rely exclusively on the forest canopy. This behaviour is striking and has rarely been identified in bees before (perhaps because few scientists have been looking for bees up there). </p>
<p>Because the new species live in forests and native tree tops, they’re likely to be vulnerable to land clearing, cyclones and climate change. </p>
<p>More work is needed to uncover the secrets hidden in these dense tropical treetops. It may require engineering solutions such as canopy cranes and drones, as well as skilful tree-climbing using ropes, pulleys and harnesses.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/move-over-honeybees-aussie-native-bees-steal-the-show-with-unique-social-and-foraging-behaviours-200536">Move over, honeybees: Aussie native bees steal the show with unique social and foraging behaviours</a>
</strong>
</em>
</p>
<hr>
<h2>Michener’s missing links</h2>
<p>The journey of bees across the Pacific region is a tale of great dispersals and isolation.</p>
<p>Almost 60 years ago, world-renowned bee expert <a href="https://catalogue.nla.gov.au/catalog/787658">Charles Michener described</a> what was probably the most isolated masked bee around, <em>Hylaeus tuamotuensis</em>. </p>
<figure class="align-left zoomable">
<a href="https://images.theconversation.com/files/577779/original/file-20240225-16-iay0de.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Searching for bees on Fiji’s highest peak, Mount Tomanivi, here two researchers are picking a path through dense undergrowth while carrying nets on short poles" src="https://images.theconversation.com/files/577779/original/file-20240225-16-iay0de.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/577779/original/file-20240225-16-iay0de.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=900&fit=crop&dpr=1 600w, https://images.theconversation.com/files/577779/original/file-20240225-16-iay0de.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=900&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/577779/original/file-20240225-16-iay0de.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=900&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/577779/original/file-20240225-16-iay0de.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1131&fit=crop&dpr=1 754w, https://images.theconversation.com/files/577779/original/file-20240225-16-iay0de.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1131&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/577779/original/file-20240225-16-iay0de.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1131&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Fiji’s highest peak, Mount Tomanivi, is home to unique bee species.</span>
<span class="attribution"><span class="source">James Dorey Photography</span></span>
</figcaption>
</figure>
<p>The specimen was found in French Polynesia. At the time, Michener said that was “entirely unexpected”, because the nearest relatives were, as the bee flies, 4,000km north in Hawaii, 5,000km southwest in New Zealand, and 6,000km west in Australia. </p>
<p>So how did it get there and where did it come from?</p>
<p>Our research helps to answer these questions. We found eight new <em>Hylaeus</em> species including one from French Polynesia. Using genetic analysis and other methods, we found strong links between these species and <em>H. tuamotuensis</em>. </p>
<p>So Michener’s bee was probably an ancient immigrant from Fiji, 3,000km away. A journey of that magnitude is no mean feat for bees smaller than a grain of rice.</p>
<p>Of course, there are <a href="https://geoscienceletters.springeropen.com/articles/10.1186/s40562-016-0041-8">more than 1,700 islands in the Pacific</a>, which can serve as stepping stones for bees on their long journeys. </p>
<p>We don’t yet know how many new <em>Hylaeus</em> species might exist in the South Pacific, or the routes they took to get to their island homes. But we suspect there are many more to be found.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/phantom-of-the-forest-after-100-years-in-hiding-i-rediscovered-the-rare-cloaked-bee-in-australia-156026">Phantom of the forest: after 100 years in hiding, I rediscovered the rare cloaked bee in Australia</a>
</strong>
</em>
</p>
<hr>
<h2>Our Pacific emissaries</h2>
<p>The early origins of Fijian bees – both <a href="https://doi.org/10.1080/03721426.2020.1740957">ground-dwelling <em>Homalictus</em></a> and <a href="https://doi.org/10.1016/j.ympev.2012.10.018">forest-loving <em>Hylaeus</em></a> – can be traced to the ancient past when Australia and New Guinea were part of one land mass, known as Sahul. The ancestors of both groups then undertook epic oceanic journeys to travel from Sahul to the furthest reaches of the Pacific, where they diversified. But the <em>Hylaeus</em> travelled furthest, by thousands of kilometres.</p>
<p>These little emissaries have similarly brought together researchers across the region. We resolved difficulties sampling and gathering knowledge by working with people across the Pacific, including Fiji, French Polynesia, and Hawaii. It shows what can be accomplished with international collaboration. </p>
<p>Together we are making great strides towards understanding our shared bee biodiversity. Such collaborations are our best chance of discovering and conserving species while we can.</p>
<p><em>We would like to thank Ben Parslow and Karl Magnacca for their contribution to this article. We would further like to thank our collaborators and their home institutions, the Hawiian Department of Land and Natural Resources, Muséum national d’Histoire naturelle, University of the South Pacific, the South Australian Museum and Adelaide University.</em></p><img src="https://counter.theconversation.com/content/222599/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>James B. Dorey has received funding for this work from The Playford Trust as a PhD and Honours scholarship recipient, Flinders University through the AJ and IM Naylon PhD Scholarship, and the Australian Government through the New Colombo Plan . He is affiliated with both Flinders University and the University of Wollongong.</span></em></p><p class="fine-print"><em><span>Amy-Marie Gilpin is affiliated with the School of Science and Hawkesbury Institute for the Environment, Western Sydney University. Funding to publish this work was in part provided by Western Sydney University. Amy-Marie is also a member of the IUCN Wild Bee Specialist Group Oceania. </span></em></p><p class="fine-print"><em><span>Olivia Davies does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>By lifting their gaze to the treetops rather than poking around on the ground, researchers discovered eight new species of masked bees.James B. Dorey, Lecturer in Biological Sciences, University of WollongongAmy-Marie Gilpin, Lecturer in Invertebrate Ecology, Western Sydney UniversityOlivia Davies, Flinders UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2118622023-08-24T18:02:24Z2023-08-24T18:02:24Z‘Worthless’ forest carbon offsets risk exacerbating climate change<p>In early 2023, the Guardian published an <a href="https://www.theguardian.com/environment/2023/jan/18/revealed-forest-carbon-offsets-biggest-provider-worthless-verra-aoe">article</a> suggesting that more than 90% of rainforest carbon offsets are worthless. These credits are essentially a promise to protect forests and can be bought as a way to “offset” emissions elsewhere. Verra, the largest certifier of these offset credits, said the claims were “<a href="https://www.theguardian.com/environment/2023/jan/18/revealed-forest-carbon-offsets-biggest-provider-worthless-verra-aoe">absolutely incorrect</a>” but the story still shook confidence in the <a href="https://www.ecosystemmarketplace.com/publications/state-of-the-voluntary-carbon-markets-2022/">billion-dollar market</a>. Soon after, Verra’s CEO <a href="https://www.theguardian.com/environment/2023/may/23/ceo-of-worlds-biggest-carbon-credit-provider-says-he-is-resigning">stood down</a>. </p>
<p>The claims in the Guardian article rested heavily on analysis which had been published as a <a href="https://arxiv.org/abs/2301.03354">preprint</a> (before peer review). Now the research has been fully peer-reviewed and is published in the journal <a href="https://www.science.org/doi/10.1126/science.ade3535">Science</a>. It shows unequivocally that many projects which have sold what are known as REDD+ (reducing emissions from deforestation and degradation) credits have failed to reduce deforestation.</p>
<p>REDD+ projects aim to slow deforestation (for example, by supporting farmers to change their practices). They quantify the carbon saved through reducing deforestation relative to what would have happened without the project, and sell these emission reductions as credits. </p>
<p>Such REDD+ credits are widely used to “offset” (that is, cancel out) emissions from companies (who may use them to make claims that their operations are carbon neutral) or by people concerned about their carbon footprint. For example, if you were planning to fly from London to New York you might consider buying REDD+ credits that promise to <a href="https://www.5dnetzero.co.uk/product-category/projects/?gclid=CjwKCAjwivemBhBhEiwAJxNWN7yHQYW7T0ZBW6L4oG-0vtLQwFZO8SivBe65xy6fIM7gQhjgCmgfNBoCMgkQAvD_BwE">conserve rainforest in the Congo Basin</a> (with added benefits for forest elephants and bonobos). Offsetting your return flight would appear to cost a very affordable <a href="https://www.5dnetzero.co.uk/product-category/projects/?gclid=CjwKCAjwivemBhBhEiwAJxNWN7yHQYW7T0ZBW6L4oG-0vtLQwFZO8SivBe65xy6fIM7gQhjgCmgfNBoCMgkQAvD_BwE">£16.44</a>.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/544557/original/file-20230824-27-1cya5y.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Smiling bonobo eats plant" src="https://images.theconversation.com/files/544557/original/file-20230824-27-1cya5y.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/544557/original/file-20230824-27-1cya5y.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/544557/original/file-20230824-27-1cya5y.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/544557/original/file-20230824-27-1cya5y.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/544557/original/file-20230824-27-1cya5y.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/544557/original/file-20230824-27-1cya5y.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/544557/original/file-20230824-27-1cya5y.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Benefits for bonobos?</span>
<span class="attribution"><span class="source">Wirestock Creators / shutterstock</span></span>
</figcaption>
</figure>
<p>However, while previous <a href="https://conbio.onlinelibrary.wiley.com/doi/full/10.1111/cobi.13970">analysis showed</a> that some REDD+ projects have contributed to slowing deforestation and forest degradation, the central finding from the new study is that many projects have slowed deforestation much less than they have claimed and, consequently, have <a href="https://www.science.org/doi/10.1126/science.adj6951">promised greater carbon savings</a> than they have delivered. So that guilt-free flight to New York probably isn’t carbon neutral after all.</p>
<p>The finding that many REDD+ carbon credits have not delivered forest conservation is extremely worrying to anyone who cares about the future of tropical forests. We spoke to Sven Wunder, a forest economist and a co-author of the new study. He told us that: “To tackle climate change, tropical deforestation must be stopped. Forests also matter for other reasons: losing forests will result in loss of species, and will affect regional rainfall patterns. Despite the evidence that REDD+ has not been delivering additional conservation, we cannot afford to give up.”</p>
<h2>Deforestation could simply move elsewhere</h2>
<p>Carbon credits also face other challenges, one of the biggest being “leakage” or displacement of deforestation. Leakage may occur because the people who were cutting down the forest simply relocate to a different area. Alternatively, demand for food or timber that was fuelling deforestation in one place may be met by deforestation elsewhere – perhaps on the other side of the world. Another problem is ensuring that the forests are protected in perpetuity so that reduced deforestation represents <a href="https://www.cambridge.org/engage/coe/article-details/64aed5749ea64cc167e7422d">permanent removal</a> of carbon from the atmosphere.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/544567/original/file-20230824-23-zkdg4d.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Tree stumps in deforested area" src="https://images.theconversation.com/files/544567/original/file-20230824-23-zkdg4d.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/544567/original/file-20230824-23-zkdg4d.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/544567/original/file-20230824-23-zkdg4d.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/544567/original/file-20230824-23-zkdg4d.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/544567/original/file-20230824-23-zkdg4d.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/544567/original/file-20230824-23-zkdg4d.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/544567/original/file-20230824-23-zkdg4d.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">For credits to be worthwhile, forests must be protected forever.</span>
<span class="attribution"><span class="source">Eleanor Warren-Thomas</span></span>
</figcaption>
</figure>
<p>Addressing these challenges is vital because selling carbon credits is an important source of finance for forest conservation. It is not too dramatic to say that unreliable REDD+ credits <a href="https://www.science.org/doi/10.1126/science.adh3426">directly threaten forests</a>. </p>
<p>However, this is an active research area and new approaches are increasingly available. Andrew Balmford is a professor of conservation science at the University of Cambridge who is actively developing methods to improve the credibility of forest carbon markets. He says the new study raises some important concerns but that more <a href="https://www.cambridge.org/engage/coe/article-details/6409c345cc600523a3e778ae">robust and transparent</a> methods have been developed. Deploying these new methods, he told us, is “an urgent priority”. </p>
<p>Change is also needed to how certification operates. At present, there are incentives for verifiers to inflate estimates of the amount of deforestation that would have happened without the project, and therefore the number of credits that can be issued. Sven Wunder explains: “We need to move beyond vested interest towards independent governance employing scientifically informed, cutting-edge methods.”</p>
<h2>Reasons to be cautious</h2>
<p>Even if these problems can be solved, there are still reasons to be cautious about the role of carbon offsets in combating climate change. First, there is the risk that offsetting actually increases emissions because people or companies <a href="https://onlinelibrary.wiley.com/doi/full/10.1002/bse.2785">might feel more comfortable</a> emitting carbon if they believe they can undo any damage by simply buying carbon credits. For this reason, <a href="https://vcmintegrity.org/wp-content/uploads/2023/06/VCMI-Claims-Code-of-Practice.pdf">some argue</a> that offsets must only ever be a last resort, after all non-essential emissions have been cut (the problem being of course: who decides which emissions are essential?). </p>
<p>Second, keeping warming within 2°C will require most deforestation to be stopped and major reductions in fossil fuel emissions. There is a limit to which one <a href="https://www.ipcc.ch/report/ar6/wg3/downloads/report/IPCC_AR6_WGIII_SPM.pdf">can be used</a> to balance out the other.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/544559/original/file-20230824-9071-xz9a9n.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Cows in pasture without forested mountain in background" src="https://images.theconversation.com/files/544559/original/file-20230824-9071-xz9a9n.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/544559/original/file-20230824-9071-xz9a9n.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/544559/original/file-20230824-9071-xz9a9n.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/544559/original/file-20230824-9071-xz9a9n.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/544559/original/file-20230824-9071-xz9a9n.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/544559/original/file-20230824-9071-xz9a9n.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/544559/original/file-20230824-9071-xz9a9n.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Cows in DR Congo: REDD+ projects mustn’t harm local farmers.</span>
<span class="attribution"><span class="source">Kiki Dohmeier / shutterstock</span></span>
</figcaption>
</figure>
<p>Finally, there are serious equity concerns with some forest carbon offsets. If forest conservation is achieved by stopping farmers in low-income countries from clearing land for agriculture, REDD+ may <a href="https://peerj.com/articles/5106/">exacerbate poverty</a>: your long haul flight would come at the expense of others being able to feed their families.</p>
<p>We don’t know how much it would cost to achieve genuinely additional offsets which avoid leakage and ensure equity but it is likely to be considerably more expensive than forest carbon credits currently sell for. A higher price would reduce the perception that offsetting is an easy option and should encourage more focus on reducing emissions.</p>
<p>So, should you buy those cheap forest carbon offsets when taking a flight? Unfortunately, there’s currently little evidence that doing so will really make your journey carbon neutral. If you want to contribute to tackling climate change, perhaps the only real option is to not take the flight.</p>
<hr>
<figure class="align-right ">
<img alt="Imagine weekly climate newsletter" src="https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=600&fit=crop&dpr=1 600w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=600&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=600&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=754&fit=crop&dpr=1 754w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=754&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=754&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption"></span>
</figcaption>
</figure>
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<hr><img src="https://counter.theconversation.com/content/211862/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Julia P G Jones receives funding from the UK Department for Environment, Food and Rural Affairs (Darwin Initiative). She has in the past been funded by the UK's Foreign, Commonwealth and Development Office, and the Natural Environment Research Council. </span></em></p><p class="fine-print"><em><span>Neal Hockley receives funding from the UK Department for Environment, Food and Rural Affairs (Darwin Initiative) and has received funding from the UK's Foreign, Commonwealth & Development Office (FCDO) and UK Research Councils.</span></em></p>We need to urgently reform the way forest conservation is measured and sold as a way to offset emissions.Julia P G Jones, Professor of Conservation Science, Bangor UniversityNeal Hockley, Senior Lecturer in Environmental Economics & Policy, Bangor UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1874642022-08-30T20:04:48Z2022-08-30T20:04:48ZThis spider-eating, nest-sharing bat was once safe from fire – until the Black Summer burnt its rainforests<figure><img src="https://images.theconversation.com/files/480222/original/file-20220822-53919-s9oqlt.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C6222%2C4179&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">George Madani</span>, <span class="license">Author provided</span></span></figcaption></figure><p><em>Am I not pretty enough? This article is part of <a href="https://theconversation.com/au/topics/am-i-not-pretty-enough-106740">The Conversation’s series</a> introducing you to unloved Australian animals that need our help.</em></p>
<p>Golden-tipped bats are peculiar creatures. By night, they hunt the understorey for orb-weaving spiders, plucking them carefully from their sticky webs. By day, they roost in excavated basements at the bottom of nests made by two rainforest birds. </p>
<p>Unfortunately, while their rainforest nests usually keep them safe from fire, our <a href="https://doi.org/10.7882/AZ.2022.031">new research</a> found that’s no longer guaranteed. Rainforests grow in areas normally unburnt by fires. But ahead of the 2019/2020 Black Summer of fire, many of these areas had <a href="https://www.abc.net.au/news/2020-02-19/australia-bushfires-how-heat-and-drought-created-a-tinderbox/11976134">dried out</a>, setting the stage for fires of <a href="https://www.nature.com/articles/s41558-020-0716-1">unprecedented size and intensity</a>. As a result, <a href="https://www.nature.com/articles/s41467-021-21266-5">large areas of rainforest</a> along the coasts of south-eastern Australia were badly burnt. </p>
<p>Our study confirms <a href="https://onlinelibrary.wiley.com/doi/10.1111/geb.13473">expert predictions</a> that rainforest-dependent golden-tipped bats would be hard hit. We found the fires caused a large reduction in suitable habitat. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/481706/original/file-20220830-12598-oyyx5c.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/481706/original/file-20220830-12598-oyyx5c.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/481706/original/file-20220830-12598-oyyx5c.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=345&fit=crop&dpr=1 600w, https://images.theconversation.com/files/481706/original/file-20220830-12598-oyyx5c.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=345&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/481706/original/file-20220830-12598-oyyx5c.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=345&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/481706/original/file-20220830-12598-oyyx5c.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=434&fit=crop&dpr=1 754w, https://images.theconversation.com/files/481706/original/file-20220830-12598-oyyx5c.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=434&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/481706/original/file-20220830-12598-oyyx5c.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=434&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">The golden-tipped bat, <em>Phoniscus papuensis</em></span>
<span class="attribution"><span class="source">George Madani</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<h2>Why is this rainforest bat so special?</h2>
<p>Like birds, Australia’s many <a href="https://www.ausbats.org.au">bat species</a> come in many different shapes and sizes. Some fly fast in open air while others fly slowly with great agility amongst cluttered vegetation. The delicate golden-tipped bat is a “clutter specialist”, hunting in the understorey and plucking its favourite orb-weaver spiders from their webs without getting caught. Its wings are optimised for slow, careful flight. </p>
<p>Amazingly, golden-tipped bats roost in chambers they dig out underneath the elaborate suspended nests of two birds, the yellow-throated scrubwren and brown gerygone. These birds make their nests in patches of moist vegetation, which infiltrates the dryer eucalypt forests along a network of gully lines, up and down Australia’s east coast.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/5-remarkable-stories-of-flora-and-fauna-in-the-aftermath-of-australias-horror-bushfire-season-155749">5 remarkable stories of flora and fauna in the aftermath of Australia’s horror bushfire season</a>
</strong>
</em>
</p>
<hr>
<p>The birds have the top bunk, and the tiny bats – all six grams of them – make room in the basement. The woolly, golden-coloured fur of the roosting bats matches their mossy bird-built homes.</p>
<p>These daytime rainforest refuges give these bats access to wet and dry forests, allowing them to forage more widely at night. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/479761/original/file-20220817-7861-7jubwc.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="bat roost in nest" src="https://images.theconversation.com/files/479761/original/file-20220817-7861-7jubwc.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/479761/original/file-20220817-7861-7jubwc.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=415&fit=crop&dpr=1 600w, https://images.theconversation.com/files/479761/original/file-20220817-7861-7jubwc.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=415&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/479761/original/file-20220817-7861-7jubwc.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=415&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/479761/original/file-20220817-7861-7jubwc.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=522&fit=crop&dpr=1 754w, https://images.theconversation.com/files/479761/original/file-20220817-7861-7jubwc.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=522&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/479761/original/file-20220817-7861-7jubwc.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=522&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">A cluster of golden-tipped bats roosting in a space they’ve dug out underneath a suspended nest of the yellow-throated scrubwren.</span>
<span class="attribution"><span class="source">Fiona Backhouse</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<h2>Why are fires such bad news in rainforests?</h2>
<p>Animals in fire-prone eucalypt forests have evolved <a href="https://theconversation.com/some-animals-have-excellent-tricks-to-evade-bushfire-but-flames-might-be-reaching-more-animals-naive-to-the-dangers-164894">mechanisms to cope</a> with bushfires. But rainforest plants and animals have not had to learn these tricks. In rainforests, fire is a rare and destructive event. </p>
<p>Fire events classified as <a href="https://besjournals.onlinelibrary.wiley.com/doi/10.1111/1365-2656.12451">extreme</a> occur infrequently (by definition) and we rarely have an opportunity to measure their impacts on forest wildlife. Climate change <a href="https://www.nature.com/articles/s41467-021-27225-4#Bib1">has been linked</a> to increasingly dangerous fire weather conditions and more frequent extreme-level megafires in south-eastern Australia. </p>
<p>To find out what this means, our <a href="https://protect-au.mimecast.com/s/BVS3CmO5rku1vr0GtG-xP7?domain=doi.org">study</a> measured the impact of the 2019/20 megafires on this bat. </p>
<h2>What did we do?</h2>
<p>A year after the fires, we set harp traps in rainforest sites ranging from badly burnt to entirely unburnt. Our goal was to understand if golden-tipped bats occurred at each site and to use these data to model the effects of the fire on habitat for this species.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/480164/original/file-20220820-37908-9t0pw.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/480164/original/file-20220820-37908-9t0pw.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=401&fit=crop&dpr=1 600w, https://images.theconversation.com/files/480164/original/file-20220820-37908-9t0pw.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=401&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/480164/original/file-20220820-37908-9t0pw.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=401&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/480164/original/file-20220820-37908-9t0pw.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=504&fit=crop&dpr=1 754w, https://images.theconversation.com/files/480164/original/file-20220820-37908-9t0pw.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=504&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/480164/original/file-20220820-37908-9t0pw.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=504&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">We set these harp traps to catch golden-tipped bats at unburnt (left) and burnt (right) sites.</span>
<span class="attribution"><span class="source">Author provided</span></span>
</figcaption>
</figure>
<p>The result? At sites where high intensity fire had raged, we found <a href="https://zslpublications.onlinelibrary.wiley.com/doi/10.1111/acv.12805">modelled occupancy</a> fell sharply from 90% to 20%. Even a year later, badly burnt rainforest was no longer used by this species. </p>
<p>At burnt sites there were also few scrubwrens and gerygones, and almost none of their nests. On the plus side, in unburnt rainforest, we captured 66 golden-tipped bats, showing this elusive and poorly studied species persists in reasonable numbers. </p>
<p>We attached tiny radio-transmitters to our captured bats to see how they moved and <a href="https://onlinelibrary.wiley.com/doi/10.1111/aec.13229">roosted</a> in fire-affected habitat. Tracking bats across steep gullies of thick bush was hard work, as they moved almost daily to new roosts. </p>
<p>The bats chose their roosts in unburnt patches, which wasn’t surprising given that their preferred bird nests were readily consumed by fire. Their avoidance of burnt areas could suggest movements will be limited across fire-affected landscapes.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/480165/original/file-20220820-1413-29fv3z.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/480165/original/file-20220820-1413-29fv3z.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=417&fit=crop&dpr=1 600w, https://images.theconversation.com/files/480165/original/file-20220820-1413-29fv3z.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=417&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/480165/original/file-20220820-1413-29fv3z.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=417&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/480165/original/file-20220820-1413-29fv3z.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=524&fit=crop&dpr=1 754w, https://images.theconversation.com/files/480165/original/file-20220820-1413-29fv3z.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=524&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/480165/original/file-20220820-1413-29fv3z.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=524&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Golden-tipped bats showed a strong preference for roosting in unburnt locations. In this figure, bat roosts (blue triangles) and trap sites (yellow dots) are shown against mapped fire impacts at one study area.</span>
</figcaption>
</figure>
<p>Our study also tested whether a humble mop head could act as a stop-gap roost for these bats until the scrubwrens and gerygones could return and build new nests. </p>
<p>Why mops? Because these bats have previously been found roosting in an old mop head. </p>
<p>So far, we haven’t recorded them making use of the mops but we will continue to monitor them over the coming breeding season. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/480178/original/file-20220821-1373-jf35lu.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/480178/original/file-20220821-1373-jf35lu.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=800&fit=crop&dpr=1 600w, https://images.theconversation.com/files/480178/original/file-20220821-1373-jf35lu.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=800&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/480178/original/file-20220821-1373-jf35lu.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=800&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/480178/original/file-20220821-1373-jf35lu.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1005&fit=crop&dpr=1 754w, https://images.theconversation.com/files/480178/original/file-20220821-1373-jf35lu.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1005&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/480178/original/file-20220821-1373-jf35lu.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1005&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Mop heads were tested as artificial roosting habitat for golden-tipped bats.</span>
</figcaption>
</figure>
<h2>What happens if extreme fires become common?</h2>
<p>In many dry eucalypt forests, corridors of rainforest following gullies and creeks offer vital food and shelter for wildlife like the golden-tipped bat, significantly increasing local biodiversity.</p>
<p>Climate change poses a threat to rainforest-dependent wildlife in south-eastern Australia, by drying out soils, intensifying drought and increasing severe fire weather. Combined, these make it possible for unburnt rainforest to go up in flames. </p>
<p>Animals that rely on rainforests are not adapted to cope with fire. Increases in frequency of extreme fire events as the world warms will cause major disruption to the forests of south-eastern Australia.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/eYUQ2ahJlT4?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">These unusual golden-tipped bats roost underneath the hanging nests of two rainforest birds. Video by Lachlan Hall and George Madani.</span></figcaption>
</figure>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/a-staggering-1-8-million-hectares-burned-in-high-severity-fires-during-australias-black-summer-157883">A staggering 1.8 million hectares burned in 'high-severity' fires during Australia's Black Summer</a>
</strong>
</em>
</p>
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<p><em>George Madani and Anna Lloyd contributed to this research.</em></p><img src="https://counter.theconversation.com/content/187464/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Christopher Turbill received funding for this project from Australian Government’s Wildlife and Habitat Bushfire Recovery Program, and receives funding from the Australian Research Council, the Department of Agriculture, Water and the Environment, and the Department of Planning and Environment.</span></em></p><p class="fine-print"><em><span>Brad Law receives funding from the Commonwealth and New South Wales governments.</span></em></p>The tiny golden-tipped bat roosts in the nests of rainforest birds. But high intensity extreme fires can increasingly reach into their unburnt sanctuaries.Christopher Turbill, Senior Lecturer in Animal Ecology, Western Sydney UniversityBrad Law, Principal Research Scientist at NSW Primary Industries and Adjunct Fellow, Queensland University of TechnologyLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1832152022-05-18T21:59:51Z2022-05-18T21:59:51ZClimate change is killing trees in Queensland’s tropical rainforests<figure><img src="https://images.theconversation.com/files/463497/original/file-20220517-14-2jyrg.jpeg?ixlib=rb-1.1.0&rect=0%2C8%2C3000%2C2236&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">Alexander Schenkin</span>, <span class="license">Author provided</span></span></figcaption></figure><p>In recent years, the Great Barrier Reef off Australia’s northeast coast has seen multiple events of mass coral bleaching as human-caused global warming has driven sustained high temperatures in the ocean. </p>
<p>Alongside the Coral Sea is another spectacular natural wonder: the rainforests of the World Heritage-listed <a href="https://www.awe.gov.au/parks-heritage/heritage/places/world/wet-tropics">wet tropics of Queensland</a>. </p>
<p>It turns out the same climate change forces contributing to coral bleaching have also taken a toll on the trees that inhabit these majestic tropical rainforests. </p>
<p>In new research, we and our co-authors found that <a href="https://www.nature.com/articles/s41586-022-04737-7">mortality rates among these trees have doubled</a> since the mid 1980s, most likely due to warmer air with greater drying power. Like coral reefs, these trees provide essential structure, energy and nutrients to their diverse and celebrated ecosystems.</p>
<h2>A 50-year record</h2>
<p>Our study was based on 20 plots of trees in rainforests in northeast Queensland, which were created and monitored in a project begun in 1971 by a forest scientist named Geoff Stocker. </p>
<p>These plots were later incorporated into the Wet Tropics of Queensland World Heritage Area, and the monitoring has been carried on by CSIRO scientists based in Atherton, Queensland. </p>
<p>The plots are typically half a hectare (5,000m²) in size. In each plot the species and diameter of all trees larger than 10cm diameter at breast height were recorded.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/463500/original/file-20220517-18-tte281.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A photograph showing a hilly landscape covered in forests." src="https://images.theconversation.com/files/463500/original/file-20220517-18-tte281.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/463500/original/file-20220517-18-tte281.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/463500/original/file-20220517-18-tte281.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/463500/original/file-20220517-18-tte281.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/463500/original/file-20220517-18-tte281.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/463500/original/file-20220517-18-tte281.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/463500/original/file-20220517-18-tte281.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">A 50-year study revealed tree deaths are on the rise in the tropical forests of Queensland.</span>
<span class="attribution"><span class="source">Alexander Schenkin</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>The plots were revisited at intervals ranging from two to about five years. Tree diameters were recorded again, along with any new trees that had grown into the 10+cm size class, and any trees that had died.</p>
<p>Over the years, a few additional plots were initiated and contributed to our analyses. But these 20 provided a uniquely long record and formed the core of the dataset. </p>
<h2>The lifespan of trees</h2>
<p>With many plots visited multiple times, and many tree species on each plot, we were able to estimate the average percentage of trees in each species that died in a given year (the “annual mortality rate”). We also examined how this rate has changed over time. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/trees-arent-a-climate-change-cure-all-2-new-studies-on-the-life-and-death-of-trees-in-a-warming-world-show-why-182944">Trees aren't a climate change cure-all – 2 new studies on the life and death of trees in a warming world show why</a>
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<hr>
<p>Until about the mid 1980s, the average annual mortality rate was around 1%. This means that any given year, each tree had about a one in 100 chance of dying. </p>
<p>This corresponds to an average tree lifespan of about 100 years. </p>
<p>However, beginning in the mid-1980s, the annual mortality rate began to increase. By the end of our dataset in 2019, the average annual mortality rate had doubled to 2%. </p>
<p>These results match <a href="https://onlinelibrary.wiley.com/doi/epdf/10.1111/j.1654-1103.2009.01044.x">a similar pattern in tree deaths</a> in the Amazon rainforest at the same time, which suggests the increase in tropical tree mortality may be widespread.</p>
<p>A doubled annual mortality rate means that trees are only living half as long as they were, which means they are only storing carbon for half as long. </p>
<p>If the trend we observed is indicative of tropical forests in general, this could have big implications for the capacity of tropical forests to absorb and mitigate carbon dioxide emissions from human activity. </p>
<h2>Thirsty air</h2>
<p>What caused the increasing mortality rates of the tropical trees? </p>
<p>A first guess might be temperature stress: the average air temperature of the plots has increased in recent decades. </p>
<p>However, we did not find that temperature directly caused the increasing mortality rates. Instead the mortality rates correlated better with the drying power or “thirstiness” of the air, which scientists call the “air vapour pressure deficit”.</p>
<p>You’re probably familiar with the idea of relative humidity. It tells you how much water vapour there is in the air, as a percentage of the maximum amount the air can hold. </p>
<figure class="align-center ">
<img alt="An aerial photograph looking down on a forest from above." src="https://images.theconversation.com/files/463501/original/file-20220517-12-3ctw12.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/463501/original/file-20220517-12-3ctw12.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/463501/original/file-20220517-12-3ctw12.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/463501/original/file-20220517-12-3ctw12.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/463501/original/file-20220517-12-3ctw12.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/463501/original/file-20220517-12-3ctw12.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/463501/original/file-20220517-12-3ctw12.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Climate change is making the air ‘thirstier’, taking more water from trees by evaporation.</span>
<span class="attribution"><span class="source">Alexander Schenkin</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>When temperatures rise, the air’s capacity to hold water vapour increases exponentially. Each degree of warming lets the air hold about 7% more water vapour.</p>
<p>So if the air temperature increases, and the relative humidity stays the same, the air will have a bigger capacity to take on more water vapour. </p>
<p>To a first approximation, this is what has happened with global warming. Air temperature has increased, relative humidity has remained approximately constant, and the air has become thirstier. </p>
<p>This means the drying power of the atmosphere (or “evaporative demand”) has increased. This is what we found best explained the increasing mortality rates in Australian tropical trees. </p>
<h2>What’s next</h2>
<p>If greenhouse gas emissions continue unabated, both the air temperature and the air vapour pressure deficit will continue to increase. Our results suggest that in all likelihood this will cause a further acceleration in the increasing mortality rates of tropical rainforest trees. </p>
<p>Like coral reefs, tropical rainforests may then experience relatively rapid changes in species composition, biodiversity, and three-dimensional structure, threatening these prized Australian ecosystems as we know them. The best way to mitigate this threat is to urgently reduce emissions of carbon dioxide and other greenhouse gases, in order to slow global warming and eventually stabilise the global climate system. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/friday-essay-trees-have-many-stories-to-tell-is-this-our-last-chance-to-read-them-161428">Friday essay: trees have many stories to tell. Is this our last chance to read them?</a>
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</em>
</p>
<hr>
<img src="https://counter.theconversation.com/content/183215/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Lucas Cernusak receives funding from the Australian Research Council. </span></em></p><p class="fine-print"><em><span>Susan Laurance receives funding from Australian Research Council.</span></em></p>A 50-year experiment shows warmer, ‘thirstier’ air may have cut the lifespan of Queensland’s tropical trees in half since the 1980s.Lucas Cernusak, Associate professor, James Cook UniversitySusan Laurance, Professor, James Cook UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1762532022-03-16T19:26:41Z2022-03-16T19:26:41ZTo get to the rainforest canopy, it helps to have a crane<figure><img src="https://images.theconversation.com/files/452356/original/file-20220316-19-bngoib.jpeg?ixlib=rb-1.1.0&rect=6%2C0%2C4083%2C2728&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Johan Larson</span> <span class="attribution"><span class="license">Author provided</span></span></figcaption></figure><p>When you walk through a rainforest, you might feel like you’re missing out. You can hear birdsong and insect noises from way up high. For decades, the rainforest canopy was called “the last biotic frontier,” due to the sheer difficulty of getting up there. </p>
<p>Just over 30 years ago, that began to change. Researchers from the Smithsonian installed an industrial crane in a Panama rainforest to give scientists access. Ten more were installed around the world over the next decade. </p>
<p>In 1998, Australia joined in, building a canopy crane in the Daintree rainforest, near Cape Tribulation. Our <a href="https://doi.org/10.53060/prsq.2021.6">new research</a> covers the story of how the canopy crane was installed, and what research has stemmed from it. </p>
<p>While canopies are hard to access, they are well worth the effort. The tree canopy is where the atmosphere meets the biosphere. As much as half of all biodiversity on Earth is found in tropical rainforests – and a large proportion of all these species are found in the canopy. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/452371/original/file-20220316-17-1f7cljs.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="canopy crane" src="https://images.theconversation.com/files/452371/original/file-20220316-17-1f7cljs.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/452371/original/file-20220316-17-1f7cljs.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=396&fit=crop&dpr=1 600w, https://images.theconversation.com/files/452371/original/file-20220316-17-1f7cljs.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=396&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/452371/original/file-20220316-17-1f7cljs.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=396&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/452371/original/file-20220316-17-1f7cljs.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=498&fit=crop&dpr=1 754w, https://images.theconversation.com/files/452371/original/file-20220316-17-1f7cljs.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=498&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/452371/original/file-20220316-17-1f7cljs.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=498&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">The Daintree’s canopy crane is Australia’s first.</span>
<span class="attribution"><span class="license">Author provided</span></span>
</figcaption>
</figure>
<h2>What’s it like riding a canopy crane?</h2>
<p>Riding the crane is an eerily quiet experience, as the power driving the crane comes from offsite. </p>
<p>You step into a kind of dangling gondola, suspended from the rig of the crane. As you go up, you immediately notice how uneven the canopy is. The crowns of some trees are way higher than others. Some trees are covered in vines and epiphyte air plants. Birds and large insects are abundant, particularly around trees in flower. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/tiny-treetop-flowers-foster-incredible-beetle-biodiversity-150924">Tiny treetop flowers foster incredible beetle biodiversity</a>
</strong>
</em>
</p>
<hr>
<p>The tower crane is 45 metres tall. But even if you’re not great with heights, you may well find yourself too distracted by the sights to be worried. With a 55 metre jib, the crane can pivot to cover an area of forest larger than the size of a soccer field, with more than 80 species of trees. </p>
<p>The canopy crane is nestled so deeply in World Heritage-listed rainforest it can be hard to imagine the mammoth task involved in building a 70-tonne steel crane in the middle of the forest. In a serendipitous twist to the story, a heavy lift helicopter was available right when the crane was being erected, with the effort <a href="https://nqheritage.jcu.edu.au/850">captured on film</a>. </p>
<p>Funded by the Australian Research Council, the crane forms a key part of a nationally unique research and teaching facility at the Daintree Rainforest Observatory, where school and university students can stay for extended periods. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/452362/original/file-20220316-27-10om19r.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Rainforest canopy from the air" src="https://images.theconversation.com/files/452362/original/file-20220316-27-10om19r.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/452362/original/file-20220316-27-10om19r.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/452362/original/file-20220316-27-10om19r.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/452362/original/file-20220316-27-10om19r.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/452362/original/file-20220316-27-10om19r.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/452362/original/file-20220316-27-10om19r.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/452362/original/file-20220316-27-10om19r.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">A view not often seen: the Daintree rainforest canopy from above.</span>
<span class="attribution"><span class="license">Author provided</span></span>
</figcaption>
</figure>
<h2>What knowledge has the crane unlocked?</h2>
<p>Over the past 24 years, this industrious workhorse has made possible more than 120 studies across fields as varied as entomology, plant phenology and physiology. </p>
<figure class="align-left zoomable">
<a href="https://images.theconversation.com/files/452364/original/file-20220316-25-1lpht6k.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Canopy crane gondola" src="https://images.theconversation.com/files/452364/original/file-20220316-25-1lpht6k.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/452364/original/file-20220316-25-1lpht6k.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=900&fit=crop&dpr=1 600w, https://images.theconversation.com/files/452364/original/file-20220316-25-1lpht6k.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=900&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/452364/original/file-20220316-25-1lpht6k.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=900&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/452364/original/file-20220316-25-1lpht6k.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1131&fit=crop&dpr=1 754w, https://images.theconversation.com/files/452364/original/file-20220316-25-1lpht6k.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1131&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/452364/original/file-20220316-25-1lpht6k.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1131&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Researchers examine the canopy.</span>
<span class="attribution"><span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>One <a href="https://www.jstor.org/stable/3548119">important discovery</a> has been the influence on ant communities by honeydew produced by bugs as well as nectar exuded from a plant’s glands other than flowers. Some ant species specialise in extracting these high energy foods to become the dominant species in the canopy.</p>
<p>Not only that, but studies from the crane have shown us our assumptions that rainforest canopies are unusually rich in species may not be entirely correct. It has allowed us to test <a href="https://repository.si.edu/handle/10088/4383">the theory</a> two thirds of all insect species are found in the canopy. In fact, intensive <a href="https://doi.org/10.1098/rspb.2006.3521">sampling of beetles</a> showed both canopy and ground habitats are equally important for this hugely species rich group.</p>
<h2>What will reduced rainfall mean for the Daintree?</h2>
<p>Australia’s canopy crane has given us a bird’s eye view of how rainforests cope with a drying climate and drought conditions, with a large scale experiment <a href="https://doi.org/10.1002/ece3.4601">under way</a>. </p>
<p>Our Daintree experiment consists of two large areas covered by clear plastic roof panels which prevent almost all the rain from reaching the ground. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/high-value-opportunities-exist-to-restore-tropical-rainforests-around-the-world-heres-how-we-mapped-them-119508">High-value opportunities exist to restore tropical rainforests around the world – here's how we mapped them</a>
</strong>
</em>
</p>
<hr>
<p>Researchers monitor what occurs in these areas. With much less rain, plant productivity drops. Plants change the way their wood grows to cope with lower water availability. </p>
<p>When shrubs and saplings in the understorey are water-stressed, we see reduced rates of photosynthesis occuring alongside higher levels of insect attack on leaves. Wood-boring insects are more common on these saplings, while termites were more active across the drought experiment area. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/452367/original/file-20220316-21-8v92uv.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="plastic sheets over rainforest" src="https://images.theconversation.com/files/452367/original/file-20220316-21-8v92uv.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/452367/original/file-20220316-21-8v92uv.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=399&fit=crop&dpr=1 600w, https://images.theconversation.com/files/452367/original/file-20220316-21-8v92uv.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=399&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/452367/original/file-20220316-21-8v92uv.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=399&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/452367/original/file-20220316-21-8v92uv.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=501&fit=crop&dpr=1 754w, https://images.theconversation.com/files/452367/original/file-20220316-21-8v92uv.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=501&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/452367/original/file-20220316-21-8v92uv.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=501&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">The Daintree drought experiment we are running examines the effect of much less rainfall on the rainforest.</span>
<span class="attribution"><span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>Up on the crane, we’ve discovered that insects in the canopy may respond differently to drought stresses compared to those lower down in the forest. </p>
<p>We found more insects feeding on sap and fungi in drought-stressed trees down in the understorey, while we found little change in the canopy insects. This suggests insects up high are either very mobile or that the large canopy trees are less affected by drought. </p>
<h2>Australian research could benefit from more canopy cranes</h2>
<p>If we are to answer important questions about how ecosystems will function as the climate changes, we could benefit from more cranes. Six cranes have proved vital to Western Sydney University’s <a href="https://www.westernsydney.edu.au/hie/EucFACE">large scale experiment</a> on how Australian forests, animals and soils will fare at 550 parts per million of carbon dioxide (we’re currently at 400).</p>
<p>While nimble new technologies like drones give us exciting new data on canopies, canopy cranes will have a place for years to come. That’s because drones cannot give humans direct access to the canopy. </p>
<p>As the Daintree crane ages, questions will arise over whether it’s worth replacing when the time comes. The fact that understorey and canopy plants respond differently to drought shows us we cannot simply extrapolate what happens at ground level to what happens at height in the rainforest. </p>
<p>Canopy cranes give us vital access and make possible studies across whole forest ecosystems. Australia’s only tropical forest canopy crane has proven its worth.</p><img src="https://counter.theconversation.com/content/176253/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Nigel Stork receives funding from the Australian Research Council </span></em></p><p class="fine-print"><em><span>Claire Gely receives funding from the Australian Research Council. </span></em></p><p class="fine-print"><em><span>Susan Laurance works for James Cook University that runs the Daintree Rainforest Observatory. Susan Laurance has received ARC funding to support her drought experiment at the Daintree Rainforest Observatory.</span></em></p>The best way to experience a rainforest canopy is by crane - and researchers have made full use of Australia’s first canopy crane.Nigel Stork, Emeritus Professor in the Centre for Planetary Health and Food Security, Griffith UniversityClaire Gely, Postdoctoral research fellow, James Cook UniversitySusan Laurance, Professor, James Cook UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1734162022-02-02T13:08:50Z2022-02-02T13:08:50ZThe great Amazon land grab – how Brazil’s government is clearing the way for deforestation<figure><img src="https://images.theconversation.com/files/442638/original/file-20220125-23-sjc83.jpg?ixlib=rb-1.1.0&rect=7%2C14%2C1590%2C1123&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">A satellite captured large and small deforestation patches in Amazonas State in 2015. The forest loss has escalated since then.</span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/news-photo/natural-satellite-image-of-deforestation-on-the-banks-of-news-photo/627792180">USGS/NASA Landsat data/Orbital Horizon/Gallo Images/Getty Images</a></span></figcaption></figure><p>Imagine that a group of politicians decide that Yellowstone National Park is too big, so they downsize the park by a million acres, then sell that land in a private auction.</p>
<p>Outrageous? Yes. Unheard of? No. <a href="https://iopscience.iop.org/article/10.1088/1748-9326/ab1e24">It’s happening</a> with increasing frequency in the Brazilian Amazon. </p>
<p>The most widely publicized threat to the Amazonian rainforest is deforestation. A new study by European scientists released March 7, 2022, finds that tree clearing and less rainfall over the past 20 years have left <a href="https://www.nature.com/articles/s41558-022-01287-8">over 75% of the region increasingly less resilient to disturbances</a>, suggesting the rainforest may be nearing a tipping point for dieback. Fewer trees mean less moisture evaporating into the atmosphere to fall again as rain. </p>
<p>We have studied the Amazon’s changing hydroclimate, the role of deforestation and <a href="https://doi.org/10.1080/00139157.2021.1842711">evidence that the Amazon is being pushed toward a tipping point</a> – as well as what that means for different regions, biodiversity and climate change.</p>
<p>While the rise in deforestation is clear, less well understood are the sources driving it – particularly the way public lands are being converted to private holdings in a land grab <a href="https://www.researchgate.net/profile/Gabriel-Cardoso-Carrero">we’ve</a> <a href="https://scholar.google.com/citations?user=qcS5yogAAAAJ&hl=en">been</a> <a href="https://scholar.google.com/citations?user=PTEKYYoAAAAJ&hl=en">studying</a>
for the past decade. </p>
<p>Much of this land is cleared for cattle ranches and soybean farms, <a href="https://interactive.pri.org/2018/10/amazon-carbon/science.html">threatening biodiversity and the Earth’s climate</a>. Prior research has quantified how much public land has been grabbed, but only for one type of public land called “<a href="https://doi.org/10.1016/j.landusepol.2020.104863">undesignated public forests</a>.” Our research provides a complete account across all classes of public land. </p>
<p>We looked at Amazonia’s most active deforestation frontier, southern Amazonas State, starting in 2012 as rates of deforestation began to increase <a href="https://www.cell.com/one-earth/pdfExtended/S2590-3322(19)30081-8">because of loosened regulatory oversight</a>. Our research shows how land grabs are tied to accelerating deforestation spearheaded by wealthy interests, and how Brazil’s National Congress, by changing laws, is <a href="http://www.planalto.gov.br/ccivil_03/_ato2015-2018/2017/lei/l13465.htm">legitimizing these land grabs</a>. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/442639/original/file-20220125-17-6i1s1l.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A section of forest showing different stages of deforestation." src="https://images.theconversation.com/files/442639/original/file-20220125-17-6i1s1l.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/442639/original/file-20220125-17-6i1s1l.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=398&fit=crop&dpr=1 600w, https://images.theconversation.com/files/442639/original/file-20220125-17-6i1s1l.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=398&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/442639/original/file-20220125-17-6i1s1l.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=398&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/442639/original/file-20220125-17-6i1s1l.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=500&fit=crop&dpr=1 754w, https://images.theconversation.com/files/442639/original/file-20220125-17-6i1s1l.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=500&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/442639/original/file-20220125-17-6i1s1l.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=500&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Three stages of deforestation: cleared land where the forest has recently been burned to create pasture; pastureland; and forest being burned.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/news-photo/aerial-view-of-amazon-rainforest-deforestation-and-farm-news-photo/462437532">Ricardo Funari/Brazil Photos/LightRocket via Getty Images</a></span>
</figcaption>
</figure>
<h2>How the Amazon land grab began</h2>
<p>Brazil’s modern land grab started in the 1970s, when the military government began offering free land to encourage mining industries and farmers to move in, <a href="https://origins.osu.edu/article/amazon-rainforest-under-threat-Bolsonaro-fires-agrobusiness-indigenous-Brazil?language_content_entity=en">arguing that national security</a> depended on developing the region. It took lands that had been under state jurisdictions since colonial times and allocated them to rural settlement, granting 150- to 250-acre holdings to poor farmers. </p>
<p>Federal and state governments ultimately designated over 65% of Amazonia to several public interests, including rural settlement. For biodiversity, they created conservation units, some allowing traditional resource use and subsistence agriculture. Leftover government lands are generally referred to as <a href="http://www.bibliotecaflorestal.ufv.br/handle/123456789/4031">“vacant or undesignated public lands.”</a> </p>
<h2>Tracking the land grab</h2>
<p>Studies have estimated that by 2020, <a href="https://ipam.org.br/wp-content/uploads/2021/04/Amazo%CC%82nia-em-Chamas-7-Florestas-pu%CC%81blicas-na%CC%83o-destinadas.pdf">32% of “undesignated public forests”</a> had been grabbed for private use. But this is only part of the story, because land grabbing is now affecting many types of public land.</p>
<p>Importantly, land grabs now impact conservation areas and indigenous territories, where private holdings are forbidden. </p>
<figure class="align-center ">
<img alt="A herd of cattle on grass with thick forest behind them." src="https://images.theconversation.com/files/442640/original/file-20220125-15-wy06rh.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/442640/original/file-20220125-15-wy06rh.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=402&fit=crop&dpr=1 600w, https://images.theconversation.com/files/442640/original/file-20220125-15-wy06rh.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=402&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/442640/original/file-20220125-15-wy06rh.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=402&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/442640/original/file-20220125-15-wy06rh.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=505&fit=crop&dpr=1 754w, https://images.theconversation.com/files/442640/original/file-20220125-15-wy06rh.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=505&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/442640/original/file-20220125-15-wy06rh.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=505&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Cattle on land cleared in the Jamanxim National Forest in 2020.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/news-photo/land-grabbing-cattle-raising-and-deforestation-illegal-news-photo/1228648531">Marco Antonio Rezende/Brazil Photos/LightRocket via Getty Images</a></span>
</figcaption>
</figure>
<p>We compared the boundaries of self-declared private holdings in the government’s Rural Environmental Registry database, known as CAR, with the boundaries of all public lands in southern Amazonas State. The region has 50,309 square miles in conservation units. Of these, we found that <a href="https://www.datawrapper.de/_/JbEql/">10,425 square miles, 21%</a>, have been “grabbed,” or declared in the CAR register as private between 2014 and 2020. </p>
<p>In the United States, this would be like having 21% of the national parks disappear into private property.</p>
<p>Our measurement is probably an underestimate, given that <a href="https://doi.org/10.1016/j.landusepol.2014.06.026">not all grabbed lands are registered</a>. Some land grabbers now use CAR <a href="https://www.socioambiental.org/en/noticias-socioambientais/even-before-approval-a-land-grab-draft-law-is-already-destroying-the-amazon">to establish claims that could become legal</a> with changes in the law.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/440680/original/file-20220113-25-10q4hm4.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/440680/original/file-20220113-25-10q4hm4.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=383&fit=crop&dpr=1 600w, https://images.theconversation.com/files/440680/original/file-20220113-25-10q4hm4.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=383&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/440680/original/file-20220113-25-10q4hm4.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=383&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/440680/original/file-20220113-25-10q4hm4.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=482&fit=crop&dpr=1 754w, https://images.theconversation.com/files/440680/original/file-20220113-25-10q4hm4.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=482&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/440680/original/file-20220113-25-10q4hm4.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=482&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">A map of the region showing deforestation and public lands.</span>
<span class="attribution"><span class="source">Gabriel Cardoso Carrero</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<p>Land grabs put the rainforest at risk by <a href="https://doi.org/10.1088/1748-9326/ab1e24">increasing deforestation</a>. In southern Amazonas, <a href="https://images.theconversation.com/files/440680/original/file-20220113-25-10q4hm4.png">our research reveals that twice as much deforestation occurred on illegal as opposed to legal CAR holdings between 2008 and 2021</a>, a relative magnitude that is growing. </p>
<h2>Large deforestation patches point to wealth</h2>
<p>So who are these land grabbers? </p>
<p>In Pará State, Amazonas State’s neighbor, deforestation in the 1990s <a href="https://doi.org/10.1111/1467-8306.9302008">was dominated by poor family farms in rural settlements</a>. On average, these households accumulated 120 acres of farmland after several decades by opening 4-6 acres of forest every few years in clearings visible on satellite images as deforestation patches. </p>
<p>Since then, <a href="https://www.datawrapper.de/_/JbEql/">patch sizes have grown dramatically</a> in the region, with most deforestation occurring on illicit holdings whose patches are much larger than on legal holdings. </p>
<p><iframe id="JbEql" class="tc-infographic-datawrapper" src="https://datawrapper.dwcdn.net/JbEql/12/" height="400px" width="100%" style="border: none" frameborder="0"></iframe></p>
<p>Large deforestation patches <a href="https://doi.org/10.1007/s00267-020-01354-w">indicate the presence of wealthy grabbers</a>, given the cost of clearing land.</p>
<p>Land grabbers benefit by selling the on-site timber and by subdividing what they’ve grabbed for sale in small parcels. Arrest records and research by groups such as Transparency International Brasil show that <a href="https://comunidade.transparenciainternacional.org.br/grilagem-de-terras">many of them are involved in criminal enterprises</a> that use the land for money laundering, tax evasion and illegal mining and logging.</p>
<p>In the 10-year period before President Jair Bolsonaro took office, <a href="http://terrabrasilis.dpi.inpe.br/app/map/deforestation?hl=en">satellite data</a> showed two deforestation patches exceeding 3,707 acres in Southern Amazonas. Since his election in 2019, we can identify nine massive clearings with an average size of 5,105 acres. The clearance and preparation cost for each Bolsonaro-era deforestation patch, legal or illicit, would be about US$353,000. </p>
<h2>Legitimizing land grabbing</h2>
<p>Brazil’s National Congress has been making it easier to grab public land. </p>
<p><a href="http://www.planalto.gov.br/ccivil_03/_ato2015-2018/2017/lei/l13465.htm">A 2017 change in the law</a> expanded the legally allowed size of private holdings in undesignated public lands and in rural settlements. This has reclassified over 1,000 square miles of land that had been considered illegal in 2014 as legal in southern Amazonas. Of all illegal <a href="https://www.car.gov.br/#/baixar">CAR claims</a> in undesignated public lands and rural settlements in 2014, <a href="http://atlasagropecuario.imaflora.org/mapa">we found that 94% became legal in 2017</a>.</p>
<p>Congress is now considering two additional pieces of legislation. One <a href="https://legis.senado.leg.br/sdleg-getter/documento?dm=9050818&ts=1639516395952&disposition=inline">would legitimize land grabs up to 6,180 acres, about 9.5 square miles</a>, in all undesignated public forests – an amount <a href="http://www.planalto.gov.br/ccivil_03/_ato2015-2018/2017/lei/l13465.htm">already allowed by law</a> in other types of undesignated public lands. The second would legitimize large holdings on about <a href="https://www.camara.leg.br/proposicoesWeb/prop_mostrarintegra;jsessionid=node0ncik9mq5phv818u4p592bgsuc3415152.node0?codteor=2066398&filename=Tramitacao-PL+4348/2019">80,000 square miles of land once meant for the poor</a>. </p>
<p>Our research also shows that the federal government increased the amount of public land up for grabs in southern Amazonas by shrinking rural settlements by 16%, just over 2,000 square miles, between <a href="https://link.springer.com/content/pdf/10.1007/s00267-016-0783-2.pdf">2015</a> and <a href="https://certificacao.incra.gov.br/csv_shp/export_shp.py">2020</a>. <a href="https://governancadeterras.com.br/wp-content/uploads/2018/03/Andre%CC%81-Segura-Tomasi-PAF-Curuquete%CC%82-Grilagem-de-Terras-e-Viole%CC%82ncia-Agra%CC%81ria-SulAM-1.pdf">Large ranches are now absorbing that land</a>. Similar downsizing of public land has affected <a href="https://muse.jhu.edu/article/627431/pdf?casa_token=w5cmTxINMOYAAAAA:SwlFEGwJj4BsjBSYggfqbr57fsSgCyOw9AcykDICyjSIzl05hFLFhRADSEJENKFDyqyf4Z5_lQ">Amazonia’s national parks</a>. </p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/c4-KpR1HrNs?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Satellite images over time show how deforestation spread in the Amazon.</span></figcaption>
</figure>
<h2>What can turn this around?</h2>
<p>Because of <a href="https://doi.org/10.1126/science.1248525">policy interventions and the greening of agricultural supply chains</a>, deforestation in the Brazilian Amazon fell after 2005, reaching a low point in 2012, when it began trending up again <a href="https://doi.org/10.1016/j.landusepol.2020.105072">because of weakening environmental governance and reduced surveillance</a>.</p>
<p>Other countries <a href="https://www.reuters.com/article/us-climatechange-amazon-norway/norway-to-complete-1-billion-payment-to-brazil-for-protecting-amazon-idUSKCN0RF1P520150915">have helped Brazil with billions of dollars</a> to protect the Amazon for the good of the climate, but in the end, the land belongs to Brazil. Outsiders have limited power to influence its use.</p>
<p>At the U.N. climate summit in 2021, 141 countries – including Brazil – signed a <a href="https://ukcop26.org/glasgow-leaders-declaration-on-forests-and-land-use/">pledge to end deforestation by 2030</a>. This pledge holds potential because, unlike past ones, the private sector has committed <a href="https://cnr.ncsu.edu/news/2021/11/cop26-deforestation-pledge-a-promising-solution-with-an-uncertain-future/">$7.2 billion to reduce agriculture’s impact on the forest</a>. In our view, the global community can help by insisting that supply chains for Amazonian beef and soybean products originate on lands deforested long ago and whose legality is long-standing.</p>
<p><em>This article was updated March 7, 2022, with new research suggesting the Amazon is nearing a tipping point.</em></p>
<p>[<em>Over 140,000 readers rely on The Conversation’s newsletters to understand the world.</em> <a href="https://memberservices.theconversation.com/newsletters/?source=inline-140ksignup">Sign up today</a>.]</p><img src="https://counter.theconversation.com/content/173416/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Gabriel Cardoso Carrero received funding from the Tropical Conservation and Development Program at the University of Florida to conduct fieldwork related to this research. </span></em></p><p class="fine-print"><em><span>Cynthia S. Simmons and Robert T. Walker do not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and have disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Land grabs spearheaded by wealthy interests are accelerating deforestation, and Brazil’s National Congress is working to legitimize them.Gabriel Cardoso Carrero, Graduate Student Fellow and PhD Candidate in Geography, University of FloridaCynthia S. Simmons, Professor of Geography, University of FloridaRobert T. Walker, Professor of Latin American Studies and Geography, University of FloridaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1598492021-07-13T13:27:41Z2021-07-13T13:27:41ZThe COVID-19 pandemic is affecting conservation efforts in Madagascar<figure><img src="https://images.theconversation.com/files/404528/original/file-20210604-23-1ijdhi.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">The Coquerel Sifaka in its natural environment in a Malagasy national park. </span> <span class="attribution"><span class="source">Eugen Haag/Shutterstock</span></span></figcaption></figure><p>The effects of the <a href="https://theconversation.com/africa/covid-19">COVID-19 pandemic</a>, and the restriction policies used to mitigate the spread of the virus, are being felt all over the world. It affects all parts of life <a href="https://pubmed.ncbi.nlm.nih.gov/32292203/">including conservation</a> especially in developing countries like Madagascar. </p>
<p>Madagascar’s natural environment faces multiple challenges. These <a href="https://www.grida.no/resources/1336">include</a> deforestation, erosion, a changing climate, <a href="https://news.mongabay.com/2020/12/as-minister-and-activists-trade-barbs-madagascars-forests-burn/">agriculture fires</a>,
hunting and the over-collection of animals and plants from the wild. One of the biggest hurdles, which exacerbates these issues, is that poverty is widespread in Madagascar. It’s estimated that <a href="https://borgenproject.org/poverty-in-madagascar-5/">75%</a> of people in Madagascar live on less than $1.90 per day, and so many depend on natural resources. </p>
<p>There are about <a href="https://news.mongabay.com/2017/09/how-effective-is-conservation-in-madagascar-series-starts-next-week/">500 conservation projects</a> which are trying to address these challenges and provide employment to local communities. </p>
<p>I collaborated with a group of conservation managers and researchers, mostly from Madagascar, to assess exactly how the pandemic has affected conservation activities. <a href="https://onlinelibrary.wiley.com/doi/10.1111/btp.12967">Our paper</a> is based on our personal experiences and involvement in establishing management strategies during the pandemic.</p>
<p>We found that the pandemic challenged existing conservation structures and management. The issue is that most of Madagascar’s conservation and research projects are conceptualised and funded from abroad – the Global North. Non-governmental organisations on the ground implement their activities with the help of communities living close to protected areas. </p>
<p>Because of COVID-19 travel restrictions, several activities were forced to stop. This included vital training and biodiversity monitoring.</p>
<p>This situation provides us with the opportunity to re-examine strategies and research approaches to build resilience for future crises. The foundation of which lies with the true empowerment of local communities, conservationists and researchers.</p>
<h2>Challenges and coping strategies</h2>
<p>Our research involved members of organisations that manage multiple sites and protected areas across Madagascar. These included <a href="https://www.wwf.mg/">WWF Madagascar</a>, the <a href="https://www.aspinallfoundation.org/the-aspinall-foundation/working-around-the-world/madagascar/">Aspinall Foundation</a>, the <a href="https://www.missouribotanicalgarden.org/plant-science/plant-science/africa/madagascar.aspx">Missouri Botanical Garden</a> in Madagascar and the <a href="https://www.parcs-madagascar.com/">Madagascar National Parks</a>. The type of activities they carry out include both research and conservation.</p>
<p>Prior to the pandemic, activities were directed and funded by local and international agencies. Although there are initiatives that emerged locally, typically foreigners would lead and manage the projects. Malagasies (often those that live around the conservation areas) were usually employed to take on basic roles. For instance as project assistants, field guiding and patrolling. These activities provided them with an additional income to subsistence agriculture. </p>
<p>We found that restrictions, taken to reduce the spread of the new coronavirus, had a dramatic effect on conservation and research activities. Travel from abroad and within the country reduced the ability of projects to conduct activities. Foreigners, who were running projects, couldn’t come in. And there were also challenges managing activities from the capital, Antananarivo. </p>
<p>Border closures also meant international tourists and researchers couldn’t come into Madagascar. This resulted in less financial resources for conservation activities. For instance, park entrance and research permit fees are often used to fund conservation activities such as surveillance activities. They also provide park guides with an income. </p>
<p>In addition to a loss of income, in some cases project costs grew. This was because staff had to work from home, which increased communication expenses, and because local communities needed to report to head offices using phones. There were also additional costs related to health safety measures, such as masks and sanitisers.</p>
<p>Because there’s less surveillance activity, and also because many communities living close to protected areas had lost their supplementary income, there’s been an increase in illegal activities <a href="https://news.mongabay.com/2020/05/as-visitors-vanish-madagascars-protected-areas-suffer-a-devastating-blow/">inside some</a> national parks. This includes more hunting, logging and charcoal production.</p>
<p>In addition, environmental education and awareness activities for local communities living around protected areas ceased. </p>
<p>Not all local communities lost their work. In some places local communities were relied on to continue conservation and research activities, like reforestation and forest surveillance. But, because they weren’t adequately trained, this compromised the project.</p>
<p>Forest rangers, usually accompanied by permanent staff, had to perform habitat and species monitoring alone. But they faced challenges. This relates mostly to the transfer or proper storage of monitoring data because of the lack of technological knowledge and reduced connectivity in some remote sites. </p>
<h2>Improving the model</h2>
<p>All of these insights make a strong case for a change in Madagascar’s conservation model. In recent years, scientists and researchers <a href="https://news.mongabay.com/2017/09/local-approaches-to-conservation-may-be-the-most-effective-study-finds/">have argued</a> that locally-based conservation activities are more resilient as they engage and provide benefits to local communities. </p>
<p>Our <a href="https://onlinelibrary.wiley.com/doi/10.1111/btp.12967">paper</a> supports this. Projects should be more independent so that they can continue to run without such a heavy reliance on human resources from abroad. More needs to be done to ensure that the workforce is predominantly local, and driven by locals. </p>
<p>Projects should also provide leadership opportunities to local managers and researchers.</p>
<p>Communities living near protected areas have benefited from the efforts of NGOs and conservation organisations. However, such an approach should include possibilities for diversifying livelihoods that take into account local needs and values. </p>
<p>We hope that the lessons we have learned in Madagascar during COVID-19 will help to drive conservation and research in developing countries towards a more inclusive, sustainable, and equitable model. This would help to improve the success of conservation activities.</p><img src="https://counter.theconversation.com/content/159849/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Estelle Razanatsoa receives funding from the Southern African Science Service Centre (SASSCAL) and the African Origins Platform (AOP).</span></em></p>Most of Madagascar’s conservation and research projects are conceptualised and funded from abroad.Estelle Razanatsoa, Postdoctoral Fellow, Plant Conservation Unit (PCU), University of Cape TownLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1581812021-04-23T04:25:09Z2021-04-23T04:25:09ZThere aren’t enough trees in the world to offset society’s carbon emissions – and there never will be<figure><img src="https://images.theconversation.com/files/394270/original/file-20210409-15-v9z3jp.jpeg?ixlib=rb-1.1.0&rect=114%2C131%2C5349%2C2940&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">A tropical rainforest in South America.</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/tropical-rainforest-stunning-view-borneo-sunrise-1474114259">Shutterstock/BorneoRimbawan</a></span></figcaption></figure><p>One morning in 2009, I sat on a creaky bus winding its way up a mountainside in central Costa Rica, light-headed from diesel fumes as I clutched my many suitcases. They contained thousands of test tubes and sample vials, a toothbrush, a waterproof notebook and two changes of clothes.</p>
<p>I was on my way to <a href="https://tropicalstudies.org/portfolio/la-selva-research-station/">La Selva Biological Station</a>, where I was to spend several months studying the wet, lowland rainforest’s response to increasingly common droughts. On either side of the narrow highway, trees bled into the mist like watercolours into paper, giving the impression of an infinite primeval forest bathed in clouds.</p>
<hr>
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<p>As I gazed out of the window at the imposing scenery, I wondered how I could ever hope to understand a landscape so complex. I knew that thousands of researchers across the world were grappling with the same questions, trying to understand the fate of tropical forests in a rapidly changing world.</p>
<figure class="align-center ">
<img alt="Woman standing in the middle of a rainforest." src="https://images.theconversation.com/files/394498/original/file-20210412-19-4ssxpz.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/394498/original/file-20210412-19-4ssxpz.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/394498/original/file-20210412-19-4ssxpz.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/394498/original/file-20210412-19-4ssxpz.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/394498/original/file-20210412-19-4ssxpz.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/394498/original/file-20210412-19-4ssxpz.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/394498/original/file-20210412-19-4ssxpz.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Bonnie Waring conducting research at La Selva Biological Station, Costa Rica, 2011.</span>
<span class="attribution"><span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>Our society asks so much of these fragile ecosystems, which control freshwater availability for millions of people and are home to <a href="https://books.google.co.uk/books?hl=en&lr=&id=qACfAwAAQBAJ&oi=fnd&pg=PT132&ots=nNXh_eBGQ7&sig=fL7v4f_QIx2OeeFHNiae92MwlZU&redir_esc=y#v=onepage&q&f=false">two thirds</a> of the planet’s terrestrial biodiversity. And increasingly, we have placed a new demand on these forests – to save us from human-caused climate change. </p>
<p>Plants absorb CO₂ from the atmosphere, transforming it into leaves, wood and roots. This everyday miracle has spurred <a href="https://www.theguardian.com/environment/2019/jul/04/planting-billions-trees-best-tackle-climate-crisis-scientists-canopy-emissions">hopes</a> that plants – particularly fast growing tropical trees – can act as a natural brake on climate change, capturing much of the CO₂ emitted by fossil fuel burning. Across the world, governments, companies and conservation charities have pledged to conserve or plant <a href="https://trilliontrees.org/home">massive</a> numbers of trees.</p>
<hr>
<figure class="align-right ">
<img alt="" src="https://images.theconversation.com/files/288776/original/file-20190820-170910-8bv1s7.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/288776/original/file-20190820-170910-8bv1s7.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=600&fit=crop&dpr=1 600w, https://images.theconversation.com/files/288776/original/file-20190820-170910-8bv1s7.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=600&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/288776/original/file-20190820-170910-8bv1s7.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=600&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/288776/original/file-20190820-170910-8bv1s7.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=754&fit=crop&dpr=1 754w, https://images.theconversation.com/files/288776/original/file-20190820-170910-8bv1s7.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=754&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/288776/original/file-20190820-170910-8bv1s7.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=754&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption"></span>
</figcaption>
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<p><strong><em>This story is a collaboration between Conversation Insights and Apple News editors</em></strong>
<br><em>The Insights team generates <a href="https://theconversation.com/uk/topics/insights-series-71218">long-form journalism</a> and is working with academics from different backgrounds who have been engaged in projects to tackle societal and scientific challenges.</em> </p>
<hr>
<p>But the fact is that there aren’t enough trees to offset society’s carbon emissions – and there never will be. I recently conducted a <a href="https://www.frontiersin.org/articles/10.3389/ffgc.2020.00058/full">review</a> of the available scientific literature to assess how much carbon forests could feasibly absorb. If we absolutely maximised the amount of vegetation all land on Earth could hold, we’d sequester enough carbon to offset about ten years of greenhouse gas emissions at current rates. After that, there could be <a href="https://onlinelibrary.wiley.com/doi/abs/10.1046/j.1365-2486.2002.00536.x">no further</a> increase in carbon capture.</p>
<p>Yet the fate of our species is inextricably linked to the survival of forests and the <a href="https://www.unep-wcmc.org/news/earths-biodiversity-depends-on-the-worlds-forests">biodiversity</a> they contain. By rushing to plant millions of trees for carbon capture, could we be inadvertently damaging the very forest properties that make them so vital to our wellbeing? To answer this question, we need to consider not only how plants absorb CO₂, but also how they provide the sturdy green foundations for ecosystems on land. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/climate-scientists-concept-of-net-zero-is-a-dangerous-trap-157368">Climate scientists: concept of net zero is a dangerous trap</a>
</strong>
</em>
</p>
<hr>
<h2>How plants fight climate change</h2>
<p>Plants convert CO₂ gas into simple sugars in a process known as <a href="https://www.bbc.co.uk/bitesize/topics/zvrrd2p/articles/zn4sv9q">photosynthesis</a>. These sugars are then used to build the plants’ living bodies. If the captured carbon ends up in wood, it can be locked away from the atmosphere for many decades. As plants die, their tissues undergo decay and are incorporated into the soil. </p>
<figure class="align-center ">
<img alt="Microscopic close-up of leaf cells." src="https://images.theconversation.com/files/394545/original/file-20210412-23-1l2ji75.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/394545/original/file-20210412-23-1l2ji75.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=399&fit=crop&dpr=1 600w, https://images.theconversation.com/files/394545/original/file-20210412-23-1l2ji75.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=399&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/394545/original/file-20210412-23-1l2ji75.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=399&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/394545/original/file-20210412-23-1l2ji75.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=501&fit=crop&dpr=1 754w, https://images.theconversation.com/files/394545/original/file-20210412-23-1l2ji75.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=501&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/394545/original/file-20210412-23-1l2ji75.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=501&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Leaf under a microscope: the stoma which regulates oxygen and carbon dioxide can be seen.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/stoma-micrograph-leaf-under-microscope-organproducing-541977256">Shutterstock/Barbol</a></span>
</figcaption>
</figure>
<p>While this process naturally releases CO₂ through the respiration (or breathing) of microbes that break down dead organisms, some fraction of plant carbon can remain underground for decades or even <a href="https://www.nature.com/articles/s41586-019-1280-6">centuries</a>. Together, land plants and soils hold about <a href="https://archive.ipcc.ch/ipccreports/sres/land_use/index.php?idp=3">2,500 gigatonnes</a> of carbon – about three times more than is held in the atmosphere.</p>
<p>Because plants (especially trees) are such excellent natural storehouses for carbon, it makes sense that increasing the abundance of plants across the world could draw down atmospheric CO₂ concentrations. </p>
<p>Plants need four basic ingredients to grow: light, CO₂, water and nutrients (like nitrogen and phosphorus, the same elements present in plant fertiliser). Thousands of scientists across the world study how plant growth varies in relation to these four ingredients, in order to predict how vegetation will respond to climate change. </p>
<p>This is a surprisingly challenging task, given that humans are simultaneously modifying so many aspects of the natural environment by heating the globe, altering rainfall patterns, chopping large tracts of forest into tiny fragments and introducing alien species where they don’t belong. There are also over 350,000 species of flowering plants on land and each one responds to environmental challenges in unique ways. </p>
<p>Due to the complicated ways in which humans are <a href="https://theconversation.com/climate-change-weve-created-a-civilisation-hell-bent-on-destroying-itself-im-terrified-writes-earth-scientist-113055">altering</a> the planet, there is a lot of scientific <a href="https://science.sciencemag.org/content/366/6463/eaaz0388">debate</a> about the precise quantity of carbon that plants can absorb from the atmosphere. But researchers are in unanimous agreement that land ecosystems have a finite capacity to take up carbon.</p>
<figure class="align-center ">
<img alt="A graphic of a tree showing carbon storage." src="https://images.theconversation.com/files/394511/original/file-20210412-23-cu1h0u.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/394511/original/file-20210412-23-cu1h0u.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=550&fit=crop&dpr=1 600w, https://images.theconversation.com/files/394511/original/file-20210412-23-cu1h0u.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=550&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/394511/original/file-20210412-23-cu1h0u.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=550&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/394511/original/file-20210412-23-cu1h0u.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=691&fit=crop&dpr=1 754w, https://images.theconversation.com/files/394511/original/file-20210412-23-cu1h0u.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=691&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/394511/original/file-20210412-23-cu1h0u.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=691&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Where carbon is stored in a typical temperate forest in the UK.</span>
<span class="attribution"><a class="source" href="https://www.forestresearch.gov.uk/tools-and-resources/statistics/forestry-statistics/forestry-statistics-2018/uk-forests-andclimate-change/forest-carbon-stock/">UK Forest Research</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<p>If we ensure trees have enough water to drink, forests will grow tall and lush, creating shady canopies that starve smaller trees of light. If we increase the concentration of CO₂ in the air, plants will eagerly absorb it – until they can no longer extract enough fertiliser from the soil to meet their needs. Just like a baker making a cake, plants require CO₂, nitrogen and phosphorus in particular ratios, following a specific recipe for life. </p>
<p>In recognition of these fundamental constraints, scientists estimate that the earth’s land ecosystems can hold enough additional vegetation to absorb between <a href="https://www.frontiersin.org/articles/10.3389/ffgc.2020.00058/full">40 and 100</a> gigatonnes of carbon from the atmosphere. Once this additional growth is achieved (a process which will take a number of decades), there is no capacity for additional carbon storage on land. </p>
<p>But our society is currently pouring CO₂ into the atmosphere at <a href="https://www.globalcarbonproject.org/">a rate</a> of ten gigatonnes of carbon a year. Natural processes will struggle to keep pace with the deluge of greenhouse gases generated by the global economy. For example, I calculated that a single passenger on a round trip flight from Melbourne to New York City will emit roughly twice as much <a href="https://co2.myclimate.org/en/flight_calculators/new">carbon</a> (1600 kg C) as is contained in an <a href="https://www.researchgate.net/publication/281222046_Biomass_functions_applicable_to_oak_trees_grown_in_Central-European_forestry">oak</a> tree half a meter in diameter (750 kg C). </p>
<h2>Peril and promise</h2>
<p>Despite all these well recognised physical constraints on plant growth, there is a proliferating number of large scale efforts to increase vegetation cover to mitigate the climate emergency – a so called “nature-based” climate solution. The <a href="https://www.bonnchallenge.org/">vast</a> <a href="https://www.greatgreenwall.org/about-great-green-wall">majority</a> of these <a href="https://www.trilliontreecampaign.org/">efforts</a> focus on protecting or expanding forests, as trees contain many times more biomass than shrubs or grasses and therefore represent greater carbon capture potential.</p>
<p>Yet fundamental misunderstandings about carbon capture by land ecosystems can have devastating consequences, resulting in losses of biodiversity and an increase in CO₂ concentrations. This seems like a paradox – how can planting trees <a href="https://theconversation.com/planting-trees-must-be-done-with-care-it-can-create-more-problems-than-it-addresses-128259">negatively impact</a> the environment? </p>
<p>The answer lies in the subtle complexities of carbon capture in natural ecosystems. To avoid environmental damage, we must refrain from establishing forests where they naturally don’t belong, avoid “perverse incentives” to cut down existing forest in order to plant new trees, and consider how seedlings planted today might fare over the next several decades. </p>
<p>Before undertaking any expansion of forest habitat, we must ensure that trees are planted in the right place because not all ecosystems on land can or should support trees. Planting trees in ecosystems that are normally dominated by other types of vegetation <a href="https://science.sciencemag.org/content/366/6463/eaay7976">often fails</a> to result in long term carbon sequestration. </p>
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Read more:
<a href="https://theconversation.com/peat-bogs-restoring-them-could-slow-climate-change-and-revive-a-forgotten-world-139182">Peat bogs: restoring them could slow climate change – and revive a forgotten world</a>
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<p>One particularly illustrative example comes from Scottish <a href="https://www.wwf.org.uk/node/40261">peatlands</a> – vast swathes of land where the low-lying vegetation (mostly mosses and grasses) grows in constantly soggy, moist ground. Because decomposition is very slow in the acidic and waterlogged soils, dead plants accumulate over very long periods of time, creating <a href="https://peatlands.org/peat/peat/">peat</a>. It’s not just the vegetation that is preserved: peat bogs also mummify so-called “<a href="https://www.smithsonianmag.com/science-nature/europe-bog-bodies-reveal-secrets-180962770/">bog bodies</a>” – the nearly intact remains of men and women who died millennia ago. In fact, UK peatlands contain <a href="https://repository.uel.ac.uk/item/86047">20 times</a> more carbon than found in the nation’s forests.</p>
<p>But in the late 20th century, some Scottish bogs were drained for tree planting. Drying the soils allowed tree seedlings to establish, but also caused the decay of the peat to speed up. Ecologist <a href="http://geography.exeter.ac.uk/staff/index.php?web_id=Nina_Lindstrom_Friggens">Nina Friggens</a> and her colleagues at the University of Exeter <a href="https://onlinelibrary.wiley.com/doi/full/10.1111/gcb.15229">estimated</a> that the decomposition of drying peat released more carbon than the growing trees could absorb. Clearly, peatlands can best safeguard the climate when they are left to their own devices. </p>
<p>The same is true of grasslands and savannahs, where fires are a natural part of the landscape and often <a href="https://science.sciencemag.org/content/366/6463/eaay7976">burn trees</a> that are planted where they don’t belong. This principle also applies to <a href="https://science.sciencemag.org/content/366/6463/eaay8060">Arctic tundras</a>, where the native vegetation is covered by snow throughout the winter, reflecting light and heat back to space. Planting tall, dark-leaved trees in these areas can increase absorption of heat energy, and lead to local warming.</p>
<figure class="align-center ">
<img alt="Graphic showing how tree planting in different climate zones affects ecosystems." src="https://images.theconversation.com/files/394543/original/file-20210412-21-rtp9yg.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/394543/original/file-20210412-21-rtp9yg.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=379&fit=crop&dpr=1 600w, https://images.theconversation.com/files/394543/original/file-20210412-21-rtp9yg.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=379&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/394543/original/file-20210412-21-rtp9yg.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=379&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/394543/original/file-20210412-21-rtp9yg.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=476&fit=crop&dpr=1 754w, https://images.theconversation.com/files/394543/original/file-20210412-21-rtp9yg.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=476&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/394543/original/file-20210412-21-rtp9yg.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=476&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Implications of large-scale tree planting in various climatic zones and ecosystems.</span>
<span class="attribution"><a class="source" href="https://www.imperial.ac.uk/grantham/publications/briefing-papers/what-role-can-forests-play-in-tackling-climate-change.php">Stacey McCormack/Köppen climate classification</a>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>But even planting trees in forest habitats can lead to negative environmental outcomes. From the perspective of both carbon sequestration and biodiversity, all forests are not equal – naturally established forests contain more species of plants and animals than plantation forests. They often hold more carbon, too. But policies aimed at promoting tree planting can unintentionally incentivise deforestation of well established natural habitats. </p>
<p>A recent high-profile example concerns the Mexican government’s <a href="https://www.bloomberg.com/news/features/2021-03-08/a-tree-planting-program-in-mexico-may-encourage-deforestation">Sembrando Vida</a> programme, which provides direct payments to landowners for planting trees. The problem? Many rural landowners cut down well established older forest to plant seedlings. This decision, while quite sensible from an economic point of view, has resulted in the loss of tens of thousands of hectares of mature forest. </p>
<p>This example demonstrates the risks of a narrow focus on trees as carbon absorption machines. Many well meaning organisations seek to plant the trees <a href="https://onelifeonetree.com/">which grow the fastest</a>, as this theoretically means a higher rate of CO₂ “drawdown” from the atmosphere. </p>
<p>Yet from a climate perspective, what matters is not how quickly a tree can grow, but how much carbon it contains at maturity, and how long that carbon resides in the ecosystem. As a forest ages, it reaches what ecologists call a “steady state” – this is when the amount of carbon absorbed by the trees each year is perfectly balanced by the CO₂ released through the <a href="https://www.anu.edu.au/news/all-news/plants-release-more-carbon-dioxide-into-atmosphere-than-expected">breathing of the plants</a> themselves and the trillions of decomposer microbes underground.</p>
<p>This phenomenon has led to an erroneous perception that old forests are not useful for climate mitigation because they are no longer growing rapidly and sequestering additional CO₂. The misguided “solution” to the issue is to prioritise tree planting ahead of the conservation of already established forests. This is analogous to draining a bathtub so that the tap can be turned on full blast: the flow of water from the tap is greater than it was before – but the total capacity of the bath hasn’t changed. Mature forests are like bathtubs full of carbon. They are making an important contribution to the large, but finite, quantity of carbon that can be locked away on land, and there is little to be gained by disturbing them.</p>
<p>What about situations where fast growing forests are cut down every few decades and replanted, with the extracted wood used for other climate-fighting purposes? While harvested wood can be a very good carbon store if it ends up in long lived products (like houses or other buildings), surprisingly little timber is <a href="https://link.springer.com/article/10.1007/s11027-016-9722-z">used in this way</a>.</p>
<p>Similarly, burning wood as a source of biofuel may have a positive climate impact if this reduces total consumption of fossil fuels. But forests managed as biofuel plantations provide little in the way of protection for <a href="https://conbio.onlinelibrary.wiley.com/doi/full/10.1111/j.1523-1739.2008.01096.x">biodiversity</a> and some research <a href="https://theconversation.com/biofuels-turn-out-to-be-a-climate-mistake-heres-why-64463">questions</a> the benefits of biofuels for the climate in the first place.</p>
<h2>Fertilise a whole forest</h2>
<p>Scientific estimates of carbon capture in land ecosystems depend on how those systems respond to the mounting challenges they will face in the coming decades. All forests on Earth – even the most pristine – are vulnerable to warming, changes in rainfall, increasingly severe wildfires and pollutants that drift through the Earth’s atmospheric currents. </p>
<p>Some of these pollutants, however, contain lots of nitrogen (plant fertiliser) which could potentially give the global forest a growth boost. By producing massive quantities of agricultural chemicals and burning fossil fuels, humans have massively <a href="https://link.springer.com/article/10.1007/s13280-020-01464-z">increased</a> the amount of “reactive” nitrogen available for plant use. Some of this nitrogen is dissolved in rainwater and reaches the forest floor, where it can <a href="https://www.nature.com/articles/ngeo721">stimulate</a> tree growth in some areas. </p>
<p>As a young researcher fresh out of graduate school, I wondered whether a type of under-studied ecosystem, known as <a href="https://iopscience.iop.org/article/10.1088/1748-9326/aa5968">seasonally dry</a> tropical forest, might be particularly responsive to this effect. There was only one way to find out: I would need to fertilise a whole forest. </p>
<p>Working with my postdoctoral adviser, the ecologist <a href="https://cbs.umn.edu/contacts/jennifer-s-powers">Jennifer Powers</a>, and expert botanist Daniel Pérez Avilez, I outlined an area of the forest about as big as two football fields and divided it into 16 plots, which were randomly assigned to different fertiliser treatments. For the next three years (2015-2017) the plots became among the most intensively studied forest fragments on Earth. We measured the growth of each individual tree trunk with specialised, hand-built instruments called dendrometers.</p>
<figure class="align-center ">
<img alt="Trees with a metal measurement device wrapped around them." src="https://images.theconversation.com/files/394500/original/file-20210412-15-3tp4mv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/394500/original/file-20210412-15-3tp4mv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=337&fit=crop&dpr=1 600w, https://images.theconversation.com/files/394500/original/file-20210412-15-3tp4mv.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=337&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/394500/original/file-20210412-15-3tp4mv.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=337&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/394500/original/file-20210412-15-3tp4mv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=424&fit=crop&dpr=1 754w, https://images.theconversation.com/files/394500/original/file-20210412-15-3tp4mv.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=424&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/394500/original/file-20210412-15-3tp4mv.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=424&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Dendrometer devices wrapped around tree trunks to measure growth.</span>
<span class="attribution"><span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>We used baskets to catch the dead leaves that fell from the trees and installed mesh bags in the ground to track the growth of roots, which were painstakingly washed free of soil and weighed. The most challenging aspect of the experiment was the application of the fertilisers themselves, which took place three times a year. Wearing raincoats and goggles to protect our skin against the caustic chemicals, we hauled back-mounted sprayers into the dense forest, ensuring the chemicals were evenly applied to the forest floor while we sweated under our rubber coats.</p>
<p>Unfortunately, our gear didn’t provide any protection against angry wasps, whose nests were often concealed in overhanging branches. But, our efforts were worth it. After three years, we could calculate all the leaves, wood and roots produced in each plot and assess carbon captured over the study period. We <a href="https://esajournals.onlinelibrary.wiley.com/doi/abs/10.1002/ecy.2691">found</a> that most trees in the forest didn’t benefit from the fertilisers – instead, growth was strongly tied to the amount of rainfall in a given year. </p>
<figure class="align-right ">
<img alt="A blue basket with dead leaves in it." src="https://images.theconversation.com/files/394502/original/file-20210412-21-h3mzk.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/394502/original/file-20210412-21-h3mzk.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=337&fit=crop&dpr=1 600w, https://images.theconversation.com/files/394502/original/file-20210412-21-h3mzk.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=337&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/394502/original/file-20210412-21-h3mzk.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=337&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/394502/original/file-20210412-21-h3mzk.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=424&fit=crop&dpr=1 754w, https://images.theconversation.com/files/394502/original/file-20210412-21-h3mzk.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=424&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/394502/original/file-20210412-21-h3mzk.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=424&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">One of the baskets for catching dead leaves.</span>
<span class="attribution"><span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>This suggests that nitrogen pollution won’t boost tree growth in these forests as long as droughts continue to <a href="https://link.springer.com/article/10.1007/s10584-016-1790-2">intensify</a>. To make the same prediction for other forest types (wetter or drier, younger or older, warmer or cooler) such studies will need to be repeated, adding to the library of knowledge developed through similar experiments over the decades. Yet researchers are in a race against time. Experiments like this are slow, painstaking, sometimes backbreaking work and humans are changing the face of the planet faster than the scientific community can respond.</p>
<h2>Humans need healthy forests</h2>
<p>Supporting natural ecosystems is an important tool in the arsenal of strategies we will need to combat climate change. But land ecosystems will never be able to absorb the quantity of carbon released by fossil fuel burning. Rather than be lulled into false complacency by <a href="https://www.bloomberg.com/news/features/2021-04-05/a-top-u-s-seller-of-carbon-offsets-starts-investigating-its-own-projects">tree planting schemes</a>, we need to cut off emissions at their source and search for additional strategies to remove the carbon that has already accumulated in the atmosphere.</p>
<p>Does this mean that current campaigns to protect and expand forest are a poor idea? Emphatically not. The protection and expansion of natural habitat, particularly forests, is absolutely vital to ensure the health of our planet. Forests in temperate and tropical zones contain <a href="https://www.iucn.org/resources/issues-briefs/forests-and-climate-change">eight</a> out of every ten species on land, yet they are under increasing threat. Nearly <a href="https://ourworldindata.org/land-use">half</a> of our planet’s habitable land is devoted to agriculture, and forest clearing for cropland or pasture is continuing apace. </p>
<p>Meanwhile, the atmospheric mayhem caused by climate change is intensifying wildfires, worsening droughts and systematically heating the planet, posing an escalating threat to forests and the wildlife they support. What does that mean for our species? Again and again, researchers have demonstrated <a href="https://www.nature.com/articles/nature11148?report=reader">strong links</a> between biodiversity and so-called “ecosystem services” – the multitude of benefits the natural world provides to humanity.</p>
<p>Carbon capture is just one ecosystem service in an incalculably long list. Biodiverse ecosystems provide a dizzying array of pharmaceutically active compounds that <a href="https://pubs.acs.org/doi/10.1021/acs.jnatprod.5b01055">inspire</a> the creation of new drugs. They provide food security in ways both direct (think of the millions of people whose main source of protein is wild fish) and indirect (for example, a large fraction of crops are <a href="https://www.pnas.org/content/113/1/146">pollinated</a> by wild animals). </p>
<p>Natural ecosystems and the millions of species that inhabit them still inspire technological developments that revolutionise human society. For example, take the polymerase chain reaction (“<a href="https://en.wikipedia.org/wiki/Polymerase_chain_reaction">PCR</a>”) that allows crime labs to catch criminals and your local pharmacy to provide a COVID test. PCR is only possible because of a special protein synthesised by a humble bacteria that lives in hot springs. </p>
<p>As an ecologist, I worry that a simplistic perspective on the role of forests in climate mitigation will inadvertently lead to their decline. Many tree planting efforts focus on the number of saplings planted or their initial rate of growth – both of which are poor indicators of the forest’s ultimate carbon storage capacity and even poorer metric of biodiversity. More importantly, viewing natural ecosystems as “climate solutions” gives the misleading impression that forests can function like an infinitely absorbent mop to clean up the ever increasing flood of human caused CO₂ emissions. </p>
<p>Luckily, many big organisations dedicated to forest expansion are incorporating ecosystem health and biodiversity into their metrics of success. A little over a year ago, I visited an enormous reforestation experiment on the Yucatán Peninsula in Mexico, operated by <a href="https://www1.plant-for-the-planet.org/">Plant-for-the-Planet</a> – one of the world’s largest tree planting organisations. After realising the challenges inherent in large scale ecosystem restoration, Plant-for-the-Planet has initiated a series of experiments to understand how different interventions early in a forest’s development might improve tree survival. </p>
<p>But that is not all. Led by Director of Science <a href="https://lwerden.mystrikingly.com/">Leland Werden</a>, researchers at the site will study how these same practices can jump-start the recovery of native biodiversity by providing the ideal environment for seeds to germinate and grow as the forest develops. These experiments will also help land managers decide when and where planting trees benefits the ecosystem and where forest regeneration can occur naturally. </p>
<p>Viewing forests as reservoirs for biodiversity, rather than simply storehouses of carbon, complicates decision making and may require shifts in policy. I am all too aware of these challenges. I have spent my entire adult life studying and thinking about the carbon cycle and I too sometimes can’t see the forest for the trees. One morning several years ago, I was sitting on the rainforest floor in Costa Rica measuring CO₂ emissions from the soil – a relatively time intensive and solitary process. </p>
<p>As I waited for the measurement to finish, I spotted a strawberry poison dart frog – a tiny, jewel-bright animal the size of my thumb – hopping up the trunk of a nearby tree. Intrigued, I watched her progress towards a small pool of water held in the leaves of a spiky plant, in which a few tadpoles idly swam. Once the frog reached this miniature aquarium, the tiny tadpoles (her children, as it turned out) vibrated excitedly, while their mother deposited unfertilised eggs for them to eat. As I later learned, frogs of this species (<a href="https://esajournals.onlinelibrary.wiley.com/doi/full/10.1890/13-0927.1">Oophaga pumilio</a>) take very diligent care of their offspring and the mother’s long journey would be repeated every day until the tadpoles developed into frogs.</p>
<p>It occurred to me, as I packed up my equipment to return to the lab, that thousands of such small dramas were playing out around me in parallel. Forests are so much more than just carbon stores. They are the unknowably complex green webs that bind together the fates of millions of known species, with millions more still waiting to be discovered. To survive and thrive in a future of dramatic global change, we will have to respect that tangled web and our place in it. </p>
<hr>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/313478/original/file-20200204-41481-1n8vco4.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/313478/original/file-20200204-41481-1n8vco4.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=112&fit=crop&dpr=1 600w, https://images.theconversation.com/files/313478/original/file-20200204-41481-1n8vco4.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=112&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/313478/original/file-20200204-41481-1n8vco4.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=112&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/313478/original/file-20200204-41481-1n8vco4.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=140&fit=crop&dpr=1 754w, https://images.theconversation.com/files/313478/original/file-20200204-41481-1n8vco4.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=140&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/313478/original/file-20200204-41481-1n8vco4.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=140&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption"></span>
</figcaption>
</figure>
<p><em>For you: more from our <a href="https://theconversation.com/uk/topics/insights-series-71218?utm_source=TCUK&utm_medium=linkback&utm_campaign=TCUKengagement&utm_content=InsightsUK">Insights series</a>:</em></p>
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<li><p><em><a href="https://theconversation.com/climate-scientists-concept-of-net-zero-is-a-dangerous-trap-157368?utm_source=TCUK&utm_medium=linkback&utm_campaign=TCUKengagement&utm_content=InsightsUK">Climate scientists: concept of net zero is a dangerous trap</a></em></p></li>
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<p class="fine-print"><em><span>Bonnie Waring is a scientific consultant to Plant-for-the-Planet and The Carbon Community, a charity aimed at enhancing carbon capture and protecting biodiversity in reforestation projects. She has received research funding to study ecosystem carbon dynamics in reforestation trials operated by both organizations.</span></em></p>Even if they can’t save us from climate change, society still depends on forests.Bonnie Waring, Senior Lecturer, Grantham Institute - Climate Change and Environment, Imperial College LondonLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1567772021-03-23T15:20:51Z2021-03-23T15:20:51ZRegrowing a tropical forest – is it better to plant trees or leave it to nature?<figure><img src="https://images.theconversation.com/files/390123/original/file-20210317-17-1i4c0te.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C7360%2C4263&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">Thammanoon Khamchalee / shutterstock</span></span></figcaption></figure><p>The destruction of tropical forest is a major contributor to biodiversity loss and the <a href="https://theconversation.com/we-tracked-300-000-trees-only-to-find-that-rainforests-are-losing-their-power-to-help-humanity-133122">climate crisis</a>. In response, conservationists and scientists like us are debating how to best catalyse recovery of these forests. How do you take a patch of earth littered with tree stumps, or even a grassy pasture or palm oil plantation, and turn it back into a thriving forest filled with its original species?</p>
<p>Foresters have traditionally relied on planting trees, which seems obvious enough. Yet this approach has attracted criticism from some <a href="https://www.nature.com/articles/d41586-019-01026-8">restoration ecologists</a>, who argue that planting and caring for young trees is expensive and an inefficient use of scarce resources. They also point out that the carbon locked up in growing trees is quickly released into the atmosphere if plantations are harvested and used for short-lived wood products such as paper or cardboard.</p>
<p>There are even some well-documented case studies where tree planting has had negative outcomes. For instance, when forest cover was expanded on the Loess Plateau in China, soil erosion increased and there was <a href="https://www.sciencedirect.com/science/article/pii/S1040618215002700">less water available for people and agriculture</a>. In Chile, subsidies for tree planting created a perverse incentive to plant trees instead of conserving natural forests. In the period between 2006 and 2011, the policy triggered a <a href="https://www.nature.com/articles/s41893-020-0547-0">loss of natural forest cover</a> and no net change in the amount of carbon stored in trees across the country.</p>
<h2>Leave it to nature?</h2>
<p>The alternative approach is referred to as <a href="https://www.nature.com/articles/s41586-020-2686-x?proof=t">natural regeneration</a>. This generally means protecting the area you want to regrow, perhaps with fences or new legislation, and then letting the forest recover spontaneously through dormant seeds lying buried in soil or with seeds dispersed by wind or animals.</p>
<p>Natural regeneration has many advantages: it requires limited infrastructure or technical know-how and is often cheap to implement. There is also widespread evidence that natural regeneration has been effective at catalysing the recovery of <a href="https://conbio.onlinelibrary.wiley.com/doi/full/10.1111/conl.12709">forest biomass</a> and <a href="https://advances.sciencemag.org/content/2/5/e1501639">biodiversity</a>. It is tempting to view natural regeneration as a win-win solution for economic development and the environment.</p>
<p>But socio-ecological realities complicate this positive message. The critical first step is to secure the gains from any interventions, as both naturally regenerating and actively restored forest may continue to be degraded through over-harvesting if they are not protected. This requires the close participation of local communities and landowners in decision making, to ensure that the benefits and costs of forest restoration are distributed appropriately.</p>
<p>Natural regeneration often relies on animals to disperse the seeds. But in many tropical forests these animals, especially the larger birds and mammals that disperse the largest seeds, have been severely depleted by hunting. In the <a href="https://advances.sciencemag.org/content/1/11/e1501105.full">Atlantic forests of Brazil</a>, trees with larger seeds have more dense wood, and loss of large seed-dispersing mammals and birds such as tapirs and toucans may result in recovering forests becoming dominated by light-wooded trees which store less carbon. In south-east Asian rainforests, the dominant trees have winged seeds that <a href="https://onlinelibrary.wiley.com/doi/full/10.1002/ece3.1469">spin in the air over short distances</a>, and therefore can’t recolonise sites more than a few tens of metres away from a seed source</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/390140/original/file-20210317-21-uify67.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A colourful bird sits on branch" src="https://images.theconversation.com/files/390140/original/file-20210317-21-uify67.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/390140/original/file-20210317-21-uify67.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=397&fit=crop&dpr=1 600w, https://images.theconversation.com/files/390140/original/file-20210317-21-uify67.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=397&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/390140/original/file-20210317-21-uify67.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=397&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/390140/original/file-20210317-21-uify67.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=499&fit=crop&dpr=1 754w, https://images.theconversation.com/files/390140/original/file-20210317-21-uify67.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=499&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/390140/original/file-20210317-21-uify67.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=499&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Toucans use their big beaks to disperse seeds around Brazil’s Atlantic forest.</span>
<span class="attribution"><span class="source">Rafael Martos Martins / shutterstock</span></span>
</figcaption>
</figure>
<p>Tropical forests often regenerate naturally on abandoned lands distant from the original, untouched forests. Yet if limitations on seed dispersal mean they lack the tree species that were originally dominant, then these young forests will store carbon less quickly and become home to fewer animal species.</p>
<h2>A 20-year study</h2>
<p>So how does natural regeneration match up against a more active approach? We recently published the results of <a href="https://science.sciencemag.org/content/369/6505/838.abstract">a 20-year study</a> that tried to address this question. After a tropical forest in Malaysia had been logged back in the 1980s and 1990s, our international team first measured how much carbon it still stored in its remaining trees. We then tracked carbon storage across two decades in areas that had been left to regenerate naturally, and adjacent patches that had been actively restored by tree planting and cutting back competitive weeds and climbers.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/390706/original/file-20210320-17-tgbska.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/390706/original/file-20210320-17-tgbska.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/390706/original/file-20210320-17-tgbska.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/390706/original/file-20210320-17-tgbska.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/390706/original/file-20210320-17-tgbska.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/390706/original/file-20210320-17-tgbska.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/390706/original/file-20210320-17-tgbska.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/390706/original/file-20210320-17-tgbska.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Research assistant Ridly Mansau records tree trunk diameters.</span>
<span class="attribution"><span class="source">Sonny Royal / SEARRP</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>When we compared the two, we found that the actively restored forest was storing carbon 50% faster than the forest left to regenerate naturally. This finding was supported by measuring the size and number of trees on the ground and by <a href="https://www.sciencedirect.com/science/article/pii/S0006320717310790">laser scanning the forest from an aeroplane</a>. </p>
<p>We don’t yet know how that increase was achieved. One possibility is that the planted trees filled the large gaps between the few large trees left by loggers, whereas equivalent patches in naturally regenerating forest were out of reach of natural seed dispersal. Greater spacing of young trees, combined with weeding out the competing vines and careful species selection, may have allowed them to grow faster and accumulate more carbon through time.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/389650/original/file-20210315-21-gvbgk5.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="plants grow in beds under a shady canopy" src="https://images.theconversation.com/files/389650/original/file-20210315-21-gvbgk5.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/389650/original/file-20210315-21-gvbgk5.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/389650/original/file-20210315-21-gvbgk5.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/389650/original/file-20210315-21-gvbgk5.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/389650/original/file-20210315-21-gvbgk5.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/389650/original/file-20210315-21-gvbgk5.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/389650/original/file-20210315-21-gvbgk5.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Rainforest tree seedlings are grown in a nursery before being planted in the restored forest.</span>
<span class="attribution"><span class="source">Sonny Royal / SEARRP</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>The restoration treatment was expensive, costing about US$1,500 (£1,080) per hectare of treated forest over the lifetime of the project. Some of this cost could be recovered through selling carbon credits (where polluters would pay for forest restoration to “offset” their own emissions), but covering the whole cost is unrealistic at current prices.</p>
<p>The high cost will inevitably limit the use of active restoration to the most disconnected or degraded sites where it is least likely that forests would regenerate naturally. Though we’ll have to rely on animals and wind to spread seeds in many settings, in other settings planting trees will be an ecological necessity we can’t afford to reject.</p><img src="https://counter.theconversation.com/content/156777/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>David Burslem received funding from the UK Natural Environment Research Council that contributed to this research. </span></em></p><p class="fine-print"><em><span>Christopher Philipson now works for the tropical forest protection developer Permian Global <a href="https://permianglobal.com">https://permianglobal.com</a>
</span></em></p><p class="fine-print"><em><span>Mark Cutler received funding from the UK Natural Environment Research Council and the Carnegie Trust for the Universities of Scotland. The authors worked with the South East Asian Rainforest Research Programme on the project in Malaysia.</span></em></p>Scientists in Malaysia monitored a forest for 20 years after deforestation.David Burslem, Professor of Forest Ecology and Diversity, University of AberdeenChristopher Philipson, Senior Researcher, Department of Environmental Systems Science, ETH Zürich, Swiss Federal Institute of Technology ZurichMark Cutler, Professor of Physical Geography, University of DundeeLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1425992020-07-29T13:36:32Z2020-07-29T13:36:32ZChimpanzees once helped African rainforests recover from a major collapse<p>Most people probably think that the rainforest of central and west Africa, the second largest in the world, has been around for millions of years. However recent research suggests that it is mostly <a href="https://authors.elsevier.com/a/1bJrP_KzR0AIh4">just 2,000 or so years old</a>. The forest reached roughly its modern state following five centuries of regeneration after it was massively fragmented when the dry season suddenly became longer some 2,500 years ago. </p>
<p>This process was not linked to humans. The forest recovery was instead made possible by seed dispersers including chimpanzees, which helped spread the slower-growing rainforest tree species. However, dispersers such as chimpanzees are now threatened by deforestation and hunting, often for bushmeat. When combined with climate change, the resilience of the rainforests seems less guaranteed for the future. </p>
<p>I began thinking about natural processes in African forests back in 1993, when I was with my wife-to-be trying to follow wild chimpanzees next to <a href="https://www.janegoodall.org.uk/our-programmes/gombe-stream-research-centre">Jane Goodall’s famous group</a> at Gombe, in Tanzania. We were inspired by one of the directors of research at Gombe, <a href="http://pin.primate.wisc.edu/idp/idp/entry/377">Anthony Collins</a>, who suggested that the chimpanzees might be influencing the composition of the forest for their own nutritional needs, by what fruits they pooed out and where. A kind of “proto gardening”.</p>
<p>And then unexpectedly I had to leave the chimpanzees after I succeeded in getting a small grant to study past vegetation change using fossilised pollen, but in the Andes.</p>
<p>A few years later, I found myself giving lectures at Cambridge on human impacts over the past 10,000 years, and suddenly “returning” not only to the tropical rainforests of Africa, but their history. At the time, scientists thought humans were largely responsible for the collapse of the forests from 3,000 years ago. </p>
<p>The first few scientific papers I read used the abundance of pollen from the oil palm tree, preserved in the dated layers of lake muds, as an indicator of human activity. The oil palm is the same species often planted on a <a href="https://www.nationalgeographic.com/environment/2018/12/palm-oil-destroying-rainforests-household-items/">massive industrial scale</a> in the tropics today, and since it’s always been an important source of nutrition for people in the region, scientists had assumed it indicated the presence of humans. </p>
<p>Shortly after, I began working in a <a href="http://www.isem.univ-montp2.fr/fr/">pollen laboratory</a> in Montpellier in southern France which had a long-term focus on African forest history. There, my simplified view of fossilised oil palm pollen equalling the presence of humans was totally overturned. </p>
<p>Rainforest history records were being amassed that indicated the near-decimation of rainforests <a href="https://opendocs.ids.ac.uk/opendocs/bitstream/handle/20.500.12413/8672/IDSB_33_1_10.1111-j.1759-5436.2002.tb00003.x.pdf?sequence=1">some 2,500 years ago</a> in the Congo Basin and across a huge expanse stretching from modern-day Senegal to Rwanda. As there was only very limited archaeological evidence of thinly dispersed human populations, humans could not have been responsible for the almost synchronous destruction on such a huge scale.</p>
<p><strong>Africa hosts the world’s second largest rainforest</strong></p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/348401/original/file-20200720-102864-s7j20.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="map of showing the different ecosystems across Africa" src="https://images.theconversation.com/files/348401/original/file-20200720-102864-s7j20.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/348401/original/file-20200720-102864-s7j20.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=540&fit=crop&dpr=1 600w, https://images.theconversation.com/files/348401/original/file-20200720-102864-s7j20.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=540&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/348401/original/file-20200720-102864-s7j20.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=540&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/348401/original/file-20200720-102864-s7j20.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=678&fit=crop&dpr=1 754w, https://images.theconversation.com/files/348401/original/file-20200720-102864-s7j20.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=678&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/348401/original/file-20200720-102864-s7j20.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=678&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Tropical rainforests (dark green) still cover much of central and west Africa.</span>
<span class="attribution"><span class="source">Vzb83 / wiki</span>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span>
</figcaption>
</figure>
<p>So what did cause these rainforests to collapse? It turns out the answer was not humans, but climate change.</p>
<p>In a paper recently published in the journal <a href="https://authors.elsevier.com/a/1bJrP_KzR0AIh4">Global Planetary Change</a>, my colleagues <a href="https://www.researchgate.net/profile/Pierre_Giresse">Pierre Giresse</a>, <a href="https://univ-montpellier.academia.edu/JeanMALEY">Jean Maley</a> and I use the many vegetation records available across central and west Africa to show that approximately 2,500 years ago, the length of the dry season increased. Rainforests became highly fragmented, and savanna vegetation – grasses, scattered shrubs and trees – moved in. </p>
<p>In the centuries that followed, the forests regenerated spontaneously, including with species such as the oil palm. The oil palm demands a lot of light and so thrives in open areas or in the gaps created in forests when the canopy opens up rather than in the dense centre. Thus it often acts as a “pioneer species” allowing the forest to regrow. </p>
<p>But the oil palm’s large seeds are too heavy to be blown in the wind. They therefore need to be dispersed in the poo of animals such as chimpanzees which are able to swallow the large seeds and for whom the bright orange flesh can be an <a href="https://bioone.org/journals/AMBIO-A-Journal-of-the-Human-Environment/volume-35/issue-3/0044-7447(2006)35%255b124:TIOLTR%255d2.0.CO%3B2/The-Importance-of-Local-Tree-Resources-around-Gombe-National-Park/10.1579/0044-7447(2006)35%255b124:TIOLTR%255d2.0.CO%3B2.short">important part of the diet</a>. And this is how chimps and other seed-dispersers played a crucial role in regenerating Africa’s rainforests.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/348402/original/file-20200720-18366-bwh3c9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="bright orange oil palm fruit" src="https://images.theconversation.com/files/348402/original/file-20200720-18366-bwh3c9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/348402/original/file-20200720-18366-bwh3c9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/348402/original/file-20200720-18366-bwh3c9.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/348402/original/file-20200720-18366-bwh3c9.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/348402/original/file-20200720-18366-bwh3c9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/348402/original/file-20200720-18366-bwh3c9.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/348402/original/file-20200720-18366-bwh3c9.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Oil palm fruit swallowed and deposited in faeces by chimpanzee at Gombe National Park.</span>
<span class="attribution"><span class="source">D Mwacha A Collins / Jane Goodall Institute</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<h2>Seed dispersers under threat</h2>
<p>When we began this research, we could not see how relevant it would become during the current pandemic. Now climate change, deforestation and hunting are all heavily impacting those same forests. The bushmeat market is contributing to removing <a href="https://theconversation.com/canary-species-can-sing-songs-that-warn-of-ecosystem-collapse-64138">keystone species</a> such as chimpanzees. Without animals to move seeds around – especially the largest and heaviest seeds – the natural composition and regeneration of forests is threatened. </p>
<p>At the turn of the 20th century there were around 1 million chimpanzees, but today only an estimated <a href="https://www.janegoodall.org.uk/chimpanzees/chimpanzee-central/15-chimpanzees/chimpanzee-central/22-state-of-the-wild-chimpanzee">172,000-300,000 remain in the wild</a>. Chimps and other seed-dispersing species provide a valuable service and must be better protected in order to protect the forests themselves, and prevent further unforeseen impacts.</p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/348403/original/file-20200720-31-8pg4f1.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Cusano the chimpanzee clings to a branch" src="https://images.theconversation.com/files/348403/original/file-20200720-31-8pg4f1.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/348403/original/file-20200720-31-8pg4f1.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=910&fit=crop&dpr=1 600w, https://images.theconversation.com/files/348403/original/file-20200720-31-8pg4f1.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=910&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/348403/original/file-20200720-31-8pg4f1.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=910&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/348403/original/file-20200720-31-8pg4f1.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1144&fit=crop&dpr=1 754w, https://images.theconversation.com/files/348403/original/file-20200720-31-8pg4f1.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1144&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/348403/original/file-20200720-31-8pg4f1.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1144&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Cusano, an alpha male in Gombe, Tanzania, was among those who died in the 1996 respiratory outbreak.</span>
<span class="attribution"><span class="source">Alex Chepstow-Lusty</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>For example, the transmission of diseases to humans has also been <a href="https://www.bbc.com/news/science-environment-52529830">linked to the bushmeat trade</a>. And transmission is not necessarily one way. In June 1996, three years after my wife and I left the chimps at Mitumba in Gombe National Park, possibly up to half the group died within a few days of a <a href="https://www.academia.edu/15330525/The_importance_of_local_tree_resources_around_Gombe_National_Park_Western_Tanzania_Implications_for_humans_and_chimpanzees._Ambio._35_3_130-135">respiratory disease outbreak</a> that was likely transmitted to them by humans.</p>
<p>Perhaps there is a lot more resilience in these tropical forest ecosystems than we can predict. But without chimpanzees and other animals as dispersers, the emptier forests that may eventually grow back would be a sad replacement. Maybe we need to consider the true value of chimp poo, and those that produce it.</p><img src="https://counter.theconversation.com/content/142599/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Alex Chepstow-Lusty does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>But with chimps now endangered, we risk losing their forest-rebuilding abilities.Alex Chepstow-Lusty, Associate Researcher, Quaternary Palaeoenvironments Group, University of CambridgeLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1390712020-05-22T14:39:03Z2020-05-22T14:39:03ZWe found 2˚C of warming will push most tropical rainforests above their safe ‘heat threshold’<figure><img src="https://images.theconversation.com/files/337026/original/file-20200522-124836-sy8z3w.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">Komjomo / shutterstock</span></span></figcaption></figure><p>As they photosynthesise and grow, tropical forests remove enormous amounts of carbon from the atmosphere, reducing global warming. However, forests are also themselves affected by this warming. If it gets too hot or too dry, trees will grow less and may start to die faster, decomposing and releasing that carbon back into the atmosphere. </p>
<p>This is why scientists like us are concerned that climate change will mean death outweighs growth, and tropical forests will eventually switch to releasing more carbon into the atmosphere than they take out. Our new research, published in the journal <a href="https://science.sciencemag.org/content/368/6493/869.full">Science</a>, shows that tropical forests can resist small increases in temperature – but only up to a point.</p>
<p>Such forests are found right across the tropics and although they’re generally hot and wet, this simplification hides a lot of variation in climate. Some forests at the southern edge of the Amazon reach 35˚C in the hottest months of the year, while others towards the foothills of the Andes reach no more than 26˚C. The jungles of the western Amazon and Borneo are wet all year round, while elsewhere in Amazonia and in Africa there are “rainforests” that have virtually no rainfall in the driest months. We used this variation to understand how climate affects the amount of carbon tropical forests store, and to predict how this might change in the future.</p>
<p>Why did we look at variation between locations to predict changes over time? Because, since individual trees live for a long time, even decades of monitoring cannot tell us exactly how a forest will respond to climate change in the long term. For example, <a href="https://onlinelibrary.wiley.com/doi/full/10.1111/gcb.14413">Amazonian forests</a> that are drying fastest are slowly shifting towards more drought-adapted tree species, but this is only evident if we look at the youngest trees. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/337079/original/file-20200522-124840-1xrgvd5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/337079/original/file-20200522-124840-1xrgvd5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/337079/original/file-20200522-124840-1xrgvd5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=338&fit=crop&dpr=1 600w, https://images.theconversation.com/files/337079/original/file-20200522-124840-1xrgvd5.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=338&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/337079/original/file-20200522-124840-1xrgvd5.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=338&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/337079/original/file-20200522-124840-1xrgvd5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=424&fit=crop&dpr=1 754w, https://images.theconversation.com/files/337079/original/file-20200522-124840-1xrgvd5.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=424&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/337079/original/file-20200522-124840-1xrgvd5.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=424&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Measuring trees in Ndoubale-Ndoki National Park, Congo.</span>
<span class="attribution"><span class="source">Aida Cuni Sanchez</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>Looking at variations between different tropical forests gives us a unique perspective on how tropical forests might respond to future climatic conditions, as we can observe how forests grow in a particular climate after having had time to adapt. For example, we can use the difference in the amount of carbon stored by forests growing at 30˚C and 32˚C as a guide for how the former might respond over the long-term to a 2˚C increase in temperature. </p>
<p>So, we joined efforts with 223 other researchers. The international team measured more than half a million trees in 813 forests across the tropics. In each forest patch we recorded tree diameter, species and height. And a few years later we went back to measure how much each tree had grown, if some had died, or if new ones had established. Each tree had a numerical tag, which allowed us to track them over their lives. Overall we identified about 10,000 tree species and made two million measurements of diameter, across 24 tropical countries. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/337047/original/file-20200522-124818-1lxlvsw.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/337047/original/file-20200522-124818-1lxlvsw.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/337047/original/file-20200522-124818-1lxlvsw.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=619&fit=crop&dpr=1 600w, https://images.theconversation.com/files/337047/original/file-20200522-124818-1lxlvsw.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=619&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/337047/original/file-20200522-124818-1lxlvsw.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=619&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/337047/original/file-20200522-124818-1lxlvsw.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=778&fit=crop&dpr=1 754w, https://images.theconversation.com/files/337047/original/file-20200522-124818-1lxlvsw.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=778&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/337047/original/file-20200522-124818-1lxlvsw.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=778&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Above 32˚C, carbon stocks diminish – fast.</span>
<span class="attribution"><a class="source" href="https://science.sciencemag.org/content/368/6493/869/tab-pdf">Sullivan et al / Science</a></span>
</figcaption>
</figure>
<p>We found that tropical forests can tolerate small changes in temperatures, but only up to a point. Once annual mean daytime temperatures in the warmest part of the year hit 32˚C or more, these forests release four times as much carbon to the atmosphere per degree increase in temperature as they would below the threshold. This is mostly because hotter temperatures reduce tree growth, but it’s also down to heat combined with drought meaning trees are more likely to die and decompose, which releases carbon back into the atmosphere.</p>
<h2>Adaptation is possible – if we act now</h2>
<p>Our results indicate that we have an opportunity to ensure forests can adapt to climate change, but we need to act now. Firstly, we need to protect and connect the forests that remain, so that tree species are able to move as the climate warms. </p>
<p>But trees go from place to place very slowly: they can only “move” when animals or the wind carry their seeds somewhere else where climatic conditions are suitable. The more fragmented the forests, the less likely seeds can reach certain patches. Also, smaller patches are more affected by “edge effects” such as increased light, drier air and fire risks, creating challenging conditions for seeds to germinate and grow. Therefore, keeping forests connected is of crucial importance.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/337081/original/file-20200522-124822-14a827k.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/337081/original/file-20200522-124822-14a827k.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/337081/original/file-20200522-124822-14a827k.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/337081/original/file-20200522-124822-14a827k.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/337081/original/file-20200522-124822-14a827k.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/337081/original/file-20200522-124822-14a827k.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/337081/original/file-20200522-124822-14a827k.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/337081/original/file-20200522-124822-14a827k.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">The researchers behind the new study made more than 2 million tree measurements.</span>
<span class="attribution"><span class="source">Aida Cuni Sanchez</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>Secondly, we need to limit emissions. Even limiting global temperatures to 2°C above pre-industrial levels – already a best case scenario – will push nearly three-quarters of tropical forests above the 32°C heat threshold we identify. As each degree increase above the heat threshold releases 100 billion tonnes of CO₂ from tropical forests to the atmosphere, representing over 280 years of annual fossil fuel emissions by a country such as the UK, there is a clear incentive to avoid further warming.</p>
<p>Of course, reducing emissions is challenging. However, right now, humanity has a unique opportunity. During the current pandemic, emissions from transport, among other sectors, have been <a href="https://www.nature.com/articles/s41558-020-0797-x">significantly reduced</a>. So this shows that we humans can do it. We can design a healthier cooler future for all of us: rainforests and humans.</p><img src="https://counter.theconversation.com/content/139071/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Martin Sullivan was funded by grants from the European Research Council, Natural Environment Resarch Council and the Royal Society. This work is a collaboration with the RAINFOR (<a href="http://www.rainfor.org">www.rainfor.org</a>, South America), AfriTRON (<a href="http://www.afritron.org">www.afritron.org</a>, Africa) and T-Forces (<a href="http://www.tforces.net">www.tforces.net</a>) networks of researchers and the ForestPlots (<a href="http://www.forestplots.net">www.forestplots.net</a>) database.</span></em></p><p class="fine-print"><em><span>Aida Cuní Sanchez does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Massive study looked at more than half a million trees in 813 forests across the tropics.Aida Cuní Sanchez, Postdoctoral Research Associate, University of YorkMartin Sullivan, Lecturer in Statistical Ecology, Manchester Metropolitan UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1304442020-03-09T12:22:47Z2020-03-09T12:22:47ZDung beetles help rainforests regrow – but extreme drought and wildfires in the Amazon are killing them off<figure><img src="https://images.theconversation.com/files/316508/original/file-20200220-92526-w5ecx2.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C2385%2C1588&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">An Amazon forest in Brazil's Para state after deforestation and wildfires March 9, 2019. Unlike in some tropical forests, the animals of the Amazon are not adapted to survive fire.</span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/news-photo/members-of-the-ibama-forest-fire-brigade-fight-burning-in-news-photo/1167455725?adppopup=true">Gustavo Basso/NurPhoto via Getty Images</a></span></figcaption></figure><p>The dung beetle may <a href="https://theconversation.com/five-things-dung-beetles-do-with-a-piece-of-poo-47367">eat and nest in poop</a>, but its role in nature is anything but humble. </p>
<p>These hardshelled scarabs live on every continent except Antarctica, <a href="https://www.youtube.com/watch?v=uSTNyHkde08">recycling feces</a> and <a href="https://doi.org/10.1111/1365-2664.12821">suppressing parasites</a> that could otherwise harm people and animals. Dung beetles also <a href="https://doi.org/10.1098/rspb.2016.1634">spread both seeds and nutrients</a> into the soil, helping to maintain a healthy ecosystem.</p>
<p>Conversely, dung beetles suffer when an ecological system is struggling. In tropical forests, for example, stress caused by environmental disturbances causes dung beetles to <a href="https://doi.org/10.1002/ece3.2488">gain body fat</a> and <a href="https://doi.org/10.1016/j.foreco.2017.12.027">work less</a>. <a href="https://doi.org/10.1111/1365-2664.12657">Species diversity</a> declines.</p>
<p>That’s why, as <a href="https://scholar.google.com/citations?user=5srODa8AAAAJ&hl=da">Amazon</a> <a href="https://scholar.google.com/citations?hl=da&user=HYNoVoUAAAAJ&view_op=list_works&sortby=pubdate">researchers</a>, we use the marvelous, hard-working dung beetle to measure the ecological health of the world’s largest rainforest. Since 2010, we have collected and studied over 14,000 dung beetles from 98 different species in the vast and still wild interior of Brazil’s Santarém region, a remote corner of the Amazon forest – part of a long-term project with the <a href="https://www.rasnetwork.org/">Sustainable Amazon Network</a>.</p>
<p>Most recently, we studied dung beetles to assess the Amazon’s recovery from the intense drought and forest fires of 2015 and 2016, extreme climatic events brought on by <a href="https://theconversation.com/el-nino-is-over-but-has-left-its-mark-across-the-world-59823">the most severe El Niño on record</a>.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/316506/original/file-20200220-92512-1vqs5at.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/316506/original/file-20200220-92512-1vqs5at.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=338&fit=crop&dpr=1 600w, https://images.theconversation.com/files/316506/original/file-20200220-92512-1vqs5at.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=338&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/316506/original/file-20200220-92512-1vqs5at.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=338&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/316506/original/file-20200220-92512-1vqs5at.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=424&fit=crop&dpr=1 754w, https://images.theconversation.com/files/316506/original/file-20200220-92512-1vqs5at.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=424&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/316506/original/file-20200220-92512-1vqs5at.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=424&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">The hard-working Amazonian dung beetle.</span>
<span class="attribution"><span class="source">Filipe França</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<h2>Stressed beetles take less crap</h2>
<p>Some forests in our 10,586-square-mile research area were burned in the El Niño fires, which scorched <a href="https://doi.org/10.1098/rstb.2017.0312">4,000 square miles of the Amazon</a>. These climate-triggered fires are not to be confused with last year’s <a href="https://doi.org/10.1111/gcb.14872">Amazon fire crisis</a>, which was deforestation-related. Other Amazonian forests in our study experienced extreme drought but not fire. </p>
<p>We knew going into this project that Amazonian fauna are particularly sensitive to fire – unlike animals in Australia, which <a href="https://theconversation.com/animal-response-to-a-bushfire-is-astounding-these-are-the-tricks-they-use-to-survive-129327">have a long history of fire adaptation</a>. But our <a href="https://doi.org/10.1111/btp.12756">study</a>, which was published in the scientific journal <a href="https://onlinelibrary.wiley.com/journal/17447429">Biotropica</a> in February 2020, reveals that both forest fires and drought are far more damaging than previously thought. </p>
<p>Dung beetles are captured in traps baited with – what else? – human and pig poop. There we count and physically examine them. To assess their activity level, we trick dung beetles into dispersing seeds by building a small arena filled with a mix of dung and artificial seeds on the forest floor. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/316507/original/file-20200220-92502-11md6ap.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/316507/original/file-20200220-92502-11md6ap.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/316507/original/file-20200220-92502-11md6ap.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/316507/original/file-20200220-92502-11md6ap.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/316507/original/file-20200220-92502-11md6ap.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/316507/original/file-20200220-92502-11md6ap.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/316507/original/file-20200220-92502-11md6ap.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/316507/original/file-20200220-92502-11md6ap.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Researchers measuring beetles’ dung-removal and seed-dispersal services.</span>
<span class="attribution"><span class="source">Marizilda Cuppre/ RAS Network</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>Comparing our catches before and after the El Niño forest fires, we learned that almost 70% of dung beetles had disappeared. We believe that’s because most dung beetles <a href="https://doi.org/10.1890/14-1211.1">nest in shallow soil depths</a> of between zero to 6 inches, so <a href="https://doi.org/10.2307/2256168">fire heat</a> is likely to kill them. </p>
<p>The El Niño droughts likewise decimated the Amazonian dung beetle populations. Their populations dropped by about 60% in forests affected only by drought, not fire. </p>
<p>Together, extreme drought and forest fires in the Amazon had severely diminished the beetles’ ability to remove dung and spread seeds, which declined by 67% and 22%, respectively, in comparison to data recorded in 2010 – before El Niño. This reduced haul is probably the result of population loss. </p>
<p>Both the reduction in the number of dung beetles captured and their diminished waste disposal functions persisted even two years after El Niño. While dung beetle populations recover quickly in <a href="https://doi.org/10.1111/een.12705">fire-dependent ecosystems</a>, insect recovery from fire disturbance <a href="https://doi.org/10.1111/j.1466-882X.2004.00074.x">in tropical forests can take many years</a>. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/316504/original/file-20200220-92533-hm3meo.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/316504/original/file-20200220-92533-hm3meo.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/316504/original/file-20200220-92533-hm3meo.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/316504/original/file-20200220-92533-hm3meo.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/316504/original/file-20200220-92533-hm3meo.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/316504/original/file-20200220-92533-hm3meo.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/316504/original/file-20200220-92533-hm3meo.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/316504/original/file-20200220-92533-hm3meo.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Author Filipe França with an Amazonian dung beetle.</span>
<span class="attribution"><span class="source">Marizilda Cuppre/RAS Network</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<h2>Tropical beetles</h2>
<p>If both drought and fire kill off dung beetles, the Amazon forests are in serious trouble. </p>
<p>In damaged forests, <a href="https://besjournals.onlinelibrary.wiley.com/doi/full/10.1111/1365-2745.13358">most regrowth depends on seed dispersal</a> by animals. Dung beetles disperse the seeds that promote revegetation and spread nutrients in the soil, <a href="https://doi.org/10.1098/rspb.2016.1634">helping seedlings survive</a>.</p>
<p>They aren’t the only animals that play this critical ecological function. <a href="https://doi.org/10.1111/btp.12627">Tapirs</a>, <a href="https://doi.org/10.1111/j.1744-7429.1999.tb00125.x">monkeys</a>, <a href="https://doi.org/10.1080/12538078.1999.10515813">ants, bee beetles and even wasps</a> also spread the seeds that aid vegetation regrowth. </p>
<p>But many <a href="https://doi.org/10.1038/s41558-018-0225-7">studies</a> show that dung beetle responses to environmental stress are similar to those suffered by other seed-spreading animals necessary to tropical forest health. And climate change is likewise causing the <a href="https://theconversation.com/climate-change-is-killing-off-earths-little-creatures-109719">collapse of these insect populations</a>, killing off <a href="https://doi.org/10.1073/pnas.1722477115">ants, bees, butterflies and wasps</a>.</p>
<p>Without these important tropical animals, forests damaged by fire and drought will recover much more slowly. That means they may barely begin their regrowth before the next disaster. And with climate change projected to bring the tropics more intense and frequent droughts, along with <a href="http://dx.doi.org/10.1098/rstb.2019.0116">hotter and dry global temperatures</a>, such disasters will likely come ever more quickly.</p>
<p>From our field sites deep in the Amazon, we are rooting for all the little creeping and crawling creatures that <a href="https://www.jstor.org/stable/2386020?seq=1">keep the world running</a> – with, admittedly, some particular affection and concern for the humble dung beetle. </p>
<p>[<em>Like what you’ve read? Want more?</em> <a href="https://theconversation.com/us/newsletters?utm_source=TCUS&utm_medium=inline-link&utm_campaign=newsletter-text&utm_content=likethis">Sign up for The Conversation’s daily newsletter</a>.]</p><img src="https://counter.theconversation.com/content/130444/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Filipe França is also affiliated with Lancaster University and the Empresa Brasileira de Pesquisa Agropecuária, in Brazil. He receives funding from BNP Paribas Foundation and the Brazilian National Council for Scientific and Technological Development. His fieldwork was funded by the Natural Environment Research Council. </span></em></p><p class="fine-print"><em><span>Joice Ferreira receives funding from the Brazilian Research Council CNPq. She works for the Brazilian government research organization Empresa Brasileira de Pesquisa Agropecuária, or Embrapa.</span></em></p>A new study finds 70% of Amazonian dung beetles were killed by the severe fire and droughts of 2015 to 2016. By spreading seeds and poop, dung beetles fertilize forests and aid regrowth of vegetation.Filipe França, Researcher, Tropical Ecology, Universidade Federal do Pará (UFPA)Joice Ferreira, Researcher in Ecology, Universidade Federal do Pará (UFPA)Licensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1331222020-03-06T14:49:15Z2020-03-06T14:49:15ZWe tracked 300,000 trees only to find that rainforests are losing their power to help humanity<figure><img src="https://images.theconversation.com/files/318944/original/file-20200305-106610-15bfobk.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">Chokniti Khongchum / shutterstock</span></span></figcaption></figure><p>Tropical forests matter to each and every one of us. They suck colossal quantities of carbon out of the atmosphere, providing a crucial brake on the rate of climate change. Yet, new research we have just published <a href="https://doi.org/10.1038/s41586-020-2035-0">in Nature</a> shows that intact tropical forests are removing far less carbon dioxide than they used to.</p>
<p>The change is staggering. Across the 1990s intact tropical forests – those unaffected by logging or fires – removed roughly 46 billion tonnes of carbon dioxide from the atmosphere. This diminished to an estimated 25 billion tonnes in the 2010s. The lost sink capacity is 21 billion tonnes of carbon dioxide, equivalent to a decade of fossil fuel emissions from the UK, Germany, France and Canada combined.</p>
<p>How did we reach such an alarming conclusion, and how is it that nobody knew this before? The answer is that we – along with 181 other scientists from 36 countries – have spent years tracking individual trees deep in the world’s rainforests. </p>
<p>The idea is simple enough: we go and identify the tree species and measure the diameter and height of every individual tree in an area of forest. Then a few years later we return to exactly the same forest and re-measure all the trees again. We can see which grew, which died and if any new trees have grown.</p>
<p>These measurements allow us to calculate how much carbon is stored in a forest, and how it changes over time. By repeating the measurements enough times and in enough places, we can reveal long-term trends in carbon uptake.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/319089/original/file-20200306-118881-114hfxw.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/319089/original/file-20200306-118881-114hfxw.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/319089/original/file-20200306-118881-114hfxw.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=286&fit=crop&dpr=1 600w, https://images.theconversation.com/files/319089/original/file-20200306-118881-114hfxw.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=286&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/319089/original/file-20200306-118881-114hfxw.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=286&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/319089/original/file-20200306-118881-114hfxw.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=360&fit=crop&dpr=1 754w, https://images.theconversation.com/files/319089/original/file-20200306-118881-114hfxw.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=360&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/319089/original/file-20200306-118881-114hfxw.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=360&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Most of the world’s primary tropical rainforests are found in the Amazon, Central Africa or Southeast Asia.</span>
<span class="attribution"><a class="source" href="https://glad.umd.edu/gladmaps/globalmap.php#primary_humidtropical">Hansen/UMD/Google/USGS/NASA</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span>
</figcaption>
</figure>
<p>This is easier said than done. Tracking trees in tropical forests is challenging, particularly in equatorial Africa, home to the second largest expanse of tropical forest in the world. As we want to monitor forests that are not logged or affected by fire, we need to travel down the last road, to the last village, and last path, before we even start our measurements.</p>
<p>First we need partnerships with local experts who know the trees and often have older measurements that we can build upon. Then we need permits from governments, plus agreements with local villagers to enter their forests, and their help as guides. Measuring trees, even in the most remote location, is a team task.</p>
<p>The work can be arduous. We have spent a week in a dugout canoe to reach the plots in Salonga National Park in central Democratic Republic of the Congo, carried everything for a month-long expedition through swamps to reach plots in Nouabalé Ndoki National Park in the Republic of Congo, and ventured into Liberia’s last forests once the civil war ended. We’ve dodged elephants, gorillas and large snakes, caught scary tropical diseases like Congo red fever and narrowly missed an Ebola outbreak.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/319075/original/file-20200306-118913-1pj0vx2.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/319075/original/file-20200306-118913-1pj0vx2.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/319075/original/file-20200306-118913-1pj0vx2.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=376&fit=crop&dpr=1 600w, https://images.theconversation.com/files/319075/original/file-20200306-118913-1pj0vx2.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=376&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/319075/original/file-20200306-118913-1pj0vx2.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=376&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/319075/original/file-20200306-118913-1pj0vx2.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=473&fit=crop&dpr=1 754w, https://images.theconversation.com/files/319075/original/file-20200306-118913-1pj0vx2.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=473&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/319075/original/file-20200306-118913-1pj0vx2.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=473&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Wading through swamps in Nouabalé Ndoki National Park.</span>
<span class="attribution"><span class="source">Aida Cuní Sanchez</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>Days start early to make the most of a day in the field. Up at first light, out of your tent, get the coffee on the open fire. Then after a walk to the plot, we use aluminium nails that don’t hurt the trees to label them with unique numbers, paint to mark exactly where we measure a tree so we can find it next time, and a portable ladder to get above the buttresses of the big trees. Plus a tape measure to get the tree diameters and a laser to zap tree heights.</p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/318952/original/file-20200305-106573-jsxv41.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/318952/original/file-20200305-106573-jsxv41.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/318952/original/file-20200305-106573-jsxv41.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=800&fit=crop&dpr=1 600w, https://images.theconversation.com/files/318952/original/file-20200305-106573-jsxv41.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=800&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/318952/original/file-20200305-106573-jsxv41.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=800&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/318952/original/file-20200305-106573-jsxv41.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1005&fit=crop&dpr=1 754w, https://images.theconversation.com/files/318952/original/file-20200305-106573-jsxv41.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1005&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/318952/original/file-20200305-106573-jsxv41.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1005&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Researchers in Cameroon measure a 36 metre high tree.</span>
<span class="attribution"><span class="source">Wannes Hubau</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>After sometimes a week of travel, it takes four to five days for a team of five people to measure all 400 to 600 trees above 10 cm diameter in the average hectare of forest (100 metres x 100 metres). For our study, this was done for 565 different patches of forest grouped in two large research networks of forest observations, the <a href="http://www.afritron.org">African Tropical Rainforest Observatory Network </a> and the <a href="http://www.rainfor.org">Amazon Rainforest Inventory Network</a>.</p>
<p>This work means months away. For many years, each of us has spent several months a year in the field writing down diameter measurements on special waterproof water. In total we tracked more than 300,000 trees and made more than 1 million diameter measurements in 17 countries.</p>
<p>Managing the data is a major task. It all goes into a website we designed at the University of Leeds, <a href="https://www.forestplots.net/">ForestPlots.net</a>, which allows standardisation, whether the measurements come from Cameroon or Colombia.</p>
<p>Many months of detailed analysis and checking of the data followed, as did time for a careful write-up our findings. We needed to focus on the detail of individual trees and plots, while not losing sight of the big picture. It’s a hard balancing act.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/319077/original/file-20200306-118890-17akqvf.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/319077/original/file-20200306-118890-17akqvf.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/319077/original/file-20200306-118890-17akqvf.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/319077/original/file-20200306-118890-17akqvf.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/319077/original/file-20200306-118890-17akqvf.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/319077/original/file-20200306-118890-17akqvf.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/319077/original/file-20200306-118890-17akqvf.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/319077/original/file-20200306-118890-17akqvf.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">One of the authors in Rep. Congo with Noe Madingou of Marien Ngouabi University and other local guides and researchers.</span>
<span class="attribution"><span class="source">Aida Cuní Sanchez</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>The final part of our analysis looked to the future. We used a statistical model and estimates of future environmental change to estimate that by 2030 the African forests’ capacity to remove carbon will decrease by 14%, while Amazonian forests may stop removing carbon dioxide altogether by 2035. Scientists have long feared that one of Earth’s large carbon sinks would switch to become a source. This process has, unfortunately, begun.</p>
<p>The declining carbon sink results provide pretty grim news and not what we would like to report. But as scientists, we have a job is to follow the data wherever it takes us. That can be far into the rainforests of Congo, or onto the TV to tell people about our work. It’s the least we can do in the climate emergency we are currently living though. We will all need to play a role in solving this crisis.</p>
<hr>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/263883/original/file-20190314-28475-1mzxjur.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/263883/original/file-20190314-28475-1mzxjur.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=140&fit=crop&dpr=1 600w, https://images.theconversation.com/files/263883/original/file-20190314-28475-1mzxjur.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=140&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/263883/original/file-20190314-28475-1mzxjur.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=140&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/263883/original/file-20190314-28475-1mzxjur.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=176&fit=crop&dpr=1 754w, https://images.theconversation.com/files/263883/original/file-20190314-28475-1mzxjur.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=176&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/263883/original/file-20190314-28475-1mzxjur.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=176&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption"></span>
</figcaption>
</figure>
<p><em><a href="https://theconversation.com/imagine-newsletter-researchers-think-of-a-world-with-climate-action-113443?utm_source=TCUK&utm_medium=linkback&utm_campaign=TCUKengagement&utm_content=Imagineheader1133122">Click here to subscribe to our climate action newsletter. Climate change is inevitable. Our response to it isn’t.</a></em></p><img src="https://counter.theconversation.com/content/133122/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Simon Lewis has received funding from Natural Environment Research Council, the Royal Society, the European Union, the Leverhulme Trust, the Centre for International Forestry, National Parks Agency of Gabon, Microsoft Research, the Gordon and Betty Moore Foundation, the Greenpeace Fund, and the David and Lucile Packard Foundation.</span></em></p><p class="fine-print"><em><span>Aida Cuní Sanchez and Wannes Hubau do not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and have disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Scientists behind a major new study explain how they discovered these forests are becoming less able to sequester carbon.Wannes Hubau, Research Scientist, Royal Museum for Central AfricaAida Cuní Sanchez, Postdoctoral Research Associate, University of YorkSimon Lewis, Professor of Global Change Science at University of Leeds and, UCLLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1278782019-12-23T16:01:44Z2019-12-23T16:01:44ZLemurs are the world’s most endangered mammals, but planting trees can help save them<figure><img src="https://images.theconversation.com/files/306005/original/file-20191210-95173-4i8v47.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C4200%2C2785&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Black-and-white ruffed lemurs are important indicators of rainforest health.</span> <span class="attribution"><span class="source">Franck Rabenahy</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span></figcaption></figure><figure class="align-left ">
<img alt="" src="https://images.theconversation.com/files/304794/original/file-20191202-67017-h7zxl9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/304794/original/file-20191202-67017-h7zxl9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=470&fit=crop&dpr=1 600w, https://images.theconversation.com/files/304794/original/file-20191202-67017-h7zxl9.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=470&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/304794/original/file-20191202-67017-h7zxl9.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=470&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/304794/original/file-20191202-67017-h7zxl9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=591&fit=crop&dpr=1 754w, https://images.theconversation.com/files/304794/original/file-20191202-67017-h7zxl9.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=591&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/304794/original/file-20191202-67017-h7zxl9.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=591&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Madagascar, the world’s fourth-largest island, is a global biodiversity hotspot.</span>
<span class="attribution"><span class="source">Andrea Baden</span></span>
</figcaption>
</figure>
<p>The island of Madagascar off the southeastern coast of Africa hosts at least 12,000 plant species and 700 vertebrate species, 80% to 90% of which are found nowhere else on Earth. </p>
<p>Isolated for the last 88 million years and covering an area approximately the size of the <a href="https://www.mylifeelsewhere.com/country-size-comparison/united-states/madagascar">northeastern United States</a>, Madagascar is one of the world’s hottest biodiversity hotspots. Its island-wide species diversity is striking, but its tropical forest biodiversity is truly exceptional.</p>
<p>Sadly, human activities are ravaging tropical forests worldwide. Habitat fragmentation, over-harvesting of wood and other forest products, over-hunting, invasive species, pollution and climate change are depleting many of these forests’ native species.</p>
<p>Among these threats, climate change receives special attention because of its global reach. But in my research, I have found that in Madagascar it is not the dominant reason for species decline, although of course it’s an important long-term factor. </p>
<p>As a <a href="https://scholar.google.com/citations?user=JltJlTAAAAAJ&hl=en">primatologist and lemur specialist</a>, I study how human pressures affect Madagascar’s highly diverse and endemic signature species. In two recent studies, colleagues and I have found that in particular, the <a href="http://pin.primate.wisc.edu/factsheets/entry/ruffed_lemur">ruffed lemur</a> – an important seed disperser and indicator of rainforest health – is being disproportionately impacted by human activities. Importantly, habitat loss is driving ruffed lemurs’ distributions and genetic health. These findings will be key to helping save them. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/305976/original/file-20191209-90552-1h12vkc.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/305976/original/file-20191209-90552-1h12vkc.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/305976/original/file-20191209-90552-1h12vkc.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/305976/original/file-20191209-90552-1h12vkc.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/305976/original/file-20191209-90552-1h12vkc.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/305976/original/file-20191209-90552-1h12vkc.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/305976/original/file-20191209-90552-1h12vkc.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/305976/original/file-20191209-90552-1h12vkc.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Deforestation from slash-and-burn agriculture in the peripheral zones of Ranomafana National Park, Madagascar.</span>
<span class="attribution"><span class="source">Nina Beeby/Ranomafana Ruffed Lemur Project</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<h2>The forest is disappearing</h2>
<p>Madagascar has lost nearly half (44%) of its forests <a href="https://doi.org/10.1016/j.biocon.2018.04.008">within the last 60 years</a>, largely due to slash-and-burn agriculture – known locally as “tavy” – and charcoal production. Habitat loss and fragmentation <a href="https://doi.org/10.1111/mec.14173">runs throughout Madagascar’s history</a>, and the rates of change are staggering. </p>
<p>This destruction threatens Madagascar’s biodiversity and its human population. Nearly 50% of the country’s <a href="http://Globalforestwatch.org">remaining forest</a> is now located <a href="https://doi.org/10.1016/j.biocon.2018.04.008">within 300 feet (100 meters) of an unforested area</a>. Deforestation, illegal hunting and collection for the pet trade are pushing many species toward the <a href="http://dx.doi.org/10.1126/science.1245783">brink of extinction</a>.</p>
<p>In fact, the International Union for Conservation of Nature estimates that 95% of Madagascar’s lemurs are <a href="https://blogs.scientificamerican.com/extinction-countdown/lemurs-in-crisis-105-species-now-threatened-with-extinction/">now threatened</a>, making them the world’s <a href="https://www.livescience.com/21592-madagascar-lemurs-endangered.html">most endangered mammals</a>. Pressure on Madagascar’s biodiversity has <a href="https://doi.org/10.1038/s41893-019-0288-0">significantly increased over the last decade</a>.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/304797/original/file-20191202-66990-odnv25.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/304797/original/file-20191202-66990-odnv25.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/304797/original/file-20191202-66990-odnv25.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/304797/original/file-20191202-66990-odnv25.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/304797/original/file-20191202-66990-odnv25.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/304797/original/file-20191202-66990-odnv25.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/304797/original/file-20191202-66990-odnv25.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/304797/original/file-20191202-66990-odnv25.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">A red ruffed lemur, one of two <em>Varecia</em> species endemic to Madagascar.</span>
<span class="attribution"><span class="source">Varecia Garbutt</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<h2>Deforestation threatens ruffed lemur survival</h2>
<p>In a newly published study, climate scientist <a href="https://scholar.google.com/citations?user=b24cai8AAAAJ&hl=en&oi=ao">Toni Lyn Morelli</a>, species distribution expert <a href="https://scholar.google.com/citations?user=_vVCUiIAAAAJ&hl=en&oi=ao">Adam Smith</a> and I worked with 19 other researchers to study how <a href="http://dx.doi.org/10.1038/s41558-019-0647-x">deforestation and climate change</a> will affect two critically endangered ruffed lemur species over the next century. Using combinations of different deforestation and climate change scenarios, we estimate that suitable rainforest habitat could be reduced by as much as 93%. </p>
<p>If left unchecked, deforestation alone could effectively eliminate ruffed lemurs’ entire eastern rainforest habitat and with it, the animals themselves. In sum, for these lemurs the effects of forest loss will outpace climate change. </p>
<p>But we also found that if current protected areas lose no more forest, climate change and deforestation outside of parks will reduce suitable habitat by only 62%. This means that maintaining and enhancing the integrity of protected areas will be essential for saving Madagascar’s rainforest habitats.</p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/304790/original/file-20191202-66990-16m4zqe.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/304790/original/file-20191202-66990-16m4zqe.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/304790/original/file-20191202-66990-16m4zqe.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=1157&fit=crop&dpr=1 600w, https://images.theconversation.com/files/304790/original/file-20191202-66990-16m4zqe.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=1157&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/304790/original/file-20191202-66990-16m4zqe.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=1157&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/304790/original/file-20191202-66990-16m4zqe.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1454&fit=crop&dpr=1 754w, https://images.theconversation.com/files/304790/original/file-20191202-66990-16m4zqe.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1454&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/304790/original/file-20191202-66990-16m4zqe.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1454&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Warm colors indicate areas where lemurs can move about readily, which promotes genetic diversity; cool colors indicate areas where they are more constrained and less able to mate with members of other population groups.</span>
<span class="attribution"><a class="source" href="https://doi.org/10.1038/s41598-019-52689-2">Baden et al. (2019), Nature Scientific Reports</a>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<p>In a study published in November 2019, my colleagues and I showed that ruffed lemurs <a href="https://doi.org/10.1038/s41598-019-52689-2">depend on habitat cover to survive</a>. We investigated natural and human-caused impediments that prevent the lemurs from spreading across their range, and tracked the movement of their genes as they ranged between habitats and reproduced. This movement, known as gene flow, is important for maintaining genetic variability within populations, allowing lemurs to adapt to their ever-changing environments. </p>
<p>Based on this analysis, we parsed out which landscape variables – including rivers, elevation, roads, habitat quality and human population density – best explained gene flow in ruffed lemurs. We found that human activity was the best predictor of ruffed lemurs’ population structure and gene flow. Deforestation alongside human communities was the most significant barrier. </p>
<p>Taken together, these and other lines of evidence show that deforestation poses an imminent threat to conservation on Madagascar. Based on our projections, habitat loss is a more immediate threat to lemurs than climate change, at least in the immediate future. </p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/TxUPMzI14WY?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">In 1961 naturalist David Attenborough filmed ruffed lemurs for the BBC.</span></figcaption>
</figure>
<p>This matters not only for lemurs, but also for other plants and animals in the areas where lemurs are found. The same is true at the global level: More than one-third (about 36.5%) of Earth’s plant species are <a href="http://dx.doi.org/10.1126/sciadv.aaz0414">exceedingly rare</a> and disproportionately affected by human use of land. Regions where the most rare species live are experiencing higher levels of human impact. </p>
<h2>Crisis can drive conservation</h2>
<p>Scientists have warned that the fate of Madagascar’s rich natural heritage <a href="https://doi.org/10.1038/s41893-019-0288-0">hangs in the balance</a>. Results from our work suggest that strengthening protected areas and reforestation efforts will help to mitigate this devastation while environmentalists work toward long-term solutions for curbing the runaway greenhouse gas emissions that drive climate change. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/305974/original/file-20191209-90592-h4v45g.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/305974/original/file-20191209-90592-h4v45g.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/305974/original/file-20191209-90592-h4v45g.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=401&fit=crop&dpr=1 600w, https://images.theconversation.com/files/305974/original/file-20191209-90592-h4v45g.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=401&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/305974/original/file-20191209-90592-h4v45g.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=401&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/305974/original/file-20191209-90592-h4v45g.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=504&fit=crop&dpr=1 754w, https://images.theconversation.com/files/305974/original/file-20191209-90592-h4v45g.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=504&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/305974/original/file-20191209-90592-h4v45g.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=504&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">A young woman participates in reforestation efforts in Kianjavato, Madagascar.</span>
<span class="attribution"><span class="source">Brittani Robertson/Madagascar Biodiversity Partnership</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<p>Already, nonprofits are working hard toward these goals. A partnership between Dr. Edward E. Louis Jr., founder of <a href="https://madagascarpartnership.org">Madagascar Biodiversity Partnership</a> and director of Conservation Genetics at Omaha’s Henry Doorly Zoo, and the Arbor Day Foundation’s <a href="https://www.arborday.org/programs/rainforest/madagascar/">Plant Madagascar</a> project has replanted nearly 3 million trees throughout Kianjavato, one region identified by our study. Members of <a href="https://www.stonybrook.edu/commcms/centre-valbio/community_outreach/community.html">Centre ValBio’s reforestation team</a> – a nonprofit based just outside of Ranomafana National Park that facilitates our ruffed lemur research – are following suit.</p>
<p>At an international conference in Nairobi earlier this year, Madagascar’s president, Andry Rajoelina, promised to <a href="https://www.oneplanetsummit.fr/en">reforest 40,000 hectares (99,000 acres) every year</a> for the next five years – the equivalent of 75,000 football fields. This commitment, while encouraging, unfortunately <a href="https://news.mongabay.com/2019/11/madagascars-bold-reforestation-goal-lacks-a-coherent-plan-experts-say/">lacks a coherent implementation plan</a>. </p>
<p>Our projections highlight areas of habitat persistence, as well as areas where ruffed lemurs could experience near-complete habitat loss or genetic isolation in the not-so-distant future. Lemurs are an effective indicator of total <a href="https://doi.org/10.1371/journal.pone.0136787">non-primate community richness</a> in Madagascar, which is another way of saying that protecting lemurs will protect biodiversity. Our results can help pinpoint where to start.</p>
<p>[ <em>Like what you’ve read? Want more?</em> <a href="https://theconversation.com/us/newsletters?utm_source=TCUS&utm_medium=inline-link&utm_campaign=newsletter-text&utm_content=likethis">Sign up for The Conversation’s daily newsletter</a>. ]</p><img src="https://counter.theconversation.com/content/127878/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Andrea L. Baden receives funding from the National Science Foundation, The Leakey Foundation, J. William Fulbright Foundation, Primate Conservation, Inc., and the Margot Marsh Biodiversity Fund. She is affiliated with Hunter College of the City University of New York, The Graduate Center of the City University of New York, and the New York Consortium in Evolutionary Primatology, and is a Scientific Advisor for the Mangevo research site to the Centre ValBio Research Station.</span></em></p>New research shows that slowing deforestation is the most essential step for saving Madagascar’s lemurs, and can help protect them against the longer-term threat of climate change.Andrea L. Baden, Assistant Professor of Anthropology, Hunter CollegeLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1233122019-09-24T11:28:54Z2019-09-24T11:28:54ZHow fires weaken Amazon rainforests’ ability to bounce back<figure><img src="https://images.theconversation.com/files/292686/original/file-20190916-19030-1b1tueo.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Prescribed fires are often done to eliminate weeds and renew the grasses in pastures for ranching across the Amazon.</span> <span class="attribution"><span class="source">Paulo Massoca</span>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span></figcaption></figure><p>The flames consuming the Amazon rainforest this year have alarmed the world, renewing concerns about one of the planet’s most biodiverse regions and the release of large amounts of carbon into the atmosphere. But there’s another concern that’s been largely overlooked – the eroding capacity of Amazonian ecosystems to recover from repeated burning over the years.</p>
<p>The fires across the Amazon rainforest are due exclusively to human activities. Ranchers, farmers and <a href="https://pdfs.semanticscholar.org/41cd/638648e8210d0642bf76219ccefe5f0ab68b.pdf">land grabbers</a> use fire to clear land or renew pastures for ranching, while indigenous and local groups <a href="https://www.nationalgeographic.com/environment/2019/09/ancient-humans-burned-amazon-fires-today-entirely-different/">often use it</a> to fertilize and clear fields for traditional agriculture.</p>
<p>Some of these cleared areas are later abandoned and left to regrow – a potentially hopeful twist in the story. But the new forests don’t always simply pick up where the original ones left off. More than 20 years of <a href="https://www.researchgate.net/profile/Rita_Mesquita">study</a> at <a href="http://portal.inpa.gov.br/">Brazil’s Instituto Nacional de Pesquisas da Amazônia</a>, which we have contributed to, has shown that repeated use of fires to manage land results in forests that grow slowly and lose the capacity to restore biodiversity and store carbon.</p>
<h2>Rebounding forests</h2>
<p>Secondary forests, or forests that return after being cleared, today total 2.4 million square kilometers in Latin America. <a href="https://www.sciencedirect.com/science/article/pii/S0959378018302255">This regrowth</a> stems from migration from rural areas to cities, intensification of agriculture, and the abandonment of marginal lands among other reasons. </p>
<p><a href="https://link.springer.com/article/10.1007/s13280-016-0772-y">The return of trees is good news</a> in a region where primary tropical forests are quickly being destroyed, because the returning forests can have significant local and global ecological benefits. </p>
<p>In only 20 years they can <a href="https://advances.sciencemag.org/content/5/3/eaau3114.full">harbor some 80% of the tree species</a> found in surrounding mature forests, helping restore biodiversity. They can also sequester <a href="http://www.doi.org/10.1126/sciadv.1501639">massive amounts of carbon</a>. In addition, secondary forests provide a natural corridor for animals living in increasingly fragmented rural landscapes.</p>
<p>These secondary forests also protect and restore soils, replenish watersheds, and benefit people whose livelihoods depend on them for food, wood and other goods. </p>
<p>So it’s not surprising that letting forests regrow has gained traction as a low-cost and effective way to restore ecosystems and help curb climate change. But those potential benefits are hardly universal, as our research has shown.</p>
<h2>The persistent impact of fires in forest recovery</h2>
<p>Across different sites in the Central Amazon, we have studied how forests regrow spontaneously in lands abandoned after different land uses and fire histories. </p>
<p>One typical example of such use is cattle ranching on former forest land. After an initial clearing by cutting and burning, ranchers usually use fire every one to two years to remove weeds and renew the grass. Another is shifting cultivation, in which millions of Amazonians use alternating cycles of cutting, burning, cultivation and regrowth to produce local staples. </p>
<p><a href="https://doi.org/10.1111/brv.12343">As part of a long-term experiment</a>, <a href="https://doi.org/10.1093/biosci/biv108">we annually monitored</a> the process by which trees arrive, become established, grow and die after intact forests were cleared near the city of Manaus, Brazil. We and our collaborators found that two to eight years of pasture management with annual burning resulted in <a href="https://www.tandfonline.com/doi/abs/10.1080/17550874.2012.735714">forest stands markedly distinct</a> from those thriving in areas left alone soon after being cut. </p>
<p>Trees arrive and grow relatively quickly in both areas, and satellites can detect their crowns within three to five years. But the images from the sky do not distinguish the poor on-the-ground quality of secondary forests in areas that are repeatedly burned. <a href="https://besjournals.onlinelibrary.wiley.com/doi/10.1046/j.1365-2745.2001.00583.x">Once forests begin to grow back</a>, these areas are dominated by just a few species that exhibit an unusual resistance to fire and a high capacity to sprout.</p>
<iframe frameborder="0" class="juxtapose" width="100%" height="430" src="https://cdn.knightlab.com/libs/juxtapose/latest/embed/index.html?uid=c272d1e6-db4b-11e9-b9b8-0edaf8f81e27"></iframe>
<p><em>Stands of secondary forests regaining areas with distinct land use and fire history after five years since abandonment near the town of Tefé, Brazil. On the left, a closed understory with a richer community of trees regenerating in areas exposed to only one burning contrasts with an open understory and an impoverished forest stand dominated by one tree species over a field burned five times, on the right. (Photos: Catarina Jakovac</em>) </p>
<p>Recurrent burnings eliminate tree seeds from the soil, and new species dispersed from surrounding forests arrive at an extremely slow pace. The result is that after two decades, forests growing in fire-managed former pasturelands shelter some 50% fewer tree species than in secondary forests reclaiming areas not damaged by fire, the research shows.</p>
<p>The rate with which carbon is accumulated through plant growth also falls after each fire event; after five burnings, the <a href="https://esajournals.onlinelibrary.wiley.com/doi/10.1890/1540-9295%282005%29003%5B0365%3ALOFSCA%5D2.0.CO%3B2">rate of biomass recovery reduces 50%</a>.</p>
<h2>Pervasive impacts of fires on forest recovery</h2>
<p>The results we found in <a href="https://doi.org/10.1093/biosci/biv108">our research sites</a> around Manaus have also been seen in new studies carried out in non-experimental settings. In Apuí, an area in southern Amazonia suffering a <a href="https://g1.globo.com/am/amazonas/noticia/2019/08/30/apui-am-teve-526-focos-de-queimadas-nesta-semana-g1-sobrevoou-area-em-chamas.ghtml">high rate of recent deforestation and fire events</a>, years of cattle ranching and repeated burning have compromised the ability of secondary forests to thrive spontaneously in abandoned fields.</p>
<p>We have seen a <a href="https://besjournals.onlinelibrary.wiley.com/doi/epdf/10.1111/1365-2745.12298">similar pattern in once-traditional cultivation systems</a> <a href="https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0181092">as socio-economic changes have pushed these systems over their carrying capacity.</a> In the region of Tefé toward western Amazonia, the more times one field is cultivated and the shorter the fallow period between burnings, the more slowly secondary forests grow and the more they harbor a community of plants characterized by woody vines and trees similar to those found in abandoned cattle pasture. </p>
<p>This intensification of that traditional agricultural system is also reducing productivity by 30-50% and <a href="https://www.sciencedirect.com/science/article/pii/S0167880915301481">disrupting the sustainability of those landscapes</a>. And each new cycle of slash-and-burn decreases the amount of carbon these forests sequester by 10%.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/292084/original/file-20190911-190012-2ukws8.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/292084/original/file-20190911-190012-2ukws8.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/292084/original/file-20190911-190012-2ukws8.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/292084/original/file-20190911-190012-2ukws8.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/292084/original/file-20190911-190012-2ukws8.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/292084/original/file-20190911-190012-2ukws8.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=502&fit=crop&dpr=1 754w, https://images.theconversation.com/files/292084/original/file-20190911-190012-2ukws8.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=502&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/292084/original/file-20190911-190012-2ukws8.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=502&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">A field recently burned for crop cultivation under the traditional slash-and-burn system. Areas burned and cultivated more than four times under short fallow regimes of between four and seven years lead to secondary forests similar to those recovering from degraded pasturelands, with a low number of fire-resistant species and slow forest regrowth.</span>
<span class="attribution"><span class="source">Catarina Jakovac</span>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<p>These studies show that the impact of fire on forest regeneration and ecosystem recovery is not mitigated by natural processes for at least several decades. Depending on the frequency of burning events, the return of biodiversity and carbon stocks can be extremely slow or possibly never happen, even in areas bordering otherwise highly forested landscapes.</p>
<h2>Implications for decision-makers</h2>
<p><a href="http://www.bonnchallenge.org/content/challenge">Brazil has committed to restore 120,000 square kilometers of degraded lands by 2030</a> as part of a global effort to recover these areas. But our work suggests that the goal of sequestering more than 1 gigaton of CO2 and generating some $4 billion in economic benefits, as envisioned by <a href="http://www.bonnchallenge.org/content/brazil">Brazil’s targets</a>, can only be realized in nondegraded land, or areas not burned regularly. </p>
<iframe frameborder="0" class="juxtapose" width="100%" height="420" src="https://cdn.knightlab.com/libs/juxtapose/latest/embed/index.html?uid=7ffda836-da47-11e9-b9b8-0edaf8f81e27"></iframe>
<p><em>Secondary forests recovering deforested areas in the Brazilian Amazon as of 2014. Some 170,000 sq. km – an area the size of Florida – is re-greening abandoned lands. But half of the secondary forests are recovering former pastures. (Source: TerraClass)</em></p>
<p>Roughly one-third of the secondary forests in the Amazon are growing over abandoned pasture and agricultural lands. But the pervasive use of fire and fallow periods of less than five years hinder the natural trajectory of forest succession in those areas. Once abandoned, these impoverished forest landscapes become trapped in a steady state that may persist for decades. They grow at a slow pace, harbor a limited number of species, <a href="https://www.sciencedirect.com/science/article/pii/S0378112715001498">sequester carbon at low rates,</a> and are of little use for local people’s livelihoods.</p>
<p>If the government of Brazil does want to effectively <a href="https://royalsocietypublishing.org/doi/full/10.1098/rspb.2017.2577">recover deforested lands</a>, it must take active steps to help secondary forests to thrive in such contexts. Two decades of research shows government support and investments in <a href="https://aliancaamazonia.org.br/en/">restoration initiatives</a> such as <a href="https://www.sciencedirect.com/science/article/pii/S0378112717301299?via%3Dihub">tree pruning</a>, seedling plantation, soil recovery and agroforestry are required if recovering forests in the Amazon are to have any real economic or ecological value to future generations of humans and the planet.</p>
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<p class="fine-print"><em><span>Paulo Massoca is an Ostrom Workshop fellow and had a Sciences without Borders program scholarship (CNPq/Brazil) while in the Center for the Analysis of Social-Ecological Landscapes (CASEL) at Indiana University. </span></em></p><p class="fine-print"><em><span>Catarina Conte Jakovac works for Wageningen University, The Netherlands, and for the International Institute for Sustainability, Brazil.</span></em></p>Reversing the damage from fires in Brazil’s rainforest is not as simple as allowing trees to grow back. Decades of research shows how fires degrade their long-term health and utility.Paulo Massoca, Ph.D. candidate, Indiana UniversityCatarina Conte Jakovac, Postdoctoral researcher, Wageningen UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1228402019-09-09T11:35:15Z2019-09-09T11:35:15ZIn Brazil’s rainforests, the worst fires are likely still to come<p>The number of fires this year in the Amazon is the <a href="https://uk.reuters.com/article/us-brazil-environment/brazil-deforestation-rises-in-august-adding-to-amazon-fire-worries-idUKKCN1VR1R8">highest since 2010</a>, reaching more than <a href="http://queimadas.dgi.inpe.br/queimadas/portal-static/situacao-atual/">90,000 active fires</a>. Farmers and ranchers routinely use fires to clear the forest. But this year’s number reflects a worrisome uptick in the rate of deforestation, which had started to drop <a href="https://rainforests.mongabay.com/amazon/deforestation_calculations.html">around 2005</a> before rebounding earlier this decade.</p>
<p>Many people <a href="https://www.telegraph.co.uk/news/2019/08/23/wont-get-trouble-jair-bolsonaros-pledges-prospectors-blamed/">blame the Brazilian government</a> and its pro-agriculture policies for the current crisis. But as an <a href="https://scholar.google.com/citations?user=PTEKYYoAAAAJ&hl=en">environmental researcher</a> who has worked in the Amazon for the past 25 years, I can say the seeds were planted before the election of President Jair Bolsonaro in 2018. And the prospects of slowing deforestation remain dim, an issue that matters to people around the world.</p>
<p>That’s in part because the current administration has only aggravated the situation with its anti-environmental agenda. Unless the Brazilian people <a href="https://www.npr.org/2019/08/26/754292402/sos-from-brazils-amazon-fire-protesters-we-need-the-world-s-help-right-now">succeed</a> in making Bolsonaro retreat from his stated goal of developing the Amazon, deforestation will surge again. Adding fuel to the fire is the quickening pace of the Initiative for the Integration of the Regional Infrastructure of South America (<a href="https://www.internationalrivers.org/campaigns/initiative-for-the-integration-of-regional-infrastructure-in-south-america">IIRSA</a>), a multi-nation <a href="https://doi.org/10.1111/btp.12610">plan</a> to build road, dams and rail lines across the Amazon. </p>
<h2>Conflicting objectives</h2>
<p>Brazil managed to significantly reduce deforestation rates at the turn of the millennium with <a href="https://doi.org/10.1126/science.1248525">effective environmental policy and voluntary efforts by the private sector</a>. Deforestation, which <a href="https://rainforests.mongabay.com/amazon/deforestation-rate.html">started in the 1970s</a>, began climbing again in 2015 due to political turmoil and an economic recession that paved the way to <a href="https://doi.org/10.1038/s41893-018-0179-9">policy reversals</a>.</p>
<p>The <a href="https://rainforests.mongabay.com/amazon/deforestation-rate.html">Amazonian deforestation rate</a> dropped from about 10,700 square miles in 2004 to 1,765 square miles in 2012, and remained low until its <a href="https://theconversation.com/amazon-deforestation-already-rising-may-spike-under-bolsonaro-109940">resurgence a few years ago</a>. This was because of effective environmental policy, which in Brazil is mostly based on protected areas, such as national parks, and a forestry code limiting the amount of land that can be cleared on individual properties. </p>
<p><iframe id="EmlT2" class="tc-infographic-datawrapper" src="https://datawrapper.dwcdn.net/EmlT2/1/" height="400px" width="100%" style="border: none" frameborder="0"></iframe></p>
<p>Over the years, the Brazilian government has developed a system of protected areas for ecological protection and indigenous reserves. In 2002 it expanded their coverage to about <a href="https://doi.org/10.1073/pnas.0806059106">43% of the entire Amazon</a>. It also created protected areas in zones of land conflict as a means to <a href="https://doi.org/10.1038/s41893-018-0179-9">tamp down rampant fire and deforestation</a>. </p>
<p>Adding to this, enforcement of the forestry code was enhanced by the development of a satellite monitoring system that enabled Brazil’s environmental protection agency to <a href="https://doi.org/10.1016/j.landusepol.2014.06.026">identify law-breaking property owners from space</a>. In addition to government, the private sector helped lower the rate of deforestation. Soybean farmers stopped planting new fields in the forest, and retailers demanded that the goods they sold come from lands already cleared so they could <a href="https://doi.org/10.1126/science.aaa0181">certify them as “green,” especially beef</a>.</p>
<p>Unfortunately, these efforts began to unravel almost as soon as they proved themselves effective. The background reason is that many people have long viewed the Amazon as a vast store of valuable resources to be used for the <a href="https://biblioteca.ibge.gov.br/biblioteca-catalogo.html?id=29613&view=detalhes">economic development</a> of a poor region. The agenda of <a href="http://www.iirsa.org/">IIRSA</a> – an extensive infrastructure building project launched in 2000 to link the region’s economies and remote areas – <a href="https://www.tandfonline.com/doi/pdf/10.1080/00139157.2018.1418994">expresses this view</a>, common to all nations that share the Amazon Basin. These include, in addition to Brazil, Bolivia, Colombia, Ecuador, Guyana, Peru, Suriname and Venezuela. It should come as no surprise that their individual orientations to the region all reflect a contradiction between economic development on the one hand and conservation on the other. </p>
<p>In Brazil, the government not only creates protected areas, it downsizes them in order to <a href="https://conbio.onlinelibrary.wiley.com/doi/full/10.1111/cobi.12298">prepare for infrastructure projects</a>. Former President Dilma Rousseff even downsized Amazon National Park in 2012, the first in the Amazon, to make way for the Tapajós Hydroelectric Complex, a <a href="https://doi.org/10.1353/lag.2016.0013">key component of the IIRSA plan</a>. The government does not act in a vacuum, and in Brazil a powerful congressional bloc, the rural/mining caucus known as the Ruralistas, works tirelessly at <a href="https://doi.org/10.1038/s41558-018-0213-y">undermining environmental policy</a>.</p>
<p>This has led to revisions in the forestry code, in 2012, that <a href="https://www.wilsoncenter.org/article/environmental-concerns-brazil-2018-understanding-the-issues">favor agriculture, not the environment,</a> by exempting those who illegally deforested before 2008 from having to reforest in <a href="https://doi.org/10.1038/s41893-018-0179-9">accordance with the law</a>. Continuing Ruralista political action made it easier in 2017 for land grabbers to <a href="https://doi.org/10.1038/s41558-018-0213-y">obtain title to illegally seized lands</a>.</p>
<iframe frameborder="0" class="juxtapose" width="100%" height="420" src="https://cdn.knightlab.com/libs/juxtapose/latest/embed/index.html?uid=6476e4c0-d186-11e9-b9b8-0edaf8f81e27"> </iframe>
<p><em>Two images from the same 10 kilometer square area in Brazil reflect how cleared land replaces the forest in the Amazon.</em></p>
<h2>Fears of a tipping point</h2>
<p>President Bolsonaro has inherited a set of weakened environmental policies and all indications are that he will continue to weaken them. At the same time, he has acted on his promise to open the Amazon to development by <a href="https://www.businessinsider.com/bolsonaro-plan-to-develop-amazon-rainforest-2019-1">announcing plans</a> to build a bridge across the Amazon River and to extend a paved road all the way to the border with Suriname. The IIRSA agenda appears to be accelerating, and as <a href="https://www.cbsnews.com/news/amazon-rainforest-fires-ranchers-blamed-for-deforestation-in-brazil-rely-on-booming-business-2019-08-29/">people flock to the region</a> to take advantage of the <a href="https://pdfs.semanticscholar.org/ceb9/8413e8744fd56c676d3e71e47c45166ee1c5.pdf">jobs it creates</a>, the <a href="https://doi.org/10.1111/j.1467-9787.2007.00519.x">fires can only get worse</a>.</p>
<p>Since the opening of the <a href="https://www.tandfonline.com/doi/full/10.1080/24694452.2018.1489215">Amazon to development in the 1970s</a>, fires have been deliberately set on a yearly basis to make way for fields and pastures and to fertilize soils. The Amazon maintains a moist climate, which limits their extent. Thus, super fires have never raged over hundreds of square miles as happens with wildfires in the U.S. But this could change due to the <a href="https://doi.org/10.1890/14-1528.1">cumulative effect of the repeated use of fire</a>.</p>
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<iframe width="440" height="260" src="https://www.youtube.com/embed/2yMnMJWyY7k?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
</figure>
<p>Research shows that every year when the forest burns, <a href="https://doi.org/10.1038/nature01437">the destructive effect spreads</a> beyond the flames to kill trees and desiccate the landscape. This can make the forest ever more vulnerable to fire through the <a href="https://conbio.onlinelibrary.wiley.com/doi/full/10.1046/j.1523-1739.2001.01093.x">buildup of flammable materials</a> and the coalescence of fire-scarred ecosystems across <a href="https://doi.org/10.1098/rstb.2007.0036">broad swaths of the entire basin</a>.</p>
<p>If Brazil does not retreat from the course it is on, scientists warn there will come a time in the near future when Amazonian <a href="https://theconversation.com/amazon-fires-what-will-happen-if-they-keep-burning-122758">fires burn without control</a> and push the forest to a point of no return, what some have called a “<a href="https://e360.yale.edu/features/will-deforestation-and-warming-push-the-amazon-to-a-tipping-point?">tipping point</a>” that will <a href="https://doi.org/10.1126/sciadv.aat2340">permanently change</a> the <a href="https://doi.org/10.1016/j.cosust.2009.07.003">underlying ecosystem</a>. Without a restoration of environmental policy in Brazil, the worst fires are yet to come.</p>
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<p class="fine-print"><em><span>Robert T. Walker has received funding in the past from the National Science Foundation to conduct research in the Brazilian Amazon. The views he expresses do not necessarily reflect those of the Foundation.</span></em></p>As deforestation rates in Brazil rise, it’s worth asking whether the country can repeat the successes of the last decade. Current trends don’t bode well.Robert T. Walker, Professor of Latin American Studies and Geography, University of FloridaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1195082019-07-03T18:07:20Z2019-07-03T18:07:20ZHigh-value opportunities exist to restore tropical rainforests around the world – here’s how we mapped them<figure><img src="https://images.theconversation.com/files/281981/original/file-20190701-105168-12ajqfm.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Forest restoration is underway in Biliran, Leyte, Philippines led by the local community with support from international researchers and government agencies.
</span> <span class="attribution"><span class="source">Robin Chazdon</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span></figcaption></figure><p>The green belt of tropical rainforests that covers equatorial regions of the Americas, Africa, Indonesia and Southeast Asia is turning brown. Since 1990, <a href="https://www.oneearth.org/protecting-50-of-our-lands-and-oceans/">Indonesia has lost 50% of its original forest, the Amazon 30% and Central Africa 14%</a>. Fires, logging, hunting, road building and fragmentation have heavily damaged <a href="http://dx.doi.org/10.1126/science.aaa9932">more than 30% of those that remain</a>.</p>
<p>These forests <a href="https://dx.doi.org/10.1038/s41559-018-0490-x">provide many benefits</a>: They store large amounts of carbon, are home to numerous wild species, provide food and fuel for local people, purify water supplies and improve air quality. Replenishing them is an urgent global imperative. A newly published study in the journal Science by European authors finds that there is room for <a href="http://dx.doi.org/10.1126/science.aax0848">an extra 3.4 million square miles (0.9 billion hectares) of canopy cover</a> around the world, and that replenishing tree cover at this full potential would contribute significantly to reducing the risk of harmful climate change</p>
<p>But there aren’t enough resources to restore all tropical forests that have been lost or damaged. And restoration can conflict with other activities, such as farming and forestry. As a <a href="https://scholar.google.com/citations?user=utgfbkgAAAAJ&hl=en">tropical forest ecologist</a>, I am interested in developing better tools for assessing where these efforts will be most cost-effective and beneficial. </p>
<p>Over the past four years, tropical forestry professor <a href="https://scholar.google.com.br/citations?user=0f_YV1wAAAAJ&hl=en">Pedro Brancalion</a> and I have led a team of researchers from <a href="https://partners-rcn.org/">an international network</a> in evaluating the benefits and feasibility of restoration across tropical rainforests around the world. Our newly published findings <a href="https://advances.sciencemag.org/content/5/7/eaav3223">identify restoration hotspots</a> – areas where restoring tropical forests would be most beneficial and least costly and risky. They cover over 385,000 square miles (100 million hectares), an area as large as Spain and Sweden combined. </p>
<p>The five countries with the largest areas of restoration hotpots are Brazil, Indonesia, India, Madagascar and Colombia. Six countries in Africa – Rwanda, Uganda, Burundi, Togo, South Sudan and Madagascar – hold rainforest areas where restoration is expected to yield the highest benefits with the highest feasibility. We hope our results can help governments, conservation groups and international funders target areas where there is high potential for success.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/282122/original/file-20190702-105200-b75gbp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/282122/original/file-20190702-105200-b75gbp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/282122/original/file-20190702-105200-b75gbp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=481&fit=crop&dpr=1 600w, https://images.theconversation.com/files/282122/original/file-20190702-105200-b75gbp.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=481&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/282122/original/file-20190702-105200-b75gbp.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=481&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/282122/original/file-20190702-105200-b75gbp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=605&fit=crop&dpr=1 754w, https://images.theconversation.com/files/282122/original/file-20190702-105200-b75gbp.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=605&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/282122/original/file-20190702-105200-b75gbp.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=605&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">A native tree nursery for large-scale restoration of Atlantic Forest at Reserva Natural Guapiaçu, Rio de Janeiro State, Brazil.</span>
<span class="attribution"><span class="source">Robin Chazdon</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<h2>Where to start</h2>
<p><a href="http://dx.doi.org/10.1126/sciadv.1600821">Intact forest landscapes</a> in tropical regions declined by 7.2% from 2000 to 2013, mainly due to logging, clearing and fires. These losses have <a href="https://doi.org/10.1038/nature23285">dire consequences</a> for global biodiversity, climate change and forest-dependent peoples. </p>
<p>As my work has shown, <a href="https://www.press.uchicago.edu/ucp/books/book/chicago/S/bo17407876.html">tropical forests can recover</a> after they have been cleared or damaged. Although these second-growth forests will never perfectly replace the older forests that have been lost, planting carefully selected trees and assisting natural recovery processes can restore many of their former properties and functions.</p>
<p>But restoration is not uniformly feasible or desirable, and the benefits that forests provide are not evenly distributed. To make informed choices about restoration efforts and investments, organizations need more detailed spatial information. Existing <a href="https://www.wri.org/resources/maps/atlas-forest-and-landscape-restoration-opportunities">global maps of restoration opportunities</a> are based on actual versus potential levels of tree canopy cover. We wanted to go beyond this measurement to identify where the greatest potential payoffs and challenges lay. </p>
<p>Our study used high-resolution satellite imagery and the latest peer-reviewed research to integrate information about four benefits from forest restoration: biodiversity conservation, climate change mitigation, climate change adaptation and water security. We also assessed three aspects of feasibility: cost, investment risk and the likelihood of restored forests surviving into the future. </p>
<p>We studied these variables across all lowland tropical moist forests worldwide, dividing them into 1-kilometer square blocks that had lost more than 10% of their tree canopy cover in 2016. Each of the seven factors we studied had equal weight in our calculation of total restoration opportunity scores. </p>
<p>The top-scoring blocks, which we call “restoration hotspots,” represent the most compelling regions for tropical forest restoration, with maximum overall benefits and minimal negative trade-offs.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/b-U77ZgVOsg?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Forest restoration involves much more than planting trees.</span></figcaption>
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<h2>Forest restoration aligns with other global pledges</h2>
<p>The top 15 countries with the largest areas of restoration hotspots are distributed across all tropical rainforest regions around the world. Three are in Central and South America, five are in Africa and the Middle East, and seven are in Asia and the Pacific.</p>
<p>Importantly, 89% of the hotspots we identified were located within areas that have already been identified as <a href="http://wedocs.unep.org/bitstream/handle/20.500.11822/18446/Biodiversity_hotspots_for_conservation_priorit.pdf?sequence=1&isAllowed=y">biodiversity conservation hotspots</a> in tropical regions. These conservation hotspots have exceptionally high concentrations of at-risk species. They have been been focal areas for investment and activities to promote biodiversity conservation for nearly 20 years. </p>
<p>This finding makes sense, since two criteria for designating conservation hotspots – high rates of forest loss and high concentration of endemic, or locally distributed, species – were also variables in our study. Our results strongly support the need to develop and implement integrated solutions that protect remaining forest ecosystems and restore new forests within these high-priority regions. </p>
<p>We also found that 73% of tropical forest restoration hotspots are in countries that have made commitments under the <a href="http://www.bonnchallenge.org/content/challenge">Bonn Challenge</a>, a global effort to bring some 580,000 square miles (150 million hectares) of the world’s deforested and damaged land into restoration by 2020, and 1.35 million square miles (350 million hectares) by 2030. By making these pledges, Bonn Challenge participants have shown that they are politically motivated to restore and conserve forests, and are looking for restoration opportunities. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/282123/original/file-20190702-105206-zmimgi.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/282123/original/file-20190702-105206-zmimgi.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/282123/original/file-20190702-105206-zmimgi.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/282123/original/file-20190702-105206-zmimgi.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/282123/original/file-20190702-105206-zmimgi.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/282123/original/file-20190702-105206-zmimgi.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/282123/original/file-20190702-105206-zmimgi.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/282123/original/file-20190702-105206-zmimgi.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Forest restoration on small farms bordering Mpanga Forest Reserve, Uganda, can bring high levels of benefits and is relatively feasible to achieve.</span>
<span class="attribution"><span class="source">Robin Chazdon</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<h2>A means toward many ends</h2>
<p>The 88% of the lands we analyzed that did not qualify as restoration hotspots also deserve careful attention. These landscapes could be prioritized for restoration interventions that increase food, water and fuel security through agroforestry practices, watershed protection, woodlots for producing firewood and local timber or commercial tree plantations. All of these areas can provide benefits for people and the environment through combinations of different restoration approaches, even if they are not the best candidates for a full-scale effort to restore a high-functioning forest. </p>
<p>Forest restoration is also urgently needed in other types of forests across the world, such as seasonally dry tropical forests and temperate forests that are heavily managed for timber. Identifying key restoration opportunities in these regions requires separate studies based on their unique benefits and challenges. </p>
<p>Our study helps to highlight how restoring tropical forests can provide multiple benefits for people and nature, and aligns with existing conservation and sustainable development agendas, as discussed in a <a href="http://dx.doi.org/10.1126/science.aax9539">newly published perspective</a> related to the new findings in Science. We hope that our map of restoration opportunities and hotspots will provide useful guidance for nations, conservation organizations and funders, and that local communities and organizations will be engaged in and benefit from these efforts. </p>
<p>[ <em><a href="https://theconversation.com/us/newsletters?utm_source=TCUS&utm_medium=inline-link&utm_campaign=newsletter-text&utm_content=expertise">Expertise in your inbox. Sign up for The Conversation’s newsletter and get a digest of academic takes on today’s news, every day.</a></em> ]</p><img src="https://counter.theconversation.com/content/119508/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Robin Chazdon receives funding from the US National Science Foundation.</span></em></p>Restoring tropical rainforests is good for the climate, wild species and humans. But where to start? A new study pinpoints locations that will maximize benefits and minimize negative impacts.Robin Chazdon, Professor Emerita of Ecology and Evolutionary Biology, University of ConnecticutLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1057892018-11-05T11:43:58Z2018-11-05T11:43:58ZStrict Amazon protections made Brazilian farmers more productive, new research shows<p><em><a href="https://theconversation.com/la-proteccion-estricta-del-amazonas-fomenta-la-productividad-agricola-en-brasil-106488">Leer en español</a></em>.</p>
<p>Jair Bolsonaro, <a href="https://theconversation.com/what-bolsonaros-presidency-means-for-brazil-5-essential-reads-105894">Brazil’s new president</a>, will make many decisions during his four-year term, from combating violence to stimulating a stagnant economy. </p>
<p>Those decisions will have large impacts on Brazilians, who remain deeply divided over the controversial election of this <a href="https://theconversation.com/bolsonaro-wins-brazil-election-promises-to-purge-leftists-from-country-105481">far-right populist</a>.</p>
<p>But some of Bolsonaro’s decisions will affect the entire world, namely his promises to cut environmental protections in the Brazilian Amazon.</p>
<h2>The Amazon’s uncertain fate</h2>
<p>The Amazon is the world’s largest tropical rainforest and a <a href="https://e360.yale.edu/features/global_commodities_boom_fuels_new_assault_on_amazon">major global food exporter</a>. </p>
<p>The Amazon Basin also provides the rains that nourish Brazil’s productive croplands to the south, a <a href="https://www.reuters.com/article/us-brazil-farming-factbox-idUSTRE78M5HS20110923">breadbasket for the world</a>. The rainforest’s destruction could cause large-scale droughts in Brazil, leading to <a href="https://www.sciencedirect.com/science/article/pii/S0921800917306468">nationwide crop losses</a>.</p>
<p>An estimated 9 percent of Amazonian forests disappeared between 1985 and 2017, reducing the rainforest’s ability to <a href="https://www.theguardian.com/environment/2017/sep/28/alarm-as-study-reveals-worlds-tropical-forests-are-huge-carbon-emission-source">absorb the carbon emissions</a> that drive climate change.</p>
<p>Deforestation is <a href="http://science.sciencemag.org/content/sci/361/6407/1108.full.pdf">largely due to land clearing for agricultural purposes</a>, particularly cattle ranching. </p>
<p>Cattle production has an extremely <a href="https://theconversation.com/for-cattle-farmers-in-the-brazilian-amazon-money-cant-buy-happiness-85349">low profit margin</a> in the Brazilian Amazon. It also requires a massive amount of land for grazing. Both factors drive Amazonian farmers to continuously clear forest – illegally – to expand pastureland.</p>
<p>Today, <a href="http://mapbiomas.org/">12 percent of the Brazilian Amazon</a>, or 93 million acres – an area roughly the size of Montana – is used for agriculture, primarily cattle ranching but also soybean production. </p>
<p>Deforestation decreased substantially from 2004 to 2014 thanks to <a href="https://www.economist.com/science-and-technology/2014/06/05/cutting-down-on-cutting-down">strict environmental protections</a> passed by President Luiz Inácio Lula da Silva in 2004. His Workers Party cracked down on illegal land clearing in the Amazon, making Brazil a world leader in rainforest protection.</p>
<p>But deforestation in the Amazon has <a href="https://www.wri.org/blog/2016/12/brazilian-government-announces-29-percent-rise-deforestation-2016">begun to climb</a> again recently. </p>
<p>Brazilian President Michel Temer, a conservative who entered office in 2016 during a deep recession, has <a href="https://www.reuters.com/article/us-brazil-politics-environment/brazil-home-of-amazon-rolls-back-environmental-protection-idUSKCN18B21P">loosened enforcement of federal anti-deforestation laws</a>, slashed the environmental ministry’s budget and <a href="https://theconversation.com/the-world-protests-as-amazon-forests-are-opened-to-mining-83034">opened the Amazon to mining</a>.</p>
<p>Satellite data reveal that between August 2017 to 2018, 1.1 million acres of Brazilian Amazonian forest were cleared – the <a href="https://news.mongabay.com/2018/09/ahead-of-election-deforestation-continues-to-climb-in-the-brazilian-amazon/">highest deforestation rate since 2007</a>.</p>
<figure class="align-right ">
<img alt="" src="https://images.theconversation.com/files/242635/original/file-20181028-7068-mxzwnx.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/242635/original/file-20181028-7068-mxzwnx.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=394&fit=crop&dpr=1 600w, https://images.theconversation.com/files/242635/original/file-20181028-7068-mxzwnx.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=394&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/242635/original/file-20181028-7068-mxzwnx.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=394&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/242635/original/file-20181028-7068-mxzwnx.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=495&fit=crop&dpr=1 754w, https://images.theconversation.com/files/242635/original/file-20181028-7068-mxzwnx.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=495&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/242635/original/file-20181028-7068-mxzwnx.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=495&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Brazil’s next president.</span>
<span class="attribution"><a class="source" href="http://www.apimages.com/metadata/Index/APTOPIX-Brazil-Elections/efee31dae3e24db782c3da83aef19893/4/0">AP Photo/Silvia izquierdo</a></span>
</figcaption>
</figure>
<p>President-elect Bolsonaro has promised to further slash environmental protections in Brazil, saying that federal conservation zones and hefty fines for cutting down trees <a href="http://news.trust.org//item/20181026090106-r6vs5/">hinder economic growth</a>. </p>
<p>Specific plans include <a href="https://www.nytimes.com/2018/10/17/climate/brazil-election-amazon-environment.html">eliminating protections for indigenous territories</a> that safeguard forests from private developers and <a href="https://uk.news.yahoo.com/exclusive-brazil-apos-leading-candidate-232002196.html?guccounter=1">reducing fines</a> for illegally clearing land. </p>
<p>Bolsonaro also wants to <a href="https://news.mongabay.com/2018/10/jair-bolsonaro-looming-threat-to-the-amazon-and-global-climate/">dismantle Brazil’s Ministry of the Environment</a>, which enforces environmental laws.</p>
<h2>Brazil’s agricultural innovations</h2>
<p>The president-elect’s deregulatory agenda is supported by the Bancada Ruralista, a powerful congressional caucus that <a href="https://news.mongabay.com/2016/12/temer-government-set-to-overthrow-brazils-environmental-agenda/">defends Brazilian agribusiness interests</a>. </p>
<p>Despite the lobby’s stance that regulation hurts business, Brazil’s strict environmental laws have actually helped Amazonian farmers, my <a href="https://www.sciencedirect.com/science/article/pii/S0959378017312669#.W8yp0HPwe_0.twitter">recent research</a> shows.</p>
<p>From 2004 to 2014, Brazil’s federal government employed a host of tactics to <a href="https://pdfs.semanticscholar.org/53a5/9c0ef21a0a748f02e26969df1ff9dbc249f2.pdf">reduce Amazonian farmers’ incentives</a> to clear land. It increased penalties for deforestation, making it far more expensive to create new grazing land. Simultaneously, it <a href="http://www.agricultura.gov.br/assuntos/sustentabilidade/plano-abc/historico">offered state-subsidized, low-interest financing</a> for farmers who adopted more sustainable practices.</p>
<p>Those policies encouraged innovations that have made Amazon farmland much more productive. In a co-authored study <a href="https://www.sciencedirect.com/science/article/pii/S0959378017312669#.W8yp0HPwe_0.twitter">published in October in the journal Global Environmental Change</a>, my colleagues and I found that food production in the Amazon has substantially increased since 2004.</p>
<p>Amazonian farmers are now planting and harvesting two crops – mostly soybean and corn – each year, rather than just one. This is called “double cropping.” </p>
<p>Our study found that land in double cropping in Brazil’s most important agricultural state, Mato Grosso, increased from 840,000 acres in 2001 to more than 10.6 million acres in 2013, boosted by improved environmental laws. </p>
<h2>Farmers are getting richer</h2>
<p>Environmental regulation of the Brazilian Amazon has helped farmers improve business in other ways too, our research found. </p>
<p>Improved pasture management in Mato Grosso state led the number of cattle slaughtered annually per acre to double, meaning farmers are producing more meat – and therefore earning <a href="http://iopscience.iop.org/article/10.1088/1748-9326/aac4d1/meta">more money</a> – with their land. </p>
<p>Ranchers who add crops into pasture areas can <a href="http://iopscience.iop.org/article/10.1088/1748-9326/aac4d1/meta">more than quadruple</a> the amount of beef produced because cattle raised in integrated crop and livestock systems gain weight more quickly. That spares remaining Amazonian forests from deforestation.</p>
<p>These sustainable ranching practices also reduce the greenhouse gases associated with beef and leather production. Better nourished cows are slaughtered sooner, meaning <a href="https://theconversation.com/seaweed-could-hold-the-key-to-cutting-methane-emissions-from-cow-burps-66498">fewer burps per cow</a> per lifetime, leading to lower methane emissions. </p>
<p>Brazil’s progressive environmental protections have even pushed corporations that operate in the Amazon to adopt more sustainable practices. </p>
<p>Since 2006, hundreds of multinational food and timber companies, including Cargill and Nestle, have adopted “<a href="https://www.nature.com/articles/s41558-017-0061-1">zero-deforestation commitments</a>” – pledges that they will never again source products from farmers who continue to deforest their land.</p>
<p>The commitments started in the Brazilian Amazon and have since extended to <a href="http://forestdeclaration.org/goal/goal-2/">all forests on the planet</a>, including the <a href="https://www.ucsusa.org/global-warming/stop-deforestation/drivers-of-deforestation-2016-palm-oil#.W9ujHxNKjdQ">Indonesian and Malaysian rainforests</a>.</p>
<p>Brazilian law, which restricts Amazonian farmers from clearing more than 20 percent of their land and requires them to federally register their property for monitoring, has made it easier for zero-deforestation companies to drop producers who cut down trees.</p>
<h2>Saving the Amazon</h2>
<p>Strong environmental protections are necessary to save the Amazon, protecting Brazil and the world from the loss of this <a href="https://www.sciencedirect.com/science/article/pii/S0921800917306468">critical, fragile habitat</a>.</p>
<p>If Brazil’s next president dismantles its environmental laws, corporations could abandon their zero-deforestation standards in the Amazon. That could have ripple effects in other threatened habitats worldwide.</p>
<p>Far from being bad for business, Brazil’s Amazonian protections help sustain the country as a global breadbasket. </p>
<p>If Bolsonaro scraps them, he won’t just imperil a legendary rainforest. He’ll hurt Brazilian farmers, too – and the consumers worldwide who depend on them.</p><img src="https://counter.theconversation.com/content/105789/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Rachael Garrett has received funding from the Gordon and Betty Moore Foundation, the US National Science Foundation, and the US National Aeronautics and Space Agency.</span></em></p>Brazil’s president-elect wants to roll back environmental laws, saying they hurt rural growth. But preventing Amazonian deforestation has actually made farmland more productive.Rachael Garrett, Assistant Professor of the Human Dimensions of Global Change, Boston UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/987442018-06-29T09:04:57Z2018-06-29T09:04:57ZWhy we explored an undisturbed rainforest hidden on top of an African mountain<p>Atop Mount Lico in northern Mozambique is a site that few have had the pleasure of seeing – a <a href="https://earth.google.com/web/@-15.790833,37.3638889,1015.66649574a,5455.66522683d,35y,0h,45t,0r/data=Ck8aTRJFCiUweDE4Y2ZmZjQyMmM4MjYyM2Q6MHhmZmQxMzFhZWM0ZmU3NjBiGe4sMBrolC_AIU9wVumTrkJAKgpNb250ZSBMaWNvGAIgASgCKAI">hidden rainforest</a>, protected by a steep circle of rock. Though the mountain was known to locals, the forest itself remained a secret until six years ago, when Julian Bayliss spotted it on satellite imagery. It wasn’t until last year, however, that he revealed his discovery, at the <a href="http://www.bbowt.org.uk/events/2017/06/01/danger-and-discoveries-northern-mozambique">Oxford Nature Festival</a>.</p>
<p>We recently visited the 700 metre-high mountaintop rainforest in an expedition organised by Bayliss, in collaboration with Mozambique’s Natural History Museum and National Herbarium. As far as anyone knew (including the locals), we would be the first people to set foot there (spoiler: we weren’t).</p>
<p>Since the rainforest’s discovery, Lico has received <a href="https://www.theguardian.com/world/2018/jun/17/mozambique-mount-lico-rainforest-new-species">worldwide attention</a>. That it captured the public’s imagination speaks volumes about how rare such places are. Humans are nothing if not adventurous, pushing our range boundaries like no other species can. But when almost every corner of the planet now shows signs of human activity, how do conservation scientists justify visiting and publicising these last bastions of untrodden nature? </p>
<p>From our perspective, the answer depends on what expeditions like this can teach us about the natural world, our place in it, and how to shepherd the wildest of places through the <a href="https://www.nature.com/articles/nature14258">Anthropocene</a>. Standing back and crossing our collective fingers is not always a winning strategy. This expedition formed part of a <a href="https://www.cambridge.org/core/journals/oryx/article/discovery-biodiversity-and-conservation-of-mabu-forestthe-largest-mediumaltitude-rainforest-in-southern-africa/A1CD0A42708C5C2287FB8ABD808F36AC">long-standing research programme</a> into these mountains, that aims to provide evidence to legally protect Mozambique’s mountain forests. Currently none of northern Mozambique’s mountains are formally protected, either nationally or internationally. Finding new species is one way to highlight the importance of such sites and justify their protection.</p>
<p>As well as exploring Mount Lico, the expedition was the first to undertake a biological survey of nearby Mount Socone. Every bit as majestic and species rich as the iconic Lico, Socone highlights the <a href="https://www.youtube.com/watch?v=mni8mSS4KDU">threat faced by many forests in Mozambique</a>, Africa and elsewhere. Globally, one football pitch worth of forest <a href="https://www.theguardian.com/environment/ng-interactive/2018/jun/27/one-football-pitch-of-forest-lost-every-second-in-2017-data-reveals">is lost every second</a>, driving countless species to extinction. The removal of trees from mountain slopes also leads to soil erosion, flooding in the wet season and <a href="https://www.sciencedirect.com/science/article/pii/S2212041617305089">water shortages in the dry season</a>.</p>
<p>On our first day on Socone, we set out to locate the middle of the forest using a satellite image and GPS. However, the difference between what this image was telling us and what we could see was vast. As we walked towards what the image showed as the heart of lush rainforest, we could see the warm glow of the African sun. Soon enough, we emerged from beneath the canopy and into newly established farmland. Without the protective cover of the forest, heavy rains will pound these exposed mountain soils, fresh cuts will need to be made, and so the cycle repeats. Media attention on neighbouring Lico, and the new species descriptions coming out of both sites, help to bring these conservation and livelihood issues to the world’s attention.</p>
<h2>Time capsules</h2>
<p><a href="http://forestsfirstfootsteps.com/">Our brief footsteps on Lico</a> will soon be overgrown, and the plants and animals that live there will continue to be protected by the same towering cliffs (more than 125 metres high) that have saved them up to now (without the help of <a href="https://dmmclimbing.com/Journal/June-2018/Monte-Licos-rainforest-lost-world">world-class climbers</a>, our expedition would not have been possible).</p>
<p>But the impact of people goes far beyond where we have actually managed to set foot. Since the industrial revolution, humans have increased the amount of <a href="https://climate.nasa.gov/climate_resources/24/graphic-the-relentless-rise-of-carbon-dioxide/">carbon dioxide in the atmosphere</a> to levels higher than at any time in the past 400,000 years, <a href="https://www.ipcc.ch/report/ar5/">increasing temperatures and changing weather patterns</a>. Despite being situated on a fortress of rock, Lico’s forest is vulnerable to climate change, <a href="https://www.nature.com/articles/nature01286">like every other ecosystem on the planet</a>.</p>
<p>The contrast between protection from direct human activities but exposure to climate change means that Lico has a lot to teach us. Most forests experience both of these processes simultaneously, and so it is difficult to unravel their <a href="https://www.annualreviews.org/doi/abs/10.1146/annurev.ecolsys.39.110707.173345">relative and interacting impacts</a>. Through the data collected on Lico, Socone and other forests worldwide, we gain a greater understanding of how human disturbance affects the ability of forests to respond to environmental change.</p>
<p>Lico is a rare data point on this map: millennia of climate change and ecological response, played out in the absence of direct human disturbance. Reconstructing this history meant digging a two metre-deep pit in the forest, so that we could sample the layers of soil in the order that they accumulated. We tried to minimise any lasting effects on the forest (the hole was filled and topsoil replaced) but nonetheless, reasonable objections can be made against our disturbing this previously pristine site.</p>
<p>What we gained were a series of time capsules: each little tin of soil contains information on the plants that grew, the fires that burned and the water that flowed, data that will be shared in open access repositories, allowing people worldwide to investigate this unique site without the need for further disturbance. What we learn from Lico will help the world understand how forests might be affected by future changes in climate.</p>
<p>So were we really the first humans on Lico? Well, not quite. To everyone’s surprise, we found ancient pots, ceremonially placed near the source of a stream that flows to a waterfall down the side of the cliff. Were these placed there during a time of drought, as the waterfall ran dry and the crops failed? </p>
<p>Archaeologists and climate scientists are investigating. Given the pots pre-date local knowledge, the incredible inaccessibility and lack of any other signs of human activity, Lico’s forest remains one of the least disturbed on the planet. One thing’s for sure though – humans really do get everywhere.</p><img src="https://counter.theconversation.com/content/98744/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Simon Willcock received funding for this expedition from Bangor University. The expedition was part-funded by the TransGlobe Expedition Trust, Biocensus, the African Butterfly Research Institute, DMM Climbing, and Marmot tents.</span></em></p><p class="fine-print"><em><span>Phil Platts receives funding from the University of York's Environment Department. The expedition was part-funded by the TransGlobe Expedition Trust, Biocensus, the African Butterfly Research Institute, DMM Climbing, and Marmot tents.</span></em></p>Conservationists scaled the sheer cliffs of Mount Lico as part of wider effort to build the case for the protection of Mozambique’s mountain forests.Simon Willcock, Lecturer in Environmental Geography, Bangor UniversityPhil Platts, Research Fellow, University of YorkLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/988732018-06-27T13:55:45Z2018-06-27T13:55:45ZHistory teaches us that careful thought must go into planting trees<figure><img src="https://images.theconversation.com/files/224882/original/file-20180626-112623-1r83pj8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">There should be caution in jumping on the "forests are always better" bandwagon.
</span> <span class="attribution"><span class="source">Shutterstock</span></span></figcaption></figure><p>The idea that forests increase rainfall is an <a href="http://www.cambridge.org/9780521565134">old idea</a> that has inspired scientists and the public for centuries. Over 500 years ago, Christopher Columbus came to believe that the American tropics had heavy, continuous afternoon rain because of its dense vegetation. </p>
<p>In the 1860s to 1890s, the idea inspired foresters in arid places, such as South Africa and Australia, to plant trees in the hope of making rain. These efforts failed and, as a result, foresters largely abandoned the idea that trees created rainfall. In fact, it seemed that planted forests actually lowered the water available from rivers and streams; this was a major problem in areas that lacked adequate water before trees were planted. </p>
<p>A change in understanding about the impact of trees on rain and water supplies played out 80 years ago in South Africa when farmers became so concerned that planted trees were leading to the loss of water in rivers that they <a href="https://press.anu.edu.au/publications/series/world-forest-history-series/forestry-and-water-conservation-south-africa">forced the government to investigate</a> the relationship between trees and water. </p>
<p>The subsequent research showed unequivocally that tree planting had an adverse impact on water supply in South African <a href="https://www.tandfonline.com/doi/abs/10.1080/0035919X.2013.833144">catchments</a>.</p>
<p>The scientific idea that forests influence rainfall fell into decline during the middle of the twentieth century. But it has regained popularity, particularly during the past <a href="https://www.sciencedirect.com/science/article/pii/S0959378017300134">two decades</a>.</p>
<p>Evidence from various parts of the world now emphasises the link between forests and rainfall. Maps showing where the world’s rainfall <a href="https://onlinelibrary.wiley.com/doi/abs/10.1029/2010WR009127">originates</a> highlight this.</p>
<p>A group of scientists have increasingly begun to describe trees as “pumps”, “generators”, and “makers” of rain. They want <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3597246/">policies revised</a> to account for forests’ water-giving properties.</p>
<p>If successful, these ideas have the potential to revise environmental policy, ecosystems and water cycles in far reaching ways. But they also have the potential to cause significant problems if history is not heeded. </p>
<p>Research suggests we should be wary of planting trees in places where none exist, or where there are significant <a href="https://link.springer.com/article/10.1186/s40663-017-0124-9">water constraints</a>. The fact is that planting trees indiscriminately has in the past had harmful effects. </p>
<h2>Rethinking earlier theories</h2>
<p>There is strong evidence to suggest that atmospheric recycling - the transpiration of water from trees into the air as precipitation - plays an important role in rainfall in rainforests <a href="https://onlinelibrary.wiley.com/doi/abs/10.1029/2010WR009127">as well as deserts</a>. A huge percentage of rainfall – sometimes over 50% in west and central Africa and the Amazon – is recycled from forests. In parts of Western China an amazing 80-90% of rain occurs because of recycling.</p>
<p>Despite having an <a href="https://link.springer.com/article/10.1186/s40663-018-0138-y">uncertain future,</a> the connection between forests and rain is now being explored with new vigour. </p>
<p>Some scholars are calling for forests to be protected for their role in generating <a href="https://www.cifor.org/library/6408/trees-forests-and-water-cool-insights-for-a-hot-world/">rainfall and maintaining climatic stability.</a>. These scholars challenge the dominance of water policies that have been devised based on the idea that forests limit water in rivers and streams. Rather, they argue that trees are necessary to generate rain downwind. Existing policies tend to prioritise catchments, such as rivers, rather than valuing forests for their cooling and rainmaking effects. </p>
<p>This new line of thinking, which will undoubtedly reshape future policy, should not lead people to simply assume that all trees are good everywhere and all the time. The reality is that trees are very capable of being heavy water consumers that take water away from downstream users. </p>
<p>Striking a balance between the need to create rainfall and to conserve water in catchments should be a key to formulating any new policies.</p>
<p>A group of hydrological experts writing from The <a href="https://www.iucn.org/">International Union for Conservation of Nature</a>, the global authority on the status of the natural world, argue that the best approach is to protect areas where forests play a key role in generating rain locally or downwind, and to be sensitive to the potential decline of <a href="https://www.iucn.org/km/node/27186">downstream water quantities</a>. </p>
<p>Scholars who want to turn science into policy could create a detailed breakdown of world regions that may benefit from tree planting and those that are less likely to benefit. It makes sense that rainforests should be protected. What about arid regions or regions with highly variable rainfall cycles?</p>
<h2>Why history is important</h2>
<p>When devising policy, scientists should <a href="https://forestecosyst.springeropen.com/articles/10.1186/s40663-017-0124-9">read more history</a> to understand the social implications of changing policies. It is important not to repeat the same mistakes of the past, which have included planting alien trees in the middle of <a href="http://science.sciencemag.org/content/351/6269/120">diverse grasslands</a>, marginalising the voices of people who do not benefit from these efforts, and reforesting highly diverse regions with species that aren’t indigenous. </p>
<p>And people may be more biased towards pro-forestry policies, so there should be caution about not encouraging governments to just jump on the “more forests are always better” bandwagon.</p>
<p>Finally, researchers on all sides might think about getting together to design an ethical protocol for forest policy. For instance, should policies for rainfall generation be limited only to existing native forests or their previous ranges? What about the planting of alien trees, or trees in areas that were not formerly forests?</p>
<p>If the right balance is struck, the result will be resilient forests and water regimes that work.</p><img src="https://counter.theconversation.com/content/98873/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Brett M Bennett received funding from The Australian Research Council Discovery Grant for the project ‘Saving the world the first time: global climate theory and desiccation 1765-1960’( DP110104024).</span></em></p>It’s important to be wary of planting trees in places where none exist, or where there are significant water constraints.Brett M Bennett, Associate Professor of History, University of JohannesburgLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/988852018-06-26T04:34:44Z2018-06-26T04:34:44ZUrban ‘forests’ can store almost as much carbon as tropical rainforests<figure><img src="https://images.theconversation.com/files/224730/original/file-20180625-19416-1y0mho7.jpg?ixlib=rb-1.1.0&rect=71%2C363%2C4656%2C2698&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/back-view-tourists-looking-over-london-1007861020?src=nYneUb3LsTxcz8_pq3ecJQ-2-56">Shutterstock.</a></span></figcaption></figure><p>Most people would never think of London as a forest. Yet there are actually more trees in London than people. And now, new work by researchers at University College London shows that pockets of this urban jungle store as much carbon per hectare as tropical rainforests.</p>
<p><a href="http://www.un.org/en/development/desa/news/population/world-urbanization-prospects-2014.html">More than half</a> of the world’s population lives in cities, and urban trees are critical to human health and well-being. Trees provide shade, mitigate floods, absorb carbon dioxide (CO₂), filter air pollution and provide habitats for birds, mammals and other plants. The <a href="https://biodiversity.europa.eu/topics/ecosystem-services">ecosystem services</a> provided by London’s trees – that is, the benefits residents gain from the environment’s natural processes – were recently valued at <a href="http://www.treeconomics.co.uk/wp-content/uploads/LONDON-I-TREE-ECO-REPORT-151202.pdf">£130m a year</a>. </p>
<p>This may equate to less than £20 a year per tree, but the real value may be much higher, given how hard it is to quantify the wider benefits of trees and how long they live. The cost of replacing a large, mature tree is many tens of thousands of pounds, and replacing it with one or more small saplings means you won’t see the equivalent net benefit for many decades after.</p>
<h2>The trouble with measuring trees</h2>
<p>Trees absorb CO₂ during photosynthesis, which is then metabolised and turned into organic matter that makes up nearly half of their overall mass. Urban trees are particularly effective at absorbing CO₂, because they are located so close to sources such as fossil fuel-burning transport and industrial activity. </p>
<p>This carbon storage potential is an extremely important aspect of their value, but is very hard to quantify. A 120-year-old London plane tree can be 30 metres tall and weigh 40 tonnes or more, and some of the carbon in its tissues will have originated from Victorian coal fires. </p>
<p>Measuring the height of a tall tree is difficult, because it’s rarely clear exactly where the topmost point is; estimating its mass is even harder. Typically, tree mass is estimated by comparing the diameter of the trunk or the height of the tree to the mass of similar trees (ideally the same species), which have been cut down and weighed in the past. This process relies on the assumption that trees of a certain species have a clear size-to-mass ratio. </p>
<p>But a fascinating property of trees is how variable they can be, depending on their environment. So inferring the mass of urban trees from their non-urban counterparts introduces large uncertainties.</p>
<h2>Lidar over London</h2>
<p>The UCL team use a combination of cutting-edge ground-based and airborne laser scanning techniques, to measure the biomass of urban trees much more accurately. Lidar (which stands for light detection and ranging) sends out hundreds of thousands of pulses of laser light every second and measures the time taken for reflected energy to return from objects up to hundreds of metres away. </p>
<p>When mounted on a tripod on a city street, lidar builds up a millimetre accurate 3D picture of everything it “sees”, including trees. The team are using lidar methods, which they pioneered <a href="https://besjournals.onlinelibrary.wiley.com/doi/full/10.1111/2041-210X.12904">to measure</a> some of the <a href="http://rsfs.royalsocietypublishing.org/content/8/2/20170048">world’s largest trees</a>, and applying them to trees in the university’s local London Borough of Camden. </p>
<div class="sketchfab-embed-wrapper">
<iframe width="100%" height="480" src="https://sketchfab.com/models/91ec7d5793d0434184d785b2d9d15eb7/embed?autostart=1" frameborder="0" allow="autoplay; fullscreen; vr" mozallowfullscreen="true" webkitallowfullscreen="true"></iframe>
<p> <a href="https://sketchfab.com/models/91ec7d5793d0434184d785b2d9d15eb7?utm_medium=embed&utm_source=website&utm_campain=share-popup" target="_blank">Point cloud of Russell Square</a> by <a href="https://sketchfab.com/kungphil?utm_medium=embed&utm_source=website&utm_campain=share-popup" target="_blank">kungphil</a> on <a href="https://sketchfab.com?utm_medium=embed&utm_source=website&utm_campain=share-popup" target="_blank">Sketchfab</a> </p> </div>
<p>The UCL team used publicly available <a href="https://environment.data.gov.uk/ds/survey/#/survey">airborne lidar data</a> collected by the UK Environment Agency, in conjunction with their ground measurements, to estimate biomass of all the 85,000 trees across Camden. These lidar measurements help to quantify the differences between urban and non-urban trees, allowing scientists to come up with a formula predicting the difference in size-to-mass ratio, and thus measuring the mass of urban trees more accurately. </p>
<p>The findings show that Camden has a median carbon density of around 50 tonnes of carbon per hectare (t/ha), rising to 380 t/ha in spots such as Hampstead Heath and Highgate Cemetery – that’s equivalent to values seen in temperate and tropical rainforests. Camden also has a high carbon density, compared to other cities in Europe and elsewhere. For example, Barcelona and Berlin have mean carbon densities of 7.3 and 11.2 t/ha respectively; major cities <a href="https://www.sciencedirect.com/science/article/pii/S0269749113001383">in the US</a> have values of 7.7 t/ha and in China <a href="http://daneshyari.com/article/preview/1008319.pdf">the equivalent figure</a> is 21.3 t/ha.</p>
<h2>A story to tell</h2>
<p>Trees matter, to all of us. Recent protests in <a href="https://www.independent.co.uk/news/long_reads/sheffield-tree-massacre-parks-green-city-spaces-felling-street-council-yorkshire-a8286581.html">Sheffield</a>, <a href="https://www.walesonline.co.uk/news/wales-news/felling-trees-waterloo-gardens-been-14126826">Cardiff</a>, <a href="https://www.theguardian.com/environment/2018/jan/11/priest-chain-tree-protest-euston-hs2-felling-plans-london">London</a> and elsewhere, over policies of tree management and removal show how strongly people feel about the trees in their neighbourhood. Finding ways to value trees more effectively is critical to building more sustainable and liveable cities.</p>
<p>Measuring trees in new ways also helps us to see them from a new perspective. Some of these trees have incredible stories to tell. Just one example is an ash, tucked away in the grounds of St. Pancras Old Church, one of London’s (and indeed Britain’s) oldest Christian churches. </p>
<p>The tree has an extraordinary arrangement of gravestones around its roots, placed there when the railway was built from St Pancras in the mid-19th century. The job of rehousing the headstones was apparently given to a young Thomas Hardy, working as a railway clerk before going on to achieve literary fame. The UCL team’s 3D lidar data are helping monitor the state of this “Hardy Ash” tree in its dotage. This is just one of the ways new science is helping tell the stories of old trees. </p>
<div class="sketchfab-embed-wrapper">
<iframe width="100%" height="480" src="https://sketchfab.com/models/c88477e5ff5c4c4ab4d7db3970aec43d/embed?autostart=1" frameborder="0" allow="autoplay; fullscreen; vr" mozallowfullscreen="true" webkitallowfullscreen="true"></iframe>
<p> <a href="https://sketchfab.com/models/c88477e5ff5c4c4ab4d7db3970aec43d?utm_medium=embed&utm_source=website&utm_campain=share-popup" target="_blank">Hardy Tree (Camden, UK) and gravestones</a> by <a href="https://sketchfab.com/kungphil?utm_medium=embed&utm_source=website&utm_campain=share-popup" target="_blank">kungphil</a> on <a href="https://sketchfab.com?utm_medium=embed&utm_source=website&utm_campain=share-popup" target="_blank">Sketchfab</a> </p> </div><img src="https://counter.theconversation.com/content/98885/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Mathias Disney receives funding from NERC National Centre for Earth Observation (NCEO) for travel and capital funding for lidar equipment; NERC Standard Grants NE/N00373X/1 and NE/ P011780/1, CNRS Nouragues Travel Grants Program, ESA BIOMASS calibration/validation funding.</span></em></p>It’s hard to measure the value of a tree, but scientists equipped with lasers have come one step closer.Mathias Disney, Reader in Remote Sensing, UCLLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/928672018-03-16T13:27:59Z2018-03-16T13:27:59ZWe spent a year photographing the animal crop raiders of the Amazon – here are the results<figure><img src="https://images.theconversation.com/files/210546/original/file-20180315-104659-j6zj42.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Ocelot of trouble.</span> <span class="attribution"><span class="source">Mark Abrahams</span>, <span class="license">Author provided</span></span></figcaption></figure><p>Rural communities in the Amazon rainforest live alongside an incredibly diverse set of animals. When some of those animals damage and eat farmers’ crops (“crop-raiding”), it creates a challenge for conservationists, who need to understand the lives of the people who coexist with that wildlife.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/210387/original/file-20180314-113485-i0l83m.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/210387/original/file-20180314-113485-i0l83m.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=339&fit=crop&dpr=1 600w, https://images.theconversation.com/files/210387/original/file-20180314-113485-i0l83m.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=339&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/210387/original/file-20180314-113485-i0l83m.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=339&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/210387/original/file-20180314-113485-i0l83m.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=426&fit=crop&dpr=1 754w, https://images.theconversation.com/files/210387/original/file-20180314-113485-i0l83m.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=426&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/210387/original/file-20180314-113485-i0l83m.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=426&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Our home for a year.</span>
<span class="attribution"><span class="source">Mark Abrahams</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>My colleagues and I recently spent a year in the Médio Juruá region of Amazonas, Brazil, using motion-activated camera traps to take photos of the many animals that live on or near Amazonian farms. Along with interviews of farmers, this enabled us to study which animals cause the most crop damage, how this affects the livelihoods of rural Amazonians and how these communities respond to crop raiders. Our hope was to understand how this issue might affect attempts to preserve wildlife and to offer support to local farmers if they wanted it.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/210543/original/file-20180315-104694-9rxlji.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/210543/original/file-20180315-104694-9rxlji.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/210543/original/file-20180315-104694-9rxlji.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/210543/original/file-20180315-104694-9rxlji.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/210543/original/file-20180315-104694-9rxlji.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/210543/original/file-20180315-104694-9rxlji.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/210543/original/file-20180315-104694-9rxlji.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Canoeing the Amazon.</span>
<span class="attribution"><span class="source">Mark Abrahams</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>The Médio Juruá region is a vast area of staggeringly biodiverse lowland tropical forest inhabited by river-dwelling communities, who descend from a mix of indigenous Amerindians, European colonists and former slaves from Africa. Our research team (comprising myself, my colleague Professor Carlos Peres, and Hugo Costa from the State University of Santa Cruz) travelled using small boats and dug-out canoes along the sinuous waterways and through the flooded forests. The region experiences a massive ten metre-high annual flood, which has wide-ranging impacts on the local ecosystems and the livelihoods of the human inhabitants.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/210552/original/file-20180315-104635-18uuud1.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/210552/original/file-20180315-104635-18uuud1.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/210552/original/file-20180315-104635-18uuud1.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/210552/original/file-20180315-104635-18uuud1.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/210552/original/file-20180315-104635-18uuud1.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/210552/original/file-20180315-104635-18uuud1.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/210552/original/file-20180315-104635-18uuud1.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Welcoming hosts.</span>
<span class="attribution"><span class="source">Mark Abrahams</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>In the year we spent living and working with the communities of the Juruá, we were fortunate enough to participate in many aspects of life, including learning to harvest the fruit of the acai palm. Many Juruá communities are the descendants of rubber tappers (seringueiros) who were drawn to this region during the rubber boom of <a href="http://etheses.lse.ac.uk/2869/1/U615818.pdf">the late 1800s</a>. Many still depend on the natural resources of the forest and river for their livelihoods. The incredibly hospitable communities of the region frequently hosted and fed us as we travelled. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/210542/original/file-20180315-104635-otxklj.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/210542/original/file-20180315-104635-otxklj.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=359&fit=crop&dpr=1 600w, https://images.theconversation.com/files/210542/original/file-20180315-104635-otxklj.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=359&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/210542/original/file-20180315-104635-otxklj.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=359&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/210542/original/file-20180315-104635-otxklj.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=451&fit=crop&dpr=1 754w, https://images.theconversation.com/files/210542/original/file-20180315-104635-otxklj.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=451&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/210542/original/file-20180315-104635-otxklj.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=451&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Preparing manioc.</span>
<span class="attribution"><span class="source">Mark Abrahams</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>Most of the carbohydrates in rural Amazonian diets <a href="http://www.fao.org/docrep/007/y5271e/y5271e04.htm">come from manioc</a> (also known as yucca or cassava). This tough plant grows well on infertile tropical soils and has powerful chemical defences which make it pest-resistant. Farmers grow manioc using so-called “slash-and-burn” agriculture in fields called “roçados”, which are created by burning down a section of forest. They peel, grind, soak, drain and toast the manioc to remove the toxic cyanide which protects the plant from pests. The result of this process is delicious coarse flour called “farinha”, which is commonly eaten with fish soup. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/210555/original/file-20180315-104694-1rv7875.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/210555/original/file-20180315-104694-1rv7875.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=428&fit=crop&dpr=1 600w, https://images.theconversation.com/files/210555/original/file-20180315-104694-1rv7875.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=428&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/210555/original/file-20180315-104694-1rv7875.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=428&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/210555/original/file-20180315-104694-1rv7875.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=538&fit=crop&dpr=1 754w, https://images.theconversation.com/files/210555/original/file-20180315-104694-1rv7875.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=538&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/210555/original/file-20180315-104694-1rv7875.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=538&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">The large rodent crop-raiding agouti.</span>
<span class="attribution"><span class="source">Mark Abrahams</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>Despite high levels of toxins in raw manioc, some wild animals such as large rodents, deer and pig-like peccaries are able to eat it. These crop raiders can have devastating impacts on human livelihoods, destroying an average of <a href="http://onlinelibrary.wiley.com/doi/10.1002/jwmg.21443/abstract">around 8%</a> of each farmer’s crop each year. Farmers estimated that if they did not protect their crops, their losses would be roughly ten times higher. In other parts of the world, large herbivore crop raiders such as African and Asian elephants also <a href="https://books.google.co.uk/books?hl=en&lr=&id=6vNzRzcjntAC&oi=fnd&pg=PA252&dq=elephant+crop+raiding+danger+farmer&ots=j59MxRSu6h&sig=Lj2kp3m2GUVwg7dVgkSHTli6jLQ#v=onepage&q=elephant%20crop%20raiding%20danger%20farmer&f=false">endanger the lives of farmers</a>.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/210553/original/file-20180315-104694-zhrc6z.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/210553/original/file-20180315-104694-zhrc6z.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=417&fit=crop&dpr=1 600w, https://images.theconversation.com/files/210553/original/file-20180315-104694-zhrc6z.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=417&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/210553/original/file-20180315-104694-zhrc6z.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=417&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/210553/original/file-20180315-104694-zhrc6z.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=525&fit=crop&dpr=1 754w, https://images.theconversation.com/files/210553/original/file-20180315-104694-zhrc6z.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=525&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/210553/original/file-20180315-104694-zhrc6z.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=525&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Manioc farmer.</span>
<span class="attribution"><span class="source">Mark Abrahams</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>Of course, these wild and often endangered species are merely trying to survive in an increasingly human-modified landscape. Poor farmers sometimes resort to killing crop raiders to protect their lives and livelihoods and can end up resenting the conservation organisations who want to protect these species. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/210554/original/file-20180315-104694-1mvrt3e.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/210554/original/file-20180315-104694-1mvrt3e.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/210554/original/file-20180315-104694-1mvrt3e.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/210554/original/file-20180315-104694-1mvrt3e.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/210554/original/file-20180315-104694-1mvrt3e.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/210554/original/file-20180315-104694-1mvrt3e.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/210554/original/file-20180315-104694-1mvrt3e.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Setting a trap.</span>
<span class="attribution"><span class="source">Mark Abrahams</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>To study crop raiding, we set up 132 camera traps in areas next to local roçados, helped by more than 45 people living in the nearby communities.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/210513/original/file-20180315-104645-1vmpnxd.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/210513/original/file-20180315-104645-1vmpnxd.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=425&fit=crop&dpr=1 600w, https://images.theconversation.com/files/210513/original/file-20180315-104645-1vmpnxd.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=425&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/210513/original/file-20180315-104645-1vmpnxd.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=425&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/210513/original/file-20180315-104645-1vmpnxd.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=534&fit=crop&dpr=1 754w, https://images.theconversation.com/files/210513/original/file-20180315-104645-1vmpnxd.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=534&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/210513/original/file-20180315-104645-1vmpnxd.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=534&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Capuchin monkey.</span>
<span class="attribution"><span class="source">Mark Abrahams</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>We captured more than 60,000 photographs and detected over 30 species. We detected everything from fearsome predators such as pumas, to secretive nocturnal giant armadillos, to birds of prey and even primates such as capuchin monkeys. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/210581/original/file-20180315-104671-c8r3bm.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/210581/original/file-20180315-104671-c8r3bm.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=426&fit=crop&dpr=1 600w, https://images.theconversation.com/files/210581/original/file-20180315-104671-c8r3bm.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=426&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/210581/original/file-20180315-104671-c8r3bm.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=426&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/210581/original/file-20180315-104671-c8r3bm.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=536&fit=crop&dpr=1 754w, https://images.theconversation.com/files/210581/original/file-20180315-104671-c8r3bm.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=536&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/210581/original/file-20180315-104671-c8r3bm.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=536&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Giant anteater.</span>
<span class="attribution"><span class="source">Mark Abrahams</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/210576/original/file-20180315-104639-1cgtgyw.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/210576/original/file-20180315-104639-1cgtgyw.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=426&fit=crop&dpr=1 600w, https://images.theconversation.com/files/210576/original/file-20180315-104639-1cgtgyw.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=426&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/210576/original/file-20180315-104639-1cgtgyw.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=426&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/210576/original/file-20180315-104639-1cgtgyw.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=535&fit=crop&dpr=1 754w, https://images.theconversation.com/files/210576/original/file-20180315-104639-1cgtgyw.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=535&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/210576/original/file-20180315-104639-1cgtgyw.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=535&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Juvenile ornate hawk eagle.</span>
<span class="attribution"><span class="source">Mark Abrahams</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/210578/original/file-20180315-104645-6or65b.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/210578/original/file-20180315-104645-6or65b.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=426&fit=crop&dpr=1 600w, https://images.theconversation.com/files/210578/original/file-20180315-104645-6or65b.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=426&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/210578/original/file-20180315-104645-6or65b.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=426&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/210578/original/file-20180315-104645-6or65b.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=535&fit=crop&dpr=1 754w, https://images.theconversation.com/files/210578/original/file-20180315-104645-6or65b.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=535&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/210578/original/file-20180315-104645-6or65b.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=535&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Cougar.</span>
<span class="attribution"><span class="source">Mark Abrahams</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/210580/original/file-20180315-104639-1dphq6g.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/210580/original/file-20180315-104639-1dphq6g.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=425&fit=crop&dpr=1 600w, https://images.theconversation.com/files/210580/original/file-20180315-104639-1dphq6g.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=425&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/210580/original/file-20180315-104639-1dphq6g.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=425&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/210580/original/file-20180315-104639-1dphq6g.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=534&fit=crop&dpr=1 754w, https://images.theconversation.com/files/210580/original/file-20180315-104639-1dphq6g.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=534&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/210580/original/file-20180315-104639-1dphq6g.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=534&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Southern Amazon red squirrel.</span>
<span class="attribution"><span class="source">Mark Abrahams</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/210585/original/file-20180315-104642-tve4zl.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/210585/original/file-20180315-104642-tve4zl.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=426&fit=crop&dpr=1 600w, https://images.theconversation.com/files/210585/original/file-20180315-104642-tve4zl.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=426&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/210585/original/file-20180315-104642-tve4zl.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=426&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/210585/original/file-20180315-104642-tve4zl.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=536&fit=crop&dpr=1 754w, https://images.theconversation.com/files/210585/original/file-20180315-104642-tve4zl.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=536&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/210585/original/file-20180315-104642-tve4zl.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=536&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Brazilian tapir.</span>
<span class="attribution"><span class="source">Mark Abrahams</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/210511/original/file-20180315-104635-glf9eg.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/210511/original/file-20180315-104635-glf9eg.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=415&fit=crop&dpr=1 600w, https://images.theconversation.com/files/210511/original/file-20180315-104635-glf9eg.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=415&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/210511/original/file-20180315-104635-glf9eg.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=415&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/210511/original/file-20180315-104635-glf9eg.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=522&fit=crop&dpr=1 754w, https://images.theconversation.com/files/210511/original/file-20180315-104635-glf9eg.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=522&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/210511/original/file-20180315-104635-glf9eg.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=522&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Jaguar at night.</span>
<span class="attribution"><span class="source">Mark Abrahams</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>One of the most feared predators in the area is the jaguar, locally known as “onça-pintada”. We were fortunate to detect this species in several locations. Somewhat unnervingly, we occasionally saw their large fresh prints on the trail as we returned to the community, indicating that we had unwittingly been followed.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/210548/original/file-20180315-104650-z6x4v7.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/210548/original/file-20180315-104650-z6x4v7.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=314&fit=crop&dpr=1 600w, https://images.theconversation.com/files/210548/original/file-20180315-104650-z6x4v7.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=314&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/210548/original/file-20180315-104650-z6x4v7.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=314&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/210548/original/file-20180315-104650-z6x4v7.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=394&fit=crop&dpr=1 754w, https://images.theconversation.com/files/210548/original/file-20180315-104650-z6x4v7.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=394&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/210548/original/file-20180315-104650-z6x4v7.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=394&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">On the trail.</span>
<span class="attribution"><span class="source">Mark Abrahams</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>Many local residents assured us that this species is “very cunning. They see us, but we don’t see them”. We were also told a local legend that when a jaguar follows in the tracks of a human, it will sniff their tracks to decide whether or not to attack. We can only presume that we smelled so bad at that point that even our footprints were unappealing. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/210516/original/file-20180315-104673-wug8xn.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/210516/original/file-20180315-104673-wug8xn.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=425&fit=crop&dpr=1 600w, https://images.theconversation.com/files/210516/original/file-20180315-104673-wug8xn.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=425&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/210516/original/file-20180315-104673-wug8xn.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=425&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/210516/original/file-20180315-104673-wug8xn.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=534&fit=crop&dpr=1 754w, https://images.theconversation.com/files/210516/original/file-20180315-104673-wug8xn.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=534&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/210516/original/file-20180315-104673-wug8xn.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=534&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Red-billed cuckoo.</span>
<span class="attribution"><span class="source">Mark Abrahams</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>In only one location, our cameras detected a rare red-billed ground cuckoo. This was an unexpected treat. Our colleagues were among the <a href="https://www.researchgate.net/publication/261986402_Red-billed_Ground_Cuckoo_Neomorphus_pucheranii_lepidophanes">first to photograph this elusive species</a> when they worked along the Xerua river a few years ago. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/210517/original/file-20180315-104673-pttef2.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/210517/original/file-20180315-104673-pttef2.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=425&fit=crop&dpr=1 600w, https://images.theconversation.com/files/210517/original/file-20180315-104673-pttef2.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=425&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/210517/original/file-20180315-104673-pttef2.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=425&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/210517/original/file-20180315-104673-pttef2.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=534&fit=crop&dpr=1 754w, https://images.theconversation.com/files/210517/original/file-20180315-104673-pttef2.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=534&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/210517/original/file-20180315-104673-pttef2.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=534&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Razor-billed curassow.</span>
<span class="attribution"><span class="source">Mark Abrahams</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>Some species seemed to rather enjoy the limelight, while others took exception to being monitored. Razor-billed curassows frequently paraded themselves in front of the cameras, whereas a short-eared dog took it upon himself to tear a camera from the tree. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/210527/original/file-20180315-104650-1s4m377.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/210527/original/file-20180315-104650-1s4m377.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/210527/original/file-20180315-104650-1s4m377.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/210527/original/file-20180315-104650-1s4m377.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/210527/original/file-20180315-104650-1s4m377.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=565&fit=crop&dpr=1 754w, https://images.theconversation.com/files/210527/original/file-20180315-104650-1s4m377.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=565&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/210527/original/file-20180315-104650-1s4m377.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=565&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">P.</span>
<span class="attribution"><span class="source">Mark Abrahams</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>Spending long periods hiking through tropical forests surrounded by an exuberance of living things does come with certain drawbacks. For one thing, there is a bewildering array of tiny lifeforms for whom humans are mere prey. The foot sores in this image are caused by a bacterial infection known locally as “hoi hoi”.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/210531/original/file-20180315-104659-ymb3uz.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/210531/original/file-20180315-104659-ymb3uz.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=426&fit=crop&dpr=1 600w, https://images.theconversation.com/files/210531/original/file-20180315-104659-ymb3uz.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=426&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/210531/original/file-20180315-104659-ymb3uz.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=426&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/210531/original/file-20180315-104659-ymb3uz.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=535&fit=crop&dpr=1 754w, https://images.theconversation.com/files/210531/original/file-20180315-104659-ymb3uz.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=535&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/210531/original/file-20180315-104659-ymb3uz.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=535&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Collared peccary.</span>
<span class="attribution"><span class="source">Mark Abrahams</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>We also conducted 157 interviews with local people, who overwhelmingly identified five species as the most burdensome crop raiders. These were, in order of importance, the large rodent agouti, collared peccary, paca (another large rodent), red brocket deer and, to a lesser degree, the spiny rat.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/210533/original/file-20180315-104635-1ol5gnc.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/210533/original/file-20180315-104635-1ol5gnc.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=425&fit=crop&dpr=1 600w, https://images.theconversation.com/files/210533/original/file-20180315-104635-1ol5gnc.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=425&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/210533/original/file-20180315-104635-1ol5gnc.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=425&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/210533/original/file-20180315-104635-1ol5gnc.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=534&fit=crop&dpr=1 754w, https://images.theconversation.com/files/210533/original/file-20180315-104635-1ol5gnc.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=534&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/210533/original/file-20180315-104635-1ol5gnc.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=534&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Red brocket deer.</span>
<span class="attribution"><span class="source">Mark Abrahams</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>These species were some of the most frequently detected by our camera traps. They were also among the most heavily hunted species. None of these crop raiders are considered highly endangered (though the International Union for the Conservation of Nature doesn’t have enough data on <a href="http://www.iucnredlist.org/details/29619/0">red brocket deer</a> to classify them). Other studies have also found that these species can tolerate a moderate level of <a href="http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0186653">being hunted for food</a>.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/210535/original/file-20180315-104635-avk9ez.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/210535/original/file-20180315-104635-avk9ez.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/210535/original/file-20180315-104635-avk9ez.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/210535/original/file-20180315-104635-avk9ez.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/210535/original/file-20180315-104635-avk9ez.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/210535/original/file-20180315-104635-avk9ez.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/210535/original/file-20180315-104635-avk9ez.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">A hunted peccary.</span>
<span class="attribution"><span class="source">Mark Abrahams</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>We were encouraged to find that, despite the costs of crop-raiding to rural Amazonian communities, it did not seem to constitute the bitter “human-wildlife conflict” that other researchers have identified. In fact, because the most damaging crop-raiding species are fairly common, crop protection methods including hunting may not be a major threat to wildlife in this region.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/210539/original/file-20180315-104699-yd8jvz.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/210539/original/file-20180315-104699-yd8jvz.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=403&fit=crop&dpr=1 600w, https://images.theconversation.com/files/210539/original/file-20180315-104699-yd8jvz.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=403&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/210539/original/file-20180315-104699-yd8jvz.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=403&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/210539/original/file-20180315-104699-yd8jvz.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=507&fit=crop&dpr=1 754w, https://images.theconversation.com/files/210539/original/file-20180315-104699-yd8jvz.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=507&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/210539/original/file-20180315-104699-yd8jvz.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=507&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Working together.</span>
<span class="attribution"><span class="source">Hugo Costa</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>Rural tropical communities are often encouraged by people from other countries to conserve their biodiverse surroundings and are criticised for hunting that helps them survive. We hope that <a href="http://onlinelibrary.wiley.com/doi/10.1002/jwmg.21443/full">our study</a> has shed some light on the challenges faced by Amazonian communities who attempt to coexist with wildlife. They could use our results as the basis of a plan to manage the species that they hunt, just as they have implemented plans for sustainable rubber tapping and fishing in partnership with <a href="http://www.projetomediojurua.org/">international organisations</a>. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/210537/original/file-20180315-104699-t4ssck.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/210537/original/file-20180315-104699-t4ssck.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/210537/original/file-20180315-104699-t4ssck.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/210537/original/file-20180315-104699-t4ssck.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/210537/original/file-20180315-104699-t4ssck.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/210537/original/file-20180315-104699-t4ssck.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/210537/original/file-20180315-104699-t4ssck.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">The Amazon at sunset.</span>
<span class="attribution"><span class="source">Mark Abrahams</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure><img src="https://counter.theconversation.com/content/92867/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Mark Abrahams is a member of The Médio Juruá Project. He received funding from the University of East Anglia, The Explorer's Club and Idea Wild. </span></em></p>Three researchers studied the “crop raiders” of the Brazilian rainforest in the hope of aiding both local farmers and wildlife conservation.Mark Ilan Abrahams, Lecturer, University of East AngliaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/892262018-03-01T17:38:48Z2018-03-01T17:38:48ZAmazonian dirt roads are choking Brazil’s tropical streams<p>The first time I traveled to the Amazon, in 2010, I had no idea what to expect. A doctoral student from the far-off Brazilian city of Belo Horizonte, I imagined that my field work – studying fish habitats in the largest tropical forest on Earth – would be all boat rides on immense rivers and long jungle hikes.</p>
<p>In fact, all my <a href="http://www.redeamazoniasustentavel.org/">research team</a> needed was a car. That’s because the Brazilian Amazon isn’t just a rainforest: This 1.6 million square mile area is also home to villages, <a href="https://theconversation.com/for-cattle-farmers-in-the-brazilian-amazon-money-cant-buy-happiness-85349">farming</a>, logging and even <a href="https://theconversation.com/the-world-protests-as-amazon-forests-are-opened-to-mining-83034">mining</a>. That means there are <a href="http://e360.yale.edu/features/as_roads_spread_in_tropical_rain_forests_environmental_toll_grows">roads</a>, most of them dirt.</p>
<p>Scientists have long known that roads contribute to deforestation, both <a href="https://www.sciencedirect.com/science/article/pii/S000632071400264X">in the Amazon</a> and <a href="https://www.sciencedirect.com/science/article/pii/S0169534709002067">in other rainforests</a>. But <a href="https://scholar.google.co.uk/citations?user=4A_Zpj8AAAAJ&hl=en">my research</a> reveals that these transportation networks also harm Amazonian waterways, affecting the fish that thrive in this delicate habitat and endangering local communities. </p>
<h2>Water, water everywhere but not a bridge in sight</h2>
<p>Our original 2010 study examined water conditions and fish diversity in 99 small streams – called “<a href="https://www.ambiental.media/artigos/en/the-importance-of-the-amazons-small-rivers/">igarapés</a>” – in the Amazonian state of Pará. To reach them, we drove long distances past pastures, large plantations and small villages, through dense virgin forests and young regenerating jungle. </p>
<p>We also crossed a lot of rivers and streams – the waterways that nurture this rich tropical ecosystem. Rarely did we use a bridge, though. </p>
<figure class="align-left ">
<img alt="" src="https://images.theconversation.com/files/208337/original/file-20180228-36686-1a5vvzr.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/208337/original/file-20180228-36686-1a5vvzr.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=800&fit=crop&dpr=1 600w, https://images.theconversation.com/files/208337/original/file-20180228-36686-1a5vvzr.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=800&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/208337/original/file-20180228-36686-1a5vvzr.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=800&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/208337/original/file-20180228-36686-1a5vvzr.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1005&fit=crop&dpr=1 754w, https://images.theconversation.com/files/208337/original/file-20180228-36686-1a5vvzr.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1005&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/208337/original/file-20180228-36686-1a5vvzr.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1005&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Perched culverts disrupt the water flow of Amazonian streams, isolating fish.</span>
<span class="attribution"><span class="source">Rede Amazônia Sustentável</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>Instead, we discovered, most Amazonian igarapé crossings are an informal affair. Streams are narrowed with packed dirt, and water is channeled underneath via a metal pipe.</p>
<p>Most of the makeshift culverts we saw were either too narrow for the water flow or were installed too high – “perched” such that they created a sort of mini waterfall on the downstream side of the crossing, visibly disrupting the water flow. </p>
<p>A fish would really struggle to get through a perched culvert, we thought. Clearly, these informal stream crossings must be affecting local fish populations in other ways, too. I’ve spent the past eight years documenting how.</p>
<h2>Roads threaten Amazonian fish</h2>
<p>The Amazon’s rivers and streams contain a brilliantly <a href="http://onlinelibrary.wiley.com/doi/10.1111/1365-2664.13028/full">diverse array of fish</a> – so many <a href="http://wwf.panda.org/what_we_do/where_we_work/amazon/about_the_amazon/wildlife_amazon/fish/">thousands of species</a> that scientists are <a href="https://academic.oup.com/zoolinnean/article-abstract/182/1/76/4080717">still finding new fish families</a>. We counted 44 species of fish in just one small Amazonian stream. That’s <a href="https://www.ambiental.media/artigos/en/the-importance-of-the-amazons-small-rivers/">more than live in all of Denmark</a>. </p>
<p>After many hours measuring various attributes of small streams – including water depth, channel width, water flow, temperature and types of substrate – and sampling the fish that lived there, the data from <a href="https://link.springer.com/article/10.1007/s10980-016-0358-x">our 2010 study confirmed that dirt roads are ravaging Amazonian streams</a>. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/208336/original/file-20180228-36677-1po3p6l.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/208336/original/file-20180228-36677-1po3p6l.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/208336/original/file-20180228-36677-1po3p6l.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/208336/original/file-20180228-36677-1po3p6l.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/208336/original/file-20180228-36677-1po3p6l.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/208336/original/file-20180228-36677-1po3p6l.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/208336/original/file-20180228-36677-1po3p6l.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">The research team at work in an Amazonian igarapé.</span>
<span class="attribution"><span class="source">Rede Amazônia Sustentável</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>We found that makeshift road crossings cause both shore erosion and silt buildup in streams. This <a href="https://link.springer.com/article/10.1007/s10980-016-0358-x">worsens water quality</a>, hurting the <a href="http://onlinelibrary.wiley.com/doi/10.1111/ecog.02845/full">fish that thrive in this delicately balanced habitat</a>.</p>
<p>The ill-designed road crossings also act as barriers to movement, preventing fish from finding places to feed, breed and take shelter. This can lead to what’s called “<a href="http://onlinelibrary.wiley.com/doi/10.1111/ecog.02845/full">faunal homogenization</a>” because the most vulnerable aquatic species die out, leaving a less diverse fish community. </p>
<p>Disrupted water flows particularly affect carnivorous species, which tend to hunt across long distances. The dogtooth fish, or <em>Acesthrorhynchus falcatus</em>, for example, typically <a href="https://books.google.com/books?hl=en&lr=&id=iz3NBQAAQBAJ&oi=fnd&pg=PA1&dq=Acestrorhynchus+falcatus+hunting+amazon&ots=DT75TW_MaB&sig=dWmvE6e-iewmwvIAwYxQbi1DTdU#v=onepage&q&f=false">hunts in many different streams</a>, swimming from one to the other in search of prey. </p>
<p>We don’t know yet what happens to carnivorous Amazonian fish whose range is shrunk by road crossings. But malnutrition, inbreeding and even species endangerment seem like likely outcomes.</p>
<h2>Fracturing the Amazon’s watery network</h2>
<p>Amazonian streams are <a href="http://onlinelibrary.wiley.com/doi/10.1111/conl.12008/full">interconnected</a>, a natural network perfectly calibrated to transport nutrients and organic matter downstream, control water flow and regulate water quality. In short, igarapés are the essential interface between forests and the Amazon’s big rivers. </p>
<p>Informal stream crossings create blockages in this water network. I estimate that there are some 3,000 informal stream crossings in Paragominas municipality alone – and that’s just one small part of one state of the nine states that comprise the Brazilian Amazon. </p>
<p>Taken together, these makeshift “bridges” – some <a href="http://alert-conservation.org/issues-research-highlights/2014/8/1/explosion-of-illegal-roads-in-the-amazon">belonging to roads built illegally</a> – have profoundly fragmented the Amazon’s freshwater ecosystem. </p>
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<figcaption><span class="caption">Credit: Eber Evangelista; Source: <a href="http://ambiental.media/site/en/">Ambiental Media</a>, CC-BY</span></figcaption>
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<p>In the Curuá-Una River basin, for example, prior studies document <a href="https://www.sciencedirect.com/science/article/pii/S0006320716305080">one impoundment for every 4.7 miles of stream</a>. In the upper Xingu River, a southeast tributary of the Amazon River and one of the largest clearwater rivers in the Amazon basin, there are some 10,000 road crossings. There, <a href="http://rstb.royalsocietypublishing.org/content/368/1619/20120153">water temperatures have risen</a> up to 3 degrees Celsius, in part because shoreline trees are cut down to make way for crossings, allowing sunlight to penetrate. </p>
<p>Cattle ranchers across the Amazon tend to construct similar dirt crossings. Since that’s private property, though, it’s hard to know how many or measure the impacts. </p>
<h2>Building fish-friendly roads</h2>
<p>What an unnecessary problem for the fragile, embattled Amazon to have. </p>
<p>Brazilian farmers who live in the Amazon do need roads to get around and to transport their crops. But unlike logging, mining and agriculture – activities that <a href="https://www.nationalgeographic.com/environment/habitats/rainforest-threats/">profoundly threaten this fragile rainforest</a> – road-stream intersections don’t have to harm Amazonian waterways. It’s a question of design.</p>
<p>The Amazon’s transportation infrastructure is built so poorly because Brazil lacks federal guidelines for constructing rural roads in a technically correct and environmentally sensitive way. </p>
<p>Existing environmental regulations simply don’t account for the <a href="http://sustentabilidade.estadao.com.br/noticias/geral,stf-considera-constitucional-anistia-a-desmatadores-oferecida-por-novo-codigo-florestal,70002207998">negative impact of roads on waterways</a>. We even found culverts choking off streams inside the protected <a href="http://www.icmbio.gov.br/flonatapajos/">Tapajós National Forest</a>. </p>
<p>This doesn’t just hurt fish. Many Amazonian stream crossings are built during the dry season, between April and September. When the <a href="https://www.nasa.gov/feature/new-study-shows-the-amazon-makes-its-own-rainy-season">six-month-long rainy season</a> comes, the igarapés fill and swell, leading undersized culverts to rupture. Routine flash floods endanger the people who live downstream and lead to more frequent road repairs.</p>
<p>Other countries – including <a href="http://ec.europa.eu/environment/life/project/Projects/index.cfm?fuseaction=home.showFile&rep=file&fil=REMIBAR_Manual_EN.pdf">Sweden</a>, the <a href="https://www.fws.gov/asheville/htmls/project_review/bridges.html">United States</a> and <a href="http://www.dfo-mpo.gc.ca/Library/254099.pdf">Canada</a> – have all developed good technical guidelines for building and monitoring ecologically friendly road-stream crossings. Elevated bridges and <a href="http://www.tandfonline.com/doi/abs/10.1080/00028487.2015.1054519">fish-friendly culverts, for example, can minimize impacts on aquatic habitats</a>. </p>
<p>Well designed bridges would also dramatically diminish rainy-season washouts, saving money by reducing the need for such frequent rebuilding. </p>
<p>Brazil would, of course, need to adapt these technical guidelines to work in the Amazon, a tropical forest unlike anything in Europe or North America. But it’s an environment well worth the investment.</p><img src="https://counter.theconversation.com/content/89226/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Cecilia Gontijo Leal does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Thousands of dirt roads crisscross the Brazilian Amazon, serving ranchers, loggers and miners. The area’s fragile waterways — and the spectacular fish that live in them — pay a high price.Cecilia Gontijo Leal, Post-doctoral researcher in Applied Ecology, Museu Paraense Emílio Goeldi, BelémLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/912892018-02-07T00:03:20Z2018-02-07T00:03:20ZRainforest collapse in prehistoric times changed the course of evolution<p>Over <a href="https://rainforests.mongabay.com/amazon/deforestation_calculations.html">750,000 square kilometres</a> of Amazon rainforest have been cleared since 1970 – a fifth of the total. As a result, many of the animals that live there are <a href="https://www.theguardian.com/environment/2012/jul/12/amazon-deforestation-species-extinction-debt">threatened with extinction</a>. But this isn’t the first time the Earth has seen its rainforests shrink. Toward the end of the Carboniferous period, around 307m years ago, the planet’s environment shifted dramatically, and its vast tropical rainforests vanished.</p>
<p>Palaeontologists have previously struggled to work out how this rainforest collapse affected the first ancient vertebrate animals that lived there – the early tetrapods. This is because the fossil record for this time is patchy and incomplete. My colleagues and I have now <a href="http://rspb.royalsocietypublishing.org/lookup/doi/10.1098/rspb.2017.2730">published new research</a> that reveals how the collapse initially caused the number of species to fall, affecting water-loving amphibians the most. But this event ultimately paved the way for the ancestors of modern reptiles, mammals and birds – known as the amniotes – to flourish and spread across the globe.</p>
<p>About 310m years ago, long before the first dinosaurs and mammals evolved, North America and Europe lay in a single landmass at the equator covered by dense tropical rainforests, known as the “<a href="http://www.bbc.co.uk/nature/ancient_earth/Coal_forest">coal forests</a>”. The warm, humid climate and rich vegetation provided an <a href="https://theconversation.com/fossil-footprints-give-glimpse-of-how-ancient-climate-change-drove-the-rise-of-reptiles-69067">ideal habitat for amphibian-like early tetrapods</a>. This allowed them to quickly diversify into a variety of species.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/205041/original/file-20180206-14078-1e7te9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/205041/original/file-20180206-14078-1e7te9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=437&fit=crop&dpr=1 600w, https://images.theconversation.com/files/205041/original/file-20180206-14078-1e7te9.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=437&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/205041/original/file-20180206-14078-1e7te9.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=437&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/205041/original/file-20180206-14078-1e7te9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=549&fit=crop&dpr=1 754w, https://images.theconversation.com/files/205041/original/file-20180206-14078-1e7te9.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=549&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/205041/original/file-20180206-14078-1e7te9.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=549&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Carboniferous forest.</span>
<span class="attribution"><span class="source">Mark Ryan</span></span>
</figcaption>
</figure>
<p>Toward the end of the Carboniferous period, the number of tetrapod species had begun to increase greatly. But then the climate became much drier, causing a mass extinction of many species in the dominant plant groups, such as <a href="https://uwaterloo.ca/earth-sciences-museum/resources/calamite-fossils">horsetails</a> and <a href="https://www.uaex.edu/yard-garden/resource-library/plant-week/moss-giant-club-9-30-11.aspx">club mosses</a>.</p>
<p>Although the <a href="http://onlinelibrary.wiley.com/doi/10.1111/ter.12086/abstract">collapse of the rainforests</a> was a catastrophic event for plants, how it affected early tetrapods has remained largely uncertain. Previous analyses suggest that the number of <a href="http://www.bbc.co.uk/news/science-environment-11870322">early tetrapod species increased</a> through the collapse of the rainforests, but that the resulting fragmented landscape isolated different groups from each other, a pattern known as endemism.</p>
<h2>Fossil bias</h2>
<p>The problem with this research is that the early tetrapod fossil record is heavily biased. Much of what we know about early tetrapod evolution comes from extensively-studied fossil sites in midwestern and southern US, western Canada, and central Europe. This means our picture of early tetrapod evolution is biased around how much <a href="http://sp.lyellcollection.org/content/358/1/1.1">effort has been put into finding and identifying</a> fossils from these areas.</p>
<p>As with the dinosaurs, the reptile-like tetrapods of the Permian period, such as the sail-backed <a href="https://www.smithsonianmag.com/science-nature/the-dimetrodon-in-your-family-tree-54302176/"><em>Dimetrodon</em></a>, have captivated palaeontologists for many years. In contrast, the animals and landscapes of the Carboniferous period are relatively understudied. Palaeontologists and geologists are collaborating to <a href="https://www.nms.ac.uk/explore-our-collections/stories/natural-world/closing-romers-gap/">close these gaps in our knowledge</a>. Together, these biases limit our knowledge of early tetrapod diversity and can drastically affect analyses.</p>
<p>To address this problem, <a href="https://cordis.europa.eu/project/rcn/193499_en.html">my colleagues and I</a> turned to the <a href="https://paleobiodb.org/">Paleobiology Database</a>. This database is accessible to the public and is updated continuously by palaeobiologists with the location and age of all fossil finds from across the world. Instead of simply counting the species we have fossils for, we applied innovative statistical methods to the entire tetrapod fossil record.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/205049/original/file-20180206-14089-d02w8v.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/205049/original/file-20180206-14089-d02w8v.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=326&fit=crop&dpr=1 600w, https://images.theconversation.com/files/205049/original/file-20180206-14089-d02w8v.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=326&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/205049/original/file-20180206-14089-d02w8v.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=326&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/205049/original/file-20180206-14089-d02w8v.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=410&fit=crop&dpr=1 754w, https://images.theconversation.com/files/205049/original/file-20180206-14089-d02w8v.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=410&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/205049/original/file-20180206-14089-d02w8v.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=410&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<span class="caption">Carboniferous fossil tetrapods in the Paleobiology Database.</span>
<span class="attribution"><span class="source">https://paleobiodb.org/navigator/</span></span>
</figcaption>
</figure>
<p>Our results, published in the Proceedings of the Royal Society B, reveal that tetrapod species diversity decreased after the rainforest collapse, with amphibians suffering the greatest losses. The drier climate would have reduced the amount of suitable habitats for amphibian species, which are dependent on wet environments and must return to water to spawn.</p>
<p>Instead of evidence for endemism, we found that tetrapod species that survived the rainforest collapse began to disperse more freely across the globe, colonising new habitats further from the equator. Many of these survivors were early amniotes, such as diadectids and <a href="http://www.bbc.co.uk/nature/life/Synapsid">synapsids</a>, animals that had considerable advantages over amphibians. They were generally larger so could travel longer distances, and because they laid eggs they were not confined to watery habitats.</p>
<p>While the fossil record of the Carboniferous and early Permian Periods is strongly biased, new statistical methods that address these biases have allowed us to examine the true impact of the rainforest collapse on early tetrapods. We now know that the event was crucial in paving the way for amniotes, the group that ultimately gave rise to the dinosaurs and eventually modern reptiles, mammals and birds, to become the dominant group of land vertebrates.</p><img src="https://counter.theconversation.com/content/91289/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Emma Dunne receives funding from the European Research Council through its Horizon 2020 programme. </span></em></p>A drying climate caused a mass extinction among plants, but paved the way for the ancestors of modern reptiles, mammals, and birds.Emma Dunne, PhD student, University of BirminghamLicensed as Creative Commons – attribution, no derivatives.