tag:theconversation.com,2011:/uk/topics/wood-1411/articlesWood – The Conversation2023-10-06T15:15:48Ztag:theconversation.com,2011:article/2147322023-10-06T15:15:48Z2023-10-06T15:15:48ZDiscovery of half-a-million-year-old wooden structure shows we’re wrong to underestimate our ancient relatives<figure><img src="https://images.theconversation.com/files/551508/original/file-20231002-21-vds0x3.jpg?ixlib=rb-1.1.0&rect=4%2C1%2C1014%2C614&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Excavators found part of a structure formed by two overlapping logs.</span> <span class="attribution"><span class="source">Barham et al. Nature (2023)</span>, <span class="license">Author provided</span></span></figcaption></figure><p>To most people, complex technologies separate modern humans from their ancestors who lived in the Stone Age, thousands or hundreds of thousands of years ago. In today’s fast changing world, older technologies, even those from a few years ago, are often described dismissively as “Stone Age”.</p>
<p>Such terms serve to disconnect us from our ancient relatives, who were much more sophisticated than we sometimes think they were.</p>
<p>A team led by archaeologist Larry Barham at the University of Liverpool recently published robust and well dated evidence <a href="https://www.nature.com/articles/s41586-023-06557-9">for the earliest known use of wood technology</a>. The wooden structure, along with artefacts, date to 476,000 years ago and have been excavated from waterlogged deposits at <a href="https://link.springer.com/article/10.1007/BF01963510">Kalambo Falls, Zambia</a>. </p>
<p>This archaeological site is famous for producing traces of human cultural development dating to <a href="https://w%20%20%C2%A71ww.sciencedirect.com/science/article/pii/S0047248415001104">hundreds of thousands of years ago</a>. </p>
<p>The remarkably well preserved evidence found by Barham and colleagues include, among other things, a wedge (a type of wooden tool), a digging stick, a log cut with the help of tools and a branch with a notch cut into it. </p>
<p>But why, in the age of AI and robotics, should wood technology from nearly half a million years ago generate so much interest from both scientists and the public? </p>
<p>The evidence from Kalambo Falls demonstrates a remarkable ability by early hominins (ancient human relatives) to source wood and shape it with tools.
They were able to produce, not only an assortment of other tools, but also sophisticated wooden structures. We don’t know exactly what species made the structure, but <em>Homo heidelbergensis</em> or a species similar to <em>Homo naledi</em> might be candidates, among others.</p>
<p>These results have far reaching implications for our understanding of how sustainable materials were used in the Early Stone Age. It also sheds light on the capabilities of early hominins.</p>
<h2>From speculation to fact</h2>
<p>Archaeology is the study of deep and recent history using the remains of things left by people who came before us. However, these histories are biased in favour of things that have either survived the passage of time or decayed but left traces.</p>
<p>Humans lived in the era known as the Stone Age for nearly 99% of human history. <a href="https://en.wikipedia.org/wiki/African_archaeology">The Early Stone Age</a> is considered the earliest and perhaps longest “technological age”, stretching from nearly four million years ago to 300,000 years ago. </p>
<p>We know more about stone tools during this early phase of human development, in part because inorganic materials such as rocks are nearly indestructible compared to those made of perishable materials like wood. </p>
<p>Indeed, wood is very scarce in deposits belonging to the Early Stone Age, requiring <a href="https://www.sciencedirect.com/science/article/abs/pii/S0964830500000779">exceptional conditions of preservation</a> to avoid decaying. It survives only in extremely dry environments such as deserts, or extremely wet conditions – as was the case at Kalambo Falls.</p>
<p>Given the scarcity of evidence, direct proof of the intentional use of wood from more than 400,000 years ago sharply transforms our understanding of the antiquity of wood as a technology – and <a href="https://www.sciencedirect.com/science/article/abs/pii/004724849190015N?via%3Dihub">how long hominins have been interacting</a> with this versatile material. They used it to make tools, to build shelters, to obtain food and perhaps even for fuel as they went about their daily lives.</p>
<p>Although researchers had suspected that wood technology <a href="https://archaeo.peercommunityin.org/articles/rec?id=229">was widely used by early hominins</a>, without hard, direct evidence, we could not accept that as fact. Archaeology is a discovery and evidence-based field of study –- seeing is believing. The Kalambo Falls discovery transformed speculation into fact, changing our understanding of the history of technology. </p>
<h2>Benefiting the environment</h2>
<p>However, part of the challenge comes from concepts of human history which could be described as <a href="https://oxfordre.com/education/display/10.1093/acrefore/9780190264093.001.0001/acrefore-9780190264093-e-111">progressivist or linear</a> – that envisage history as an inevitable advance towards modernity through scientific and technological achievement. </p>
<p>In the past, some scientists considered the minds of early hominins to have been more limited <a href="https://www.britannica.com/science/human-evolution/Increasing-brain-size">compared to those of modern humans</a>. They believed technology and culture improved in sophistication as human brain size increased, moving from a “simple” state to the complex, algorithm-dominated world we live in today.</p>
<p>Despite the fact that brain sizes have increased over time, and that technology has changed, it is possible that those who came before us had an impressive understanding of the materials around them and cared for their surroundings. </p>
<p>The intentionally-shaped wood construction from Kalambo Falls is an illustration of design, technology and creativity – using what in today’s world we would call a green technology. </p>
<p>Notions of “progress” are quite deeply embedded in culture. This can also be a proxy for the exceptionalism of modern humans (<em>Homo sapiens</em>) – the belief that there is something unique or exemplary about our species compared with earlier hominins. If we put these notions aside, we can recognise that so called “backward technologies” can greatly benefit the environment and the planet. </p>
<p>The fact that wood is perishable makes it a more sustainable material, unlike some modern construction materials that are nearly indestructible, and leave conspicuous ruins. Manufacturing these modern materials also <a href="https://www.nature.com/articles/d41586-021-02612-5">emits greenhouse gases</a> that contribute to climate change. </p>
<p>Of course, there are risks associated with using wood as a construction material, such as fire and decay. But in appropriate situations, we should continue our long tradition of building in wood. Perhaps the ancients were not so backward, but more progressive than us when it came to looking after the planet through sound decision making.</p>
<p>In summary, the Kalambo Falls evidence suggests that, at least sometimes, early hominins were able to take advantage of materials other than stone for their everyday needs, including tool-making and shelter. They might also have been able to use the resources in their environment for fuel and medicine. </p>
<p>However, we need more direct evidence, going back to the beginnings of the Stone Age to demonstrate how those who came before us used and worked with wood. More discoveries like this might even lead us to rename the mighty Stone Age as the Wood Age.</p><img src="https://counter.theconversation.com/content/214732/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Shadreck Chirikure receives funding from the British Academy, the University of Oxford, National Research Foundation of South Africa, and the University of Cape Town. </span></em></p>Experts speculated that very early humans worked wood, but previously didn’t have the evidence.Shadreck Chirikure, Prof of Archaeological Science & British Academy Global Professor, University of OxfordLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2030902023-06-14T11:55:13Z2023-06-14T11:55:13ZClimate change is making trees bigger, but also weaker<figure><img src="https://images.theconversation.com/files/520322/original/file-20230411-755-s14pif.jpg?ixlib=rb-1.1.0&rect=2%2C0%2C1914%2C1276&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Warmer temperatures could lengthen the growing season of trees and consequently increase their growth rate.</span> <span class="attribution"><span class="source">(Shutterstock)</span></span></figcaption></figure><p>As <a href="https://public.wmo.int/en/media/press-release/eight-warmest-years-record-witness-upsurge-climate-change-impacts">global temperatures rise</a>, trees in colder areas are benefiting from an <a href="https://www.nature.com/articles/ncomms5967">extended growing season</a>. A longer growing season results in thicker growth rings and, as a result, higher overall wood production. </p>
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<img alt="" src="https://images.theconversation.com/files/524152/original/file-20230503-20-rp105s.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/524152/original/file-20230503-20-rp105s.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=600&fit=crop&dpr=1 600w, https://images.theconversation.com/files/524152/original/file-20230503-20-rp105s.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=600&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/524152/original/file-20230503-20-rp105s.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=600&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/524152/original/file-20230503-20-rp105s.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=754&fit=crop&dpr=1 754w, https://images.theconversation.com/files/524152/original/file-20230503-20-rp105s.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=754&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/524152/original/file-20230503-20-rp105s.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">
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<p><strong>This article is part of <em>La Conversation Canada’s</em> series <a href="https://theconversation.com/ca-fr/topics/foret-boreale-138017">The boreal forest: A thousand secrets, a thousand dangers</a></strong></p>
<p><br><em>La Conversation Canada invites you to take a virtual walk in the heart of the boreal forest. In this series, our experts focus on management and sustainable development issues, natural disturbances, the ecology of terrestrial wildlife and aquatic ecosystems, northern agriculture and the cultural and economic importance of the boreal forest for Indigenous peoples. We hope you have a pleasant — and informative — walk through the forest!</em></p>
<hr>
<p>However, studies suggest that longer growing seasons contribute to weakening the wood, making trees structurally weaker. The poor quality of wood means that trunks break more easily.</p>
<p>We are forest ecologists who specialize in the anatomy and growth of wood. Let’s examine the most recent scientific studies available to try to map the future of our forests and analyze how the changing growing season is determining the characteristics of the wood produced.</p>
<h2>Wood: What is it?</h2>
<p><a href="https://doi.org/10.1093/aob/mcac110">Wood</a> is the product of the progressive accumulation of cells — xylem cells — in trees. The purpose of this accumulation is to renew the sap transport system and to provide mechanical support for the stem (trunk), branches and leaves. </p>
<p>A tree ring is the product of a <a href="https://theconversation.com/climate-change-is-altering-the-seasonal-rhythm-of-plant-life-cycle-events-181231">growing season</a> which, in temperate and boreal environments, runs from spring to autumn. Each year a new growth ring is formed. The <a href="https://doi.org/10.1093/aob/mcac110">thickness of a ring</a> is dependent on a combination of factors inherent to the tree (its species and genetic factors) and environmental factors (such as soil type, sun exposure, climate and competition between neighbouring trees). </p>
<p>In some species, especially in conifers, it can be quite easy to distinguish the rings from each other. This is due to the fact that during the growing season the tree produces two types of wood, characterized by cells with different forms and functions.</p>
<p>In spring, the tree produces many large, light-coloured cells with a thin cell wall. This part of the annual ring is called “earlywood.” In late summer, growth slows down. The cells become smaller, but their walls become thicker. This “latewood” is the darker portion of the annual ring. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/514939/original/file-20230313-23-18zjsu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Large circular piece of wood cutting with tree ring texture pattern and cracks, close-up" src="https://images.theconversation.com/files/514939/original/file-20230313-23-18zjsu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/514939/original/file-20230313-23-18zjsu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/514939/original/file-20230313-23-18zjsu.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/514939/original/file-20230313-23-18zjsu.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/514939/original/file-20230313-23-18zjsu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/514939/original/file-20230313-23-18zjsu.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/514939/original/file-20230313-23-18zjsu.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>
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<span class="caption">The thickness of a tree ring depends on a combination of factors inherent to the tree (species, genetics) and environmental factors (soil type, sun exposure, climate and competition between neighbouring trees).</span>
<span class="attribution"><span class="source">(Shutterstock)</span></span>
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<p>The characteristics of the cells of wood are particularly important and are of great interest in ecological and economic terms. First of all, <a href="https://www.nature.com/articles/nplants2015160">wood cell walls stock most of the carbon assimilated from the atmosphere</a> by trees. Thus, a thicker cell wall means the tree is absorbing a greater amount of carbon. Secondly, the ratio of the number of earlywood cells to latewood cells determines the density of the wood, and, therefore, its potential use and material value.</p>
<h2>Trees are growing faster</h2>
<p>Over the past century, in the <a href="https://www.nature.com/articles/s41467-022-33196-x">temperate regions of North America</a> and <a href="https://www.nature.com/articles/ncomms5967">Europe</a>, trees have shown a faster growth rate, up to 77 per cent higher than in the previous century. This increase is related to the production of thicker growth rings.</p>
<p>At first sight, faster growth could be interpreted as higher biomass production, which would lead to a higher carbon storage capacity and, therefore, a greater contribution of our forests to the fight against climate change. In other words, a higher growth rate could mean that more wood would be available for our different needs. </p>
<p>But <a href="https://www.folger.edu/explore/shakespeares-works/alls-well-that-ends-well/read/">as William Shakespeare wrote</a>: “Oft expectation fails, and most oft there where most it promises.” </p>
<h2>Trees die younger</h2>
<p><a href="https://doi.org/10.1016/j.foreco.2018.07.045">A study by the Technical University of Munich</a> in Germany analyzed the growth rate of trees and the characteristics of their wood over the last century. They found that as the growth rate increased, the density of the wood dropped by eight to 12 per cent. </p>
<p>Furthermore, as wood density decreased, their carbon content also decreased by about 50 per cent. This suggested that the trees extracted less carbon dioxide (CO2) from the atmosphere.</p>
<p>In addition to a reduced capacity to absorb and store atmospheric carbon, reduced wood density <a href="https://doi.org/10.1016/j.foreco.2008.06.025">can weaken the structural strength of the stems</a>. Wood fulfils the important function of supporting trees. Reducing its density is therefore accompanied by a lower resistance to mechanical stresses that might come from wind or the effect of gravity on steep slopes.</p>
<p>To complicate matters further, another recent study has shown an association between <a href="https://www.nature.com/articles/s41467-020-17966-z">growth and lifespan in trees</a>: fast-growing trees have a shorter life expectancy.</p>
<h2>Too much is not enough</h2>
<p>In <a href="https://www.nature.com/articles/s41598-023-31336-x">our latest study</a>, we quantified the relationships between the length of growing season, productivity and wood cell characteristics in balsam fir.</p>
<p>The study confirmed that trees with a longer growing season produce more wood cells and a thicker growth ring. However, higher growth also corresponds to a change in the ratio between the amount of earlywood and latewood. For every day that the growing season length increased, the trees produced one more cell of earlywood.</p>
<p>The increase in the ratio between earlywood and latewood is reflected in the decrease in wood density. This shows that an increase in volume growth does not necessarily correspond to a higher biomass production.</p>
<h2>What does the future hold for our forests?</h2>
<p>The <a href="https://public.wmo.int/en/media/press-release/eight-warmest-years-record-witness-upsurge-climate-change-impacts">global average temperature has exceeded the pre-industrial average by about 1.15°C</a> (1850-1900), and is expected to rise further in the coming years. Warmer temperatures could lengthen the growing season of trees and consequently increase their growth rate.</p>
<p>While, on the one hand, this may lead to an expansion of forests globally, the rate of carbon uptake from forests is likely to decrease. </p>
<p>Although our forests will make a <a href="https://www.nature.com/articles/s41467-022-33196-x">substantial contribution to the fight against climate change</a>, the results of these studies are further evidence that environmental problems cannot be solved without taking direct action on the causes that trigger global change. </p>
<p>In the context of climate change, reducing the anthropogenic emissions that cause global warming is not something we can afford to negotiate or postpone.</p><img src="https://counter.theconversation.com/content/203090/count.gif" alt="La Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Roberto Silvestro was awarded the PBEEE grant by the Fonds de Recherche du Québec - Nature et Technologies (FRQNT).</span></em></p><p class="fine-print"><em><span>Sergio Rossi has received funding from NSERC, FRQNT and MFFP.</span></em></p>A longer growing season for trees, due to global warming, does not necessarily lead to an increase in wood production.Roberto Silvestro, PhD Candidate, Biology, Université du Québec à Chicoutimi (UQAC)Sergio Rossi, Professor, Département des Sciences Fondamentales, Université du Québec à Chicoutimi (UQAC)Licensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2013642023-05-17T14:00:59Z2023-05-17T14:00:59ZWhat log driving can teach us about forests, past and present<figure><img src="https://images.theconversation.com/files/516807/original/file-20230321-26-avunzm.jpg?ixlib=rb-1.1.0&rect=1%2C5%2C991%2C497&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">In North America, log driving is thought to have stopped by the end of the 20th century, with the exception of British Columbia, where it is still practised on a small scale.</span> <span class="attribution"><span class="source">(Shutterstock)</span></span></figcaption></figure><p>The log drive is an integral part of Québec <a href="https://www.nfb.ca/film/log_drive/">culture</a>. Specifically, log driving refers to the use of waterways to float and transport logs from harvesting sites to sawmills or ports where they are exported. </p>
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<img alt="" src="https://images.theconversation.com/files/524152/original/file-20230503-20-rp105s.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/524152/original/file-20230503-20-rp105s.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=600&fit=crop&dpr=1 600w, https://images.theconversation.com/files/524152/original/file-20230503-20-rp105s.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=600&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/524152/original/file-20230503-20-rp105s.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=600&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/524152/original/file-20230503-20-rp105s.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=754&fit=crop&dpr=1 754w, https://images.theconversation.com/files/524152/original/file-20230503-20-rp105s.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=754&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/524152/original/file-20230503-20-rp105s.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">
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<p><strong>This article is part of <em>La Conversation Canada’s</em> series <a href="https://theconversation.com/ca-fr/topics/foret-boreale-138017">The boreal forest: A thousand secrets, a thousand dangers</a></strong></p>
<p><br><em>La Conversation Canada invites you to take a virtual walk in the heart of the boreal forest. In this series, our experts focus on management and sustainable development issues, natural disturbances, the ecology of terrestrial wildlife and aquatic ecosystems, northern agriculture and the cultural and economic importance of the boreal forest for Indigenous peoples. We hope you have a pleasant — and informative — walk through the forest!</em></p>
<hr>
<p>The intensive exploitation of forests in Québec since the time of colonization has resulted in <a href="https://doi.org/10.1038/s41467-019-09265-z">major changes</a> in their structure and dynamics. Few virgin forests remain accessible today, which limits our ability to study pre-industrial forest conditions. Yet this knowledge is essential in order for us to be able to manage forests in a sustainable manner today. </p>
<p>The logs that sank to the bottom of lakes during the log driving period contain information on the history of Québec’s forests to which we have never before had access. For me, as a PhD student in paleoecology and historical ecology at the <a href="https://www.uqat.ca/recherche/grema/">Groupe de Recherche en Écologie de la MRC Abitibi (GREMA)</a> of the <a href="https://www.uqat.ca/">Université du Québec en Abitibi-Témiscamingue (UQAT)</a>, remnants of log driving represent an unprecedented opportunity to reconstruct the history of pre-industrial forest dynamics and exploitation in Québec. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/508121/original/file-20230203-20-srd12l.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="map" src="https://images.theconversation.com/files/508121/original/file-20230203-20-srd12l.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/508121/original/file-20230203-20-srd12l.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=338&fit=crop&dpr=1 600w, https://images.theconversation.com/files/508121/original/file-20230203-20-srd12l.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=338&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/508121/original/file-20230203-20-srd12l.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=338&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/508121/original/file-20230203-20-srd12l.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=424&fit=crop&dpr=1 754w, https://images.theconversation.com/files/508121/original/file-20230203-20-srd12l.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=424&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/508121/original/file-20230203-20-srd12l.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>
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<span class="caption">Timing of the use of log driving around the world.</span>
<span class="attribution"><span class="source">(Amélie Bergeron and Julie-Pascale Labrecque-Foy)</span>, <span class="license">Fourni par l'auteur</span></span>
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<h2>A practice dating back to the 10th century</h2>
<p>Over the past few centuries, logging has played a central role in the economic development of many countries, particularly for the construction of infrastructure and for trade. Forest companies used log driving because it was difficult to get access to roads and railways to transport cut logs. </p>
<p>The logs were cut, put into the water and then guided along the rivers by log drivers. Once logs arrived at the sawmills, they could be stored for several months on the surface of the lakes before being removed for their different uses. </p>
<p>Log driving is thought to have originated in the 10th century in <a href="https://doi.org/10.1016/j.jas.2018.05.002">Spain</a> and then spread across Europe over the centuries. It only appeared in <a href="https://doi.org/10.1007/s10021-005-0030-9">Scandinavia</a> and <a href="https://doi.org/10.3390/f7110257">Russia</a> in the 19th century. It began in North America around the same time, most notably in <a href="https://www.erudit.org/en/journals/hq/2001-v6-n3-hq1057791/11343ac/">Québec</a>, where it spread to all regions. Log driving in North America is believed to have stopped by the end of the 20th century, except in British Columbia, where it is still practised on a small scale.</p>
<h2>Québec forests today</h2>
<p>During the period of colonization in Québec (1800-1950), the low transportation costs of log driving made it possible for forestry companies to exploit the forests intensively. This resulted in <a href="https://doi.org/10.1016/j.foreco.2009.06.037">significant changes to forest ecosystems</a> both in their structure and dynamics.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/509537/original/file-20230210-409-7zl61t.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="River teeming with logs" src="https://images.theconversation.com/files/509537/original/file-20230210-409-7zl61t.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/509537/original/file-20230210-409-7zl61t.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=463&fit=crop&dpr=1 600w, https://images.theconversation.com/files/509537/original/file-20230210-409-7zl61t.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=463&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/509537/original/file-20230210-409-7zl61t.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=463&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/509537/original/file-20230210-409-7zl61t.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=581&fit=crop&dpr=1 754w, https://images.theconversation.com/files/509537/original/file-20230210-409-7zl61t.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=581&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/509537/original/file-20230210-409-7zl61t.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=581&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">During the log driving era, about 15 per cent of the wood transported on rivers was lost when it sunk to the bottom of lakes and rivers.</span>
<span class="attribution"><span class="source">Library and Archives Canada / PA-165128</span></span>
</figcaption>
</figure>
<p>The selective logging of the 19th century, which mainly targeted conifers, led to serious changes in the <a href="https://doi.org/10.1111/1365-2745.13474">composition of the forests</a>. The forests changed from being dominated by coniferous to deciduous trees. In terms of <a href="https://doi.org/10.1641/B580207">fire regime change</a>, since hardwoods are less flammable than conifers, there has been a major decrease in fires in Québec forests since colonization. These changes in forest composition and dynamics have resulted in decreased <a href="https://doi.org/10.1146/annurev.ecolsys.31.1.425">forest resilience</a>. In other words, the ability of forests to return to their initial state after a disturbance is now compromised.</p>
<p>In the context of climate change, this loss of resilience is worrisome, since forests are likely to be subjected to unprecedented conditions. In order to predict how forests might be modified in the future, we have to study how they responded to climate change in the past. </p>
<p>This type of study can be done through <a href="https://www.environmentalscience.org/dendrochronology-tree-rings-tell-us">dendrochronology</a>, which is the study of tree ring formation. However, in Québec, dendrochronological studies, as well as our knowledge of pre-industrial forests are limited by the young age of the trees, which are rarely older than 200 years. So we need to develop new ways to discover the hidden secrets of our forests in the past. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/508122/original/file-20230203-12399-4dxg4v.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/508122/original/file-20230203-12399-4dxg4v.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/508122/original/file-20230203-12399-4dxg4v.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=498&fit=crop&dpr=1 600w, https://images.theconversation.com/files/508122/original/file-20230203-12399-4dxg4v.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=498&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/508122/original/file-20230203-12399-4dxg4v.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=498&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/508122/original/file-20230203-12399-4dxg4v.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=626&fit=crop&dpr=1 754w, https://images.theconversation.com/files/508122/original/file-20230203-12399-4dxg4v.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=626&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/508122/original/file-20230203-12399-4dxg4v.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=626&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Anoxic conditions, lack of light and cool temperatures all favour the conservation of logs from log driving found at the bottom of lakes. Photo by Nathalie Lasselin (www.aquanat.com) at La Mauricie National Park as part of the Cinéma Submergé project (a). Once removed from the lake bottom by divers (b), the cross-sectional slices of the logs show well-defined growth rings and fire scars (identified by red arrows) that allow us to date the fires in the past (c). Photos by Julie-Pascale Labrecque-Foy (b) and Amélie Bergeron (c).</span>
</figcaption>
</figure>
<h2>Travelling back in time with the remains of log driving</h2>
<p>At the time of log driving, approximately 15 per cent of the logs transported on waterways were lost in the bottom of lakes and rivers. For example, in the Mauricie region alone, this represents more than <a href="https://savoirs.usherbrooke.ca/bitstream/handle/11143/10556/Lemay_Maud_MEnv_2017.pdf?sequence=1&isAllowed=y">13 million cubic metres of wood</a>. Anoxic conditions (absence of oxygen), the lack of light and cool temperatures (5°C) have ensured that this wood is still well preserved today. Consequently, this wood from the pre-industrial forest represents a unique opportunity to study the past of our forests.</p>
<p>Among other things, the characteristics of these logs (species, diameter, number of growth rings) tell us about the characteristics of pre-industrial forests and the cutting criteria of the time. The passage of a fire also leaves scars on surviving trees. It is possible to date these scars by dendrochronology and to reconstruct the natural fire regime in the pre-industrial era. </p>
<p>Finally, by analyzing the <a href="https://doi.org/10.5194/cp-11-1153-2015">stable isotopes</a> found in the growth rings of logs, we can reconstruct the climate of the past. This will allow us to determine how the climate influenced fires in the past, and to predict how this disturbance might be modified in the future due to climate change. Indeed, there is currently no consensus on studies that attempt to predict how the fire regime might be altered in the context of climate change. More studies on this subject are needed. </p>
<p>Our research project will provide new knowledge about pre-industrial forests and how they have responded to climate change in the past, which will help guide practices for sustainable forest management.</p><img src="https://counter.theconversation.com/content/201364/count.gif" alt="La Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Julie-Pascale Labrecque-Foy has received funding from the Natural Sciences and Engineering Research Council of Canada (NSERC) Vanier Scholarship, and the Fonds de recherche du Québec, Nature et technologies (FRQNT).</span></em></p><p class="fine-print"><em><span>Miguel Montoro Girona received funding from the Natural Sciences and Engineering Research Council of Canada (NSERC) - Discovery Grant and from Parks Canada (La Mauricie National Park) for this research.</span></em></p>Logging over the past two centuries has had a major impact on Québec’s forests. The traces it has left will guide the adoption of sustainable forest management techniques.Julie-Pascale Labrecque-Foy, Étudiante au doctorat en paléoécologie et écologie historique, Université du Québec en Abitibi-Témiscamingue (UQAT)Miguel Montoro Girona, Professeur d'écologie forestière, Université du Québec en Abitibi-Témiscamingue (UQAT)Licensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1938662022-11-10T13:45:39Z2022-11-10T13:45:39ZTogo’s new climate policies reduce greenhouse gas emissions and improve air quality – here’s how<figure><img src="https://images.theconversation.com/files/493601/original/file-20221104-15-2bzzaq.jpg?ixlib=rb-1.1.0&rect=46%2C23%2C5194%2C3374&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Using unsafe fuels for domestic cooking is a major contributor to carbon emissions in Togo. </span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/news-photo/woman-cooking-at-sokode-market-togo-news-photo/1095396160?phrase=cooking%20in%20togo&adppopup=true">gettyimages.com</a></span></figcaption></figure><p>Like many African cities, Lomé, the capital of Togo, has a pollution problem. </p>
<p>Its ambient (outdoor) air pollution levels exceed World Health Organization (WHO) <a href="https://www.who.int/news-room/feature-stories/detail/what-are-the-who-air-quality-guidelines">guidelines</a> for human health protection. Air pollution is the world’s largest environmental health risk. In Togo, a country of <a href="https://www.worldometers.info/world-population/togo-population/">8 million</a> people, it contributes to 6,700 premature <a href="https://vizhub.healthdata.org/gbd-compare/">deaths</a> per year.</p>
<p>Air pollutant emissions and emissions that contribute to climate change come largely from the same sources. They include fuel combustion in households, transport, industry, and burning of agricultural and municipal waste. Some pollutants, like black carbon and methane, contribute to both climate warming and air pollution. </p>
<p>So it makes sense to tackle the two issues together. The question is, how?</p>
<p>To do so, the government of Togo has developed a climate change plan, called its <a href="https://unfccc.int/sites/default/files/NDC/2022-06/CDN%20Revis%C3%A9es_Togo_Document%20int%C3%A9rimaire_rv_11%2010%2021.pdf">Nationally Determined Contribution</a>, which describes its climate change commitment. It has also developed a National Action Plan to Reduce Air Pollutants, which outlines actions to <a href="https://www.ccacoalition.org/en/resources/plan-national-de-r%C3%A9duction-des-polluants-atmosph%C3%A9riques-et-climatiques-de-courte-dur%C3%A9e-de">reduce air pollution</a>. </p>
<p>To inform the development of these plans, we <a href="https://www.sciencedirect.com/science/article/pii/S0048969722042048">evaluated</a> the impact that implementing ten mitigation measures in Togo would have on reducing air pollutants and climate pollutants simultaneously.</p>
<p>Togo is not the only West African country using climate change plans as public health improvement strategies. Before the 26th UN Climate Change Conference of the Parties (COP26) in Glasgow in 2021, Nigeria, Ghana, and Côte d’Ivoire submitted climate change plans. </p>
<p>If fully implemented, these plans could reduce thousands of premature deaths every year by improving air quality. </p>
<p>Showing how climate change plans can improve human health locally provides additional motivation to carry out the plans. </p>
<p>If all countries followed climate change plans like these, the global health benefit would be substantial. <a href="https://www.nature.com/articles/s41467-018-06885-9">Over one million</a> premature deaths could be avoided annually by 2050 because of air quality improvements. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/air-pollution-in-fast-growing-african-cities-presents-a-risk-of-premature-death-183944">Air pollution in fast-growing African cities presents a risk of premature death</a>
</strong>
</em>
</p>
<hr>
<h2>What we found</h2>
<p>We quantified the emissions for Togo and Grand Lomé from all major source sectors for the years between 2010 and 2018. Togo emitted an estimated 21 million tonnes of greenhouse gas emissions in 2018, predominantly from the energy, agriculture, forestry and other land use sectors. These emissions are projected to increase 42% to 30 million tonnes in 2030 if nothing is done. Without intervention air pollution is also expected to worsen, with emissions estimated to increase by between 16% and 60% across different air pollutants. </p>
<p>We found a large overlap in the major emission sources of gases and particles contributing to both climate change and degraded air quality in Togo. The overlap provides a substantial opportunity to design integrated strategies that simultaneously improve air quality and mitigate climate change.</p>
<p>Our assessment modelled how implementing ten mitigation measures in these overlapping sources would affect emissions. </p>
<p>We showed that fully implementing Togo’s two plans would reduce greenhouse gas emissions by 20% in 2030 compared to a baseline scenario, and lead to a reduction of between 25% and 78% in emissions of various health-damaging air pollutants. </p>
<p>Our paper provides a clear pathway for Togo to reduce its already small contribution to climate change while simultaneously achieving local benefits for air quality and human health. </p>
<p>The 10 mitigation measures we assessed, which are now included in Togo’s air pollution and climate change plans, included the following:</p>
<ul>
<li><p>expanding renewable electricity generation </p></li>
<li><p>increasing use of more efficient vehicles and electric vehicles</p></li>
<li><p>increasing use of cleaner fuels and more efficient stoves for cooking</p></li>
<li><p>increasing efficiency of charcoal production</p></li>
<li><p>reducing energy intensity of livestock and crop production</p></li>
<li><p>decreasing the rate of deforestation</p></li>
<li><p>capturing the use of methane from landfills and reducing open waste burning.</p></li>
</ul>
<p>Reducing the rate of deforestation was the mitigation action that would make the largest difference to Togo’s contribution to climate change. Switching to cleaner fuels for cooking in Togo would achieve the largest reduction in air pollutant emissions. </p>
<p>These measures are closely linked. Currently, wood and charcoal are the fuels most commonly used for cooking in Togo. They contribute to poor air quality and to deforestation. Therefore, switching to <a href="https://theconversation.com/renewable-energy-could-get-togo-to-its-goals-experts-identify-whats-in-the-way-186754">cleaner fuels</a>, or more efficient biomass stoves, is not only the most effective action to reduce air pollution in Togo, but also simultaneously helps achieve the largest climate change benefit through reduced deforestation. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/493604/original/file-20221104-10296-gvhly.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Man walking among trees." src="https://images.theconversation.com/files/493604/original/file-20221104-10296-gvhly.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/493604/original/file-20221104-10296-gvhly.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/493604/original/file-20221104-10296-gvhly.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/493604/original/file-20221104-10296-gvhly.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/493604/original/file-20221104-10296-gvhly.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/493604/original/file-20221104-10296-gvhly.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/493604/original/file-20221104-10296-gvhly.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">Togo must work to restore its forest cover to mitigate the impact of climate change. Photo by Matteo Fraschini Koffi/AFP via Getty Images.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/news-photo/sebastien-balouki-executive-director-of-reboisons-vite-le-news-photo/1242294605?phrase=deforestation+Togo&adppopup=true">from www.gettyimages.com</a></span>
</figcaption>
</figure>
<h2>Next steps</h2>
<p>This first assessment provides the basis for future routine updates of integrated air pollution and climate change mitigation. It can be used to monitor how Togo’s plans and strategies are being put into practice. And it can be adjusted as the situation changes.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/renewable-energy-could-get-togo-to-its-goals-experts-identify-whats-in-the-way-186754">Renewable energy could get Togo to its goals: experts identify what's in the way</a>
</strong>
</em>
</p>
<hr>
<img src="https://counter.theconversation.com/content/193866/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Chris Malley receives funding from United Nations Development Programme (UNDP) Climate Promise, the United Kingdom Engineering and Physical Sciences Research Council (EPSRC) and the Climate and Clean Air Coalition Supporting National Action & Planning initiative. </span></em></p>Togo can take bold actions to reduce climate change emissions and also improve the health of its citizens.Chris Malley, Research Fellow, The Stockholm Environment York centre, University of YorkLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1869492022-07-14T13:53:57Z2022-07-14T13:53:57ZCarbon monoxide: what is it and why is it deadly?<figure><img src="https://images.theconversation.com/files/474089/original/file-20220714-17814-zo9g6r.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Generators should not be used in confined and poorly ventilated spaces.
</span> <span class="attribution"><span class="source">Shutterstock</span></span></figcaption></figure><p>Many of us are familiar with the typical results of burning fuels such as coal, natural gas and oil. The reaction produces heat which we harness to warm our homes, heat water and cook food, power vehicles and generate electricity. </p>
<p>Combustion also produces gases, most obviously carbon dioxide. This is produced when the carbon, locked away in the petrol, gas or wood, reacts with oxygen in the air. We can’t see or smell carbon dioxide – it’s non-toxic and is unreactive – so most of the time as it drifts away into the air around us and we don’t give it a moment’s thought. </p>
<p>But carbon dioxide isn’t the only gas that results from burning of fuels. Carbon monoxide can also be produced. This too is invisible, tasteless and odourless. Unlike its chemical cousin, though, carbon monoxide is extremely poisonous. </p>
<p>The difference between the two gases is small but very significant. </p>
<p>Carbon dioxide has a central carbon atom flanked by two oxygens, hence the “di” (meaning two) in the name, and the chemical formula CO₂. It is a very stable molecule because the carbon atom has fully reacted with the oxygens, leaving it with no potential to form bonds with anything else. </p>
<p>Carbon monoxide consists of a carbon and a single oxygen (hence the “mono” in the name and the formula CO). As a result the carbon is still able to react with other molecules. This reactivity is the root of its poisonous nature.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/473888/original/file-20220713-14-d3htnf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/473888/original/file-20220713-14-d3htnf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=361&fit=crop&dpr=1 600w, https://images.theconversation.com/files/473888/original/file-20220713-14-d3htnf.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=361&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/473888/original/file-20220713-14-d3htnf.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=361&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/473888/original/file-20220713-14-d3htnf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=454&fit=crop&dpr=1 754w, https://images.theconversation.com/files/473888/original/file-20220713-14-d3htnf.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=454&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/473888/original/file-20220713-14-d3htnf.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=454&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Carbon dioxide (top) and carbon monoxide (bottom).</span>
<span class="attribution"><span class="source">Author provided</span></span>
</figcaption>
</figure>
<h2>Carbon monoxide poisoning</h2>
<p>Carbon monoxide poisoning results from the way it interacts with proteins that carry oxygen around your body. Normally haemoglobin in your blood binds oxygen as it passes through your lungs and then releases it where it is needed in the various organs of your body. Carbon monoxide also binds to haemoglobin, and it sticks over 200 times stronger than oxygen. This means it blocks the haemoglobin’s ability to bind oxygen and limits the body’s ability to move oxygen around the body. </p>
<p>The early symptoms of carbon monoxide poisoning include headaches or dizziness, breathlessness, nausea, tiredness, chest and stomach pains and visual problems. These are quite general and are easily confused with viral infections, food poisoning or just being tired. So low level poisoning is often overlooked. Higher doses result in loss of consciousness, long term heart and brain damage and death. </p>
<p>So how can we avoid being poisoned by this gas? Carbon monoxide is produced at high levels when fuels aren’t burnt correctly. This frequently occurs when wood, coal and charcoal fires are left to smoulder, or petrol, gas and kerosene appliances (such as boilers and space heaters) are not maintained properly. This is especially dangerous if generators, charcoal burners or barbecues are used in confined and poorly ventilated spaces such as tents and bars which allow CO to build up in the space with deadly consequences. </p>
<p>Early <a href="https://ewn.co.za/2022/06/30/carbon-monoxide-may-have-caused-enyobeni-tavern-deaths-paul-o-sullivan">media</a> reports suggest that carbon monoxide caused the deaths of <a href="https://www.news24.com/citypress/news/enyobeni-tavern-tragedy-what-we-know-so-far-20220627">21 young people</a> at a tavern (club) in South Africa’s Eastern Cape province in June. However, officials are still investigating and are yet to confirm the cause of these tragic deaths. </p>
<h2>Keeping safe</h2>
<p>Carbon monoxide poisoning is deadly, but it can also be easily avoided.</p>
<p><strong>Maintenance:</strong> Make sure your vehicles, boilers, chimneys, generators and space heaters are inspected and maintained by a qualified technician at least once a year. During the rest of the year, check that gas flames are blue and not yellow or orange. And look out for soot around appliances and pilot lights that go out frequently.</p>
<p><strong>Ventilation:</strong> Never use camp stoves, barbecues or charcoal heaters indoors or in tents. Only ever use petrol and diesel generators outdoors and well away from open windows and doors. Never use gas space heaters while you are sleeping, and only ever use them in well ventilated spaces. Never leave a vehicle running in a garage.</p>
<p><strong>Monitoring:</strong> Buy carbon monoxide monitors and install them near boilers, fireplaces and anywhere where you might use an indoor space heater.</p>
<p><strong>Seek treatment:</strong> If you think you or anyone near you is suffering from carbon monoxide poisoning then seek medical treatment.</p><img src="https://counter.theconversation.com/content/186949/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Mark Lorch 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>The early symptoms of carbon monoxide poisoning include headaches or dizziness, breathlessness, nausea, tiredness, chest and stomach pains and visual problems.Mark Lorch, Professor of Science Communication and Chemistry, University of HullLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1822012022-05-31T10:43:41Z2022-05-31T10:43:41ZGas prices: as cooking fuels become more expensive, people are turning to dirtier alternatives<p>One consequence of the meteoric rise in the price of fossil gas has been that cooking meals is now much more expensive. In the <a href="https://www.theguardian.com/business/2022/mar/23/food-bank-users-declining-potatoes-as-cooking-costs-too-high-says-iceland-boss">UK</a>, food bank users declined potatoes as they couldn’t afford to boil them. In <a href="https://www.thelocal.com/20220419/food-bank-use-on-the-rise-in-germany/">Germany</a>, increased heating and petrol costs have even forced some food banks to suspend their services.</p>
<p>In low and middle-income countries, over 2.5 billion people cook with <a href="https://ourworldindata.org/energy-access">liquefied petroleum gas</a> (often abbreviated to LPG). This is a byproduct of fossil gas extraction that is compressed into cylinders for distribution. The price of LPG has also increased sharply in recent months, which has led to fewer people using it for cooking. Sudden <a href="https://www.cleanairafrica.com/sites/default/files/2022-02/VAT%2520on%2520LPG%2520Policy%2520Brief_Jan%25207%25202022.pdf">price changes in LPG</a> typically see households <a href="https://iopscience.iop.org/article/10.1088/1748-9326/ac6761">revert</a> to cooking with more polluting alternatives, such as wood and charcoal, which can be gathered for free or bought in small amounts. </p>
<p>A <a href="https://african.business/2021/12/energy-resources/rising-cost-of-cooking-gas-thwarts-nigerian-climate-plans/#:%7E:text=The%2520cost%2520of%252012kg%2520of,Nigeria's%2520National%2520Bureau%2520of%2520Statistics">Nigerian news article</a> published in December 2021 described a woman who started cooking with gas two years ago but has since returned to using charcoal as LPG prices have soared. In <a href="https://economictimes.indiatimes.com/industry/energy/oil-gas/deadly-smoke-set-to-return-as-india-cuts-outlays-on-cooking-gas-program/articleshow/81404608.cms?from=mdr">India</a>, rising LPG prices coupled with the scaling back of a government programme to subsidise cooking gas are forcing people to use firewood. This has also been documented in <a href="https://rwandatoday.africa/rwanda/news/high-cost-of-cooking-gas-sends-households-back-to-firewood-3355580">Rwanda</a>, <a href="https://rioonwatch.org/?p=66346">Brazil</a>, <a href="https://e.vnexpress.net/news/trend/rising-cooking-gas-prices-bring-more-financial-pain-4435017.html">Vietnam</a> and <a href="https://www.pd.co.ke/news/kenyans-protest-sharp-rise-in-cooking-gas-prices-116906/">Kenya</a>.</p>
<p>COVID-19 lockdowns at the start of 2020 had already pushed many poorer households around the world into <a href="https://theconversation.com/covid-19-a-new-challenge-for-clean-cooking-progress-in-kenya-155900">using wood or charcoal</a> due to fuel shortages and a loss of income as businesses were closed and people were urged to stay home. Women and girls tend to <a href="https://cleancooking.org/wp-content/uploads/2021/07/CCA-gender-sheet-ENGLISH.pdf">suffer the most</a> when LPG becomes unattainable, as they are usually responsible for gathering firewood. The task can take up to <a href="https://www.sciencedirect.com/science/article/pii/S2214629619306668">several hours a week</a> and it prevents many from attending school or work.</p>
<p>Burning wood and charcoal for cooking also exposes people to dangerous levels of <a href="https://theconversation.com/air-pollution-over-three-billion-people-breathe-harmful-air-inside-their-own-homes-152986">indoor air pollution</a> in kitchens. It is estimated that this causes <a href="https://www.who.int/en/news-room/fact-sheets/detail/household-air-pollution-and-health">four million</a> premature deaths each year, out of the more than <a href="https://www.who.int/en/news-room/fact-sheets/detail/household-air-pollution-and-health">three billion people</a> exposed. Cooking with wood and charcoal is also a problem for the climate, as it emits potent greenhouse gases like <a href="https://www.ccacoalition.org/en/slcps/black-carbon">black carbon</a>.</p>
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<img alt="Three young women carry a bundle of firewood aloft." src="https://images.theconversation.com/files/466266/original/file-20220531-16-22i8wc.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/466266/original/file-20220531-16-22i8wc.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/466266/original/file-20220531-16-22i8wc.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/466266/original/file-20220531-16-22i8wc.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/466266/original/file-20220531-16-22i8wc.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/466266/original/file-20220531-16-22i8wc.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/466266/original/file-20220531-16-22i8wc.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">
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<span class="caption">The burden of gathering firewood falls disproportionately on women.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/villages-near-kalahari-desert-young-girls-11897902">Lucian Coman/Shutterstock</a></span>
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<p>But the consequences of high cooking fuel prices don’t end there.</p>
<h2>Food and energy are closely linked</h2>
<p>People in the poorest parts of the world tend to <a href="https://mecs.org.uk/wp-content/uploads/2020/12/Landscape-Study-Modern-Foods-and-Eating-Habits.pdf">consume very few processed foods</a> and lots of staple foods, such as dried beans in East Africa, which cannot be eaten raw.</p>
<p>Because they must cook most of their meals to eat, people in low-income countries typically require more energy to prepare a meal and face a difficult choice between paying for food or fuel when LPG becomes more expensive. It has been reported that a combination of rising gas and <a href="https://www.aljazeera.com/economy/2021/11/17/as-food-and-energy-prices-soar-sri-lankans-go-without">food prices</a> has forced families to eat fewer, lower-quality meals in <a href="https://www.bbc.co.uk/news/business-59952980">Sri Lanka</a> and <a href="https://e.vnexpress.net/news/trend/rising-cooking-gas-prices-bring-more-financial-pain-4435017.html">Vietnam</a>. This same pattern emerged when COVID-19 restrictions were implemented in 2020, and an inability to afford cooking fuels restricted access to adequate food in both high and low-income countries, including <a href="https://theconversation.com/kenyas-covid-19-lockdown-is-forcing-people-to-make-difficult-food-and-household-energy-decisions-158449">Kenya</a> and the <a href="https://theconversation.com/the-pandemic-has-made-it-even-harder-for-one-in-three-americans-to-obtain-healthy-affordable-food-169985">US</a>. Having to skip meals because of unaffordable fuel not only leads to malnutrition but also worsens <a href="https://theconversation.com/energy-poverty-is-linked-to-physical-and-mental-health-our-research-proves-it-176484">physical and mental wellbeing</a>.</p>
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Read more:
<a href="https://theconversation.com/cost-of-living-the-unhealthy-coping-strategies-which-are-likely-to-rise-as-energy-bills-soar-plus-how-to-get-help-183854">Cost of living: the unhealthy coping strategies which are likely to rise as energy bills soar – plus how to get help</a>
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<p>Rising cooking fuel prices can cause families to reduce their intake of protein because preparing fish and meat <a href="https://www.sciencedirect.com/science/article/pii/S0973082612000373?via=ihub">requires more energy</a> than vegetables or grains. People in low and middle-income countries are likely to avoid or undercook meals rich in protein <a href="https://www.sciencedirect.com/science/article/pii/S0973082612000373?via=ihub">to save money</a>. Protein intake already falls significantly <a href="https://www.cambridge.org/core/journals/british-journal-of-nutrition/article/dietary-protein-quality-and-malnutrition-in-africa/B77459A0CE379BADA38C184AE518ACD7">short</a> of recommended levels in many of these countries. </p>
<p>Governments can cap the price of cooking fuels and offer <a href="https://www.bbc.co.uk/news/business-60112068">targeted subsidies</a> to help those most vulnerable to energy poverty. Not only could these measures protect public health in the difficult year ahead, they could also benefit the climate.</p>
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<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">
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<p class="fine-print"><em><span>The authors 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>Cooking with wood and charcoal can raise indoor air pollution to dangerous levels.Tash Perros, PhD Candidate in Engineering, UCLMatthew Shupler, Postdoctoral Research Associate in Environmental Public Health, University of LiverpoolLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1709062021-11-15T13:13:48Z2021-11-15T13:13:48ZOrganized crime is a top driver of global deforestation – along with beef, soy, palm oil and wood products<figure><img src="https://images.theconversation.com/files/430828/original/file-20211108-25-242wwf.jpg?ixlib=rb-1.1.0&rect=0%2C6%2C2304%2C1710&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Fires burn off forest cover and natural grasses to create cattle pasture in the Maya forest in Guatemala.</span> <span class="attribution"><span class="source">Jennifer Devine</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span></figcaption></figure><p>Every year the world loses an estimated <a href="https://fra-data.fao.org/">25 million acres</a> (10 million hectares) of forest, an area <a href="https://www.in.gov/idoa/state-property-and-facilities/state-property-deeds-maps-and-photos/state-property-facts-at-a-glance/">larger than the state of Indiana</a>. Nearly all of it is in the tropics. </p>
<p>Tropical forests store enormous quantities of carbon and are home to <a href="https://doi.org/10.1073/pnas.1706264114">at least two-thirds of the world’s living species</a>, so deforestation has disastrous consequences for climate change and conservation. Trees absorb carbon dioxide as they grow, slowing its buildup in the atmosphere – but when they are burned or logged, they release their stored carbon, fueling further warming. Tropical forest loss generates nearly <a href="https://www.ipcc.ch/site/assets/uploads/2018/02/ipcc_wg3_ar5_summary-for-policymakers.pdf">50% more greenhouse gases</a> than does the global transportation sector.</p>
<p>At the 2021 U.N. conference on climate change in Glasgow, more than 100 world leaders pledged on Nov. 1 to <a href="https://www.nytimes.com/2021/11/02/climate/cop26-deforestation.html">halt deforestation by 2030</a>. In the <a href="https://ukcop26.org/glasgow-leaders-declaration-on-forests-and-land-use/">Declaration on Forests and Land Use</a>, countries outlined their strategy, which focuses on supporting trade and development policies that promote sustainable production and consumption. Governments and private companies have pledged over US$19.2 billion to support these efforts. </p>
<p>From my research on <a href="https://scholar.google.com/citations?user=BA2cjRgAAAAJ&hl=en">social and environmental issues in Latin America</a>, I know that four consumer goods are responsible for the majority of global deforestation: beef, soy, palm oil, and wood pulp and paper products. Together these commodities are responsible for the <a href="https://files.wri.org/d8/s3fs-public/estimating-role-seven-commodities-agriculture-linked-deforestation.pdf">loss of nearly 12 million acres</a> (5 million hectares) annually. There’s also a fifth, less publicized key driver: organized crime, including illegal drug trafficking. </p>
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<h2>The dominant role of beef</h2>
<p>Among major products that promote deforestation, beef is in a class by itself. Beef production is now estimated to be the biggest driver of deforestation worldwide, accounting for <a href="https://doi.org/10.1016/j.gloenvcha.2019.03.002">41% of global forest losses</a>. In the Amazon alone, cattle ranching accounts for <a href="https://www.fao.org/3/xii/0568-b1.htm">80% of deforestation</a>. From 2000 to 2011, beef production emitted <a href="https://doi.org/10.1088/1748-9326/10/12/125012">nearly 200 times more greenhouse gases</a> than soy, and 60 times more than oil palm in tropical countries with high deforestation rates.</p>
<p>Beef is produced in many countries, but it mainly drives forest losses in Latin America. On the savannas of sub-Saharan Africa and the plains of the U.S. Midwest, cattle graze without directly contributing to deforestation. </p>
<p>However, beef production in these regions indirectly contributes to deforestation by increasing demand for soy-based feed. Cattle production worldwide also drives climate change because <a href="https://doi.org/10.1038/s43016-021-00225-9">cattle emit methane</a>, a potent greenhouse gas.</p>
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<figcaption><span class="caption">Under President Jair Bolsonaro, deforestation in the Brazilian Amazon – mainly for beef and soy production – has accelerated.</span></figcaption>
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<h2>Soy and palm oil: Ubiquitous ingredients</h2>
<p>Together, soy and palm oil drive nearly <a href="https://doi.org/10.1016/j.gloenvcha.2019.03.002">10% of deforestation</a> annually – almost 2.5 million acres (1 million hectares).</p>
<p>Clearing land for palm oil plantations fuels large-scale rainforest destruction in <a href="https://theconversation.com/how-palm-oil-became-the-worlds-most-hated-most-used-fat-source-161165">Indonesia and Malaysia</a>, where most of the world’s palm oil is produced, destroying habitat for endangered and threatened species such as orangutans, elephants and tigers. More recently, palm oil production has expanded to other parts of Asia, Central and South America and Central and West Africa. </p>
<p>Palm oil is the most commonly produced, consumed and traded vegetable oil. Some <a href="https://www.fao.org/faostat/en/#data">60%</a> of the 66 million tons produced globally every year is used to produce energy in the form of biofuel, power and heat. About <a href="https://www.fao.org/faostat/en/#data">40%</a> is used for food, animal feed and chemical products. Palm oil is an ingredient in half of all products found at the supermarket, including margarine, shampoos, frozen pizza and detergents.</p>
<p>Soy production has doubled globally in the past 20 years. Nearly <a href="https://www.fao.org/faostat/en/#data/">80%</a> of global soy is fed to cows, chickens, pigs and farmed fish. This demand reflects the <a href="https://www.fao.org/faostat/en/#data/">tripling of global meat production</a> over the past 50 years. </p>
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<p>The remaining soy is largely used to produce vegetable oil and biodiesel. Humans <a href="https://doi.org/10.1111/1758-5899.12611">directly consume just 6%</a> in the form of tofu, soy milk, edamame and tempeh.</p>
<p>The United States and Brazil produce nearly 70% of the world’s annual <a href="https://www.fao.org/faostat/en/#data/">350 million-ton soy crop</a>. Brazil has rapidly caught up to U.S. production in the past 30 years, with <a href="https://theconversation.com/brazils-thriving-soy-industry-threatens-its-forests-and-global-climate-targets-56973">disastrous consequences for tropical forests in the Amazon</a>. </p>
<h2>Wood products</h2>
<p>Wood products are responsible for about <a href="https://doi.org/10.1016/j.gloenvcha.2019.03.002">5% of annual global deforestation</a>, or about 1.2 million acres (500,000 hectares) yearly. Wood is widely used for home construction and furniture, and also as a pulp source for paper and fabric. And in low-income nations and rural areas, it’s an important fuel source for heating and cooking.</p>
<p>The three <a href="https://www.statista.com/topics/1701/paper-industry/">largest paper-producing countries</a> are the U.S., Canada and China, but tropical countries have also become important pulp and paper sources. Timber plantations account for a growing share of tropical wood products, but there’s disagreement about whether this approach is <a href="https://doi.org/10.1016/j.envsci.2015.12.010">more sustainable than logging natural forests</a>. In Indonesia between 2001 and 2016, more forests were <a href="https://doi.org/10.1088/1748-9326/aaf6db">cleared to create wood product plantations</a> than for palm oil production.</p>
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<h2>Illegal deforestation and organized crime</h2>
<p>Making the supply chains for these four commodities more sustainable is an important strategy for reducing deforestation. But another industry plays an important role, especially in tropical forests: organized crime. Large, lucrative industries offer opportunities to move and launder money; as a result, in many parts of the world, deforestation is driven by the drug trade.</p>
<p>In South America and Central America, drug trafficking organizations are the vanguard of deforestation. Drug traffickers are illegally logging forests in the Amazon and <a href="https://insightcrime.org/news/intimate-relationship-between-cocaine-illegal-timber-brazil-amazon/">hiding cocaine in timber shipments to Europe</a>. In my research, I have analyzed how traffickers illegally <a href="https://doi.org/10.1016/j.gloenvcha.2020.102092">log</a> and <a href="https://doi.org/10.1111/anti.12469">raise cattle</a> in protected areas in Central America to launder money and claim drug smuggling territory. Other scholars estimate that 30% to 60% of deforestation in the region is “<a href="https://doi.org/10.1088/1748-9326/aa6fff">narco-deforestation</a>.”</p>
<p>Legal and illegal activities also interweave along the commodity chains for palm oil and soy. <a href="https://www.forest-trends.org/publications/consumer-goods-and-deforestation/">Forest Trends</a>, a U.S. nonprofit that promotes market-based approaches to forest conservation, estimates that nearly half of deforestation for commercial products like cattle, soy, palm oil and wood products is illegal. According to the group’s analysis, exports tied to illegal deforestation are worth US$61 billion annually and are responsible for <a href="https://www.forest-trends.org/wp-content/uploads/imported/for168-consumer-goods-and-deforestation-letter-14-0916-hr-no-crops_web-pdf.pdf">25% of total global tropical deforestation</a>.</p>
<p>Not all large-scale illegal deforestation is linked to drug trafficking organizations. But it is <a href="https://www.interpol.int/News-and-Events/News/2020/Forestry-crime-targeting-the-most-lucrative-of-environmental-crimes">almost always tied to organized crime</a> that depends upon corruption to operate. </p>
<p>Promoting sustainable production and consumption are critical to halting deforestation worldwide. But in my view, national and industry leaders also have to root organized crime and illicit markets out of these commodity chains. Until they do, global pledges to halt deforestation will have limited effect.</p>
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<p class="fine-print"><em><span>Jennifer Devine 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>More than 100 world leaders have pledged to end the destruction of forests by 2030 as a way to slow climate change. That will require changing how the world produces four widely used commodities.Jennifer Devine, Associate Professor of Geography and Environmental Studies, Texas State UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1656472021-09-27T12:54:47Z2021-09-27T12:54:47ZMexican communities manage their local forests, generating benefits for humans, trees and wildlife<figure><img src="https://images.theconversation.com/files/423040/original/file-20210923-13-f923j4.jpg?ixlib=rb-1.1.0&rect=23%2C3%2C2592%2C1718&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Jungle near the Palenque ruins, Chiapas, Mexico.</span> <span class="attribution"><a class="source" href="https://flic.kr/p/BxuihE">Lawrence Murray/Flickr</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span></figcaption></figure><p>The United Nations is preparing to host pivotal conferences in the coming months on two global crises: <a href="https://unfccc.int/process-and-meetings/conferences/glasgow-climate-change-conference">climate change</a> and <a href="https://www.unep.org/events/conference/un-biodiversity-conference-cop-15">biodiversity loss</a>. As experts have pointed out, these issues are fundamentally, inescapably intertwined. In both cases, human activities are <a href="https://www.un.org/sustainabledevelopment/blog/2021/06/tackling-biodiversity-climate-crises-together-and-their-combined-social-impacts/">harming nature and the support it provides to people</a>.</p>
<p>But that connection also is an opportunity. Protecting places that are both carbon- and species-rich can help slow climate change and biodiversity loss at the same time. For example, in a June 2021 report, U.N. biodiversity experts urged nations to establish strict protected areas and <a href="https://ipbes.net/sites/default/files/2021-09/ipbes_8_11_report_of_the_plenary_en.pdf">govern forests through “locally adjusted sustainable management practices</a>.” </p>
<p>I <a href="https://www.researchgate.net/profile/David-Bray-2">study Mexican community forests</a>, and believe they are the world’s best model of local sustainable management. My research over 30 years has shown that when Indigenous and local communities control their forests for commercial timber production, both humans and the land benefit.</p>
<p>As I write in my book, “<a href="https://uapress.arizona.edu/book/mexicos-community-forest-enterprises">Mexico’s Community Forest Enterprises: Success on the Commons and the Seeds of a Good Anthropocene</a>,” these forests provide hope for a better future than the one now bearing down on us. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/423041/original/file-20210923-17-4e9o4m.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Map showing Mexico's forested areas in shades of green" src="https://images.theconversation.com/files/423041/original/file-20210923-17-4e9o4m.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/423041/original/file-20210923-17-4e9o4m.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=396&fit=crop&dpr=1 600w, https://images.theconversation.com/files/423041/original/file-20210923-17-4e9o4m.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=396&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/423041/original/file-20210923-17-4e9o4m.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=396&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/423041/original/file-20210923-17-4e9o4m.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=498&fit=crop&dpr=1 754w, https://images.theconversation.com/files/423041/original/file-20210923-17-4e9o4m.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=498&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/423041/original/file-20210923-17-4e9o4m.png?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">This 2014 image, derived from ground-based and satellite images, shows the amount of organic carbon stored in the trunks, limbs and leaves of trees in Mexico. The darkest greens reveal the areas with the densest, tallest and most robust forest growth.</span>
<span class="attribution"><a class="source" href="https://eoimages.gsfc.nasa.gov/images/imagerecords/86000/86695/mexicoCarbon_gis_2014_lrg.png">NASA Earth Observatory</a></span>
</figcaption>
</figure>
<h2>Mexico’s sustainability model</h2>
<p>Mexico is <a href="https://www.nationalgeographic.com/travel/article/mexico-forests-adapts-to-a-coronavirus-year-without-tourists">one of the most biodiverse countries in the world</a>. Much of that life depends on its <a href="https://earthobservatory.nasa.gov/images/86695/counting-the-carbon-in-mexicos-forests">165 million acres (65 million hectares) of forests</a>, which cover about one-third of the nation’s land area. </p>
<p>Millions of monarch butterflies migrate from North America to forested hillsides in Mexico’s Sierra Madre mountains every winter. Tropical forests in southern Mexico harbor <a href="https://www.culturalsurvival.org/publications/cultural-survival-quarterly/time-running-out-mexicos-last-tropical-forest">jaguars, spider monkeys, crocodiles, anteaters</a> and <a href="https://www.stateofthebirds.org/2016/habitats/tropical-forests/">nearly 500 species of birds</a>.</p>
<p>As a result of the 1911-1917 Mexican Revolution, ownership of around 60% of the nation’s forests, totaling some 104 million acres (42 million hectares), was <a href="https://www.britannica.com/place/Mexico/The-Mexican-Revolution-and-its-aftermath-1910-40">transferred to local communities</a>. Over the following decades, reformers subsidized equipment and provided training in logging and business for the people who took over these important resources. Community members seized the opportunity. </p>
<p>This decades-long experiment, with government support and market incentives, has produced surprising results. Today Mexican community forest enterprises administer their common property woodlands at a scale and current maturity unparalleled anywhere else in the world. </p>
<p>Cutting down trees may seem like a counterintuitive way to slow climate change and species loss, but in Mexico it works. Community forest businesses sell profitable products like timber and bottled spring water. Some 1,600 communities sustainably log over 17 million acres of forest. They carefully select only certain trees for harvesting so that forests will vigorously regrow.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/418293/original/file-20210827-23066-anp65g.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/418293/original/file-20210827-23066-anp65g.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/418293/original/file-20210827-23066-anp65g.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=338&fit=crop&dpr=1 600w, https://images.theconversation.com/files/418293/original/file-20210827-23066-anp65g.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=338&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/418293/original/file-20210827-23066-anp65g.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=338&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/418293/original/file-20210827-23066-anp65g.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=424&fit=crop&dpr=1 754w, https://images.theconversation.com/files/418293/original/file-20210827-23066-anp65g.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=424&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/418293/original/file-20210827-23066-anp65g.jpeg?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">A worker measures logs harvested from community forests in Durango.</span>
<span class="attribution"><span class="source">David Bray, CC-BY-ND</span></span>
</figcaption>
</figure>
<h2>Measuring results</h2>
<p>Research shows that Mexico’s model supports conservation. One study of 733 municipalities in eight states found that deforestation rates were lower in managed forests with <a href="http://dx.doi.org/10.1177/1070496512447249">high percentages of commonly owned land</a>. Community forests in the tropical state of Quintana Roo have lower deforestation rates than public protected areas in southern Mexico, using logging practices that <a href="https://repository.si.edu/bitstream/handle/10088/19403/serc_Lynch_and_Whigham_1995.pdf">preserve habitat for wintering migratory birds</a>. </p>
<p>In the Sierra Norte of Oaxaca, 23 communities with a total area of over 500,000 acres have zoned their territory so that 78% of it is forested for <a href="https://doi.org/10.1016/j.landusepol.2018.06.056">sustainable production and conservation</a>, leaving the remainder for agriculture and other uses.</p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/423043/original/file-20210923-23-1b81bsa.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Orange and black bird on a branch." src="https://images.theconversation.com/files/423043/original/file-20210923-23-1b81bsa.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/423043/original/file-20210923-23-1b81bsa.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=480&fit=crop&dpr=1 600w, https://images.theconversation.com/files/423043/original/file-20210923-23-1b81bsa.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=480&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/423043/original/file-20210923-23-1b81bsa.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=480&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/423043/original/file-20210923-23-1b81bsa.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=603&fit=crop&dpr=1 754w, https://images.theconversation.com/files/423043/original/file-20210923-23-1b81bsa.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=603&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/423043/original/file-20210923-23-1b81bsa.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=603&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Altamira oriole (<em>Icterus gularis</em>), Tinum, Yucatan.</span>
<span class="attribution"><a class="source" href="https://flic.kr/p/21eiY7h">Becky Matsubara/Flickr</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<p>The Sierra Norte community of Pueblos Mancomunados manages its 78,000 acres mostly as a community park focused on ecotourism. Foresters cut trees only to control bark beetle outbreaks. Zapotec Indigenous people have lived here for over 1,000 years, and residents have practiced sustainable logging for decades. </p>
<p>This region has some of the <a href="https://doi.org/10.1016/j.worlddev.2004.10.005">highest biodiversity in Mexico</a>. New species are <a href="http://dx.doi.org/10.11646/zootaxa.4329.1.2">commonly discovered here</a>, such as <a href="https://doi.org/10.11646/zootaxa.4329.1.2"><em>Charadrahyla esperancensis</em></a>, a tree frog with a protruding snout.</p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/423160/original/file-20210924-46667-nckkw7.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Brown frog on mossy rock." src="https://images.theconversation.com/files/423160/original/file-20210924-46667-nckkw7.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/423160/original/file-20210924-46667-nckkw7.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=459&fit=crop&dpr=1 600w, https://images.theconversation.com/files/423160/original/file-20210924-46667-nckkw7.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=459&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/423160/original/file-20210924-46667-nckkw7.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=459&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/423160/original/file-20210924-46667-nckkw7.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=577&fit=crop&dpr=1 754w, https://images.theconversation.com/files/423160/original/file-20210924-46667-nckkw7.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=577&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/423160/original/file-20210924-46667-nckkw7.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=577&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption"><em>Charadrahyla esperancensis</em>, a tree frog discovered in a cloud forest in Oaxaca in 2017.</span>
<span class="attribution"><a class="source" href="https://doi.org/10.11646/zootaxa.4329.1.2">Canseco-Márquez, et al., 2017</a>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<h2>Community forests reduce poverty</h2>
<p>Over a 20-year period, from 1993 to 2013, the thickly forested landscape of Sierra Norte has also produced 3 million metric tons of timber and carbon, mostly stored in furniture and construction materials. By storing carbon in long-lasting products, sustainably managed forests actually <a href="https://www.springer.com/gp/book/9789400722316">capture more carbon than strictly conserved forests</a> </p>
<p>These operations also benefit local economies. In a 2019 study, Mexican researcher <a href="https://ceiba.org.mx/quienes-somos/miembros/name/juan-manuel-torres-rojo/">Juan Manuel Torres-Rojo</a> and colleagues found that in a sample of over 5,000 Mexican forest communities, government support for forestry, particularly for investments in social and human capital, <a href="https://doi.org/10.1016/j.worlddev.2019.04.016">significantly reduced poverty</a>. </p>
<p>The most serious challenges confronting community forests are the impacts of organized crime. Gangs charge communities in several states protection money and reportedly have physically <a href="https://www.reuters.com/article/us-mexico-trafficking-lumber-trfn/mexican-crime-gangs-branching-into-illegal-logging-researchers-warn-idUSKCN2242LB">taken over community forest businesses</a> in some northern states. </p>
<p>Illegal logging is also a serious problem, but it is concentrated in communities that <a href="https://uapress.arizona.edu/book/mexicos-community-forest-enterprises">are not managing their forests</a>. Mexican community forests are less vulnerable to stresses like the deforestation, fire and drought that <a href="https://doi.org/10.1098/rstb.2007.0036">threaten large swaths of the Amazon basin</a> because neighboring communities depend on their forests for their livelihoods and constantly monitor them. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/419181/original/file-20210902-13-1d1fqhy.jpeg?ixlib=rb-1.1.0&rect=111%2C79%2C4723%2C2624&q=45&auto=format&w=1000&fit=clip"><img alt="Foresters outdoors in hard hats and safety vests." src="https://images.theconversation.com/files/419181/original/file-20210902-13-1d1fqhy.jpeg?ixlib=rb-1.1.0&rect=111%2C79%2C4723%2C2624&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/419181/original/file-20210902-13-1d1fqhy.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=338&fit=crop&dpr=1 600w, https://images.theconversation.com/files/419181/original/file-20210902-13-1d1fqhy.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=338&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/419181/original/file-20210902-13-1d1fqhy.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=338&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/419181/original/file-20210902-13-1d1fqhy.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=424&fit=crop&dpr=1 754w, https://images.theconversation.com/files/419181/original/file-20210902-13-1d1fqhy.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=424&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/419181/original/file-20210902-13-1d1fqhy.jpeg?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">Community forest workers in Vencedores, Durango, Mexico with author David Bray (third from right).</span>
<span class="attribution"><span class="source">David Bray</span>, <a class="license" href="http://creativecommons.org/licenses/by-nc-nd/4.0/">CC BY-NC-ND</a></span>
</figcaption>
</figure>
<h2>Giving communities control helps land</h2>
<p>Governments of developing countries often have little money to manage protected land. Giving communities control over valuable forests and the resources to manage them is an affordable alternative.</p>
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<p>Mexico’s community forests sustain themselves and generate profits. They do not depend on government subsidies, although they have received them over the years, as a pro-community forest public policy initiative. In my view, mobilizing community collective action around timber – a product that, unlike most small farmer crops, virtually always has a good price – is a market-oriented way to stop deforestation and conserve biodiversity.</p>
<p>However, many governments don’t have the political will to give this kind of ownership, management authority, training and equipment to local communities. I believe that if the results achieved in Mexico were more widely known, they could help convince other governments that promoting community forestry can deliver political stability, poverty reduction and a more livable climate.</p><img src="https://counter.theconversation.com/content/165647/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>David Bray has received funding from the former North-South Center of the University of Miami, the Fulbright-Hays Program for Mexico, the William and Flora Hewlett Foundation, the Ford Foundation, the Tinker Foundation, and the US Agency for International Development. </span></em></p>About 60% of Mexico’s forests are managed by local communities. A scholar who has studied the forests for 30 years explains how this system protects the forests and the people who oversee them.David Bray, Professor of Earth and Environment, Florida International UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1674262021-09-08T10:34:52Z2021-09-08T10:34:52ZCut less, leave longer: decades of data show we are over-exploiting tropical rainforests<figure><img src="https://images.theconversation.com/files/419754/original/file-20210907-19-1r98vgm.JPG?ixlib=rb-1.1.0&rect=0%2C0%2C4275%2C2837&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">We are logging more than can be sustained by tropical forests. </span> <span class="attribution"><span class="source">Plinio Sist</span>, <span class="license">Fourni par l'auteur</span></span></figcaption></figure><p>Tropical rainforests currently cover 1070 million hectares of the world’s surface. More than 90% of them are located in three regions: Central Africa, in the Congo Basin; South America, mostly in the Amazon; and in Southeast Asia, in Indonesia, Malaysia and Papua New Guinea.</p>
<p>It is estimated that 400 million hectares of these forests are currently given over to timber production. But our research over many decades shows the <a href="https://conbio.onlinelibrary.wiley.com/doi/full/10.1111/j.1755-263X.2012.00242.x">rules that govern</a> timber harvesting in tropical forest – currently based on logging intensity and cutting cycle – do not allow for the long-term recovery of the timber volume being harvested from these ecosystems.</p>
<p>These observations question the very foundations of the so-called “sustainable management” of these forests, and indicates that we will see further degradation of the planet’s last timber-producing tropical rainforests. It is therefore urgent that we seek out new sources of timber. Natural forests alone will not be able to meet current and future demand.</p>
<p>The principles of tropical silviculture – the management of forests to meet the needs of diverse groups and industries – must also be completely revised.</p>
<h2>No time to recover</h2>
<p>Timber harvesting in tropical forests concerns only a very small number of trees of commercial interest: one to three trees per hectare in Africa, five to seven in the Amazon, and eight in Southeast Asia. Just a few species, including ipe, cumaru, okoumé and sapelli are exploited worldwide.</p>
<p>Among these, only the largest trees of more more than 50 to 80 cm in diameter are felled and harvested. The forest is then left to rest, generally for 25 to 35 years, depending on a specific country’s legislation. These rest periods, known as “rotations”, should theoretically allow the forest to recover the stock of harvested timber.</p>
<p>But our <a href="https://www.museo-editions.com/product-page/vivre-avec-les-for%C3%AAts-tropicales">data</a> shows that, in reality, these resting periods are vastly underestimated.</p>
<figure class="align-center ">
<img alt="Hill forests in Borneo (Indonesia)" src="https://images.theconversation.com/files/412097/original/file-20210720-25-1n0l5mh.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/412097/original/file-20210720-25-1n0l5mh.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/412097/original/file-20210720-25-1n0l5mh.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/412097/original/file-20210720-25-1n0l5mh.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/412097/original/file-20210720-25-1n0l5mh.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/412097/original/file-20210720-25-1n0l5mh.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/412097/original/file-20210720-25-1n0l5mh.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">Hill forests in Borneo (Indonesia).</span>
<span class="attribution"><span class="source">Plinio Sist</span></span>
</figcaption>
</figure>
<p>Since the early 1980s, CIRAD and its partners have set up <a href="https://tmfo.org/">experimental plots</a> to monitor tropical forest dynamics in order to assess the effects of selective logging on the reconstitution of the timber stock. This information now allows us to simulate the trajectories of exploited tropical rainforests according to the harvesting intensity, but also other variables – including rainfall and soil type.</p>
<p>Using this information, we calculated the reconstitution of a forests’s biomass, the commercial volume of timber and the evolution of biodiversity within the Amazon basin to highlight <a href="https://iopscience.iop.org/article/10.1088/1748-9326/ab195e">significant differences</a> within the same region.</p>
<p>We found that, in general, the rotation times of 25-35 years in force in most tropical countries are insufficient to fully reconstitute the timber volume removed. On the other hand, biodiversity and biomass seem to recover <a href="https://conbio.onlinelibrary.wiley.com/doi/full/10.1111/j.1755-263X.2012.00242.x">fairly quickly within 20-25 years</a>, after which more than 80% of biodiversity remains at the level of the pre-harvest level.</p>
<h2>Unsustainable production</h2>
<p>In the Brazilian Amazon, current forest protection legislation is based on a 35-year cycle, with an harvesting intensity of 15-20 m<sup>3</sup> per hectare and an initial proportion of commercial species of 20%. At this rate, and considering a harvesting area of 35 million hectares, the level of production cannot be maintained beyond one harvesting cycle of 35 years, and will then decline each year until the resources are depleted.</p>
<p>Only by reducing harvesting intensity by half and a 65-year cutting cycle would ensure sustainable and constant timber production; however, in this situation, only <a href="https://www.cirad.fr/espace-presse/communiques-de-presse/2021/durabilite-des-concessions-forestieres-bresiliennes">31% of current demand</a> could be met.</p>
<p>In Southeast Asia, the cutting cycle period is 20 to 30 years, and logging intensities in primary forest, on average 80m<sup>3</sup> per hectare, can exceed 100m<sup>3</sup> per hectare. But data from forest dynamics monitoring indicate that only an <a href="https://www.cifor.org/knowledge/publication/1409">intensity of 60m³ per hectare every 40 years</a> would ensure sustainable and consistent production over time.</p>
<p>Finally, in Central Africa, the recovery of the stock of timber removed 25 years after logging is only 40%, suggesting a recovery <a href="https://royalsocietypublishing.org/doi/10.1098/rstb.2012.0302">of barely 50% over a 30-year rotation</a>.</p>
<h2>A new system for harvesting timber</h2>
<p>The idea behind tropical silviculture, designed more than half a century ago, is that natural tropical forests are capable of producing timber in a sustained manner. In light of our results, this position must be completely revised.</p>
<p>The monitoring of tropical forests dynamics after logging shows that, in most tropical countries, they will not be able to meet the growing market demand for timber within 30 years, according to the rules established by forestry legislation.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/419841/original/file-20210907-5388-1lmj0c5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A tropical forest near Congo Brazzaville" src="https://images.theconversation.com/files/419841/original/file-20210907-5388-1lmj0c5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/419841/original/file-20210907-5388-1lmj0c5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=398&fit=crop&dpr=1 600w, https://images.theconversation.com/files/419841/original/file-20210907-5388-1lmj0c5.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=398&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/419841/original/file-20210907-5388-1lmj0c5.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=398&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/419841/original/file-20210907-5388-1lmj0c5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=501&fit=crop&dpr=1 754w, https://images.theconversation.com/files/419841/original/file-20210907-5388-1lmj0c5.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=501&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/419841/original/file-20210907-5388-1lmj0c5.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"></a>
<figcaption>
<span class="caption">Central African tropical forests barely recover by 50% before being logged again.</span>
<span class="attribution"><a class="source" href="https://www.flickr.com/photos/bobulix/6379255773/in/photolist-aHHmuv-aHHkkP-aHHjQF-aHHmXp-aHHkUp">Bobulix</a>, <a class="license" href="http://creativecommons.org/licenses/by-nc-nd/4.0/">CC BY-NC-ND</a></span>
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<p>In the vast majority of cases, true sustainability would require a considerable reduction in the harvesting intensity and a significant increase in the duration of logging cycles, which compromises the economic sustainability of selective logging in the current legislation system.</p>
<p>Natural tropical forests can no longer be perceived as a simple source of timber: the environmental services they produce should also be taken into account. For example, we could consider pricing timber from natural forests higher than that from plantations, with intended use linked to the higher quality of their wood. This higher price would increase the economic profitability of timber harvesting in natural forests, while plantation wood could be used for less noble purposes.</p>
<p>There is an urgent need to promote diversified tropical forestry now, combining timber production from natural forests, mixed plantations, agroforests (human-created forest systems with a multi-level vegetation structure similar to natural forests), and secondary forests (those regenerated on deforested areas left to be abandoned).</p>
<p>The rising international interest in tropical forest restoration under the <a href="https://www.bonnchallenge.org/">Bonn Challenge</a> – a plan to restore 350 million hectares of deforested land by 2030 – or the very recent proclamation of the <a href="https://www.un.org/press/fr/2019/ag12124.doc.htm">UN Decade of Ecosystem Restoration</a> (2021-2030), are both opportunities to implement this new approach in the tropics.</p>
<p>But no new system aimed at sustainable timber production will be successful without also introducing effective policies to combat illegal logging and deforestation, which continue to supply the timber market at lower costs and compete with any logging system aimed at long-term sustainability.</p><img src="https://counter.theconversation.com/content/167426/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Plinio Sist is the coordinator of the TmFO (Tropical managed Forests Observatory) network, which focuses on the resilience of exploited tropical forests with the aim of formulating recommendations for sustainable forestry. TmFO is governed by a memorandum of understanding signed by 18 forestry research institutions. TmFO currently has 32 experimental sites spread over 12 countries on three continents (Amazonia, Congo Basin and Southeast Asia), with a total of 639 forest plots representing a total inventoried area of 1258 hectares. This network is funded by CIRAD, the CGIAR Forests Trees and Agroforestry program and the French Ministry of Europe and Foreign Affairs in support of the Alliance for the Preservation of Tropical Rainforests.</span></em></p>Observations collected since the 1980s in the Amazon, Central Africa and Southeast Asia show we are not giving tropical forests enough time to recover after logging.Plinio Sist, Écologue des forêts tropicales, CiradLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1566252021-04-26T12:12:57Z2021-04-26T12:12:57ZHow do people make paper out of trees, and why not use something else?<figure><img src="https://images.theconversation.com/files/393671/original/file-20210406-23-kttw6p.jpg?ixlib=rb-1.1.0&rect=17%2C3%2C2354%2C1575&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Future notebook paper?</span> <span class="attribution"><a class="source" href="https://flic.kr/p/AhhoZx">Not4rthur/Flickr</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span></figcaption></figure><figure class="align-left ">
<img alt="" src="https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=293&fit=crop&dpr=1 600w, https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=293&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=293&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=368&fit=crop&dpr=1 754w, https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=368&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=368&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<p><em><a href="https://theconversation.com/us/topics/curious-kids-us-74795">Curious Kids</a> is a series for children of all ages. If you have a question you’d like an expert to answer, send it to <a href="mailto:curiouskidsus@theconversation.com">CuriousKidsUS@theconversation.com</a>.</em></p>
<hr>
<blockquote>
<p><strong>How do people make paper out of trees, and why not use something else? – Cooper H., age 6, St. Louis, Missouri</strong></p>
</blockquote>
<hr>
<p>Paper is an important part of modern life. People use it in school, at work, to make artwork and books, to wrap presents and much more. Trees are the most common ingredient for paper these days, but people have been taking notes and creating artworks for a very long time using lots of other kinds of surfaces and materials.</p>
<p>Humans <a href="https://www.bbc.com/news/world-asia-50754303">painted pictures on cave walls during the Ice Age</a>. The oldest known drawing, found on a small rock in South Africa, was made <a href="https://www.bbc.com/news/science-environment-45501205">73,000 years ago</a>. </p>
<p>Written language came a long time later. The <a href="https://www.ancient.eu/Sumerian_Language/">Sumerians</a>, in what is now Iraq, and the Egyptians used pictures in the <a href="https://www.bl.uk/history-of-writing/articles/where-did-writing-begin">first written languages</a> more than <a href="https://www.livescience.com/53406-early-egyptian-queen-revealed-in-hieroglyphs.html">5,000 years ago</a>. </p>
<p>These people etched cuneiform and hieroglyph pictures that formed their languages into rock. They also wrote on slabs of wet clay, using a pen or brush made from a reed. Sometimes they baked these slabs hard in ovens to preserve them. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/393408/original/file-20210405-17-rkvvwp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/393408/original/file-20210405-17-rkvvwp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/393408/original/file-20210405-17-rkvvwp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=399&fit=crop&dpr=1 600w, https://images.theconversation.com/files/393408/original/file-20210405-17-rkvvwp.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=399&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/393408/original/file-20210405-17-rkvvwp.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=399&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/393408/original/file-20210405-17-rkvvwp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=501&fit=crop&dpr=1 754w, https://images.theconversation.com/files/393408/original/file-20210405-17-rkvvwp.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=501&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/393408/original/file-20210405-17-rkvvwp.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"></a>
<figcaption>
<span class="caption">Ancient Egyptian manuscript written and drawn on papyrus, dating to 1275 B.C.</span>
<span class="attribution"><a class="source" href="https://www.webcitation.org/63YCN7sEt">British Museum</a></span>
</figcaption>
</figure>
<p>The Egyptians pioneered the first paper. <a href="https://www.metmuseum.org/toah/hd/pyma/hd_pyma.htm">Papyrus</a> came from a 15-foot-tall (4.5 meter) plant of the same name that grew in marshlands along the Nile River. They cut the stalk into thin strips, pressed them together and dried them into the long rolls you can now see preserved in museums. They wrote in ink, which didn’t smudge or blur on this new paper. Papyrus made it easy to carry their writing with them in rolled up scrolls – much easier than carting around heavy clay tablets and rocks.</p>
<p>Wood tablets covered in beeswax became a popular writing material in Greece, Rome and Egypt. Children used them in school as you might use notebooks today. Heating the wax made it easy to erase the writing and reuse the tablets. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/393420/original/file-20210405-19-1du07zq.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/393420/original/file-20210405-19-1du07zq.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/393420/original/file-20210405-19-1du07zq.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=412&fit=crop&dpr=1 600w, https://images.theconversation.com/files/393420/original/file-20210405-19-1du07zq.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=412&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/393420/original/file-20210405-19-1du07zq.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=412&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/393420/original/file-20210405-19-1du07zq.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=518&fit=crop&dpr=1 754w, https://images.theconversation.com/files/393420/original/file-20210405-19-1du07zq.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=518&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/393420/original/file-20210405-19-1du07zq.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=518&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Wax writing tablets from a Greek school ‘notebook’ used around 2,000 years ago.</span>
<span class="attribution"><a class="source" href="https://www.bl.uk/collection-items/greek-wax-tablets">British Library</a></span>
</figcaption>
</figure>
<p>The Romans took the next step, making books with papyrus pages. Special manuscripts used pages made of treated calf skin. </p>
<p>In China, ancient writing materials included <a href="https://www.bl.uk/history-of-writing/articles/the-evolution-of-writing">bone, bronze and wood</a>. But then, a little more than 2,000 years ago, the Chinese <a href="https://www.dkfindout.com/us/history/ancient-china/chinese-paper-making/">invented a different kind of paper</a>. Early on, it was <a href="https://paper.gatech.edu/invention-paper-0">made from the hemp plant</a>, washed and soaked in water until it was soft. Then it was beaten into a gooey pulp with a wooden mallet and smoothed into a flat frame to dry. </p>
<p>It took Europeans another 800 years to finally start making paper. They cut up, soaked and treated linen and cotton rags. A half a century later, in 1690, the first rag-paper mill came to the American Colonies. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/393673/original/file-20210406-23-dsvfmc.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/393673/original/file-20210406-23-dsvfmc.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/393673/original/file-20210406-23-dsvfmc.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/393673/original/file-20210406-23-dsvfmc.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/393673/original/file-20210406-23-dsvfmc.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/393673/original/file-20210406-23-dsvfmc.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/393673/original/file-20210406-23-dsvfmc.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/393673/original/file-20210406-23-dsvfmc.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">This human-made forest is planted with gum tree saplings that will eventually be harvested.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/forest-trees-farm-blue-sky-royalty-free-image/462224143">ChrisVanLennepPhoto/iStock via Getty Images</a></span>
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</figure>
<p>But as people used more and more paper, rags grew scarce. There were more trees than rags, so trees became the raw material. The first U.S. newspaper that was printed on paper made from ground-up wood was the Jan. 14, 1863, edition of the Boston Weekly Journal.</p>
<p>So how do people make paper out of trees today? Loggers cut trees, load them onto trucks and bring them to mills. Machines slice off the bark, and big wood chippers chop the logs into small bits. Those chips are boiled into a soup that looks like toothpaste. To get out any lumps, it is smashed flat, dried and cut up into sheets of paper. </p>
<p>The entire process, from planting a seedling to buying your school notebook, takes a very long time. Just growing the trees takes 10 to 20 years.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/7IP0Ch1Va44?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">This animation shows how trees are made into paper.</span></figcaption>
</figure>
<p>Making tons of paper from trees can <a href="https://www.worldatlas.com/articles/how-many-trees-does-it-take-to-make-1-ton-of-paper.html">harm the planet</a>. Humans cut down <a href="http://www.fao.org/forest-resources-assessment/en/">80,000 to 160,000 trees</a> around the world every day, and use many of them to make paper. Some of those trees come from tree farms. But loggers also cut down forests for paper, which means that animals and birds lose their homes. </p>
<p>Cutting forests down also <a href="https://www.cbc.ca/news/technology/logging-climate-1.5588979">contributes to climate change</a>, and paper factories <a href="https://us.macmillan.com/books/9781250155931">pollute the air</a>. After you throw paper in the trash, a truck takes it to a dump, where it takes six to nine years to decompose.</p>
<p>That’s why <a href="https://www.epa.gov/facts-and-figures-about-materials-waste-and-recycling/paper-and-paperboard-material-specific-data#">recycling is important</a>. It saves a lot of trees, slows climate change and helps protect endangered animals, birds and all creatures that rely on forests for their homes and food.</p>
<p>Did you know that it takes 24 trees to make one ton of paper, which is about 200,000 sheets? You may use a piece of paper one or two times, but it can be <a href="https://archive.epa.gov/wastes/conserve/materials/paper/web/html/faqs.html#times">recycled five to seven times</a>. Recycling one ton of paper saves 17 trees. If it’s recycled seven times, it saves 117 trees.</p>
<p>So if paper isn’t good for the environment, why don’t people write on something else? The answer: They do. With computers, tablets and cellphones, people use much less paper than in the past. Maybe a day will come when we won’t use paper at all – or will save it for very special books and artworks. </p>
<hr>
<p><em>Hello, curious kids! Do you have a question you’d like an expert to answer? Ask an adult to send your question to <a href="mailto:curiouskidsus@theconversation.com">CuriousKidsUS@theconversation.com</a>. Please tell us your name, age and the city where you live.</em></p>
<p><em>And since curiosity has no age limit – adults, let us know what you’re wondering, too. We won’t be able to answer every question, but we will do our best.</em></p><img src="https://counter.theconversation.com/content/156625/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Beverly Law 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>People have painted on cave walls and written on clay and wax tablets, papyrus and paper made from wood. Could screens replace paper someday?Beverly Law, Professor Emeritus of Global Change Biology and Terrestrial Systems Science, Oregon State UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1559002021-03-24T14:45:37Z2021-03-24T14:45:37ZCOVID-19: a new challenge for clean cooking progress in Kenya<figure><img src="https://images.theconversation.com/files/388472/original/file-20210309-13-j8hscv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Cooking on solid fuels exposes people to toxic pollutants.</span> <span class="attribution"><span class="source">JEKESAI NJIKIZANA/AFP via Getty Images</span></span></figcaption></figure><p><a href="https://www.iea.org/reports/africa-energy-outlook-2019">Over 90%</a> of the <a href="https://unstats.un.org/sdgs/report/2019/goal-11/">238 million people</a> living in sub-Saharan Africa’s informal settlements, rely upon solid fuels for cooking, heating, and lighting their homes. These fuels include wood, charcoal, dung and straw. They’re typically gathered or traded locally and burned on open fires, generating toxic pollutants. </p>
<p>The most harmful of these pollutants is known as fine Particulate Matter or PM2.5. When inhaled, these particles are so tiny that they can penetrate deep into the lungs, causing damage to the blood vessels and increasing the risk of heart and lung diseases. Indoor levels of pollution generated in biomass fuel homes – which are typically poorly ventilated – <a href="https://www.tandfonline.com/doi/full/10.1080/00207233.2020.1732067">frequently exceed World Health Organisation (WHO) guidelines</a> and are hazardous to human health. </p>
<p>Typically, as the income of a household rises, <a href="https://journals.assaf.org.za/index.php/jesa/article/view/3310">occupants transition</a> towards cleaner domestic energy alternatives – such as liquid petroleum gas or electricity. In the process of moving along the “energy ladder” households may use “transition” fuels, such as charcoal or kerosene. These are more efficient than raw biomass fuels, thereby reducing meal preparation times. </p>
<p>However, supplies of liquid petroleum gas and electricity in sub-Saharan Africa are often <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3154221/">vulnerable to commodity shocks</a> caused by economic, social, or political instability. </p>
<p>For instance, the <a href="https://theconversation.com/africa/covid-19">COVID-19 pandemic</a> disrupted global energy markets and supply chains due to early collapse in global oil demand. This resulted in <a href="https://onlinelibrary.wiley.com/doi/10.1111/oet.12773">volatile petroleum prices</a> and the price fluctuation presents <a href="https://www.iea.org/reports/africa-energy-outlook-2019">major challenges to those in resource poor settings</a>. </p>
<p>We have studied how these changes affect low-income households in Kenya. We are part of a <a href="https://www.asap.uk.com/daq-east-africa">joint collaborative effort</a> – by the <a href="https://www.birmingham.ac.uk/index.aspx">University of Birmingham</a> and the <a href="https://www.popcouncil.org/">Population Council</a>, a research organisation dedicated to critical health and development issues – exploring how social, behavioural, economic and environmental factors affect household air pollution exposure. </p>
<p>In 2020 the <a href="https://dataverse.harvard.edu/dataset.xhtml?persistentId=doi:10.7910/DVN/VO7SUO">Population Council launched</a> a large research project with the aim of documenting the experiences of people living in low-income settlements during the COVID-19 pandemic. Part of this included data collection on fuel use and whether people were switching cooking fuels. </p>
<p>Using these data, we found that during the pandemic, access to cleaner household fuels has become variable and disrupted.</p>
<p>In recent years there has been a significant increase in the use of liquid petroleum gas in Kenya. While nationally levels are lower, with only 5.6% of rural areas using liquid petroleum gas, in urban areas <a href="https://s3-eu-west-1.amazonaws.com/s3.sourceafrica.net/documents/119795/VOLUME-IV-KPHC-2019.pdf">52.9% of households use it</a>. Kenya has set a <a href="http://documents1.worldbank.org/curated/en/955741536097520493/pdf/129734-BRI-PUBLIC-VC-LW89-OKR.pdf">national target of 35% clean energy by 2030</a> but may fall short of this goal. </p>
<p>Our findings suggest that the COVID-19 pandemic risks reversing progress made to increase access to affordable, reliable and sustainable domestic energy sources in Kenya. Risks are greatest among those that live in informal settlements. This further increases health inequities as the poorest households have the highest risk of household air pollution exposure. </p>
<p>This could also signal a wider trend happening in other sub-Saharan African countries. </p>
<h2>Surveying informal settlements</h2>
<p>The project surveyed 1,750 households across five Nairobi informal settlements; Kibera, Mathare, Dandora, Kariobangi, and Huruma. Household air pollution is a <a href="https://www.who.int/news-room/fact-sheets/detail/household-air-pollution-and-health">major health concern</a> in these settings. </p>
<p>In mid 2019, prior to COVID-19, our survey respondents were using kerosene (58%), charcoal/biomass/wood (24%) or liquid petroleum gas/ electricity (18%). In 2020, the proportion using liquid petroleum gas or electricity increased to 29%. This highlights an improvement overall, driven by advances in availability and affordability of cleaner fuels. However, additional survey questions in the 2020 suggests a more complex picture. </p>
<p>In the survey, residents were asked how their cooking practices and household behaviours had changed. Most households (56%) reported that fuel was more expensive or more difficult to obtain since the pandemic. Of those who said fuel was now more expensive, almost half (46%) were using liquid petroleum gas or electricity. This suggests that access to clean fuels was difficult due to price changes or household income loss. </p>
<p>About 19% said fuel was actually cheaper to get now. Of these, 97% were using kerosene – potentially reflecting the <a href="https://www.bls.gov/opub/mlr/2020/article/from-the-barrel-to-the-pump.htm#:%7E:text=The%20production%20boom%20coincided%20with,to%20the%20COVID%2D19%20pandemic.&text=Producer%20prices%20for%20crude%20petroleum%20declined%2034.0%20percent,and%2048.8%20percent%20in%20April">rapid drop in global petroleum prices</a> – and about 25% said the price was the same as usual (66% kerosene users). This suggests that COVID-19 may be increasing availability and decreasing the cost of kerosene, while increasing the cost of liquid petroleum gas.</p>
<p>Of particular concern is our finding that 69% of liquid petroleum gas or electricity users before the COVID-19 pandemic reported a subsequent switch to kerosene. This reflects the fragility of fuel transitions: shocks often influence, at least over the short-term, household choices. This is worrying as prior to COVID-19 <a href="https://static1.squarespace.com/static/5a6b5aad12abd97ed4679071/t/5e56a8f3672e8272382f76ff/1582737656154/ASAP+-+East+Africa+-+Vulnerability+Scoping+Study+-+Low+Income+Households+in+Kampala.pdf">a study found kerosene using households had PM2.5 levels almost equal to those in charcoal or wood-using households</a>. </p>
<p>Looking at the data, we believe that people were making the switch because of economic hardship. Overall 43% of survey respondents had lost their jobs or sources of livelihood. And 71% reported their household expenses had increased despite these economic losses. Also kerosene prices were decreasing at the time. </p>
<p>Participants also reported they had changed cooking behaviours, with a third (34%) spending more time preparing meals. Twice as many were women (40%) compared to men (24%). These patterns may be due to disproportionate loss of employment experienced by women, who were more likely to take up additional domestic duties or caring responsibilities. </p>
<p>Switching back to more polluting cooking fuels (mainly kerosene) – combined with spending more time undertaking indoor domestic duties – will increase overall exposure to hazardous levels of household air pollution among those living in Nairobi’s already vulnerable informal settlements.</p>
<p>This combination of social, behavioural, economic and environmental factors has major implications for household air pollution exposure. And it’s an existing area of research for the <a href="https://www.asap.uk.com/daq-east-africa">Digital Air Quality – East Africa</a> research programme, of which we are co-investigators. </p>
<h2>Supporting clean cooking</h2>
<p>It’s widely recognised that national governments should support a permanent switch to liquid petroleum gas or electricity cooking, to <a href="https://www.who.int/airpollution/household/chest/en/">reduce exposure to household air pollution</a>. The Kenyan government has been promoting greater use of liquid petroleum gas primarily by <a href="https://www.lse.ac.uk/GranthamInstitute/wp-content/uploads/2018/10/8737_vol3.pdf">fiscal measures</a>. These includ a zero tax rating for liquid petroleum gas, a value added tax (VAT) exemption for clean and efficient cookstoves and disincentivising the use of kerosene as a cooking fuel by raising excise duty and therefore retail prices. </p>
<p>However, the COVID-19 pandemic has exposed the vulnerability of such programmes to volatile energy markets. It’s evident that access to clean energy supplies alone is inadequate. Additional measures are needed to fully implement clean cooking practices. </p>
<p>There needs to be more focus on how disruptive shocks influence household fuel use and the need for cost-effective interventions that discourage short-term use of heavily polluting fuels.</p><img src="https://counter.theconversation.com/content/155900/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Suzanne Bartington receives funding from the Natural Environment Research Council, National Institute for Health Research and Engineering and Physical Sciences Research Council. She is an elected member of Oxfordshire County Council. </span></em></p><p class="fine-print"><em><span>Jessie Pinchoff receives funding from the ASAP-East Africa project as one of the researchers on the consortium.</span></em></p><p class="fine-print"><em><span>William Robert Avis receives funding from the UK Government's Foreign, Commonwealth and Development Office and a number of research councils (including the Engineering and Physical Sciences Research Council (EPSRC) and Medical Research Council (MRC).</span></em></p>The COVID-19 pandemic risks reversing progress made to increase access to affordable, reliable and sustainable domestic energy sources in Kenya.Suzanne Bartington, Clinical Research Fellow in Environmental Health, University of BirminghamJessie Pinchoff, Associate researcher, Population CouncilWilliam Robert Avis, Research Fellow, University of BirminghamLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1534622021-02-23T14:56:04Z2021-02-23T14:56:04ZWhy efforts to clean up charcoal production in sub-Saharan Africa aren’t working<figure><img src="https://images.theconversation.com/files/385503/original/file-20210222-13-17a4syk.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Charcoal is an essential fuel for most parts of sub-Saharan Africa</span> <span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/File:Charcoal_before_pick-up.jpg">AnandievanZyl/Wikimedia Commons</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span></figcaption></figure><p>Charcoal is an essential source of domestic fuel in many sub-Saharan African countries. Overall, the region produces 65% of the world’s charcoal, with Nigeria, Ethiopia and Ghana being the <a href="https://www.tandfonline.com/doi/full/10.1080/19376812.2020.1846133">top three producers</a>. The charcoal sector employs about 40 million people in the region. Smallholders are responsible for most charcoal production, and it’s an important safety net for most producers.</p>
<p>The average person in sub-Saharan Africa consumes 0.69 cubic metres of charcoal per year. That’s 2.5 times more than the amount of wood fuel an average person consumes globally. </p>
<p>Producing charcoal involves burning wood under anaerobic conditions – when too much oxygen is supplied, the wood turns to ash. Typically, the production technique – earth kilns, used by smallholders – cannot properly regulate the oxygen supply, leading to inefficiencies. Simply put, they use more wood to produce little charcoal and emit more emissions compared to emerging carbonisation techniques. </p>
<p>As a result charcoal production is one of the main drivers of savannah and forest degradation in sub-Saharan Africa.</p>
<p>Nevertheless, demand for charcoal is rising. This has led to governments attempting to formalise the sector. One such step has involved enabling investments from large-scale companies. For example, in Ghana, the government leases out forest reserves to private companies to produce wood on plantations for conversion to charcoal. Another step involves introducing punitive policies. For example, in Malawi, the state forbids smallholders from producing charcoal without permits, with noncompliance leading to fines and up to ten years imprisonment. </p>
<p>I conducted <a href="https://www.tandfonline.com/doi/full/10.1080/19376812.2020.1846133">a review</a> of charcoal production and recent developments in sub-Saharan Africa.</p>
<p>It’s not clear that formalisation tackles challenges at the grassroots. For the charcoal sector to transition towards sustainability, I argue for the adoption of integrated approaches that pay attention to the social needs of actors while tackling environmental concerns. This should preferably be done under the banner of ‘carbon-neutral charcoal’.</p>
<h2>Efforts to formalise the sector</h2>
<p>In recent years, many countries, including Ghana and Malawi, have tried to formalise the charcoal sector.</p>
<p>Their reasons for doing so have varied, and have included the desire to:</p>
<ul>
<li><p>increase revenue from charcoal to state governments through taxes, and </p></li>
<li><p>reduce the perceived environmental impacts of charcoal production. </p></li>
</ul>
<p>The consequences of these endeavours are contested.</p>
<p>For example, in Ghana, in a bid to promote sustainable charcoal production, the government enabled foreign investors to acquire large tracts of fertile land for wood production.</p>
<p>The effect was that many smallholders have been displaced from their lands and means of production. </p>
<p>The idea behind introducing taxes is also unclear. For example, in Ghana the government <a href="https://www.modernghana.com/news/831002/the-woes-of-the-forest-of-northern-ghana-a-nation.html">imposed taxes</a> on smallholder charcoal producers with no clear plan on how these taxes would lead to sanitising the charcoal sector or support the countryside’s development. </p>
<p>Malawi has imposed outright bans on charcoal production without permits. This has removed a crucial safety net for smallholders, forcing them into poverty. </p>
<p>In addition to the fact that many interventions have failed to work, it’s also become clear that smallholders employ several strategies to subvert sanctions instituted by the state government. These include using illegal means to transport charcoal and paying bribes to law enforcement agencies. <a href="http://www.kenyaforestservice.org/documents/redd/Charcoal%20Value%20Chain%20Analysis.pdf">Kenya</a> is one country where this happens.</p>
<p>There is also ample evidence that prohibitions such as banning the production and transport of charcoal don’t work in many countries in the region because of weak institutions. </p>
<p>Given that the current path towards formalisation is failing, what alternatives can governments adopt?</p>
<h2>Cleaning the charcoal sector</h2>
<p>Making the charcoal sector less carbon intensive is desirable. But the current pathways chosen by various governments aren’t sustainable because they deprive many poor farmers of the means of their survival. </p>
<p>I identify a number of steps that could be taken.</p>
<p>First, national governments need to recognise and improve traditional leaders’ current role in allocating trees for charcoal production in the countryside. This approach has been in place for decades in countries, including Ghana.</p>
<p>It has its flaws. For example, there is no proper accountability for how traditional leaders apply revenues raised from allocating wood resources. But it has nevertheless helped sustain the population of valuable tree species in the savannah, including the shea tree (<em>Vitellaria paradoxa</em>) and the African locust bean tree (<em>Parkia biglobosa</em>) in Ghana. </p>
<p>Second, governments need to invest in the countryside, creating awareness and facilitating green charcoal businesses and associations. This way smallholders could produce charcoal from sustainable woodlots that are harvested in rotation. </p>
<p>Efforts also need to be made to address some of the structural challenges along the charcoal commodity chain, including the skewed distribution of profits to traders and merchants. The creation of cooperatives could help by strengthening the bargaining position of smallholder charcoal producers. </p>
<p>Finally, improving charcoal production at the grassroots level will allow governments in the region to tap into the growing global demand for sustainable charcoal in international markets, while contributing to climate change mitigation.</p><img src="https://counter.theconversation.com/content/153462/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Eric Kumeh Mensah 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>Attempts to formalise charcoal production have been largely unsuccessful.Eric Kumeh Mensah, Doctoral Researcher, University of HohenheimLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1549812021-02-10T11:05:35Z2021-02-10T11:05:35ZTransparent wood is coming, and it could make an energy-efficient alternative to glass<figure><img src="https://images.theconversation.com/files/383275/original/file-20210209-21-13uxgyc.jpg?ixlib=rb-1.1.0&rect=73%2C30%2C3854%2C3214&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Glass windows like these could be replaced with wood.</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/view-through-window-cottage-into-snowcovered-1567864882">Shutterstock/Visions-AD</a></span></figcaption></figure><p>Wood is an ancient material humans have been using for millions of years, for the construction of housing, ships and as a source of fuel for burning. It’s also a renewable source, and one way to capture excess carbon dioxide from the Earth’s atmosphere. Today, the main component of wood - cellulose – is produced annually at <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5746563/">20 times the volume of steel.</a></p>
<p>One thing you wouldn’t use wood for is making windows. Instead we rely on glass and plastic, which are transparent and, when toughened, can give structural support. But buildings lose a lot of heat through glass, and while light can bring some heat through the material, it’s not a good insulator. This is why we need double glazing. Wood, on the other hand, is highly insulating but it’s not transparent. Usually.</p>
<p>In recent years, materials scientists have been experimenting with making wood transparent. Making wood see-through, and retaining its high mechanical properties, would provide a good alternative to glass from a sustainable and renewable source. <a href="https://onlinelibrary.wiley.com/doi/full/10.1002/adom.201800059">Previous methods</a> of doing this were highly energy intensive and used harmful chemicals, but <a href="https://advances.sciencemag.org/content/7/5/eabd7342">a new study</a> has shown a way to make wood transparent without using huge amounts of energy in the process.</p>
<h2>Seeing through wood</h2>
<p>Wood’s lack of transparency comes from the combination of its two main components, cellulose and lignin. The lignin absorbs light, and the presence of chromophores – light activated compounds – in the material makes the wood look brown. The fibres in the wood, which mainly comprise cellulose, are hollow tube-like structures. The air in these hollow tubes scatters light, further reducing the material’s transparency.</p>
<p>Previous work on making wood transparent has involved <a href="https://chemistry-europe.onlinelibrary.wiley.com/doi/10.1002/cssc.201701089">removing the lignin</a> completely from the structure and replacing it with a resin material. The removal of lignin requires a lot of environmentally harmful chemicals, and it also considerably reduces <a href="https://royalsocietypublishing.org/doi/10.1098/rsta.2017.0182">the mechanical properties</a> of the material. makes it weaker. </p>
<p>The new study, by researchers at the University of Maryland, demonstrates how to make wood transparent using a simple chemical – hydrogen peroxide – commonly used to bleach hair. This chemical modifies the chromophores, changing their structure so they no longer act to absorb light and colour the wood.</p>
<figure class="align-center ">
<img alt="A sunny pine forest with logs in the foreground." src="https://images.theconversation.com/files/383279/original/file-20210209-23-1ttdei1.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/383279/original/file-20210209-23-1ttdei1.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=300&fit=crop&dpr=1 600w, https://images.theconversation.com/files/383279/original/file-20210209-23-1ttdei1.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=300&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/383279/original/file-20210209-23-1ttdei1.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=300&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/383279/original/file-20210209-23-1ttdei1.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=377&fit=crop&dpr=1 754w, https://images.theconversation.com/files/383279/original/file-20210209-23-1ttdei1.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=377&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/383279/original/file-20210209-23-1ttdei1.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=377&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Removing a component of wood, called lignin, can make it see-through.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/forest-pine-spruce-trees-log-trunks-1552199918">Shutterstock/Krasula</a></span>
</figcaption>
</figure>
<p>The chemical can be brushed onto the wood, and then activated using light to produce a brilliant white material – blond wood if you like. The chemical reaction of wood with hydrogen peroxide is well known. It’s the basis for bleaching wood pulp used for paper making – one of the reasons why paper is brilliant white. </p>
<p>The other reason paper is white is because pores or holes in its structure scatter light, just like the hollow cellulose fibres in wood. Filling these fibres with resin reduces that scattering, allowing light to pass through the wood and making it transparent, while retaining its original mechanical properties.</p>
<h2>Wooden windows</h2>
<p>This is a very exciting development that uses well-known chemical reactions of hydrogen peroxide with lignin. The approach could also be applied to large pieces of material, leading to production of transparent building materials offering a real potential to replace glass. </p>
<p>Because the chemical is brushed onto the wood, there might be opportunities for decorative effects to be added to the material. This could make panels of material popular for indoor applications, while also offering additional insulation.</p>
<p>Further work needs to be done to optimise the reaction with wood, and to incorporate it into an industrially automated process. But one day, in the future, you might be sitting in a home or working in a building with wooden windows.</p><img src="https://counter.theconversation.com/content/154981/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Steve Eichhorn receives funding from the Engineering and Physical Sciences Research Council.</span></em></p>Treating wood with bleach can make it transparent.Steve Eichhorn, Professor of Materials Science and Engineering, University of BristolLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1477202020-11-16T19:38:25Z2020-11-16T19:38:25ZAmerican timber industry crippled by double whammy of trade war and COVID-19<figure><img src="https://images.theconversation.com/files/368680/original/file-20201110-23-1qnp50e.jpg?ixlib=rb-1.1.0&rect=45%2C53%2C5010%2C3297&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Douglas fir, a valuable commercial timber, dominates the Oregon coastal forest.</span> <span class="attribution"><a class="source" href="https://unsplash.com/photos/3W6PWBoGpFk">Photo by Eric Muhr on Unsplash</a>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span></figcaption></figure><p>The forestry sector – landowners, logging companies and sawmills – have lost an estimated <a href="https://www.whitehouse.gov/presidential-actions/proclamation-national-forest-products-week-2020/#:%7E:text=Throughout%20the%20western%20United%20States,estimated%20%241.1%20billion%20economic%20loss.">US$1.1 billion in 2020</a>. Devastating wildfires and Hurricane Laura have played a part, but the COVID-19 pandemic has also contributed to <a href="https://extension.tennessee.edu/publications/Documents/W913.pdf">significant losses</a>. If workers are required to stay home, then no trees will be felled or logs sawed into lumber.</p>
<p>These losses have been exacerbated and amplified because of a longstanding trade war that has severely curbed the sale of U.S. forestry products to foreign markets, particularly China.</p>
<p>I am a <a href="https://scholar.google.com/citations?user=3UKxaEcAAAAJ&hl=en&oi=ao">professor of economics</a> with a specialty in international agricultural trade, trade policy and global food demand. My work at the University of Tennessee Institute of Agriculture is informed by my nearly 10 years as a senior economist with USDA researching international trade issues affecting agriculture and forestry.</p>
<h2>The US-China connection</h2>
<p>Forest product exports in the U.S., including logs and lumber, were valued at $9.6 billion in 2018, according to the <a href="https://apps.fas.usda.gov/gats/default.aspx">U.S. Department of Agriculture</a>. Forest products are the third leading U.S. agricultural export sector after soybeans and corn. In 2018, China accounted for nearly $3 billion of <a href="https://apps.fas.usda.gov/gats/default.aspx">U.S. forest product exports</a>.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/365658/original/file-20201026-17-1g3ugde.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Logs stripped of branches and bark are stacked and tagged." src="https://images.theconversation.com/files/365658/original/file-20201026-17-1g3ugde.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/365658/original/file-20201026-17-1g3ugde.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/365658/original/file-20201026-17-1g3ugde.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/365658/original/file-20201026-17-1g3ugde.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/365658/original/file-20201026-17-1g3ugde.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/365658/original/file-20201026-17-1g3ugde.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/365658/original/file-20201026-17-1g3ugde.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">Logs and more logs ready for market, some of which will end up in foreign countries like China for furniture manufacturing.</span>
<span class="attribution"><a class="source" href="https://unsplash.com/photos/TeeK3XdZd54">Photo by Mildly Useful for Unsplash</a>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<p>The forest products relationship between China and the U.S. is complex. The U.S. sells logs and lumber to China; China uses the logs and lumber to produce finished wood products, such as furniture and hardwood flooring; and China exports these finished wood products to the world. Interestingly, the U.S. market is the leading destination for these exports. In 2018, U.S. imports of wooden furniture and other wood products from China exceeded $9 billion, according to the <a href="https://usatrade.census.gov/">U.S. Census Bureau</a>.</p>
<p>This raises an obvious question: Why doesn’t the U.S. simply make furniture and flooring? The answer is wages. The wage differential between U.S. and Chinese workers makes it more profitable to sell logs and lumber to China and then buy back finished wood products. </p>
<p>Since the demand for products like logs and lumber is directly linked to the demand for finished wood products like furniture and flooring, any decline in the latter negatively affects U.S. forest product exports. To say that what happens in China does not necessarily stay in China is an understatement.</p>
<h2>A vulnerable industry takes the hit</h2>
<p>COVID-19 has caused a major disruption on U.S. forest exports and hindered production because of lockdowns, business closures and production stoppages. Many of these supply disruptions started in China, where lumber was being turned into furniture, chairs and other goods where the pandemic began. </p>
<p>However, another major factor has been the interruption of demand because of decreased incomes and delayed purchases by consumers. In the U.S., furniture sales decreased as much as 66% in April 2020 when <a href="https://extension.tennessee.edu/publications/Documents/W913.pdf">stay-at-home orders</a> went into effect. As of August of this year, U.S. imports of wood furniture and other wood products from China were down by nearly <a href="https://usatrade.census.gov/">$2 billion, or 40%</a>.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/365659/original/file-20201026-17-lj28x0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Rows of modern wooden chairs." src="https://images.theconversation.com/files/365659/original/file-20201026-17-lj28x0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/365659/original/file-20201026-17-lj28x0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/365659/original/file-20201026-17-lj28x0.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/365659/original/file-20201026-17-lj28x0.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/365659/original/file-20201026-17-lj28x0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/365659/original/file-20201026-17-lj28x0.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/365659/original/file-20201026-17-lj28x0.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">COVID-19 has hit U.S. furniture sales hard, decreasing the global demand for U.S. timber, a primary input in furniture production.</span>
<span class="attribution"><span class="source">Photo by Nareeta Martin for Unsplash</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<p>Consequently, U.S. forest product exports as of August 2020 had dropped by more than $670 million overall, with exports to China down by more than $100 million. Geographically, most of these losses are in the South, a loss of $246 million, followed by the West, with losses of $183 million, and the Northeast, with losses of $143 million. In addition, these substantial losses are compounded by a multiplier effect that go beyond the raw export numbers. </p>
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<p>In my state of <a href="https://extension.tennessee.edu/publications/Documents/W913.pdf">Tennessee</a>, for instance, the forestry sector provided nearly 100,000 jobs and had an annual economic impact of more than $24 billion in 2017, accounting for nearly 3% of Tennessee’s economy. This, of course, was before the COVID-19 pandemic and the U.S. trade war, which has devastated the <a href="https://extension.tennessee.edu/publications/Documents/W888.pdf">forestry sector</a>. When considering the related activities associated with the forestry sector, such as trucking or equipment, total income and job losses are likely double the direct losses from export sales.</p>
<h2>The economic fallout of the trade war</h2>
<p>Prior to the pandemic, the <a href="https://extension.tennessee.edu/publications/Documents/W888.pdf">U.S.-China trade war</a> had already made the forestry sector vulnerable because of the tariffs that the Chinese government imposed on U.S. timber and the resulting loss in exports. The industry was in a crisis when COVID-19 hit.</p>
<p>In 2018, President Trump ordered that <a href="https://extension.tennessee.edu/publications/Documents/W835.pdf">tariffs be imposed on Chinese imports</a>, including a 10% tariff on furniture and related goods from China. In retaliation, the Chinese government imposed tariffs on many U.S. agricultural goods, including 25% tariffs on U.S. logs and lumber. This double taxation resulted in nearly halving the export to China – from $3 billion in 2018 to $1.6 billion in 2019. The trade war, compounded by COVID-19, has had a major negative effect on forest products export sales – from timber harvest and lumber production to timber exports – which hurts working people including loggers and mill workers. Sawmills, in particular, have taken a serious hit.</p>
<p>How is this related to the current pandemic? In January 2020, the U.S. and China signed the <a href="https://www.fas.usda.gov/topics/china-phase-one-agreement">Phase One Trade Agreement</a>. Based on the details of the agreement, timber and other forest product exports to China were expected to reach more than $4 billion in 2020. The fact that current export sales to China, as of August of 2020, were only $1 billion suggests that COVID-19 is having an even larger impact than the numbers reveal.</p><img src="https://counter.theconversation.com/content/147720/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Andrew Muhammad 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>Wood, a major export of the US, has taken a hit from international tariffs compounded by COVID-19.Andrew Muhammad, Professor of Agriculture and Resource Economics, University of TennesseeLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1358802020-07-16T17:47:47Z2020-07-16T17:47:47ZWooden skyscrapers could transform construction by trapping carbon emissions<figure><img src="https://images.theconversation.com/files/347787/original/file-20200715-23-6g05p8.png?ixlib=rb-1.1.0&rect=83%2C7%2C1089%2C666&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">The Mjøstårnet, an 18-storey mixed-use building constructed with engineered wood, overlooks Norway's largest lake, in Brumunddal.</span> <span class="attribution"><span class="source">(Woodify/YouTube)</span></span></figcaption></figure><p>All over the world, architects and engineers are crafting cutting-edge skyscrapers from one of the most renewable and sustainable materials available to humanity — wood.</p>
<p>For the time being, the <a href="https://materialdistrict.com/article/worlds-tallest-wooden-tower/">tallest wooden building in the world is the Mjøstårnet</a>, an 18-storey building north of Oslo that houses offices, hotel rooms and apartments, and stands just over 85 metres in height. </p>
<p>Canada has several tall wooden towers, including <a href="https://www.theguardian.com/cities/2019/jul/22/canadian-cities-take-wooden-skyscrapers-to-new-heights">Brock Commons at the University of British Columbia</a> (18 storeys; 58 metres) and the <a href="https://www.thinkwood.com/our-projects/origine-tallest-wood-building-in-eastern-north-america">Origine eco-condo development</a> in Québec City (13 storeys). A number of other projects, such as the <a href="https://www.woodbusiness.ca/feds-invest-4-1m-to-build-tall-wood-building-in-toronto/">10-storey Arbour at George Brown College’s Waterfront Campus</a>, are under development. </p>
<p>For some, wood may seem an archaic and even dangerous choice for tall building construction compared to modern alternatives like concrete, steel and glass. But as emissions associated with tall buildings continue to rise, governments at all levels are looking for low-carbon, low-energy alternatives. </p>
<p>In Canada, buildings account for <a href="https://www.canada.ca/en/environment-climate-change/services/environmental-indicators/greenhouse-gas-emissions.html">12.7 per cent of national greenhouse gas emissions</a>. Globally, buildings lead to <a href="https://www.worldgbc.org/sites/default/files/UNEP%20188_GABC_en%20%28web%29.pdf">40 per cent of total emissions</a>. For Canada, a country with abundant wood resources, investing in new tall wooden building construction is an opportunity for sustainable economic growth — but challenges remain. </p>
<h2>Not your average log cabin</h2>
<p>Today’s tall wooden buildings are different from the two-by-four wood framing usually seen in single-family homes or two- to four-storey condominium structures. </p>
<p>So-called “mass timber” construction is derived from old techniques of post-and-beam construction, but uses advanced technologies, including <a href="https://www.vox.com/energy-and-environment/2020/1/15/21058051/climate-change-building-materials-mass-timber-cross-laminated-clt">cross-laminated timbers</a> (CLT) and <a href="https://extension.okstate.edu/fact-sheets/laminated-veneer-lumber-lvl-as-a-construction-material.html">laminated veneer lumber</a> (LVL), which feature layers of wood bonded with adhesives and produced as either beams or panels. Some concrete and steel may be used around elevator shafts or stairwells in mass timber construction, but floors and beams may be made entirely of wood.</p>
<p>Structural wood products like CLT have a <a href="https://cwc.ca/how-to-build-with-wood/building-systems/tall-wood-buildings/">number of advantages</a> in tall wooden building consruction: they are lighter than conventional materials, require less energy to make than either steel or concrete (and thus produce lower emissions), and can sequester carbon. </p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/zY0vFOZ6-us?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">The Mjösa Tower (Mjøstårnet) in Brumunddal, Norway, is — for now — the world’s tallest wooden building.</span></figcaption>
</figure>
<p>Their relative lightness makes it possible to assemble floor and wall sections off-site and ship them to the build site, significantly reducing the amount of building time required. For example, the on-site construction for the Origine project in Québec City was completed in only four months. Adopting tall wooden construction could greatly reduce the amount of disruption — dust, noise and traffic disruptions, for example - that construction brings to the urban landscape.</p>
<h2>Building better, faster and greener</h2>
<p>Prefabrication also means that building structures can be designed to <a href="https://cwc.ca/how-to-build-with-wood/building-systems/tall-wood-buildings/">maximize energy efficiency</a> since individual components can be built precisely in a factory, minimizing errors and ensuring that measurements are exact. </p>
<p>Tall wooden buildings store carbon, preventing it from entering the atmosphere by sequestering it in the building for decades. In contrast, buildings made of steel and concrete generate large amounts of carbon emissions per tonne of material produced. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/347789/original/file-20200715-23-kmlc0m.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A construction worker guides a prefabricated building panel into place." src="https://images.theconversation.com/files/347789/original/file-20200715-23-kmlc0m.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/347789/original/file-20200715-23-kmlc0m.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/347789/original/file-20200715-23-kmlc0m.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/347789/original/file-20200715-23-kmlc0m.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/347789/original/file-20200715-23-kmlc0m.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/347789/original/file-20200715-23-kmlc0m.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/347789/original/file-20200715-23-kmlc0m.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">UBC’s Brock Commons floor structure contains cross-laminated timber (CLT) panels supported on glue-laminated timber (glulam) columns. The prefabricated panels shortened the on-site construction time.</span>
<span class="attribution"><span class="source">(KK Law/Naturally Wood/UBC)</span>, <a class="license" href="http://creativecommons.org/licenses/by-nc/4.0/">CC BY-NC</a></span>
</figcaption>
</figure>
<p>For example, the Brock Commons at UBC sequesters an estimated <a href="https://www.naturallywood.com/sites/default/files/documents/resources/brock_commons_tallwood_house_apr_2018_web_003.pdf">1,753 tonnes of CO2</a>. Research suggests that tall wooden buildings have a <a href="https://doi.org/10.1016/j.jobe.2019.100862">20 per cent reduction</a> in both their carbon and energy footprints. </p>
<p>These types of buildings could be important in helping Canada, and many other countries around the world, achieve net zero performance measures related to energy efficiency and overall carbon emissions that will be required in meeting future climate goals.</p>
<h2>Clear-cut solution?</h2>
<p>The perception remains that tall wooden buildings are less resistant to fire than a typical concrete and steel building. But the designs of these buildings meet stringent fire codes. </p>
<p>The U.S. National Fire Protection Association, in collaboration with Canada’s National Research Council, recently delivered <a href="https://www.nfpa.org/News-and-Research/Data-research-and-tools/Building-and-Life-Safety/Fire-Safety-Challenges-of-Tall-Wood-Buildings-Phase-2">a series of reports</a> on the fire risk associated with tall wooden buildings, with particular focus on the behaviour of cross-laminated timbers or laminated veneer lumber. </p>
<p>Overall, their findings showed that tall wooden buildings can meet <a href="http://wood-works.ca/wp-content/uploads/2019/03/3-TallBuildings_UFVResearchNote_FullReport.pdf">the minimum two-hour fire protection ratings</a> required by most jurisdictions, if proper fireproofing materials and sprinklers are incorporated into the design. In the event of fire, the design minimizes danger in early stages, allowing inhabitants to escape and the fire to be brought under control.</p>
<p>Another challenge tall wooden buildings face is the <a href="https://e360.yale.edu/features/as-mass-timber-takes-off-how-green-is-this-new-building-material">environmental impact they may have on forests</a>. If wood is not sourced from sustainable, responsibly managed forests, any benefit derived from the building itself would be offset by increased deforestation and habitat loss. </p>
<p>A number of tools, like the certification programs run by the <a href="https://ca.fsc.org/en-ca">Forest Stewardship Council</a> or the <a href="https://www.pefc.org/">Programme for the Endorsement of Wood Certification</a> provide important third-party verification that forest harvests are done within a sustainable management regime; these schemes are constantly being reviewed to consider all aspects of forest sustainability, including carbon depletion in forest soils and impacts to biodiversity. As tall wooden buildings take off, it is critical that the wood used in construction be sourced in an increasingly sustainable fashion.</p>
<p>Tall wooden buildings are likely to play an increasingly important role in our carbon mitigation strategies. Recent work suggests that shifting to wooden construction could act as an <a href="https://doi.org/10.1038/s41893-019-0462-4">ever-increasing carbon sink</a>, allowing more and more carbon to be sequestered safely in useful applications. </p>
<p>The crown for the tallest wood building will be hard to keep. In Tokyo, a proposal for a <a href="https://www.cnbc.com/2018/02/20/worlds-tallest-wooden-skyscraper-japan.html">350-metre tall</a>, 70-storey building is currently vying for the title. </p>
<p>As architects, engineers and tradespeople become comfortable with these materials, tall wooden buildings will increasingly become a part of the urban landscape around the world.</p><img src="https://counter.theconversation.com/content/135880/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Warren Mabee receives funding from the Natural Sciences and Engineering Research Council and from the Canada Research Chairs Foundation.</span></em></p>Buildings account for a large proportion of greenhouse gas emissions globally. Sustainably sourced wood could be a better building material.Warren Mabee, Director, Queen's Institute for Energy and Environmental Policy, Queen's University, OntarioLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1318752020-02-21T12:33:16Z2020-02-21T12:33:16ZAir pollution kills thousands of Americans every year – here’s a low-cost strategy to reduce the toll<figure><img src="https://images.theconversation.com/files/316033/original/file-20200218-11000-371mgc.jpg?ixlib=rb-1.1.0&rect=49%2C0%2C5472%2C3637&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Reducing fine particle air pollution from petrochemical complexes, like this one near the Houston Ship Channel in Texas, is a low-cost way to lower air pollution mortality.</span> <span class="attribution"><a class="source" href="http://www.apimages.com/metadata/Index/Harvey/928217f2b7374673bac894a63d7c7535/36/0">AP Photo/David J. Phillip</a></span></figcaption></figure><p>About <a href="https://doi.org/10.1016/S0140-6736(18)32225-6">1 of every 25 deaths</a> in the U.S. occurs prematurely because of exposure to air pollution. Dirty air kills roughly 110,000 Americans yearly, which is more than <a href="https://www.cdc.gov/nchs/data/nvsr/nvsr67/nvsr67_05.pdf">all transportation accidents and shootings combined</a>. </p>
<p>When the U.S. Environmental Protection Agency weighs decisions about air pollution regulations, it typically selects candidate actions from one or more sectors, such as electric power generation and industry. For each strategy considered, the agency carefully estimates the costs and benefits, then decides which actions to pursue. </p>
<p>We study <a href="https://sph.unc.edu/adv_profile/jason-west-phd/">air pollution</a> and <a href="https://scholar.google.com/citations?user=SDTX4PQAAAAJ&hl=en">options for reducing it</a>. In a <a href="https://doi.org/10.1038/s41467-020-14783-2">newly published study</a>, we flipped the traditional approach around by starting with the goal of finding emission control actions, among all sources, that could save a specified number of lives for the lowest cost. In doing so, we identified a set of low-cost actions to reduce air pollutant emissions from highly polluting industrial and residential sources, such as residential wood-burning furnaces, that can provide highly cost-effective health benefits.</p>
<p>The U.S. has made <a href="https://gispub.epa.gov/air/trendsreport/2019/#summary">tremendous progress</a> in reducing air pollution since 1990, and this has produced <a href="https://doi.org/10.5194/acp-18-15003-2018">significant public health improvements</a>. But air pollution still imposes a serious health burden on the U.S. population, and there are signs that past progress in improving air quality <a href="https://www.nytimes.com/interactive/2019/10/24/climate/air-pollution-increase.html?action=click&module=Top%20Stories&pgtype=Homepage">may now be</a> <a href="https://www.popsci.com/story/environment/air-pollution-gains-slow-report-2018/">leveling off</a>. New ways of analyzing actions to control air pollution and its health impacts can help. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/316034/original/file-20200218-11000-10ygfvw.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/316034/original/file-20200218-11000-10ygfvw.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/316034/original/file-20200218-11000-10ygfvw.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/316034/original/file-20200218-11000-10ygfvw.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/316034/original/file-20200218-11000-10ygfvw.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/316034/original/file-20200218-11000-10ygfvw.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/316034/original/file-20200218-11000-10ygfvw.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/316034/original/file-20200218-11000-10ygfvw.png?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 number of bad air days in 35 major U.S. cities has plateaued since 2013.</span>
<span class="attribution"><a class="source" href="https://gispub.epa.gov/air/trendsreport/2019/#unhealthy_aq_days">USEPA</a></span>
</figcaption>
</figure>
<h2>An alternative approach</h2>
<p>Under the 1970 Clean Air Act, it is the EPA’s job to set <a href="https://www.epa.gov/criteria-air-pollutants/naaqs-table">National Ambient Air Quality Standards</a>. These regulations limit concentrations of six major air pollutants that harm public health and the environment. Then each state adopts actions that will meet these standards, such as reducing emissions from power plants or large industries. </p>
<p>The EPA also sets limits on emissions from some specific sources over which it has legal authority, including new power plants and motor vehicles. In doing so, the agency aims for air that is considered healthy for all Americans to breathe. </p>
<p>For each strategy considered, the EPA often runs a full cost-benefit analysis. This approach requires a complex atmospheric model to estimate how each proposed action will affect air pollutant concentrations, and the health impacts that will result. This limits the number of options that can be considered. </p>
<p>Our study focused on fine particulate matter, known as PM2.5. We created a framework that simplified the complexity of the atmosphere and air pollution’s health impacts. For each U.S. state we calculated <a href="https://doi.org/10.1038/s41467-020-14783-2">impact factors</a>, which represent deaths related to PM2.5 exposure per ton of emissions of different chemical components from different sources. Then we fed these impact factors into an economic model of the U.S. energy system, allowing the model to calculate deaths for any strategy.</p>
<p>Next we set a limit on total deaths caused by PM2.5, and let the model select the least expensive set of actions that would meet energy needs – an important factor because energy use is a major air pollution source - while keeping PM2.5-related deaths below our ceiling. Our model projected future scenarios to 2050, so we considered different ceilings at various points in time, and observed the actions the model selected. </p>
<p>This alternative approach has the advantage of considering a wide range of possible control strategies that affect many different sources. It prioritizes the actions that most cost-effectively reduce premature deaths. Further, by considering these actions in the context of the broader energy system, we can include actions like fuel switching and energy efficiency as alternatives, and quantify consequences of actions throughout the U.S. energy system. </p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/GVBeY1jSG9Y?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">How PM2.5 affects your body once it’s inhaled.</span></figcaption>
</figure>
<h2>High particulate emitters</h2>
<p>Using this approach, we pinpointed a set of sources whose emissions contribute disproportionately to PM2.5 mortality impacts. They include factories and other industrial facilities powered by coal and oil, and wood-fired residential furnaces. Emissions from these sources are rising and <a href="https://doi.org/10.1088/1748-9326/ab59cb">may continue to increase</a> in the future without additional controls. </p>
<p>Our model showed that reducing emissions from these sources – mainly by electrifying them – could cut projected national air pollution-related deaths in 2050 in half very cost-effectively. Overall national health benefits from these reductions would be roughly seven times the cost of the pollution controls. As many studies have found, air pollution controls <a href="https://www.epa.gov/clean-air-act-overview/benefits-and-costs-clean-air-act-1990-2020-second-prospective-study">tend to be very cost-effective</a> because these emissions cause people to die prematurely through cardiovascular diseases, stroke, lung cancer and other long-term illnesses.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/316205/original/file-20200219-10995-zgb8sy.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/316205/original/file-20200219-10995-zgb8sy.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/316205/original/file-20200219-10995-zgb8sy.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=368&fit=crop&dpr=1 600w, https://images.theconversation.com/files/316205/original/file-20200219-10995-zgb8sy.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=368&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/316205/original/file-20200219-10995-zgb8sy.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=368&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/316205/original/file-20200219-10995-zgb8sy.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=463&fit=crop&dpr=1 754w, https://images.theconversation.com/files/316205/original/file-20200219-10995-zgb8sy.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=463&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/316205/original/file-20200219-10995-zgb8sy.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=463&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Reductions in the costs of PM2.5-related deaths due to emission reductions from each state, from a scenario that cuts projected national PM2.5-related deaths in 2050 in half.</span>
<span class="attribution"><a class="source" href="https://doi.org/10.1038/s41467-020-14783-2">Ou et al., 2020.</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<p>Our study shows that this approach would reduce PM2.5-related emissions in each state. Progress would be greatest in northern and eastern states, including Ohio and Pennsylvania. These regions have many large industrial sources and are densely populated, which means that many people benefit from cleaner air. </p>
<p>Ohio has the largest potential for cost-effectively reducing PM2.5 deaths through cutting industrial coal emissions. California would benefit most from controls on residential wood burning, and Texas would see the greatest reductions in emissions from large petrochemical industries. </p>
<p>We also found that these actions had little influence on overall energy usage in the U.S., and therefore little effect on greenhouse gas emissions. This was interesting because previous research has found that most initiatives to reduce greenhouse gases – which typically involve switching to less-polluting fuels, such as going from coal to natural gas to renewables – <a href="https://doi.org/10.1038/nclimate2009">also reduce air pollutant emissions</a>, with significant <a href="https://iopscience.iop.org/article/10.1088/1748-9326/aa8f76">benefits for public health</a>. But the opposite is not true: Low-cost air pollution controls do not appear to have a big influence on U.S. greenhouse gas emissions.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/316515/original/file-20200220-92541-1q5ey6b.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/316515/original/file-20200220-92541-1q5ey6b.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/316515/original/file-20200220-92541-1q5ey6b.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=435&fit=crop&dpr=1 600w, https://images.theconversation.com/files/316515/original/file-20200220-92541-1q5ey6b.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=435&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/316515/original/file-20200220-92541-1q5ey6b.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=435&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/316515/original/file-20200220-92541-1q5ey6b.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=547&fit=crop&dpr=1 754w, https://images.theconversation.com/files/316515/original/file-20200220-92541-1q5ey6b.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=547&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/316515/original/file-20200220-92541-1q5ey6b.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=547&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 costs and health benefits of identified low-cost actions to reduce projected national 2050 PM2.5-related deaths by 10% to 50%.</span>
<span class="attribution"><span class="source">Yang Ou</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<h2>Looking forward to cleaner air</h2>
<p>Our approach finds the least-cost way of reducing the health impacts of fine particle pollution among all Americans. But it does not ensure that current standards will be met everywhere. One limitation of our method is that we analyzed emissions at the state level, but our current model does not permit us to look more closely at air quality and health impacts for individual urban areas within states that exceed fine particle standards. </p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/316036/original/file-20200218-11011-1i4lb41.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/316036/original/file-20200218-11011-1i4lb41.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/316036/original/file-20200218-11011-1i4lb41.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=715&fit=crop&dpr=1 600w, https://images.theconversation.com/files/316036/original/file-20200218-11011-1i4lb41.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=715&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/316036/original/file-20200218-11011-1i4lb41.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=715&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/316036/original/file-20200218-11011-1i4lb41.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=898&fit=crop&dpr=1 754w, https://images.theconversation.com/files/316036/original/file-20200218-11011-1i4lb41.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=898&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/316036/original/file-20200218-11011-1i4lb41.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=898&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Inefficient wood stoves and wood-burning furnaces are major fine particle sources.</span>
<span class="attribution"><a class="source" href="https://www.publichealthmdc.com/environmental-health/air-quality/outdoor-air-quality/wood-smoke-pollution">Madison & Dane County Public Health</a></span>
</figcaption>
</figure>
<p>Still, our methods offer another tool that the EPA and states can use to help in planning air quality improvements, and the actions identified as being cost-effective for improving health can be compared with those currently being pursued. Spotlighting alternative pollution reduction options can help federal and state regulators make decisions about energy resources and their environmental and health impacts for the coming decades. </p>
<p>As natural gas and renewable energy prices fall, energy industries are in the <a href="https://theconversation.com/fight-or-switch-how-the-low-carbon-transition-is-disrupting-fossil-fuel-politics-122376">midst of a transition</a> driven by new technologies and changing economics. As this shift takes place, it is important to consider how to meet new energy demands while reducing greenhouse emissions and the health impacts of air pollutants. We hope our methods will be useful in informing these decisions in the U.S. and elsewhere. </p>
<p>[<em>Deep knowledge, daily.</em> <a href="https://theconversation.com/us/newsletters?utm_source=TCUS&utm_medium=inline-link&utm_campaign=newsletter-text&utm_content=deepknowledge">Sign up for The Conversation’s newsletter</a>.]</p><img src="https://counter.theconversation.com/content/131875/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Jason West receives funding from the EPA, NASA, NSF, the Donald and Jennifer Holzworth Faculty Acceleration Fund in Climate Change, and the State of North Carolina. </span></em></p><p class="fine-print"><em><span>Yang Ou was supported by the Research Participation Program at the Center for Environmental Measurement and Modeling, U.S. Environmental Protection Agency, administered by the Oak Ridge Institute for Science and Education (ORISE).</span></em></p>A new study takes an innovative approach to reducing fine particle air pollution and spotlights key sources: factories that burn coal and oil, petrochemical plants and burning wood for home heating.Jason West, Professor of Environmental Sciences and Engineering, University of North Carolina at Chapel HillYang Ou, Postdoctoral Associate, Pacific Northwest National LaboratoryLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1263462019-11-21T19:32:51Z2019-11-21T19:32:51ZCurious Kids: why does wood crackle in a fire?<figure><img src="https://images.theconversation.com/files/300013/original/file-20191104-88428-inlkf3.jpg?ixlib=rb-1.1.0&rect=31%2C0%2C3464%2C2307&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">If you've ever put wet wood on to a fire, you may have noticed it makes a lot more noise than dry wood.
</span> <span class="attribution"><span class="source">Shutterstock</span></span></figcaption></figure><hr>
<blockquote>
<p><strong>Why does wood crackle in a fire? – Rocco, age 6 (nearly 7!)</strong></p>
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<p><a href="https://theconversation.com/au/topics/curious-kids-36782"><img src="https://images.theconversation.com/files/291898/original/file-20190911-190031-enlxbk.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=90&fit=crop&dpr=1" width="100%"></a></p>
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<p>Hi Rocco, that’s a great question. I love sitting in front of a fire, listening to it crackle and pop. </p>
<p>These noises are caused by pockets of trapped steam suddenly escaping, making a mini explosion! </p>
<p>To know why this happens, we need to understand what happens when you place a wooden log on a fire. First, the wood starts getting hotter. Inside the wood are pockets of trapped water and tree sap, which is the sticky stuff you sometimes see on trees.</p>
<p>In the same way water in a kettle heats up and turns into steam, so does the water trapped inside the log. So as the fire gets hotter, the water and sap inside start to boil and turn into gas. As the fire gets even hotter, these gases start to take up more space and expand (get bigger).</p>
<h2>How do the gases burst out?</h2>
<p>While the water and sap turn into steam, something also happens to the wood. Wood contains something called cellulose, which is the stuff that plants are mostly made out of.</p>
<p>When cellulose is heated, it starts to break down, or “decompose”. If you’ve ever forgotten an apple in your lunchbox over the weekend, and it turns brown and yucky, that means it has decomposed. When something in nature (like a piece of fruit) decomposes, it changes. </p>
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<strong>
Read more:
<a href="https://theconversation.com/curious-kids-when-i-swipe-a-matchstick-how-does-it-make-fire-116673">Curious Kids: when I swipe a matchstick how does it make fire?</a>
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<p>When wood in a fire gets hot enough, the cellulose inside starts to turn into gas. This is when we see smoke coming out of the wood, sometimes even before that piece of wood has burst into flames. </p>
<p>The flames happen when the gas escaping from the wood starts to mix with the oxygen in the air. Oxygen is like food for fires – it makes them burn really bright.</p>
<p>As wood burns, the mix of expanding gases and cellulose breaking down makes the pockets of trapped steam burst open from the wood, one by one. This is why you hear the crackling and popping noises. </p>
<p>So the more water and sap there is inside the wood, the noisier the fire will be. If you’ve ever put damp wood on a fire, you may have noticed it makes a lot more noise than really dry wood.</p>
<h2>How does the wood get water inside it?</h2>
<p>But how does water and sap get inside wood in the first place?</p>
<p>Well, wood isn’t quite as solid as it looks. It has many tiny holes, too small for our eyes to see, and these holes have water and sap inside them. </p>
<p>We know wood comes from trees. And when trees are alive, they stay healthy by carrying water up their trunk through these tiny holes, which are called xylem vessels. When the tree is chopped down to make firewood, there is still water trapped inside these xylem vessels. </p>
<p>There are other ways water can get inside wood. If firewood is left out in the rain, it can soak up water that way. Or sometimes insects make small holes in the wood, which let water in.</p>
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<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/curious-kids-how-do-bushfires-start-116664">Curious Kids: how do bushfires start?</a>
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<p>Sitting in front of a fire watching the flames and listening to the wood crackle and pop can be fun. Most of the time the mini explosions of the steam escaping are small. </p>
<p>But sometimes they can be big, and might even cause small chunks of burning wood to fly out of the fire! This is why it’s important always to keep a safe distance from a fire, or to use a fireguard.</p>
<hr>
<p><em>The author thanks her nephews Aldous Nolan (6) and Fergus Nolan (5) for helping to improve this answer.</em></p>
<hr>
<p><em>Hello, curious kids! Have you got a question you’d like an expert to answer? Ask an adult to send your question to curiouskids@theconversation.edu.au</em></p><img src="https://counter.theconversation.com/content/126346/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Rachael Helene Nolan receives funding from the NSW Bushfire Risk Management Research Hub, funded through the Department of Planning, Industry and Environment (formerly OEH) and has previously received funding from the Australian Government's Innovation Connections programme in conjunction with GreenCollar.</span></em></p>Water and sap inside the wood make mini explosions as they turn into gas and burst out. That’s why damp wood makes the noisiest fires.Rachael Helene Nolan, Postdoctoral research fellow, Western Sydney UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1225602019-08-29T10:16:31Z2019-08-29T10:16:31ZAfrica’s Mukula trees score a victory as trade is put under closer scrutiny<figure><img src="https://images.theconversation.com/files/289865/original/file-20190828-184252-of5qb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Rosewood is coveted for its colour </span> <span class="attribution"><span class="source">Winai Tepsuttinun/Shutterstock</span></span></figcaption></figure><p><em>CITES – the Convention on International Trade in Endangered Species of Wild Fauna and Flora – <a href="https://www.cites.org/eng/CITES_conference_responds_to_extinction_crisis_by_strengthening_international_trade_regime_for_wildlife_28082019">has decided</a> to include Mukula trees, one of many rosewood species, in its Annex II listing. Species covered by CITES are listed in three Annexes according to how much protection they need. Annex II includes species not directly threatened with extinction, but in which trade must be controlled to ensure their survival. The Conversation Africa’s Moina Spooner asked Paolo Cerutti and Nils Bourland about the decision.</em></p>
<p><strong>Why is Mukula wood so sought after?</strong></p>
<p>Rosewood is an informal term which refers to a group of hardwood species that are red in colour and widely used in furniture processing. Historically, the “real” rosewood belonged to the <em>Dalbergia</em> genus as found in Brazil, India or Madagascar. But with time, the name has been commonly used to group strong woods with a reddish colour. </p>
<p>Demand for rosewoods has been growing for several years, particularly in Asia. China is one of the biggest rosewood consumers and, since 2000, has established an <a href="http://hongzhanju.net/nd.jsp?id=114">official list</a> of <a href="https://www.forest-trends.org/wp-content/uploads/imported/tropical-hardwood-flows-in-china-v12_12_3_2013-pdf.pdf">33 tree species</a> harvested across the tropics in Africa (five), Latin America (seven) and Asia (21), and imported and traded under the “Rosewood” name. </p>
<p>The wood fetches very high prices in China as it’s used to make <a href="https://www.forest-trends.org/publications/chinas-hongmu-consumption-boom/"><em>hongmu</em></a> – antique red-wood furniture. <em>Hongmu</em> was historically used by the imperial elite and is now coveted by China’s rising wealthy middle-class.</p>
<p>Because the usual rosewood tree species – like the <em>Dalbergias</em> – have been over-harvested for decades and are now <a href="https://www.wood-database.com/hardwoods/fabaceae/dalbergia/">endangered</a>, traders have tried to diversify, using trees which could provide similar colours and strength. </p>
<p>Mukula – <em>Pterocarpus tinctorius</em> – is <a href="http://www.ville-ge.ch/musinfo/bd/cjb/africa/details.php?langue=fr&id=62768">the local</a> name for rosewood harvested in Angola, Burundi, the Democratic Republic of the Congo, Malawi, Mozambique, and Tanzania. </p>
<p>Even though it is not one of the tree species labelled as “rosewood” under China’s official list, traders and consumers still want it for its colour and strength. When freshly cut and debarked, Mukula’s timber has a bright brown-reddish colour – produced by oils and chemicals it contains – which turns to darker brown with time and exposure to light. These oils are also what make the wood durable. </p>
<p>As a result Mukula became part of the <a href="https://www.forest-trends.org/wp-content/uploads/imported/tropical-hardwood-flows-in-china-v12_12_3_2013-pdf.pdf">wider rosewood trade</a> that affects much of southeast Asia and parts of Africa and South America.</p>
<p><strong>What was the basis of the CITES decision to control the trade in mukula?</strong></p>
<p>Government seizures of illegally harvested Mukula started to be reported in the media, mostly in Zambia, <a href="http://www.daily-mail.co.zm/mukula-auction-raises-k7m/">about</a> five years ago. </p>
<p>But the seizures didn’t stop traders; the volumes harvested and traded increased year after year. Eventually, <a href="https://theconversation.com/why-zambia-has-not-benefitted-from-its-rosewood-trade-with-china-98092">media</a> and political attention started to flag the negative environmental and socio-economic impacts of the trade, bringing Mukula to the attention of CITES. </p>
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<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/why-zambia-has-not-benefitted-from-its-rosewood-trade-with-china-98092">Why Zambia has not benefitted from its rosewood trade with China</a>
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<p>Mukula in Zambia mainly <a href="https://pdfs.semanticscholar.org/2a87/22f4edc1417a997460046d56070506955ba0.pdf">occurs</a> in the country’s miombo fragile woodlands. It’s an area of great importance for local communities, because it’s a <a href="https://www.intechopen.com/books/biodiversity-in-ecosystems-linking-structure-and-function/miombo-woodlands-research-towards-the-sustainable-use-of-ecosystem-services-in-southern-africa">source of</a> livelihoods for them. It also hosts flagship fauna species, including monkeys, that feed on its fruits. </p>
<p><strong>How will the decision now be implemented and which countries does it affect most?</strong></p>
<p>Mukula logs, sawn wood, veneer sheets and plywood are affected by this listing. It is important to remember that this decision doesn’t ban the trade of Mukula. Instead, it seeks to increase levels of monitoring so that we can be more and better informed about illegal trade and over-harvesting.</p>
<p>After the decision enters into force, all countries exporting Mukula will have to conduct what is known in CITES as “Non-Detriment Findings”. Range States – Angola, Burundi, the Democratic Republic of the Congo, Malawi, Mozambique, and Tanzania – are immediately concerned.</p>
<p>This means that sustainability, legality and the ability to trace the wood from stump to market must be guaranteed and CITES permits will have to be issued when the species is traded. The permit is issued if it is demonstrated that the traded volume – the number of felled trees – does not threaten the survival of the species at the place of harvest in natural forests. Planted species are not considered.</p>
<p>In addition, the convention requires that exporting and importing countries report to the CITES secretariat, which enters the information into a specific database for global monitoring. The CITES’ Plant Committee is then mandated to conduct periodic reviews to detect abnormal situations, for example discrepancies in trade statistics.</p>
<p>There are several other mechanisms which allow irregularities in trade to be monitored at national and international levels. Civil society, NGOs and researchers can also play a great role, drawing attention on unclear situations and illegal activities.</p>
<p><strong>Despite different bans and restrictions Mukula harvest and trade hasn’t stopped. What will be the challenges in implementing this decision?</strong></p>
<p>Various timber-producing countries have adopted harvesting and/or trading bans on species of particular socio-economic and environmental value. Yet bans can only be as good as their enforcement and monitoring are. Many countries do adopt bans but not all enforce and monitor their impact. These are sovereign decisions, generally dictated more by the politics of the day than by any serious attempt at understanding their environmental consequences.</p>
<p>Mukula in Zambia is a clear example of this. Multiple bans <a href="https://www.africanfarming.com/zambia-conditionally-lifts-ban-mukula-trade/">have been</a> adopted and lifted in recent years. But these decisions were dictated less by environmental considerations than political ones. </p>
<p>For example, at the beginning of 2016, a “Mukula timber harvesting and movement ban” was issued, then lifted in July 2016, and then reinstated at the beginning of 2017. Yet during all those years, no new assessment was conducted on the ground about the sustainable harvesting levels of Mukula, so traders were able to continue increasing the harvested volumes irrespective of the bans.</p>
<p>The Annex II listing is a great outcome for Mukula. It adds to the force of national decisions, like bans, and makes cheating much more difficult. It also gives it international attention.</p>
<p>But to beat the unsustainable harvesting of rosewoods, we need to aim for even more encompassing solutions. For example, CITES should consider a genus-wide listing which includes some <em>Pterocarpus</em> species, so that traders cannot just as easily move on to the next Rosewood tree and deplete it.</p><img src="https://counter.theconversation.com/content/122560/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Part of the research referenced in this article has been supported by the UK Economic and Social Research Council and the Department of International Development through the project ‘Natural Resources, Rural Poverty and China-Africa Trade: Equity and Sustainability in Informal Commodities Value Chains’ (ES/M00659X/1) and Danida (Denmark), Irish Aid and Sida (Sweden). It is also part of the CGIAR Research Programme on Forests, Trees and Agroforestry (FTA), with support from the CGIAR Fund Donors: <a href="http://www.cgiar.org/our-funders">www.cgiar.org/our-funders</a> </span></em></p><p class="fine-print"><em><span>Nils Bourland works for the Wood Biology Service of the Royal Museum for Central Africa (Tervuren, Belgium), the Center for International Forestry Research (Bogor, Indonesia) and Research and Solutions Development (Kigali, Rwanda).</span></em></p>CITES’ decision seeks to increase levels of monitoring so that we can be more and better informed about the illegal trade of Mukula and over-harvesting.Paolo Omar Cerutti, Senior Scientist, Centre for International Forestry ResearchNils Bourland, Senior Associate, Centre for International Forestry ResearchLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/931152018-04-24T10:43:43Z2018-04-24T10:43:43ZGlobal timber trafficking harms forests and costs billions of dollars – here’s how to curb it<figure><img src="https://images.theconversation.com/files/216010/original/file-20180423-94115-1pps3wd.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Illegally logged rosewood in Antalaha, Madagascar, 22 February 2005.</span> <span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/File:Illegal_export_of_rosewood_001.jpg">Erik Patel</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span></figcaption></figure><p>If a tree falls in the forest, do you care how it was brought down?</p>
<p>Few people think about where the wood in their furniture, floors or doors comes from or how it got there. And few would guess that one of the most illegally traded wild products worldwide is a tree, <a href="http://www.unodc.org/unodc/en/data-and-analysis/wildlife.html">rosewood</a> (<em>Dalbergia</em>).</p>
<p>Rosewood is so widely trafficked it is called “<a href="http://www.wri.org/blog/2016/10/un-issues-new-protections-rosewood-trees-ivory-forest">the ivory of the forest</a>.” Its rich reddish-brown timber is used to make furniture, flooring and musical instruments. Yet many of the trees that produce it are <a href="https://reverb.com/news/new-cites-regulations-for-all-rosewood-species">threatened</a> and internationally <a href="https://www.theguardian.com/environment/2016/sep/29/wildlife-summit-cracks-down-on-illegal-rosewood-trade">protected</a>.</p>
<p>Rosewood is an extreme example of a <a href="https://grid.cld.bz/Green-Carbon-Black-Trade">wider problem</a>. Globally, 15 to 30 percent of timber is taken illegally. According to Interpol, the illegal timber trade is worth <a href="https://www.interpol.int/Crime-areas/Environmental-crime/Projects/Project-Leaf">US$50 billion to $150 billion</a> annually.</p>
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<iframe width="440" height="260" src="https://www.youtube.com/embed/BxSUH1KlMQ8?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Illegal logging has many harmful impacts, from deforestation to impoverishment of local communities.</span></figcaption>
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<p>This complex issue will not be solved overnight. But I believe that social science can help curb it by showing the damage illegal timber trade causes to humans and forests, and by stigmatizing the sale and purchase of contraband wood products.</p>
<h2>The role of rules</h2>
<p><a href="https://scholar.google.com/citations?user=XT-t5bgAAAAJ&hl=en">My research</a> uses social science to address conservation issues like <a href="http://bit.ly/WallenDaut2018">wildlife trafficking</a> and <a href="https://doi.org/10.1080/10871209.2018.1434705">invasive species</a>. I focus on the role of <a href="https://dx.doi.org/10.1073%2Fpnas.1704451114">norms</a> and rules, which guide human <a href="https://global.oup.com/academic/product/who-rules-the-earth-9780199896615">behavior</a> by signaling whether an action is common or approved. When people or organizations <a href="https://doi.org/10.1177/0956797617719950">know</a> that doing something is unacceptable and punishable, they are more likely to refrain from it.</p>
<p>Today, many rules designed to protect against timber trafficking are either <a href="https://nyti.ms/2Fkcpbi">not strict enough</a> or <a href="https://e360.yale.edu/features/greenwashed-timber-how-sustainable-forest-certification-has-failed">poorly enforced</a>. This signals that illegal activity can occur with impunity, although some nations are tightening up regulations in an effort to curb the problem. </p>
<h2>A global trade</h2>
<p>Illegal timber is estimated to account for <a href="http://wwf.panda.org/about_our_earth/deforestation/deforestation_causes/%20illegal_logging/">50 to 90 percent</a> of wood harvested from Amazonia, central Africa and Southeast Asia. <a href="https://www.interpol.int/Crime-areas/Environmental-crime/Projects/Project-Leaf">Interpol</a> estimates that 40 to 60 percent of timber exports from Indonesia, 25 percent from Russia and 70 percent from Gabon are illegal. In 2016 the U.S. Trade Representative’s Office estimated that 90 percent of U.S. <a href="https://ustr.gov/sites/default/files/Timber-Committee-Report-8172016.pdf">timber imports from Peru</a> were sourced from illegal logging.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/216012/original/file-20180423-94118-3wsg8c.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/216012/original/file-20180423-94118-3wsg8c.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/216012/original/file-20180423-94118-3wsg8c.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=666&fit=crop&dpr=1 600w, https://images.theconversation.com/files/216012/original/file-20180423-94118-3wsg8c.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=666&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/216012/original/file-20180423-94118-3wsg8c.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=666&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/216012/original/file-20180423-94118-3wsg8c.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=837&fit=crop&dpr=1 754w, https://images.theconversation.com/files/216012/original/file-20180423-94118-3wsg8c.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=837&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/216012/original/file-20180423-94118-3wsg8c.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=837&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 majority of illegal logging takes place in the tropical forest of the Amazon, central Africa and Southeast Asia. Recent studies reveal that illegal logging accounts for as much as 50–90% of total production from some key tropical forest countries.</span>
<span class="attribution"><a class="source" href="http://www.grida.no/resources/6961">GRID-Arendal</a>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<p>North America is not exempt. Tree poachers target centuries-old cedars and redwoods in <a href="https://www.smithsonianmag.com/science-nature/how-thousand-year-old-trees-became-new-ivory-180963365">British Columbia</a> and the <a href="https://www.hcn.org/issues/49.5/busting-the-tree-ring">Pacific Northwest</a>.</p>
<p>Illegal activities <a href="https://globalforestatlas.yale.edu/forest-use-logging/logging/illegal-logging">lower global timber prices</a> by 7 to 16 percent, costing source nations up to $5 billion in <a href="http://www.worldbank.org/en/news/feature/2013/01/29/sustaining-forests-livelihoods-changing-world">lost annual revenue</a>. This would suggest governments have a significant <a href="https://www.illegal-logging.info/sites/default/files/uploads/1_AF_and_PA_summary.pdf">incentive</a> to act. But weak regimes, corruption and unresponsive agencies – particularly in source countries – are <a href="http://www.oaklandinstitute.org/sites/oaklandinstitute.org/files/OI_Report_On_Our_Land.pdf">failing</a> to curb timber trafficking.</p>
<h2>Improving enforcement</h2>
<p>To protect forests and guide timber use, governments create <a href="https://europa.eu/capacity4dev/public-flegt/documents/comparison-illegal-logging-laws-eu-us-australia-and-japan">rules</a>. International treaties and trade regulations <a href="https://www.fws.gov/international/permits/by-species/wood-and-other-tree-products.html">restrict</a> timber imports based on quantity or species. Domestic <a href="http://www.nnrg.org/resources/template-plans/">management plans</a>, <a href="http://www.sfiprogram.org/files/pdf/addressing-illegal-logging-through-sfi-certification/">certification programs</a> and <a href="http://www.dovetailinc.org/report_pdfs/2015/dovetailtradepolicyimpacts0515.pdf">procurement policies</a> dictate how timber should be harvested, bought and sold.</p>
<p>But the effectiveness of these rules often depends on <a href="https://doi.org/10.1080/08941920.2016.1209266">sanctions</a> that penalize rule violators. Many <a href="http://www.worldbank.org/en/news/feature/2013/01/29/sustaining-forests-livelihoods-changing-world">source countries</a> have little capacity to effectively monitor forests or enforce penalties for illegal logging. This makes it easy for traffickers to avoid being caught.</p>
<p>Countries with few or weak regulations also act as trans-shipment points. For example, traffickers send timber from <a href="https://news.nationalgeographic.com/2017/08/wildlife-watch-illegal-logging-papua-new-guinea/">Papua New Guinea</a> to nations like China that do not ban illegal timber. It is then processed and exported as finished products to the United States.</p>
<p>Over the past decade the United States has acted to bolster rules and sanctions against illegal timber purchases. Notably, in 2008 Congress amended the <a href="https://www.aphis.usda.gov/aphis/ourfocus/planthealth/import-information/sa_lacey_act/ct_lacey_act">Lacey Act</a>, which prohibits trade in illegal wildlife, fish and plants, to include <a href="https://doi.org/10.1016/j.forpol.2014.10.002">timber</a>.</p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/216013/original/file-20180423-94149-66k4qi.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/216013/original/file-20180423-94149-66k4qi.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/216013/original/file-20180423-94149-66k4qi.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=719&fit=crop&dpr=1 600w, https://images.theconversation.com/files/216013/original/file-20180423-94149-66k4qi.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=719&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/216013/original/file-20180423-94149-66k4qi.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=719&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/216013/original/file-20180423-94149-66k4qi.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=903&fit=crop&dpr=1 754w, https://images.theconversation.com/files/216013/original/file-20180423-94149-66k4qi.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=903&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/216013/original/file-20180423-94149-66k4qi.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=903&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 Stewardship Council certification indicates that wood comes from forests and supply chains that are managed responsibly and according to the laws of the producer country.</span>
<span class="attribution"><a class="source" href="https://en.wikipedia.org/wiki/Forest_Stewardship_Council">FSC</a>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<p>Several high-profile sanctions followed. <a href="https://www.justice.gov/opa/pr/lumber-liquidators-inc-sentenced-illegal-importation-hardwood-and-related-environmental">Lumber Liquidators</a> was fined $13 million in 2011 for selling flooring made from illegal Russian timber. In 2015, the <a href="https://www.globalwitness.org/en/campaigns/forests/buyers-good-faith/">Yacu Kallpa</a>, a Peruvian vessel carrying illegal timber destined for Houston, was detained by <a href="https://ojo-publico.com/especiales/madera-ilegal/the-odyssey-of-the-yacu-kallpa/">Mexico</a>. And in late 2017 the U.S. trade representative blocked timber imports from <a href="https://ustr.gov/about-us/policy-offices/press-office/press-releases/2017/october/ustr-announces-unprecedented-action">Peru</a>.</p>
<p>But until source countries can effectively monitor and enforce laws against illegal harvesting, intercepting a single shipment does little. Importing countries – particularly the United States, European Union nations and <a href="http://indicators.chathamhouse.org/explore-the-data/china">China</a> - must also initiate actions that reduce illegal timber <a href="http://dx.doi.org/10.3390/f7090191">production</a>. And this is where social science can play a role.</p>
<h2>Learning from wildlife trafficking</h2>
<p>Timber trafficking has many <a href="https://www.unodc.org/toc/en/crimes/environmental-crime.html">parallels</a> with illegal trade in charismatic and endangered wildlife, such as <a href="https://www.iucn.org/es/node/28733">pangolins</a>, <a href="https://theconversation.com/the-illegal-turtle-trade-why-i-keep-secrets-85805">turtles</a> and <a href="https://theconversation.com/to-reduce-rhino-poaching-take-demand-for-horns-seriously-34265">rhinos</a>. In both cases, the trade is extremely lucrative, and <a href="http://www.changewildlifeconsumers.org/">consumer demand</a> is a major driver of the black market.</p>
<p>To reduce demand, many countries use social science to stop consumers from purchasing illegal wildlife. <a href="https://www.researchgate.net/publication/273862857_Social_influence_approaches_to_encourage_resource_conservation_A_meta-analysis">Social influence</a> approaches attempt to convince us that peers are engaging in or refraining from certain actions, such as recycling or reusing grocery bags. They can also help convince organizations that certain actions are inappropriate and counter to rules and norms.</p>
<p>For example, advocates in China and Hong Kong have reduced pressure on endangered sharks by convincing elites and professionals through public awareness campaigns and political advocacy to eat less <a href="https://www.washingtonpost.com/world/in-china-victory-for-wildlife-conservation-as-citizens-persuaded-to-give-up-shark-fin-soup/2013/10/19/e8181326-3646-11e3-89db-8002ba99b894">shark fin soup</a>. And in Indonesia and Malaysia, Muslim clerics declared <a href="https://www.pri.org/stories/2016-01-05/islamic-clerics-declare-fatwa-poachers-indonesia-and-malaysia">fatwas</a> against wildlife poaching to signal social disapproval of it. Using the powerful medium of religion and their role as public leaders, clerics have aligned religious faithfulness with existing rules against poaching. In doing so, they make it easier to peer-pressure others and further stigmatize poaching and illegal purchasing.</p>
<h2>Steering consumer choices</h2>
<p>Governments and businesses can use similar strategies to address timber trafficking. They can educate consumers about the scale of the contraband trade and which <a href="http://www.wood-database.com/wood-articles/restricted-and-endangered-wood-species/">products</a> are likely to be illegally logged, much as ocean advocates are working to steer consumers away from buying <a href="http://www.latimes.com/food/dailydish/la-fo-sustainable-seafood-michael-cimarusti-20170526-htmlstory.html">fish that are overharvested</a>. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/216016/original/file-20180423-94149-1973m8e.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/216016/original/file-20180423-94149-1973m8e.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/216016/original/file-20180423-94149-1973m8e.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=464&fit=crop&dpr=1 600w, https://images.theconversation.com/files/216016/original/file-20180423-94149-1973m8e.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=464&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/216016/original/file-20180423-94149-1973m8e.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=464&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/216016/original/file-20180423-94149-1973m8e.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=583&fit=crop&dpr=1 754w, https://images.theconversation.com/files/216016/original/file-20180423-94149-1973m8e.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=583&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/216016/original/file-20180423-94149-1973m8e.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=583&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Pocket guide published by the Monterey Bay Aquarium to help consumers choose fish that are harvested sustainably.</span>
<span class="attribution"><a class="source" href="http://www.seafoodwatch.org/seafood-recommendations/consumer-guides">Monterey Bay Aquarium</a>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<p>Organizations exist to <a href="https://globaltimbertrackingnetwork.org/organisation/about/">track</a>, <a href="https://www.globalforestwatch.org/">monitor</a> and <a href="http://www.sfiprogram.org/about-us/sfi-strategic-vision/">certify</a> timber and timber products. But awareness is not enough. Stigmatizing or sanctioning the sale and purchase of illegal timber would be a useful further step. For example, governments could destroy shipments of confiscated timber in the same way that the United States and some African countries <a href="https://news.nationalgeographic.com/2017/08/wildlife-watch-ivory-crush-elephant-poaching/">burn or crush confiscated ivory</a> from slaughtered elephants. </p>
<p>Through events like <a href="https://www.arborday.org/">Arbor Day</a>, many Americans develop a generalized warm glow toward trees and forests. Portraying contraband wood products as harmful and damaging can help shape these views into more focused and sustained opposition to illegal timber trafficking.</p><img src="https://counter.theconversation.com/content/93115/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Kenneth E. Wallen 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>The illegal timber trade is a huge global business worth up to US$150 billion yearly. One way to curb it is by convincing consumers in wealthy countries that buying contraband wood products is wrong.Kenneth E. Wallen, Assistant Professor of Human Dimensions of Natural Resources, University of ArkansasLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/760292017-05-23T06:36:22Z2017-05-23T06:36:22ZWood beetles are nature’s recyclers – with a little help from fungi<figure><img src="https://images.theconversation.com/files/165334/original/image-20170413-25894-vg034a.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Larvae of longhorn beetle feeding on pine stump.</span> <span class="attribution"><span class="source">Michał Filipiak</span>, <span class="license">Author provided</span></span></figcaption></figure><p>Dead wood-eating beetles can cause damage to residential properties, just like termites may do. But they repay humans by performing a priceless service: helping us recycle decomposing dead trees. </p>
<p>Decomposition may have an unpleasant ring to it but it is a fundamental process in a functioning ecosystem, ensuring that we are not buried under the huge mass of dead organic matter that is produced every year right on our own doorsteps. </p>
<p>Dead wood-eating beetles are among the insect world’s best decomposers – organisms that digest dead matter and make their own living cells and tissues <a href="http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0115104">out of the acquired atoms</a>.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/165339/original/image-20170413-25894-1ulepbq.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/165339/original/image-20170413-25894-1ulepbq.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/165339/original/image-20170413-25894-1ulepbq.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/165339/original/image-20170413-25894-1ulepbq.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/165339/original/image-20170413-25894-1ulepbq.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/165339/original/image-20170413-25894-1ulepbq.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/165339/original/image-20170413-25894-1ulepbq.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">Huhu beetle (<em>Prionoplus reticularis</em>) larvae contribute to the decomposition of dead pine wood.</span>
<span class="attribution"><span class="source">Charlotte Simmonds/Wikimedia</span></span>
</figcaption>
</figure>
<p>The vast majority of organic matter produced worldwide every year is stored in wood, which is tough, and hard to digest and decompose. Worse yet, <a href="http://www.mdpi.com/2075-4450/7/2/13">wood is nutritionally stingy</a>. Dead wood is rich in sugars (cellulose, hemicelluloses and <a href="https://www.merriam-webster.com/dictionary/lignin">lignin</a>), but try surviving on sugar alone! </p>
<p>Digested wood may be source of energy, but it is insufficiently nutritious so that all the organisms developing in dead wood – beetles but also flies, moths, and bacteria – struggle with <a href="http://onlinelibrary.wiley.com/doi/10.1111/phen.12168/full">growth, development and maturation</a>.</p>
<p>Still, <a href="https://www.fs.usda.gov/treesearch-beta/pubs/11999">dead wood eaters</a> are able to survive and thrive on this low-quality food source. How they do it?</p>
<h2>Sugar-craving wood eaters</h2>
<p>All living organisms have their own ecosystems, with digestive tracts inhabited by symbionts, the scientific term for <a href="http://www.oxfordbibliographies.com/view/document/obo-9780199830060/obo-9780199830060-0006.xml?rskey=9xQ1Wi&result=1&q=symbiosis#firstMatch">organisms living in symbiosis</a>. </p>
<p><a href="http://what-when-how.com/insects/symbionts-aiding-digestion-insects/">Common knowledge would suggest that</a> the activity of wood-eating beetles’ symbionts provides them with nutritionally balanced diets. And we know that beetles are able to <a href="http://doi.wiley.com/10.1111/j.1365-2435.2008.01442.x">synthesise important organic compounds</a> out of nutrients furnished by their primary food, the dead wood. </p>
<p>But according to the <a href="https://www.nature.com/scitable/knowledge/library/the-conservation-of-mass-17395478">law of conservation of mass</a>, which dictates that the mass of the products in a chemical reaction must equal the mass of the reactants, a complete diet based on pure wood would be impossible. The atoms composing nutrients cannot be created out of nothing. </p>
<figure class="align-left zoomable">
<a href="https://images.theconversation.com/files/165342/original/image-20170413-10077-1dwx6n1.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/165342/original/image-20170413-10077-1dwx6n1.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/165342/original/image-20170413-10077-1dwx6n1.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=502&fit=crop&dpr=1 600w, https://images.theconversation.com/files/165342/original/image-20170413-10077-1dwx6n1.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=502&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/165342/original/image-20170413-10077-1dwx6n1.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=502&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/165342/original/image-20170413-10077-1dwx6n1.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=631&fit=crop&dpr=1 754w, https://images.theconversation.com/files/165342/original/image-20170413-10077-1dwx6n1.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=631&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/165342/original/image-20170413-10077-1dwx6n1.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=631&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Adult female wood-borer on a pine stump.</span>
<span class="attribution"><span class="source">Gailhampshire/Wikimedia</span></span>
</figcaption>
</figure>
<p>The problem is the organic composition of wood. Even if sugars (chemical structure CxH2yOy) are split into atoms, they are a source of only three chemical elements: <a href="https://www.nature.com/scitable/knowledge/library/biological-stoichiometry-102248897">carbon, hydrogen and oxygen</a>. This is not enough to live off even when we consider that sybionts have the ability to assimilate the fourth element, nitrogen, <a href="https://link.springer.com/article/10.1007%2FBF02181997">directly from the air</a>. </p>
<p><a href="http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0115104">It has been estimated</a> that for wood-eating beetles to consume the atomic composition of their bodies from wood alone would require approximately 40 years for males and 85 years for females, which are bigger. In fact, the beetle’s growth period spans at most three to four years in nature. </p>
<p>Beetles must therefore have a source of proper food, offering the needed atoms in the right proportions, and it cannot be the wood that seemingly comprises the whole of their diet. Where do they get the nutrients needed to grow and mature?</p>
<h2>Dead wood</h2>
<p>The answer is fungi.</p>
<p>During the first few years of decay after living wood dies, its <a href="http://www.mdpi.com/2075-4450/7/2/13">nutritional composition is changed by fungi</a>. Fungal tissues growing inside of dead wood are connected to nutritionally-rich areas of the environment outside of the wood. </p>
<p>These may consist of either <a href="http://www.asmscience.org/content/journal/microbiolspec/10.1128/microbiolspec.FUNK-0010-2016">protein-rich organic matter or of minerals and rocks</a>. Rocks may be disintegrated by fungi, and are sources of specific atoms utilised to build fungal tissues. Fungi may even “<a href="http://www.nature.com/doifinder/10.1038/35070643">predate</a>” on soil fauna. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/165331/original/image-20170413-11758-fclizj.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/165331/original/image-20170413-11758-fclizj.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/165331/original/image-20170413-11758-fclizj.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/165331/original/image-20170413-11758-fclizj.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/165331/original/image-20170413-11758-fclizj.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/165331/original/image-20170413-11758-fclizj.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/165331/original/image-20170413-11758-fclizj.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/165331/original/image-20170413-11758-fclizj.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">The larvae of the dead wood-eating longhorn beetle feeding on pine stump overgrown by fungi.</span>
<span class="attribution"><span class="source">Michał Filipiak</span></span>
</figcaption>
</figure>
<p>Acquired nutrients are translocated from the outside of dead wood to the inside via the fungal <a href="https://www.anbg.gov.au/fungi/mycelium.html">mycelium</a> (that is, mushroom “body”). By consuming decomposed wood that is rich in fungal tissues, the dead wood eater is able to grow, develop and reach maturity. </p>
<p>But even then its growth is constrained. <a href="http://onlinelibrary.wiley.com/doi/10.1111/phen.12168/full">To cope with the nutritional limitations</a> of dead wood, these beetles prolong their development, slowly growing over several years. During this time, they are able to gather all the necessary building blocks (atoms) for their adult bodies. </p>
<p>Their prolonged development time is made possible by the relative safety and climatic comfort of living inside logs and tree trunks, as opposed to in the outside world, which reduces mortality.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/165344/original/image-20170413-25882-zt4j9a.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/165344/original/image-20170413-25882-zt4j9a.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/165344/original/image-20170413-25882-zt4j9a.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=401&fit=crop&dpr=1 600w, https://images.theconversation.com/files/165344/original/image-20170413-25882-zt4j9a.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=401&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/165344/original/image-20170413-25882-zt4j9a.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=401&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/165344/original/image-20170413-25882-zt4j9a.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=504&fit=crop&dpr=1 754w, https://images.theconversation.com/files/165344/original/image-20170413-25882-zt4j9a.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=504&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/165344/original/image-20170413-25882-zt4j9a.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">Fungi may cover large areas and connect distant patches of the ecosystem, connected by its mycelium.</span>
<span class="attribution"><span class="source">James Lindsey/Wikipedia</span></span>
</figcaption>
</figure>
<h2>Ecological interactions</h2>
<p>Growth and development of dead-wood eating beetles are <a href="http://onlinelibrary.wiley.com/doi/10.1111/phen.12168/full">co-limited</a> by the scarcity of non-sugar nutrients rich in essential bioelements, such as nitrogen, phosphporous, potassium, sodium, magnesium, zinc and copper. Atoms of these elements have the nutrients used for building and maintaining the bodies of growing dead wood-eaters. </p>
<figure class="align-right ">
<img alt="" src="https://images.theconversation.com/files/165343/original/image-20170413-25875-1hihfge.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/165343/original/image-20170413-25875-1hihfge.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=900&fit=crop&dpr=1 600w, https://images.theconversation.com/files/165343/original/image-20170413-25875-1hihfge.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=900&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/165343/original/image-20170413-25875-1hihfge.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=900&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/165343/original/image-20170413-25875-1hihfge.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1131&fit=crop&dpr=1 754w, https://images.theconversation.com/files/165343/original/image-20170413-25875-1hihfge.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1131&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/165343/original/image-20170413-25875-1hihfge.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">
<figcaption>
<span class="caption">Borers like dark-colored (fungi-overgrown) wood.</span>
<span class="attribution"><span class="source">Svajcr/Wikimedia</span></span>
</figcaption>
</figure>
<p>Fungi utilise dead wood as a source of energy, and as they sprout all over logs during the first four or five years of decay, they nutritionally <a href="http://www.mdpi.com/2075-4450/7/2/13">enrich and rearrange</a> dead wood. In doing so, they create a nutritional niche for dead wood-eaters, allowing them to undergo <a href="http://onlinelibrary.wiley.com/doi/10.1111/phen.12168/full">growth and development to maturity</a>. </p>
<p>In turn, <a href="http://doi.wiley.com/10.1111/brv.12158">deadwood-eaters affect the wood</a>, fragmenting and shredding it and producing what’s known as <a href="http://doi.wiley.com/10.1002/ecs2.1300">frass</a> (wood pieces mixed with excrement that may be further decomposed by microorganisms). Beetles therefore contributing to further wood decomposition and nutrient cycling on the forest floor. </p>
<p>Thanks to complicated ecological interactions between dead wood, fungi and dead wood-eaters, the huge mass of the most common organic matter in land ecosystems is being continuously decomposed in forest ecosystems. It’s nature’s own recycling system.</p><img src="https://counter.theconversation.com/content/76029/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Michał Filipiak received funding from the Polish Ministry of Science and Higher Education (GrantNo.DS/WBiNoZ/INoŚ/DS761) and the National Science Centre, Poland (Grant No. DEC-2013/11/N/NZ8/00929). The funders had no role in decision to publish, or preparation of this text.
</span></em></p>It’s thanks to decomposition brought about by beetles and fungi that we’re not all buried under dead organic matter.Michał Filipiak, Environmental Biologist, Institute of Environmental Sciences, Jagiellonian UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/427602015-06-04T20:09:00Z2015-06-04T20:09:00ZWoodchips sound unsustainable, but they’re not as bad as you think<figure><img src="https://images.theconversation.com/files/83901/original/image-20150604-1009-g72fyw.jpg?ixlib=rb-1.1.0&rect=11%2C103%2C2537%2C1594&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Don't tread on woodchips.</span> <span class="attribution"><a class="source" href="http://commons.wikimedia.org/wiki/File%3AWoodchips_to_walk_on_(rkimpeljr)_001.jpg">Rick Kimpel/Wikimedia Commons</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span></figcaption></figure><p>One of the byproducts of the haggling over the new, scaled-back <a href="https://theconversation.com/au/topics/renewable-energy-target">Renewable Energy Target</a> is a renewed focus on woodchips, with the federal government’s <a href="http://www.comlaw.gov.au/Details/C2015B00071">draft legislation</a> seeking to include wood from native forests as a certified source of renewable energy. </p>
<p>Forests produce a wealth of goods and services, but some of these goods are now being labelled as <em>bad</em>. Opponents of issuing renewable energy certificates to woodchip burning, such as <a href="http://www.tai.org.au/system/files_force/Denniss%202015%20Do%20we%20need%20to%20burn%20forests%20to%20save%20the%20environment%20FINAL_0.pdf?download=1">The Australia Institute</a>, point out that fuel wood and woodchips expand the commercial pressure on forests, while directing investment away from competing renewable energy industries like wind and solar power. </p>
<p>There is also a visceral belief in some quarters that cutting down something as big as a tree to make a product as small as a woodchip cannot possibly be a smart strategy. But woodchip production isn’t all bad – they can be used to make a host of wood products that are greener than the alternatives, and can be harvested in ways that can actually benefit forests.</p>
<h2>Seeing the wood for the trees</h2>
<p>There is no doubt that selling woodchips into a local or global market would increase the commercial viability of forest operations. But forestry operations that produce sawlogs would not be the only enterprise that benefits. Fire hazard reduction operations could also become largely self-funding if the hazardous material could be sold as chip or fuel wood. </p>
<p>After several disastrous fire seasons, United States taxpayers are funding a <a href="http://www.abc.net.au/news/2015-04-10/bushfire-trials-prevention-clearing-forestry-fire/6383854">US$400 million hazard-reduction program</a> that uses tree removal as well as planned burning. Repurposing or selling the cleared material could recoup an estimated 40% of the cost of implementing the program.</p>
<p>Removing selected trees can have other benefits too. <a href="http://www.botany.unimelb.edu.au/vesk/EcothinPoster.pdf">Ecological thinning</a> - in which neighbouring trees are removed to help conserve selected tree species - can enhance the overall health of a forest and make it more resilient to drought and other stresses. Thinning will also promote growth on the remaining trees, allowing them to achieve more quickly the size needed to support <a href="https://theconversation.com/a-great-big-new-forest-park-wont-save-leadbeaters-possum-41237">hollows for arboreal mammals</a>. These operations are work-intensive and expensive, but again the costs could be offset by the sale of woodchips or fuel wood. </p>
<p>In Canada, the mountain pine beetle has <a href="https://www.nrcan.gc.ca/forests/insects-diseases/13381">devastated thousands of hectares of forest</a>. The Canadian government now provides substantial funding to First Nations, communities and school districts to help control this devastating outbreak by fuel management and hazard tree removal in areas that were previously infested. Much of the cost of these programs is recovered by selling the killed timber as solid, chip or fuel wood. </p>
<h2>The wood that could</h2>
<p>Forest goods can also be used to create building materials that can compete directly against steel or concrete. <a href="http://www.utsdesign.com/engineered_wood.asp">Engineered wood</a>, also called “composite” or “manufactured” wood, can be made from solid wood, woodchips, or even waste sawdust, and offers an alternative to raw timber products. </p>
<p>True, these products drive commercial forestry, just like traditional timber does. But full life-cycle analyses show that these solutions can be environmentally and economically <a href="http://www.sciencedirect.com/science/article/pii/S1462901101000442">more profitable than the steel and concrete alternatives</a>.</p>
<p>Similarly, fuel wood and other bioenergy products from forests can substitute for brown or black coal. Pelletised, gasified and liquified woodchips can be burned in the absence of wind or sunshine, with minimal net pollution, to produce heat for warming homes, generating steam for electricity production or even powering motor vehicles. Wood chips can even be made into flexible <a href="http://www.sciencedaily.com/releases/2015/05/150529083212.htm">high-capacity batteries</a> </p>
<p>In the past, one of the major problems with bioenergy was scale – plants needed to be large with extensive feed stock to be profitable. But improvements in technology mean the minimum size of efficient bioenergy plants has been <a href="http://www.sciencedirect.com/science/article/pii/S1359431108004766">substantially reduced</a>. Small industries can install gasifiers to meet their own energy requirements and potentially sell the excess power into the market. Similarly, mobile wood-chippers could follow thinning operations in a forest to supply small pelletising or liquefying plants. </p>
<p>Of course, electricity from biofuels competes directly with wind and solar power, as well as with coal-fired power, but there are numerous niches for alternatives to coal and oil. Wind farms, for instance, have an advantage in areas where there is no existing forest and where water-use policies restrict the establishment of new plantations.</p>
<h2>Hail the humble woodchip</h2>
<p>An individual woodchip looks too small to be really valuable. However, the structure and chemistry of that chip is truly remarkable, because it can be made into a wealth of products, from <a href="http://forestresearchllc.com/yahoo_site_admin/assets/docs/Potential_Markets_for_Chemicals_and_Pharmaceuticals_from_Woody_Biomass.8495603.pdf">pharmaceuticals</a> to <a href="http://www.architectureanddesign.com.au/news/world-s-tallest-timber-building-tops-out-in-melbou">skyscrapers</a>! These chips contain complex long molecules, rich with oxygen which form sugars and starches. These, in turn, can be made into glues, alcohols, solvents, and a host of drugs, polymers and dyes. These can be reconfigured to produce everything from <a href="http://qz.com/331879/carlsberg-may-soon-be-serving-beer-in-cardboard-bottles">biodegradable bottles</a> and other packaging, to <a href="http://www.theregister.co.uk/2015/05/28/wooden_computer_chips_invented_er_really">computer chips</a>.</p>
<p>Indeed, arguably the most effective way of keep biomass burning out of the renewable energy market might be to find even higher-value uses for woodchips, and thus price them out of the energy sector (although that strategy would admittedly not do much to reduce commercial uses of forests).</p>
<p>The biggest problem with woodchips is not their relative worthlessness, but the development of industries near the forest that can utilise its many strengths from energy production through to manufacturing. The challenge will be to make woodchip-based industries profitable at sizes that contribute sustainably to ecological thinning and fire-hazard reduction in our native forests, without damaging the rural landscape. </p>
<p>That way, the humble woodchip could deliver both industrial and environmental wins.</p><img src="https://counter.theconversation.com/content/42760/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Cris Brack regularly engages in consultancies for State and Commonwealth Government agencies on the methodologies and quality assurance of Regional Forest Agreements, forest inventory and management, Carbon Farming Initiatives and national carbon accounting. He is a member of the Institute of Foresters of Australia and a Senior Fellow in the Higher Education Academy.</span></em></p>The outcry over the government’s plan to allow wood burning from native forests under the revamped Renewable Energy Target belies the fact that woodchips can be useful and sustainable if harvested responsibly.Cris Brack, Assoc Professor Forest measurement & management, Australian National UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/256942014-06-19T05:01:57Z2014-06-19T05:01:57ZSwap steel, concrete, and brick for wood – wooden buildings are cheaper and cleaner<p>Although it may seem counter-intuitive, it would be better if we built buildings from wood than from concrete, brick, aluminium and steel. </p>
<p>We use millions of tonnes of these modern materials every year. They have many valuable properties, but are energy-intensive to create, accounting for around 16% of the entire planets’ fossil fuel production. Instead we could be using wood, which is also strong, renewable, and plentiful – we use only a fraction of the world’s available forestry resources. </p>
<p>Our <a href="http://www.tandfonline.com/doi/pdf/10.1080/10549811.2013.839386">research</a>, published in the Journal of Sustainable Forestry, estimated that the world’s forest contain about 385 billion cubic metres of wood, with an additional 17 billion cubic metres growing each year. A mere 3.4 billion cubic metres is harvested each year, mostly for subsistence fuel burning; the rest rots, burns in fires, or adds to forests’ density.</p>
<p>Swapping steel, concrete, or brick for wood and specially engineered wood equivalents would drastically reduce global carbon dioxide emissions, fossil fuel consumption and would represent a renewable resource. What’s more, managed properly this can be done without loss of biodiversity or carbon storage capacity.</p>
<h2>Wooden approach</h2>
<p>In our study undertaken by scientists from the <a href="http://environment.yale.edu">Yale School of Forestry & Environmental Studies</a> and the University of Washington’s <a href="http://coenv.washington.edu/">College of the Environment</a> we evaluated various scenarios including leaving forests untouched, burning wood for energy and use of wood as a construction material.</p>
<p>The 3.4 billion cubic meters of wood harvested each year accounts for only 20% of new annual growth. Increasing the wood harvest to 34% or more would have several profound and positive effects. Emissions amounting to 14-31% of global CO<sub>2</sub> would be avoided by creating less steel and concrete, and by storing CO<sub>2</sub> in the cell structure of wood products. A further 12-19% of annual global fossil fuel consumption would be saved, including savings from burning scrap wood and unsellable materials for energy.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/47177/original/wzpqkygq-1398704385.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/47177/original/wzpqkygq-1398704385.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/47177/original/wzpqkygq-1398704385.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=478&fit=crop&dpr=1 600w, https://images.theconversation.com/files/47177/original/wzpqkygq-1398704385.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=478&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/47177/original/wzpqkygq-1398704385.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=478&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/47177/original/wzpqkygq-1398704385.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=601&fit=crop&dpr=1 754w, https://images.theconversation.com/files/47177/original/wzpqkygq-1398704385.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=601&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/47177/original/wzpqkygq-1398704385.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=601&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">CO2 savings from using engineered Wood I-beams, Wood Beams, Wood Ply, Wood Sheathing, Ply Covering, and Wood Studs vs equivalent Steel Beams, Concrete Slabs, Steel Studs, and Stucco.</span>
<span class="attribution"><span class="source">Chad Oliver et. al/JSF</span></span>
</figcaption>
</figure>
<p>Building with wood consumes much less energy than using concrete or steel. For example, a wooden floor beam requires 80 megajoules (mj) of energy per square metre of floor space and emits 4kg CO<sub>2</sub>. By comparison, a square metre of floor space supported by a steel beam requires 516 mj and emits 40 kg of CO<sub>2</sub>, and a concrete slab floor requires 290 mj and emits 27kg of CO<sub>2</sub>.</p>
<p>By using efficient harvesting and production techniques, more CO<sub>2</sub> is saved through the avoided emissions, materials, and wood energy than is lost from the harvested forest – yet another reason to appreciate forests, and to protect them from endless deforestation for agriculture. Clearing trees for harvest is temporary, but converting forests to farmland is a permanent loss of all forest’s resources and biodiversity.</p>
<h2>Wooden materials</h2>
<p>If transport and assembly is taken into account, the 16% of global fossil fuels used to manufacture steel, concrete and brick is closer to 20-30%. These potential fuel and carbon emissions savings, already substantial, will become increasingly critical as demand for new buildings, bridges and other infrastructure surges with economic development in Asia, Africa and South America. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/47178/original/5frp5y4g-1398705077.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/47178/original/5frp5y4g-1398705077.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/47178/original/5frp5y4g-1398705077.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=470&fit=crop&dpr=1 600w, https://images.theconversation.com/files/47178/original/5frp5y4g-1398705077.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=470&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/47178/original/5frp5y4g-1398705077.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=470&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/47178/original/5frp5y4g-1398705077.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=590&fit=crop&dpr=1 754w, https://images.theconversation.com/files/47178/original/5frp5y4g-1398705077.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=590&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/47178/original/5frp5y4g-1398705077.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=590&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Wood construction for bridges in Quebec (A, photo Jean-Marc Dubois), Stadthaus in London (B, photo Will Pryce), aircraft hanger in Montreal, Quebec (C), and 20-storey wooden building (photo by Michael Green Architecture).</span>
<span class="attribution"><span class="source">Jean-Marc Dubois/Will Pryce/Michael Green Architecture</span></span>
</figcaption>
</figure>
<p>At the same time, new construction techniques have made wood even more effective as a building material for anything from <a href="http://www.popsci.com/article/technology/worlds-most-advanced-building-material-wood-0">bridges to mid-rise apartment buildings</a>. The <a href="http://www.naturallywood.com/emerging-trends/cross-laminated-timber-clt">cross-laminated timber</a> increasingly used in new buildings, made from alternating layers of perpendicular, wood pieces has strength approaching that of steel. </p>
<p>In 2009 a nine-storey building, <a href="http://www.klhuk.com/portfolio/residential/stadthaus,-murray-grove.aspx">Stadthaus</a>, in London, was built with CLT instead of steel construction and in <a href="http://www.archdaily.com/387769/wooden-skyscraper-berg-c-f-moller-architects/">Stockholm</a> a 34-storey wooden building has been given planning permission. There are many others, already built and in the pipeline.</p>
<p>Harvesting also reduces a forest’s likelihood of suffering a catastrophic wildfire, and improves its ability to withstand it. Maintaining a mix of forest habitats and tree densities in non-reserved forests would help preserve the varied biodiversity in ecosystems worldwide. Harvesting wood will save fossil fuel and CO<sub>2</sub>, and provide jobs – giving local people more reason to ensure the forests’ survival.</p><img src="https://counter.theconversation.com/content/25694/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Chad Oliver has minor ownership (5%) in a forest inventory company, SilviaTerra. In the past, he has consulted for the forest industry, the U.S.Forest Service, the United Nations, and other public and private organizations in his scientific capacity as an academician. </span></em></p>Although it may seem counter-intuitive, it would be better if we built buildings from wood than from concrete, brick, aluminium and steel. We use millions of tonnes of these modern materials every year…Chad Oliver, Pinchot Professor of Forestry and Environmental Studies, Director of Global Institute of Sustainable Forestry, Yale UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/78112012-07-29T20:47:15Z2012-07-29T20:47:15ZCan forest conservation and logging be reconciled?<figure><img src="https://images.theconversation.com/files/12732/original/w7g3d44p-1341815510.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">No simple matter: logging and conservation are not polar opposites, and controlled harvesting can fund the protection of forests.</span> <span class="attribution"><span class="source">AAP/Greenpeace/Jeremy Sutton-Hibbert</span></span></figcaption></figure><p>Is there a role for logging in ensuring the future of the world’s tropical forests and their rich diversity of plants and animals? For many this idea is absurd, because timber production achieving conservation goals have long been viewed as incompatible opposites. “Loggers” were tarred as planet plunderers, “greenies” were branded ignorant idealists, while researchers found themselves caught between warring factions with little interest in data from outside their own views and experiences. Sadly, this myopic and highly polarised view of preservation versus production rarely helps save vulnerable landscapes. Fortunately these views are changing.</p>
<p>Finding outcomes that offer real improvements for conservation gains depend on recognising some myths and acknowledging the dynamic nature of forests. Many people, especially in Australia, generally imagine all “logging” as broad-scale clear-felling. However, timber harvesting takes many forms, and large-scale clear-felling is at one end of a broad spectrum. In well-managed forests, foresters seek to harvest in an ecologically-appropriate way. Generally, clear-felling is appropriate only in forests that are naturally adapted to major disturbances (such as Australia’s wildfires). At the other end of the harvesting spectrum, single-tree selection is appropriate in forests that evolved with small-scale disturbance (such as many species-rich where most trees die standing and finally collapse from decay), and where seedlings tolerate heavy shade.</p>
<p>In most tropical forests managed for sustainable timber production, harvesting is selective. Between two and 20 stems are removed from each hectare of forest, once every few decades. When done carefully this leaves over 90% of the trees in place. Thus a logged, rich, tropical forest is still a rich tropical forest and stems regrow to replace those removed.</p>
<p>Many of the technical arguments against timber production in tropical rainforests relate to species loss or to the increased likelihood of forest conversion (i.e. that the forest will then be converted to some other non-forest use). There is ample evidence from various sites that logged forests lack many of the species - especially the larger animal species - found in more pristine forests. There are also many cases where forests that have been selectively logged for timber have subsequently been converted to pasture, oil palm, or other intensive uses. But, we now realise, the implied cause-and-effect relationships are not necessarily inevitable. Let’s deal with these issues one at a time.</p>
<figure class="align-left zoomable">
<a href="https://images.theconversation.com/files/12737/original/sz8twsfq-1341819261.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/12737/original/sz8twsfq-1341819261.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/12737/original/sz8twsfq-1341819261.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=904&fit=crop&dpr=1 600w, https://images.theconversation.com/files/12737/original/sz8twsfq-1341819261.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=904&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/12737/original/sz8twsfq-1341819261.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=904&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/12737/original/sz8twsfq-1341819261.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1135&fit=crop&dpr=1 754w, https://images.theconversation.com/files/12737/original/sz8twsfq-1341819261.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1135&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/12737/original/sz8twsfq-1341819261.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1135&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Passions run deep where the trees climb high.</span>
<span class="attribution"><span class="source">Flickr/Rainforest Action Network</span></span>
</figcaption>
</figure>
<p>First, how does timber harvest affect the biological value of tropical forests? <a href="http://jkv.50megs.com/ConsLet.pdf">Our recent study</a> summarised over 100 scientific papers from a range of sites and concluded that 85% to 100% of the forest biodiversity was maintained in forests that have been logged once. Other studies of forests harvested repeatedly have found similar results. This doesn’t mean that other older observations were wrong – just that they didn’t distinguish the cause of the species declines they observed. Areas that are accessible for timber harvest are often accessible for hunting, pet-trade collecting, gold panning, and so on. Certainly, new logging roads often provide access into once inaccessible areas, and can exacerbate and facilitate other harmful activities, but whether they are the cause is a matter of semantics. High levels of hunting can and do occur in strictly protected forests, too – but no-one would argue that that is a valid reason not to have strictly protected forests. In both cases, logged or protected forests, the answer is the same – stronger incentives and controls are required to favour the desired conservation outcome.</p>
<p>The question then is how to provide these incentives and controls. On the ground, control of activities like hunting is often more practical in actively-managed production forest than in national parks starved of staff and resources. The need to control, and in some cases prohibit, hunting is now a common element of good practice in forest management and is implemented in many concessions (in Sarawak, Congo, and other concessions accredited by the <a href="http://www.fsc.org/">Forest Stewardship Council</a>).</p>
<p>Secondly, what are the implications of a timber harvest for sustainable forest cover? Experience shows that logged forests have at different times, been cleared, maintained for subsequent harvests, and elevated to national parks. Clearly the fate of a logged forest depends on many things, including the external pressures on land and the degree to which we are willing and able to value and protect both logged and unlogged forests. But studies of concessions in several parts of the world where law enforcement in protected areas is weak reveal instructive cases where logged forests <a href="http://www.cifor.org/online-library/browse/view-publication/publication/1663.html">have been found to resist conversion</a> better than unlogged forests (e.g. in Sumatra and Borneo). These cases, as with the elimination of hunting mentioned in the previous example, show the potential benefits of having local caretakers with the ability, motivation, and support to support forest conservation.</p>
<p>The chief question is how to achieve the best results. Even if we forget the demand for timber and consider only conservation benefits, and draw on the examples given above, it is apparent that logged forests bring options and opportunities.</p>
<p>No-one suggests that all forests should be logged. As far as we are aware everyone agrees that some forests should be set aside and protected. Ideally these areas should be as big and as well-connected as we can manage. Low-density, wide-ranging forest-dependent species such as Borneo’s clouded leopards will depend on these large areas. But, given other demands on land and resources, such strictly protected areas are unlikely to ever make up more than a minority of the landscape.</p>
<p>This appears especially true in poorer regions of the world where people live on the land and there are massive pressures to generate the funds they need for development from high value crops like soya and oil palm. In such regions we are unlikely to find the money necessary to protect and manage large reserved areas and meet the aspirations of the people. However, timber production provides one way in which forest lands can provide income and employment while retaining forest: in simple terms, the forest can pay for its own protection.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/12734/original/pb62tjqf-1341815826.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/12734/original/pb62tjqf-1341815826.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/12734/original/pb62tjqf-1341815826.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/12734/original/pb62tjqf-1341815826.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/12734/original/pb62tjqf-1341815826.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/12734/original/pb62tjqf-1341815826.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/12734/original/pb62tjqf-1341815826.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">
<figcaption>
<span class="caption">Light touch: a Papuan hunts in forests where his clan selectively fells trees.</span>
<span class="attribution"><span class="source">AAP/Greenpeace/Natalie Behring</span></span>
</figcaption>
</figure>
<p>From a non-negotiable starting point with islands of strictly-protected forests, we can choose the fate of the rest of the landscape: we can strive for a landscape dominated by non-forests (e.g., agriculture) with little connecting forest, or we can seek to maintain productive working forests that provide valuable habitats for most forest species, provide connectivity among populations, and allow the landscape to sustain many wide-ranging forest species.</p>
<p>Even better, these forests can be supervised and managed by people who care about them and can combat alien species, check fires, and confront hunters and other threats. While there are risks, many researchers believe that this latter option comprising a matrix of managed production-forest remains one way to ensure the survival of the world’s tropical forests and their rich diversity. Conservation is seldom simple to achieve and there will be challenges. Nonetheless, in our view well managed production forestry, as part of a larger forest-landscape guided by science, offers a vision where once conflicting interests will benefit by working together.</p>
<p><em>Comments welcome below.</em></p><img src="https://counter.theconversation.com/content/7811/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>From time to time, Jerry Vanclay offers advice to governments, companies and other agencies about sustainable harvesting of forests, and in some cases, receives payment for this advice.</span></em></p><p class="fine-print"><em><span>Douglas Sheil has conducted and managed various research projects on the impacts of tropical forest management on biodiversity and on local people. Most has been funded through CIFOR, by the EC, ITTO, WB and other major donors. He does not receive financial support from any timber producing agencies.</span></em></p>Is there a role for logging in ensuring the future of the world’s tropical forests and their rich diversity of plants and animals? For many this idea is absurd, because timber production achieving conservation…Jerry Vanclay, Dean of Science, Southern Cross UniversityDouglas Sheil, Director of the Institute of Tropical Forest Conservation, Institute of Tropical Forest ConservationLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/36862011-10-06T19:45:38Z2011-10-06T19:45:38ZExplainer: is recycled paper really better for the environment?<figure><img src="https://images.theconversation.com/files/4192/original/turkeychik.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Buying this will make you feel good, but should it?</span> <span class="attribution"><span class="source">turkeychik</span></span></figcaption></figure><p>For many years, individual consumers, industries and governments have all purchased printing and writing paper made with a high recycled-fibre content.</p>
<p>Why? Because they believe it is the most responsible and environmentally friendly thing to do. But is it really better for the environment?</p>
<p>Traditionally, fibre for paper and paper packaging comes from the wood of trees, with other sources of fibre – such as sugarcane and straw – making a minor contribution.</p>
<p>In more recent times, waste paper has also been used as a source of fibres. These recycled fibres are processed to make paper products similar to those made from original (virgin) wood fibres.</p>
<p>Paper used in stationery products is often a blend of virgin and recycled fibres. This is to maintain the brightness of the paper – virgin fibres produce whiter paper – while minimising environmental impacts. Manufacturers also tend to “remix” the blend depending on whether there is more recycled or virgin fibre available.</p>
<p>Products made from 100% recycled content are usually of a lower quality than those from virgin fibres. But 100% recycled products are still very suitable for most stationery applications.</p>
<h2>White paper in; white paper out</h2>
<p>Recycled paper is now everywhere in our lives. But recycling paper and then reusing the fibres is not always as simple as it might seem.</p>
<figure class="align-left ">
<img alt="" src="https://images.theconversation.com/files/4134/original/dwwebber.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/4134/original/dwwebber.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/4134/original/dwwebber.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/4134/original/dwwebber.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/4134/original/dwwebber.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/4134/original/dwwebber.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/4134/original/dwwebber.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">There are real benefits in paper recycling.</span>
<span class="attribution"><span class="source">dwwebber</span></span>
</figcaption>
</figure>
<p>To manufacture recycled paper, the source paper needs to be white and similar in composition to what the recycled paper will be used for. For instance, if you’re going to make recycled paper for use in office photocopiers, you’ll need waste office paper to begin with.</p>
<p>Daily newspapers and weekly magazines are usually not suitable. Although they are white, their “whiteness” is often from clay powder coating, and the fibres themselves discolour readily.</p>
<p>(Newspapers are generally recycled to make newspapers. Cardboard is usually recycled into other “brown” products, including paper bags and corrugated cardboard.)</p>
<h2>Where does the fibre come from?</h2>
<p>To make recycled paper that is good enough to meet consumer demand, manufacturers have to collect and sort enough high-quality white paper. </p>
<p>In relatively low-population-density countries such as Australia this can be a costly exercise. (Driving bundles of waste paper between cities is expensive in a country this big).</p>
<p>But when the international price of virgin white fibre goes up – making non-recycled paper prohibitively expensive – it becomes more attractive to pay for the local collection and processing of waste white paper into recycled white fibre.</p>
<p>When you head to your local stationery store, the products you see on the shelves are made from both imported – usually from south-east Asia, east Asia or the Americas – and locally-made paper.</p>
<figure class="align-right ">
<img alt="" src="https://images.theconversation.com/files/4135/original/hannanik.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/4135/original/hannanik.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=800&fit=crop&dpr=1 600w, https://images.theconversation.com/files/4135/original/hannanik.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=800&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/4135/original/hannanik.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=800&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/4135/original/hannanik.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1005&fit=crop&dpr=1 754w, https://images.theconversation.com/files/4135/original/hannanik.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1005&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/4135/original/hannanik.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">Virgin fibres often come from plantation forests.</span>
<span class="attribution"><span class="source">hannanik</span></span>
</figcaption>
</figure>
<p>These products may be marketed as having various levels of recycled fibre content up to 100%. Any virgin fibre content is usually labelled as coming from certified, sustainable wood sources – selected native forests and plantations – rather than from tropical rainforests or old growth native forests.</p>
<p>This is because consumers are now demanding more sustainable, certified papers, and tend to avoid papers from old-growth forests.</p>
<p>(Certification of a paper’s origin is done by an independent authority such as the <a href="http://www.fscaustralia.org/">Forest Stewardship Council</a> (FSC)). </p>
<p>Product and brand credibility would be at risk if a supplier chose to make incorrect claims about the paper they sold.</p>
<p>But of course, not all claims are entirely watertight. For example, tropical rainforest tree species have recently been <a href="http://www.theage.com.au/environment/kmart-envelopes-fail-rainforest-test-20110925-1krs8.html">identified in stationery papers</a> imported into Australia. </p>
<p>But the provenance of paper is difficult for consumers to independently confirm, and can be difficult to prove even by experts with specialist laboratory analysis of the paper. </p>
<h2>Better for the environment?</h2>
<p>From an environmental-impact point of view, using products made from recycled fibre or virgin fibre is not an either/or proposition.</p>
<p>It makes sense to recycle paper (and use recycled-paper products) where possible, even though there are some environmental penalties involved in the production of recycled paper. These penalties can include the use of transport fuel used in the collection and transport of paper over long distances.</p>
<figure class="align-left ">
<img alt="" src="https://images.theconversation.com/files/4132/original/AFP_PHOTO_Richard_A._BROOKS.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/4132/original/AFP_PHOTO_Richard_A._BROOKS.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=417&fit=crop&dpr=1 600w, https://images.theconversation.com/files/4132/original/AFP_PHOTO_Richard_A._BROOKS.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=417&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/4132/original/AFP_PHOTO_Richard_A._BROOKS.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=417&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/4132/original/AFP_PHOTO_Richard_A._BROOKS.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=524&fit=crop&dpr=1 754w, https://images.theconversation.com/files/4132/original/AFP_PHOTO_Richard_A._BROOKS.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=524&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/4132/original/AFP_PHOTO_Richard_A._BROOKS.jpg?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">There are significant costs involved in collecting paper for recycling.</span>
<span class="attribution"><span class="source">AFP/Richard A. Brooks</span></span>
</figcaption>
</figure>
<p>Also, we can’t keep recycling the paper we have now forever. Virgin fibres have to be introduced into the process at some point.</p>
<p>On average, a fibre can be recycled seven times before it is too degraded to make paper. Because of this fact, there has to be a supply of virgin wood fibres to maintain the supply and quality of fibres and, therefore, the paper. </p>
<p>Fortunately, the modern processes for extracting virgin fibres are biomass energy self-sufficient. When making stationary paper, the natural adhesive which binds the wood together (<a href="http://www.ili-lignin.com/aboutlignin.php">lignin</a>) is dissolved from the wood then burnt to power the process. Any shortage in necessary energy can be generated by burning forestry waste such as tree bark.</p>
<p>These processes have minimal environmental impact, provided renewable and certified wood sources are used. </p>
<p>Stationery papers are only a part of the paper and paper packaging industry, but consumers can choose to buy quality goods with recycled fibre content, according to their preference for quality, environmental impact and cost.</p>
<p>Consumers should be aware that recycled paper can, but not always, have an environmental advantage and that they may be charged more for the privilege. The best protection is to buy paper produced entirely in Australia.</p>
<p><em>This article was written with the assistance of Dr Bruce Allender, Microscopist & Environmental Specialist at Covey Consulting.</em></p><img src="https://counter.theconversation.com/content/3686/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Tom Rainey 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>For many years, individual consumers, industries and governments have all purchased printing and writing paper made with a high recycled-fibre content. Why? Because they believe it is the most responsible…Tom Rainey, Research Fellow, Queensland University of TechnologyLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/32352011-09-11T20:10:18Z2011-09-11T20:10:18ZFirewood and biodiversity - are we burning their homes to warm ours?<figure><img src="https://images.theconversation.com/files/3468/original/open_fire_sediger.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Cosy, sure, unless your house is on fire.</span> <span class="attribution"><span class="source">sediger/Flickr</span></span></figcaption></figure><p>The issue of firewood management has recently attracted <a href="http://www.theage.com.au/victoria/firewood-fee-given-the-chop-20110831-1jm2i.html">renewed attention</a> in Victoria, where the State Government has <a href="http://www.dse.vic.gov.au/forests/firewood">changed the regulations</a> on collecting firewood from State Forests. Firewood is cheap fuel for households, but it is also vital habitat for many species. The new regulations may put these species at threat. </p>
<h2>New regulations make firewood collection easier</h2>
<p>From September 1, 2011, individuals no longer need a permit to collect firewood for personal use. Some 90 sites across the state are designated as <a href="http://www.dse.vic.gov.au/forests/firewood/collection-areas">firewood collection areas</a>.</p>
<p>Many Victorians, particularly in rural areas, rely heavily on firewood as a low-cost source of heating. Firewood collecting is often a family-oriented activity. Some see it as keeping the forest “tidy” while others (mistakenly) believe they are reducing the fire risk. So why should we be concerned?</p>
<p>In our native forests, fallen wood (“coarse woody debris”) and standing live and dead trees provide habitat for many native plant and animal species. </p>
<p>When people harvest firewood by cutting down trees or collecting woody debris, they directly (through resource removal) and indirectly (by habitat alteration) affect biodiversity. </p>
<h2>Dead wood - it’s home to animals and food for forests</h2>
<p>There are many invertebrate species that specialise in exploiting dead wood, and depend on this wood for their survival. Many of these organisms are part of co-adapted systems with fungi and plants, or they form part of complex food webs. Declines in one group can have indirect impacts on a range of other species and ecosystem processes. </p>
<p>The breakdown (decomposition) of dead wood is an essential process in the recycling of forest nutrients. It slowly releases essential mineral nutrients back to the soil.</p>
<p>A number of small mammal species rely on fallen wood for shelter, with the associated cracks and crevices and adjacent leaf litter providing a rich source of insect food. </p>
<p>Fallen wood provides shelter and basking sites for snakes and lizards and refuge sites for frogs. </p>
<p>There is mounting evidence that nearly 20 species of birds in Victoria are declining due to the effects of firewood removal. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/3467/original/bushstone_curlew_JJ_Harrison.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/3467/original/bushstone_curlew_JJ_Harrison.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=600&fit=crop&dpr=1 600w, https://images.theconversation.com/files/3467/original/bushstone_curlew_JJ_Harrison.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=600&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/3467/original/bushstone_curlew_JJ_Harrison.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=600&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/3467/original/bushstone_curlew_JJ_Harrison.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=754&fit=crop&dpr=1 754w, https://images.theconversation.com/files/3467/original/bushstone_curlew_JJ_Harrison.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=754&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/3467/original/bushstone_curlew_JJ_Harrison.jpg?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">The endangered bush-stone curlew relies on fallen wood.</span>
<span class="attribution"><span class="source">JJ Harrison</span></span>
</figcaption>
</figure>
<p>In our fire-prone forests, fallen wood often provides protection during fire; a temporary home from which animals can recolonise the regenerating forest. </p>
<p>Plant communities are also impacted by firewood collection. Direct impacts (including weed invasion) arise due to soil disturbance, while indirect effects on ecosystem function are likely through interruptions to nutrient cycling.</p>
<h2>We know wood matters, so why are we treating it as free fuel?</h2>
<p>The significance of these issues is well recognised. Under Victoria’s <a href="http://www.austlii.edu.au/au/legis/vic/consol_act/fafga1988205/">Flora and Fauna Guarantee (FFG) Act 1988</a>, “loss of coarse woody debris from Victorian native forests and woodlands” is listed as a “Potentially Threatening Process”. There are at least 17 animal species listed under the FFG Act which are threatened by firewood collection from native forests and woodlands.</p>
<p>So, if we acknowledge the ecological significance of fallen wood, why do we continue to allow its removal from our native forests? </p>
<p>Some say the impact is small and localised. In Victoria, about 14% of firewood used for domestic purposes is collected (legally) from State Forest. Rates of illegal collection, though, are thought to be considerable. </p>
<p>Firewood collectors may only collect fallen wood and must leave logs with hollows and logs growing moss and fungi. Over the long term, illegal removal of live and dead trees and the repeated legal removal of undecayed fallen material means there will be no more old fallen logs. This is bad news for habitat and for nutrient cycling.</p>
<h2>Without permits, we won’t know when ecosystems are in trouble</h2>
<p>Has the government sent the wrong message to the community? Anecdotal evidence suggests there is considerable confusion about these recent changes to regulations. A number of callers to ABC radio thought they could now collect freely from any area of State Forest and public roadsides.</p>
<p>By abandoning the permit system, the <a href="http://www.dse.vic.gov.au/">Department of Sustainability and Environment</a> can no longer monitor the impact of firewood removal on biodiversity and associated ecosystem processes. </p>
<p>The permit system was imprecise, but now there are no data being collected, which means no way to estimate sustainable yields of fallen timber. As existing collection areas are denuded of fallen wood, new areas will inevitably be identified. There will be serious localised depletion of this resource and subsequent flow-on effects; but we will hear no warning bells.</p>
<p>While our native forests may be promoted as a “cheap” (economic) source of firewood, it is time to fully appreciate the <a href="http://www.dse.vic.gov.au/__data/assets/pdf_file/0013/122206/Ecologicalimpactsoffirewoodcollection.pdf">environmental costs of this activity</a>. We must broaden the discussion to consider alternatives, such as the developing fuel-wood industry and community-based woodlots. There is definitely socio-economic value to firewood collection, but we must also acknowledge the environmental trade-offs.</p><img src="https://counter.theconversation.com/content/3235/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Alan York receives funding from the Victorian Department of Sustainability and Environment through a Research Agreement between DSE and the University of Melbourne.</span></em></p>The issue of firewood management has recently attracted renewed attention in Victoria, where the State Government has changed the regulations on collecting firewood from State Forests. Firewood is cheap…Alan York, Associate Professor, Department of Forest and Ecosystem Science, The University of MelbourneLicensed as Creative Commons – attribution, no derivatives.