tag:theconversation.com,2011:/au/topics/soil-carbon-6589/articlesSoil carbon – The Conversation2024-03-08T05:37:23Ztag:theconversation.com,2011:article/2243372024-03-08T05:37:23Z2024-03-08T05:37:23ZCultural burning is better for Australian soils than prescribed burning, or no burning at all<figure><img src="https://images.theconversation.com/files/580328/original/file-20240307-10578-g6monm.jpeg?ixlib=rb-1.1.0&rect=28%2C5%2C3805%2C2149&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">Ulladulla Local Aboriginal Land Council and Mane Collective</span></span></figcaption></figure><p>Imagine a landscape shaped by fire, not as a destructive force but as a life-giving tool. That’s the reality in Australia, where Indigenous communities have long understood the intricate relationship between fire, soil and life. <a href="https://onlinelibrary.wiley.com/doi/full/10.1111/emr.12592?saml_referrer">Cultural burning</a>
has been used for millennia to care for landscapes and nurture biodiversity. In contrast, government agencies conduct “<a href="https://knowledge.aidr.org.au/media/4893/overview-of-prescribed-burning-in-australasia.pdf">prescribed burning</a>” mainly to reduce fuel loads.</p>
<p>In <a href="https://www.mdpi.com/2571-6255/7/3/75">our new research</a>, we compared cultural burning to agency-led prescribed burning or no burning. We studied the effects on soil properties such as moisture content, density and nutrient levels.</p>
<p>Both fire treatments increased soil moisture and organic matter, while reducing soil density. That means burning improved soil health overall. But cultural burning was the best way to boost soil carbon and nitrogen while also reducing soil density, which improves the soil’s ability to nurture plants.</p>
<p>Understanding the effects of different fire management techniques is crucial for developing more sustainable land management practices. By studying what happens to the soil, we can work out how best to promote healthy, resilient ecosystems while also reducing risks of uncontrolled bushfires. </p>
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<figcaption><span class="caption">Cultural Burning for Resilience (2021), a mini documentary featuring coauthors Vic Channell, Leanne Brook and Katharine Haynes.</span></figcaption>
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Read more:
<a href="https://theconversation.com/before-the-colonists-came-we-burned-small-and-burned-often-to-avoid-big-fires-its-time-to-relearn-cultural-burning-201475">Before the colonists came, we burned small and burned often to avoid big fires. It's time to relearn cultural burning</a>
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<h2>The vital role of fire</h2>
<p>Fire has shaped Australian landscapes for millions of years, transforming ecosystems and influencing biodiversity.</p>
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<a href="https://images.theconversation.com/files/580338/original/file-20240307-22-oaacq9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="People standing around a slow-burning patch of bracken" src="https://images.theconversation.com/files/580338/original/file-20240307-22-oaacq9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/580338/original/file-20240307-22-oaacq9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=800&fit=crop&dpr=1 600w, https://images.theconversation.com/files/580338/original/file-20240307-22-oaacq9.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=800&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/580338/original/file-20240307-22-oaacq9.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=800&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/580338/original/file-20240307-22-oaacq9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1005&fit=crop&dpr=1 754w, https://images.theconversation.com/files/580338/original/file-20240307-22-oaacq9.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1005&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/580338/original/file-20240307-22-oaacq9.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1005&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
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<span class="caption">Slow, cool burns are safe for onlookers.</span>
<span class="attribution"><span class="source">Ulladulla Local Aboriginal Land Council</span></span>
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<p>For Indigenous Australians, fire is not just a tool but a way of life. Fire is used to care for Country, for cultural purposes including ceremonies, to promote new plant growth and food resources, and to facilitate hunting and gathering. </p>
<p>Cultural burning is only ever conducted when it will benefit the health of Country. It is a practice deeply rooted in Indigenous knowledge and traditions. Fires are small, slow and cool. Practitioners read signs in the environment in relation to the local flora and fauna that provide guidance on the right time to burn. </p>
<p>In comparison, prescribed burning, conducted by government agencies, is principally conducted to reduce fuel loads and minimise the risk of wildfires. Fires are often larger and burn hotter than cultural burning. </p>
<p>In recent times, bushfires have become <a href="https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0242484">more frequent and severe</a> in parts of Australia. So understanding and <a href="https://www.publish.csiro.au/wf/pdf/WFv29n11_BR">supporting Indigenous-led fire management practices</a> is becoming increasingly important for sustainable land management. </p>
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Read more:
<a href="https://theconversation.com/how-1970s-conservation-laws-turned-this-paradise-on-earth-into-a-tinderbox-192401">How 1970s conservation laws turned this ‘paradise on Earth’ into a tinderbox</a>
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<h2>Unlocking the secrets of soil health</h2>
<p>Our new research sheds light on the impact of fire management techniques on soil properties. The study was conducted on the south coast of New South Wales, on land managed by the Ulladulla Local Aboriginal Land Council. At this plot, one area of land experienced no burn, another was burnt by NSW Rural Fire Service and another experienced a cultural burn. </p>
<p>While the area burnt was relatively small, about 5,000 square metres for each plot, it can still help shed a light on the effect of fire treatments on soil properties.</p>
<p>We found both agency-led prescribed burning and cultural burning increased soil moisture levels. There may be different reasons for this. For soils that experienced the cultural burn, the extra moisture could be explained by the reduction in soil density, which promotes water flow. For soils that experienced the agency-led prescribed burn, where density didn’t decrease much, it’s possible the hotter fire removed the water-repellant layer of soil that sometimes develops following a fire, allowing more moisture to soak in.</p>
<p>Cultural burning had a more pronounced effect on reducing soil density and increasing organic matter content. Having more organic matter in the soil means more nutrients such as carbon and nitrogen are available to plants. Lower density improves soil structure. Both improve the capacity of ecosystems to withstand environmental stress such as drought and wildfire. </p>
<p>These findings suggest cultural burning not only benefits soil health but also helps make ecosystems more resilient, by providing more water and nutrients that native plants need. </p>
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<a href="https://images.theconversation.com/files/580352/original/file-20240307-16-a0d19p.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Research student Jessica Davis measuring carbon dioxide emissions from soil" src="https://images.theconversation.com/files/580352/original/file-20240307-16-a0d19p.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/580352/original/file-20240307-16-a0d19p.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/580352/original/file-20240307-16-a0d19p.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/580352/original/file-20240307-16-a0d19p.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/580352/original/file-20240307-16-a0d19p.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/580352/original/file-20240307-16-a0d19p.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/580352/original/file-20240307-16-a0d19p.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>
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<span class="caption">Carbon dioxide emissions from soil can be measured in the field.</span>
<span class="attribution"><span class="source">Jessica Davis</span></span>
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<h2>Embracing Indigenous wisdom</h2>
<p>Indigenous communities use cultural land management practices, of which cultural burning is one tool, to care for Country as kin. They do not see themselves as separate to the environment. Instead their practices are guided by place-based knowledge that weaves human, spiritual and ecological needs together in a symbiotic relationship where one cannot thrive without the other. </p>
<p>Supporting Indigenous-led fire practices is not just about what it can do for the environment. It’s also a recognition of the deep cultural and spiritual connections Indigenous communities have with the land. </p>
<p>By learning from and working with Indigenous communities, we can foster a more harmonious relationship with Country, one that benefits both people and the environment.</p>
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<a href="https://images.theconversation.com/files/580335/original/file-20240307-24-m4ckp4.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A group of people standing in the bush during a controlled burn, with the sun in the background peeking through the smoke" src="https://images.theconversation.com/files/580335/original/file-20240307-24-m4ckp4.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/580335/original/file-20240307-24-m4ckp4.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=800&fit=crop&dpr=1 600w, https://images.theconversation.com/files/580335/original/file-20240307-24-m4ckp4.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=800&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/580335/original/file-20240307-24-m4ckp4.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=800&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/580335/original/file-20240307-24-m4ckp4.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1005&fit=crop&dpr=1 754w, https://images.theconversation.com/files/580335/original/file-20240307-24-m4ckp4.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1005&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/580335/original/file-20240307-24-m4ckp4.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1005&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
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<span class="caption">Cultural burning is a team effort.</span>
<span class="attribution"><span class="source">Ulladulla Local Aboriginal Land Council</span></span>
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<h2>Rekindling our relationships</h2>
<p>Indigenous fire management practices offer invaluable wisdom and the potential to transform our approach to land stewardship. </p>
<p>By embracing these practices, we can nurture healthier soils, promote biodiversity, and foster more resilient ecosystems. </p>
<p>Practically, to make this possible, ongoing investment is required to build the capacity of Indigenous communities to fulfil their obligations to care for Country. Policies must be updated to allow greater access to Country and to reduce red tape and bureaucracy.</p>
<p>There is a danger here. Government agencies often want to incorporate or take on some of the principles of cool burns themselves, forgetting the cultural aspects and the need for this to be Indigenous-led. We must understand this is not just about managing fires, it’s about rekindling our relationship with the land and learning from those who have lived in harmony with it for thousands of years. </p>
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Read more:
<a href="https://theconversation.com/new-research-in-arnhem-land-reveals-why-institutional-fire-management-is-inferior-to-cultural-burning-184562">New research in Arnhem Land reveals why institutional fire management is inferior to cultural burning</a>
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<img src="https://counter.theconversation.com/content/224337/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Anthony Dosseto receives funding from the Australian Research Council.</span></em></p><p class="fine-print"><em><span>Katharine Haynes, Leanne Brook, and Victor Channell 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>What does fire management do to soils? We compared prescribed burning to cultural burning and looked at how soil properties changed after fire. Cultural burning was better.Anthony Dosseto, Professor, University of WollongongKatharine Haynes, Honorary Senior Research Fellow, University of WollongongLeanne Brook, CEO, Ulladulla Local Aboriginal Land Council, Indigenous KnowledgeVictor Channell, Murramarang and Walbunga Elder, Indigenous KnowledgeLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2247452024-03-04T19:22:07Z2024-03-04T19:22:07ZIn a dangerously warming world, we must confront the grim reality of Australia’s bushfire emissions<p>In the four years since the Black Summer bushfires, Australia has become more focused on how best to prepare for, fight and recover from these traumatic events. But one issue has largely flown under the radar: how the emissions produced by bushfires are measured and reported. </p>
<p>Fires comprised 4.8% of <a href="https://www.iea.org/reports/global-energy-review-co2-emissions-in-2021-2">total global emissions in 2021</a>, producing about <a href="https://www.weforum.org/agenda/2021/12/siberia-america-wildfires-emissions-records-2021/">1.76 billion tonnes</a> of carbon dioxide (CO₂). This <a href="https://edgar.jrc.ec.europa.eu/report_2023?vis=co2tot#emissions_table">exceeds the emissions</a> of almost all individual countries except the biggest emitters of China, the United States, India and Russia.</p>
<p>It’s crucial to accurately track the greenhouse gas emissions bushfires produce. However, the modelling and reporting of bushfire emissions is a complex, poorly understood area of climate science and policy. </p>
<p>The University of Tasmania recently brought together leading scientists and policymakers to discuss Australia’s measuring and reporting of bushfire emissions. The resulting <a href="https://www.utas.edu.au/__data/assets/pdf_file/0009/1697841/Measuring-and-reporting-bushfire-emissions.pdf">report</a>, just released, shows where Australia must improve as we face a fiery future.</p>
<h2>Getting a read on bushfire emissions</h2>
<p>By the end of this century, the number of extreme fire events around the world is expected to increase by <a href="https://www.unep.org/news-and-stories/press-release/number-wildfires-rise-50-2100-and-governments-are-not-prepared">up to 50% a year</a> as a direct result of human-caused climate change.</p>
<p>Emissions from bushfires fuels global warming – which in turn makes bushfires even more destructive. Estimating these emissions is a complicated and technical task, but it is vital to understanding Australia’s carbon footprint.</p>
<p>Australia reports on emissions from bushfires according to rules defined by the United Nations Framework Convention on Climate Change (UNFCCC), and as part of our responsibilities under the <a href="https://unfccc.int/process-and-meetings/the-paris-agreement">Paris Agreement</a>.</p>
<p>Countries estimate bushfire emissions in different ways. Some rely on default data provided by the UNFCCC. In contrast, <a href="https://www.dcceew.gov.au/sites/default/files/documents/national-inventory-report-2021-volume-1.pdf">Australia’s modelling</a> combines the area of burned land with highly specific local data on the types of fuel burned (such as leaves, bark and dead wood) and the amount of <a href="https://research.csiro.au/pyropage/wp-content/uploads/sites/17/2017/04/CSIRO-PyroPage-Issue-10-GHG-Emissions.pdf">different types of gas</a> these fuels emit. This makes it among the most sophisticated approaches in the world.</p>
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Read more:
<a href="https://theconversation.com/victorias-fire-alert-has-knocked-australians-out-of-complacency-under-climate-change-catastrophic-bushfires-can-strike-any-time-224636">Victoria's fire alert has knocked Australians out of complacency. Under climate change, catastrophic bushfires can strike any time</a>
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<h2>More transparency is needed</h2>
<p>Australia’s modelling may be sophisticated but it can also be confusing – even for those who follow climate policy closely. One reason is the <a href="https://www.dcceew.gov.au/sites/default/files/documents/national-inventory-report-2021-volume-1.pdf">complex way</a> we differentiate between “natural” fires (those beyond human control) and “anthropogenic” or human-caused fires such as controlled fuel-reduction burns. </p>
<p>Emissions from natural fires are reported to the UNFCCC, but do not initially count towards Australia’s net emissions calculations. This is consistent with <a href="https://www.ipcc-nggip.iges.or.jp/public/2006gl/pdf/4_Volume4/V4_01_Ch1_Introduction.pdf">guidance</a> from the Intergovernmental Panel on Climate Change.</p>
<p>However, we believe that to improve transparency and accountability, the federal government should work with the states and territories to provide a separate breakdown of natural and human-caused fire emissions. This data should be made publicly available to provide a clearer picture of bushfire emissions and the impact of climate change on large fires.</p>
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Read more:
<a href="https://theconversation.com/fire-is-a-chemical-reaction-heres-why-australia-is-supremely-suited-to-it-217275">Fire is a chemical reaction. Here's why Australia is supremely suited to it</a>
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<h2>Where we must improve</h2>
<p>As mentioned above, emissions from natural fires do not initially count towards Australia’s net calculations. Consistent with other countries, our modelling assumes that emissions will be offset after the fires because forest regrowth captures carbon from the atmosphere. </p>
<p>This approach is based on current scientific evidence. For example, within two years of the Black Summer fires, <a href="https://www.abc.net.au/news/2024-01-22/are-megafires-contributing-to-climate-change/103219876">80% of the burned area</a> was almost fully recovered. </p>
<p>If monitoring of a fire site shows regrowth has not fully offset emissions after 15 years, the difference is retrospectively added to Australia’s net emissions for the year of the original fire.</p>
<p>But this approach may soon need to change. That’s because research <a href="https://cbmjournal.biomedcentral.com/articles/10.1186/s13021-023-00231-3">sugests</a> we cannot assume forests will recover quickly after bushfires. As bushfires become more frequent and intense, they are more likely to <a href="https://onlinelibrary.wiley.com/doi/10.1111/gcb.12433">irrevocably change</a> landscapes. Bushfires are also more likely to occur in areas that are not adapted to fire and recover poorly – such as <a href="https://www.nature.com/articles/nature.2016.19308">Tasmania’s World Heritage-listed northwest</a>. </p>
<p>This has major implications for Australia’s emissions accounting.</p>
<p>Another significant gap in our modelling is the contribution of soil carbon to bushfire emissions. Large amounts of carbon are present in organic material in soil.</p>
<p>Currently, international rules do not require soil carbon emissions from fire to be estimated. This is despite emerging research showing the release of <a href="https://www.publish.csiro.au/wf/pdf/WF22204">soil carbon</a> during bushfires in some landscapes, such as peatlands, is likely to create substantial emissions. <a href="https://www.nature.com/articles/nature24668">Other research</a> suggests that depleted soil carbon can slow the recovery of forests after fire.</p>
<p>There is currently insufficient evidence to include soil carbon emissions from bushfires in Australia’s estimates, or to model the effects of soil carbon changes on forest regrowth and carbon capture. More research is urgently needed.</p>
<h2>Where to now?</h2>
<p>Australia’s approach to estimating bushfire emissions is credible and sophisticated. However, our modelling and reporting must be refined as technology improves and the climate changes. </p>
<p>Australia is a fire-prone continent. Our bushfire emissions will increase unless we significantly improve our fire preparedness and management. We must also rapidly reduce emissions from other sectors, to ensure our country is playing its part in the struggle to avoid catastrophic global warming.</p><img src="https://counter.theconversation.com/content/224745/count.gif" alt="The Conversation" width="1" height="1" />
<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>Australia’s approach to estimating bushfire emissions is credible and sophisticated. But it must be refined as technology improves and the climate changes.Robert Hortle, Research Fellow, Tasmanian Policy Exchange, University of TasmaniaLachlan Johnson, Research fellow, University of TasmaniaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2207712024-01-19T13:40:44Z2024-01-19T13:40:44ZOld forests are critically important for slowing climate change and merit immediate protection from logging<figure><img src="https://images.theconversation.com/files/570228/original/file-20240118-23-ojgpd7.JPG?ixlib=rb-1.1.0&rect=6%2C13%2C2323%2C1893&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">An old-growth forest of noble fir trees at Marys Peak in Oregon's Coast Range.</span> <span class="attribution"><span class="source">Beverly Law</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span></figcaption></figure><p>Forests are an essential part of Earth’s operating system. They reduce the buildup of heat-trapping carbon dioxide in the atmosphere from fossil fuel combustion, deforestation and land degradation <a href="https://essd.copernicus.org/articles/15/5301/2023">by 30% each year</a>. This slows global temperature increases and the <a href="https://doi.org/10.5194/essd-14-4811-2022">resulting changes to the climate</a>. In the U.S., forests take up <a href="https://www.epa.gov/system/files/documents/2023-04/US-GHG-Inventory-2023-Main-Text.pdf">12% of the nation’s greenhouse gas emissions annually</a> and store the carbon long term in trees and soils.</p>
<p>Mature and old-growth forests, with larger trees than younger forests, play an outsized role in accumulating carbon and <a href="https://www.fs.usda.gov/sites/default/files/mature-and-old-growth-forests-tech.pdf">keeping it out of the atmosphere</a>. These forests are especially <a href="https://www.fs.usda.gov/sites/default/files/mature-and-old-growth-forests-tech.pdf">resistant to wildfires and other natural disturbances</a> as the climate warms.</p>
<p>Most forests in the continental U.S. have been harvested multiple times. Today, just 3.9% of timberlands across the U.S., in public and private hands, <a href="https://doi.org/10.2737/WO-GTR-97">are over 100 years old</a>, and most of these areas hold relatively little carbon compared with their potential. </p>
<p>The Biden administration is moving to <a href="https://www.federalregister.gov/documents/2022/04/27/2022-09138/strengthening-the-nations-forests-communities-and-local-economies">improve protection for old-growth and mature forests</a> on federal land, which we see as a welcome step. But this involves regulatory changes that will likely take several years to complete. Meanwhile, existing forest management plans that allow logging of these important old, large trees remain in place.</p>
<p>As scientists who have spent decades studying <a href="https://scholar.google.com/citations?user=J2KWqAoAAAAJ&hl=en">forest ecosystems</a> and <a href="https://www.researchgate.net/profile/William-Moomaw">the effects of climate change</a>, we believe that it is essential to start protecting carbon storage in these forests. In our view, there is ample scientific evidence to justify an immediate moratorium on logging mature and old-growth forests on federal lands. </p>
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<figcaption><span class="caption">Remote sensing data from space is a new tool for estimating forest growth and density.</span></figcaption>
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<h2>Federal action to protect mature and old-growth forests</h2>
<p>A week after his inauguration in 2021, President Joe Biden issued an executive order that set a goal of <a href="https://www.whitehouse.gov/briefing-room/presidential-actions/2021/01/27/executive-order-on-tackling-the-climate-crisis-at-home-and-abroad/">conserving at least 30%</a> of U.S. lands and waters by 2030 to address what the order called “a profound climate crisis.” In 2022, Biden recognized the climate importance of mature and old-growth forests for a healthy climate and <a href="https://www.federalregister.gov/documents/2022/04/27/2022-09138/strengthening-the-nations-forests-communities-and-local-economies">called for conserving them</a> on federal lands.</p>
<p>Most recently, in December 2023, the U.S. Forest Service announced that it was <a href="https://www.federalregister.gov/documents/2023/12/20/2023-27875/land-management-plan-direction-for-old-growth-forest-conditions-across-the-national-forest-system">evaluating the effects</a> of amending management plans for 128 U.S. national forests to better protect mature and old-growth stands – the first time any administration has taken this kind of action. </p>
<p>These actions seek to make existing old-growth forests more resilient; preserve ecological benefits that they provide, such as habitat for threatened and endangered species; establish new areas where <a href="https://www.fs.usda.gov/sites/default/files/mature-and-old-growth-forests-tech.pdf">old-growth conditions</a> can develop; and monitor the forests’ condition over time. The amended national forest management plans also would prohibit logging old-growth trees for mainly economic purposes – that is, producing timber. Harvesting trees would be permitted for other reasons, such as thinning to reduce fire severity in hot, dry regions where fires occur more frequently. </p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/570231/original/file-20240118-24-xa1x8n.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A woman rests her hand on the trunk of an enormous tree, looking up toward its crown." src="https://images.theconversation.com/files/570231/original/file-20240118-24-xa1x8n.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/570231/original/file-20240118-24-xa1x8n.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=800&fit=crop&dpr=1 600w, https://images.theconversation.com/files/570231/original/file-20240118-24-xa1x8n.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=800&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/570231/original/file-20240118-24-xa1x8n.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=800&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/570231/original/file-20240118-24-xa1x8n.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1005&fit=crop&dpr=1 754w, https://images.theconversation.com/files/570231/original/file-20240118-24-xa1x8n.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1005&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/570231/original/file-20240118-24-xa1x8n.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1005&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Forest biologist Beverly Law with an old-growth Douglas fir in Corvallis, Oregon.</span>
<span class="attribution"><span class="source">Beverly Law</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<p>Remarkably, however, logging is hardly considered in the Forest Service’s <a href="https://www.fs.usda.gov/sites/default/files/mature-and-old-growth-forests-tech.pdf">initial analysis</a>, although studies show that it causes greater carbon losses than wildfires and pest infestations. </p>
<p>In one analysis across 11 western U.S. states, researchers calculated total aboveground tree carbon loss from logging, beetle infestations and fire between 2003 and 2012 and found that <a href="https://doi.org/10.1038/s43247-021-00326-0">logging accounted for half of it</a>. Across the states of California, Oregon and Washington, harvest-related carbon emissions between 2001 and 2016 averaged <a href="http://dx.doi.org/10.1088/1748-9326/ab28bb">five times the emissions</a> from wildfires.</p>
<p>A 2016 study found that nationwide, between 2006 and 2010, total carbon emissions from logging were <a href="https://doi.org/10.1186/s13021-016-0066-5">comparable to emissions from all U.S. coal plants</a>, or to direct emissions from the entire building sector. </p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/569933/original/file-20240117-19-wsd8su.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Close-up of a furry animal with small rounded ears" src="https://images.theconversation.com/files/569933/original/file-20240117-19-wsd8su.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/569933/original/file-20240117-19-wsd8su.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=575&fit=crop&dpr=1 600w, https://images.theconversation.com/files/569933/original/file-20240117-19-wsd8su.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=575&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/569933/original/file-20240117-19-wsd8su.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=575&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/569933/original/file-20240117-19-wsd8su.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=723&fit=crop&dpr=1 754w, https://images.theconversation.com/files/569933/original/file-20240117-19-wsd8su.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=723&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/569933/original/file-20240117-19-wsd8su.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=723&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Pacific fishers (<em>Pekania pennanti</em>) are small carnivores related to minks and otters. They live in forests with large, mixed-tree canopy covers, mainly on federal land on the West Coast. A subpopulation in the southern Sierra Nevada is listed as endangered.</span>
<span class="attribution"><a class="source" href="https://flic.kr/p/9PufBo">Pacific Southwest Forest Service, USDA/Flickr</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<h2>Logging pressure</h2>
<p>Federal lands are used for multiple purposes, including biodiversity and water quality protection, recreation, mining, grazing and timber production. Sometimes, these uses can conflict with one another – for example, <a href="https://crsreports.congress.gov/product/pdf/R/R43429">conservation and logging.</a>.</p>
<p>Legal mandates to manage land for multiple uses do not explicitly consider climate change, and federal agencies <a href="https://doi.org/10.1002/ecs2.3286">have not consistently factored climate change science</a> into their plans. Early in 2023, however, the White House <a href="https://www.whitehouse.gov/ceq/">Council on Environmental Quality</a> directed federal agencies to consider the effects of climate change when they <a href="https://www.federalregister.gov/documents/2023/01/09/2023-00158/national-environmental-policy-act-guidance-on-consideration-of-greenhouse-gas-emissions-and-climate">propose major federal actions</a> that significantly affect the environment. </p>
<p>Multiple large logging projects on public land clearly qualify as major federal actions, but many thousands of acres have been <a href="https://www.law.cornell.edu/cfr/text/36/220.6">legally exempted</a> from such analysis. </p>
<p>Across the western U.S., <a href="https://doi.org/10.1038/s43247-021-00326-0">just 20% of relatively high-carbon forests</a>, mostly on federal lands, are protected from logging and mining. A study in the lower 48 states found that 76% of mature and old-growth forests on federal lands <a href="https://doi.org/10.3389/ffgc.2022.979528">are vulnerable to logging</a>. Harvesting these forests would release about <a href="https://doi.org/10.3390/land11050721">half of their aboveground tree carbon</a> into the atmosphere within one or two decades. </p>
<p>An analysis of <a href="https://doi.org/10.1029/2023AV000965">152 national forests</a> across North America found that five forests in the Pacific Northwest had the highest carbon densities, but just 10% to 20% of these lands were protected at the highest levels. The majority of national forest area that is mature and old growth is not protected from logging, and <a href="https://www.climate-forests.org/worth-more-standing">current management plans</a> include logging of some of the largest trees still standing. </p>
<h2>Letting old trees grow</h2>
<p>Conserving forests is one of the most effective and lowest-cost options for managing atmospheric carbon dioxide, and mature and old-growth forests do this job most effectively. Protecting and expanding them does not require expensive or complex energy-consuming technologies, unlike some other <a href="https://theconversation.com/why-the-oil-industrys-pivot-to-carbon-capture-and-storage-while-it-keeps-on-drilling-isnt-a-climate-change-solution-171791">proposed climate solutions</a>.</p>
<p>Allowing mature and old-growth forests to <a href="https://doi.org/10.3389/ffgc.2019.00027">continue growing</a> will remove from the air and store the largest amount of atmospheric carbon in the critical decades ahead. The sooner logging of these forests ceases, the more climate protection they can provide.</p>
<p><em><a href="https://www.woodwellclimate.org/staff/richard-birdsey/">Richard Birdsey</a>, a former U.S. Forest Service carbon and climate scientist and current senior scientist at the Woodwell Climate Research Center, contributed to this article.</em></p>
<p><em>This is an update of <a href="https://theconversation.com/the-biden-administration-has-called-for-protecting-mature-us-forests-to-slow-climate-change-but-its-still-allowing-them-to-be-logged-199845">an article</a> originally published on March 2, 2023.</em></p><img src="https://counter.theconversation.com/content/220771/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Beverly Law receives funding from the Conservation Biology Institute. </span></em></p><p class="fine-print"><em><span>William Moomaw receives funding from the Rockefeller Brothers Fund.
</span></em></p>President Biden has called for protecting large, old trees from logging, but many of them could be cut while the regulatory process grinds forward.Beverly Law, Professor Emeritus of Global Change Biology and Terrestrial Systems Science, Oregon State UniversityWilliam Moomaw, Professor Emeritus of International Environmental Policy, Tufts UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2113142023-11-03T12:44:47Z2023-11-03T12:44:47ZThe world’s boreal forests may be shrinking as climate change pushes them northward<figure><img src="https://images.theconversation.com/files/556952/original/file-20231031-29-4j1sin.JPG?ixlib=rb-1.1.0&rect=11%2C0%2C3854%2C2585&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">A brown bear in a Siberian boreal forest.</span> <span class="attribution"><span class="source">Logan Berner</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span></figcaption></figure><p>Earth’s <a href="https://www.britannica.com/science/taiga">boreal forests</a> circle our planet’s far northern reaches, just south of the Arctic’s treeless tundra. If the planet wears an Arctic ice cap, then the boreal forests are a loose-knit headband wrapped around its ears, covering large portions of Alaska, Canada, Scandinavia and Siberia. </p>
<p>The boreal region’s soils have long buffered the planet against warming by storing huge quantities of carbon and keeping it out of the atmosphere. Its remoteness has historically protected its forests and wetlands <a href="https://doi.org/10.1016/j.tree.2009.03.019">from extensive human impact</a>. </p>
<p>These two traits rank boreal forests <a href="https://unece.org/sites/default/files/2021-07/Why%20Boreal%20Forests%20Matter.pdf">among the most important ecosystems</a> on Earth. In addition, numerous species of <a href="https://doi.org/10.1007/978-3-319-71065-5_17-1">mammals, fish, plants, insects and birds</a> make these forests home.</p>
<p>For <a href="https://doi.org/10.1111/1365-2745.13109">over two centuries</a>, scientists have recognized that climate plays a key role in determining the geographic zones of plant communities. Because boreal forests and soils face subzero winters and short summers, these forests and the animals that live in them <a href="https://link.springer.com/chapter/10.1007/978-3-031-15988-6_30">are shifting northward as temperatures rise</a>.</p>
<p>However, boreal forests’ northward advance has been spotty and slower than expected. Meanwhile, their southern retreat has been faster than scientists predicted. As scholars who study <a href="https://scholar.google.com/citations?user=BQmOlMsAAAAJ&hl=en">northern</a> <a href="https://scholar.google.com/citations?user=RBKFcQQAAAAJ&hl=en">ecosystems</a>, <a href="https://scholar.google.com/citations?user=SX1wuUIAAAAJ&hl=en">forests</a> and <a href="https://scholar.google.com/citations?user=0kHNcjQAAAAJ&hl=en">wetlands</a>, we see concerning evidence that as the world warms, its largest forest wilderness appears to be shrinking.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/OUmHWrF8MnY?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">The boreal forest biome, often known by its original Russian name, the taiga, stretches from coast to coast in Earth’s far north.</span></figcaption>
</figure>
<h2>The largest wilderness on Earth</h2>
<p>Boreal forests contain billions of trees. Most are needleleaf, <a href="https://www.rbg.ca/evergreens-vs-conifers/">cone-bearing conifers</a>, but there also are patches of broadleaf species, including <a href="http://www.ramp-alberta.org/river/boreal/alberta/trees.aspx">birch, aspen and poplar</a>. They support millions of migratory birds and iconic mammals like brown bears, moose and lynx.</p>
<p>These trees and the soils around their roots help regulate Earth’s climate, in part by pulling carbon dioxide out of the atmosphere, where it would otherwise act as a greenhouse gas. The trees use this carbon to grow roots, trunks and leaves, which eventually turn into carbon-rich soil once the tree dies. Significant changes to the forests will translate to changes in global climate. </p>
<p>These forests are warming at rates <a href="https://doi.org/10.1038/s43247-022-00498-3">well above the global average</a>. Rising temperatures directly affect the growth and survival of trees and, in turn, their ability to store carbon.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/557135/original/file-20231101-19-jffqm6.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Graphic showing carbon storage by forest type." src="https://images.theconversation.com/files/557135/original/file-20231101-19-jffqm6.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/557135/original/file-20231101-19-jffqm6.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=285&fit=crop&dpr=1 600w, https://images.theconversation.com/files/557135/original/file-20231101-19-jffqm6.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=285&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/557135/original/file-20231101-19-jffqm6.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=285&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/557135/original/file-20231101-19-jffqm6.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=358&fit=crop&dpr=1 754w, https://images.theconversation.com/files/557135/original/file-20231101-19-jffqm6.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=358&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/557135/original/file-20231101-19-jffqm6.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=358&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Different forest types around the world store varying amounts of carbon. Warm tropical regions tend to store much more carbon in plants, while cool boreal forests have enormous carbon stores in soil.</span>
<span class="attribution"><a class="source" href="https://www.fs.usda.gov/ccrc/topics/global-carbon">U.S. Forest Service</a></span>
</figcaption>
</figure>
<h2>Forests on the move</h2>
<p>As atmospheric warming frees trees from the icy grip of cold temperatures, adult trees can respond by growing faster. Milder temperatures also allow young seedling trees in the most northern boreal forests to gain a foothold where previous conditions were too harsh for them to become established.</p>
<p>In the warmer, southern boreal forests, the situation is quite different. Here, conditions have become too warm for cold-adapted boreal trees, slowing their growth and even leading to their death. With warming comes dryness, and water stress leaves trees more susceptible to insect infestation and <a href="https://theconversation.com/more-frequent-fires-could-dramatically-alter-boreal-forests-and-emit-more-carbon-122355">fires</a>, as <a href="https://www.cbc.ca/news/science/2024-wildfire-season-el-nino-1.6978559">Canada has experienced in 2023</a> and Siberia in <a href="https://www.vox.com/2019/8/1/20750200/siberia-wildfire-russia-fire-smoke-trump-putin">2019</a> and <a href="https://news.mongabay.com/2020/07/photos-show-scale-of-massive-fires-tearing-through-siberian-forests/">2020</a>. </p>
<p>If this happens at a larger scale, southern boreal forest boundaries will thin and degrade, thereby retreating farther north, where temperatures are still suitable.</p>
<p>If boreal forests expand northward and retreat in the south at the same rates, they could slowly follow warming temperatures. However, our combined research using satellite and field data shows that the story is more complex. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/557275/original/file-20231102-23-r2kfff.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Flames and smoke rise above a stretch of conifers." src="https://images.theconversation.com/files/557275/original/file-20231102-23-r2kfff.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/557275/original/file-20231102-23-r2kfff.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/557275/original/file-20231102-23-r2kfff.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/557275/original/file-20231102-23-r2kfff.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/557275/original/file-20231102-23-r2kfff.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/557275/original/file-20231102-23-r2kfff.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/557275/original/file-20231102-23-r2kfff.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">Flames from the Donnie Creek wildfire burn along a ridgetop north of Fort St. John, British Columbia, Canada, on July 2, 2023. Fire is part of the ecology of boreal forests, but climate change is drying out trees and making them more fire-prone.</span>
<span class="attribution"><a class="source" href="https://newsroom.ap.org/detail/CanadaWildfiresPhotoGallery/0920472b516345429a090820278d423b/photo">AP Photo/Noah Berger</a></span>
</figcaption>
</figure>
<h2>Tracking forests from space</h2>
<p>Satellites are invaluable for tracking how boreal forests have changed in recent decades and whether these changes are consistent with an overall northward shift. Researchers can use satellites to monitor year-to-year changes in forest characteristics, such as annual tree growth and tree cover.</p>
<p>Our recent studies using satellite data showed that <a href="https://doi.org/10.1111/gcb.16121">tree growth</a> and <a href="https://doi.org/10.1038/s41467-023-39092-2">tree cover</a> increased from 2000 to 2019 throughout much of the boreal forest. These changes occurred mainly in the coldest northern areas. However, there was limited evidence to indicate that forests were expanding past current tree lines.</p>
<p>Our studies also revealed that tree growth and tree cover often decreased from 2000 to 2019 in warmer southern areas of the boreal forests. In these regions, hotter and drier conditions frequently reduced tree growth or killed individual trees, while wildfires and logging contributed to tree cover loss.</p>
<p>Satellite data makes it clear that climate change is affecting both the northern and southern margins of the boreal forest. However, if tree cover loss in the south occurs more rapidly than gains in the north, then the boreal forest will likely contract, rather than simply shifting northward. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/557133/original/file-20231101-25-nw5diu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Satellite map showing gains and losses in North American boreal forest tree cover" src="https://images.theconversation.com/files/557133/original/file-20231101-25-nw5diu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/557133/original/file-20231101-25-nw5diu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=343&fit=crop&dpr=1 600w, https://images.theconversation.com/files/557133/original/file-20231101-25-nw5diu.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=343&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/557133/original/file-20231101-25-nw5diu.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=343&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/557133/original/file-20231101-25-nw5diu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=432&fit=crop&dpr=1 754w, https://images.theconversation.com/files/557133/original/file-20231101-25-nw5diu.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=432&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/557133/original/file-20231101-25-nw5diu.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=432&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Satellite measurements show that plant growth widely increased along the cold northern margins of the boreal forest in recent decades, but it often decreased along the warm southern margins − potential early indicators that the boreal forest is beginning to migrate northward.</span>
<span class="attribution"><a class="source" href="https://doi.org/10.1111/gcb.16121">Logan Berner, based on results from Berner and Goetz 2022.</a>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<h2>Zooming in to understand forest change</h2>
<p>Forests advance when individual tree seeds germinate and grow, but boreal trees grow slowly and require decades to reach a size that’s visible from space. Finding young trees whose presence would signal tree-line movement requires data from the ground.</p>
<p>In the late 1970s, one of us (David Cooper) documented that young spruce trees were growing at altitudes hundreds of yards higher and locations miles north of the <a href="https://www.jstor.org/stable/40510488">highest-elevation cone-bearing trees</a> in Alaska’s Brooks Range. Returning in 2021, we found those little trees had grown to be several yards tall and were producing cones. More importantly, <a href="https://doi.org/10.1038/s41586-022-05093-2">10 times</a> the number of young spruces now grow above and beyond the tree line than during our first field forays. </p>
<p>Crisscrossing the boundary between Alaska’s boreal forest and its Arctic tundra on foot, we have found thousands of young boreal trees growing <a href="https://doi.org/10.1038/s41586-022-05093-2">up to 25 miles north of established tree lines</a>. Most grow where deeper snows fall, due to an Arctic Ocean version of the “<a href="https://www.weather.gov/safety/winter-lake-effect-snow">lake effect</a>”: Cold air moves across open water, picking up warmth and moisture, which then falls as snow downwind.</p>
<p>Retreating sea ice leaves more open water. This generates stronger winds that propel tree seeds farther and more snowfall that insulates seedlings from harsh winter conditions. The result is that trees in Alaska’s Brooks Range are <a href="https://static-content.springer.com/esm/art%3A10.1038%2Fs41586-022-05093-2/MediaObjects/41586_2022_5093_MOESM5_ESM.gif">rapidly moving into the treeless tundra</a>. However, these rapid expansions are localized and <a href="https://doi.org/10.1111/gcb.15113">do not yet happen everywhere along the northern tree line</a>. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/557270/original/file-20231102-25-zt8dre.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/557270/original/file-20231102-25-zt8dre.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/557270/original/file-20231102-25-zt8dre.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=338&fit=crop&dpr=1 600w, https://images.theconversation.com/files/557270/original/file-20231102-25-zt8dre.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=338&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/557270/original/file-20231102-25-zt8dre.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=338&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/557270/original/file-20231102-25-zt8dre.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=424&fit=crop&dpr=1 754w, https://images.theconversation.com/files/557270/original/file-20231102-25-zt8dre.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=424&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/557270/original/file-20231102-25-zt8dre.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">A young white spruce colonist on the Alaskan tundra, with the Brooks Range mountains in the background.</span>
<span class="attribution"><span class="source">Roman Dial</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<h2>The future face of boreal forests</h2>
<p>Our combined research shows that boreal forests are, in fact, responding to rising temperatures. But rapid rates of climatic change mean that trees likely can’t move northward at a pace that keeps up with their loss in the south. </p>
<p>Will trees in the far north ever catch up with climate and prevent forest contraction? At this point, scientists simply don’t know. Perhaps the newly established trees in the Brooks Range herald such an expansion. It’s also unclear whether the northern parts of boreal forests can accumulate enough carbon through increased growth to compensate for carbon losses in the south.</p>
<p>If boreal forests are indeed on the verge of contracting, they will eventually disappear from their current southern edge. This would harm many native and migratory animals, especially birds, by reducing their boreal habitat. The forests also are culturally important to several million people who call them home, such as <a href="https://natural-resources.canada.ca/our-natural-resources/forests/sustainable-forest-management/boreal-forest/8-facts-about-canadas-boreal-forest/17394">Canada’s aboriginal communities</a>.</p>
<p>Monitoring boreal forests around the world more closely, using both satellite data and on-the-ground measurements, will help fill out this picture. Only then can researchers hope to glimpse the future of <a href="https://www.nature.com/articles/d41586-018-07183-6">one of the Earth’s last wildernesses</a>.</p><img src="https://counter.theconversation.com/content/211314/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Ronny Rotbarth receives funding from the Dutch Ministry of Education, Culture and Science.</span></em></p><p class="fine-print"><em><span>David J. Cooper receives funding from the National Science Foundation, the US National Park Service, and National Forest Service.</span></em></p><p class="fine-print"><em><span>Logan Berner receives funding from the National Science Foundation and National Aeronautics and Space Administration.</span></em></p><p class="fine-print"><em><span>Roman Dial receives funding from the US National Science Foundation and NASA Alaska Space Grant. </span></em></p>How will Earth’s vast boreal forests look in a warmer world? Combining satellite-based research with fieldwork shows that the planet’s largest wilderness may be changing in unexpected ways.Ronny Rotbarth, Ph.D. Candidate of Arctic and Sub-Arctic Ecology, Wageningen UniversityDavid J. Cooper, Senior Research Scientist Emeritus, Colorado State UniversityLogan Berner, Assistant Research Professor of Global Change Ecology, Northern Arizona UniversityRoman Dial, Professor of Biology and Mathematics, Alaska Pacific UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2108802023-09-29T01:25:27Z2023-09-29T01:25:27ZHere’s how to fix Australia’s approach to soil carbon credits so they really count towards our climate goals<figure><img src="https://images.theconversation.com/files/550802/original/file-20230928-21-n9ydfs.jpg?ixlib=rb-1.1.0&rect=199%2C0%2C9290%2C6331&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/female-farmer-hold-soil-hands-monitoring-2346686237">William Edge, Shutterstock</a></span></figcaption></figure><p>Australia’s plan to achieve <a href="https://www.dcceew.gov.au/climate-change/emissions-reduction/net-zero">net zero</a> greenhouse gas emissions by 2050 relies heavily on carbon credits. </p>
<p>These <a href="https://www.cleanenergyregulator.gov.au/ERF/About-the-Emissions-Reduction-Fund">credits are awarded to projects</a> that avoid the release of greenhouse gases or remove and “sequester” (store) carbon so it’s no longer warming the atmosphere. </p>
<p>Farmers can be awarded credits for <a href="https://www.cleanenergyregulator.gov.au/ERF/Choosing-a-project-type/Opportunities-for-the-land-sector/Agricultural-methods/estimating-soil-organic-carbon-sequestration-using-measurement-and-models-method">increasing soil carbon content</a>. The federal government or companies can then purchase these credits to offset their carbon emissions. </p>
<p>These credits must represent genuine carbon sequestration if they are to mitigate climate change. </p>
<p>As Australian agricultural and soil scientists, we have serious concerns about the way credits are awarded for soil carbon sequestration under the <a href="https://www.cleanenergyregulator.gov.au/OSR/ANREU/types-of-emissions-units/australian-carbon-credit-units">Australian carbon credit unit scheme</a>. There are four main issues with the method that must be addressed as a matter of urgency.</p>
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<figcaption><span class="caption">Soil organic carbon is the treasure beneath our feet (Food and Agriculture Organization of the United Nations)</span></figcaption>
</figure>
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Read more:
<a href="https://theconversation.com/us-scheme-used-by-australian-farmers-reveals-the-dangers-of-trading-soil-carbon-to-tackle-climate-change-161358">US scheme used by Australian farmers reveals the dangers of trading soil carbon to tackle climate change</a>
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<h2>Understanding the carbon cycle</h2>
<p>Much like water, carbon cycles through the environment, moving between plants, the earth and the atmosphere. </p>
<p>Plants take in carbon dioxide from the atmosphere as they grow. The carbon is stored in the plant tissue. When plants die, or drop leaves, this carbon-rich organic matter enters the soil. Then it decomposes, releasing carbon dioxide back into the atmosphere. </p>
<p>When carbon inputs from plants exceed losses from the decomposition of organic matter, the amount of soil carbon increases. That means soil organic carbon is more likely to increase during good seasons when there’s plenty of rainfall available to support plant growth – such as during the recent three-year period of consecutive La Niña events.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/550131/original/file-20230925-15-sf72i6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Graphic illustrating how carbon cycles through agricultural systems" src="https://images.theconversation.com/files/550131/original/file-20230925-15-sf72i6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/550131/original/file-20230925-15-sf72i6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=309&fit=crop&dpr=1 600w, https://images.theconversation.com/files/550131/original/file-20230925-15-sf72i6.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=309&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/550131/original/file-20230925-15-sf72i6.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=309&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/550131/original/file-20230925-15-sf72i6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=388&fit=crop&dpr=1 754w, https://images.theconversation.com/files/550131/original/file-20230925-15-sf72i6.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=388&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/550131/original/file-20230925-15-sf72i6.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=388&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 carbon cycle.</span>
<span class="attribution"><span class="source">Richard Eckard, University of Melbourne</span></span>
</figcaption>
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<h2>Increases need to be due to management</h2>
<p>The recent <a href="https://www.abc.net.au/news/rural/2023-06-24/aus-farmers-to-earn-money-from-soil-carbon-under-new-methods/102213244">tranche</a> of credits awarded to soil carbon projects raises similar concerns to those that have been raised by experts about <a href="https://theconversation.com/australias-central-climate-policy-pays-people-to-grow-trees-that-already-existed-taxpayers-and-the-environment-deserve-better-186900">credits awarded to trees</a>. Namely, carbon credits are being awarded for changes associated with seasonal conditions (changes that would have happened anyway) rather than human actions.</p>
<p>The current soil carbon method awards credits when an increase in soil organic carbon is detected between two points in time. This is problematic because it can award credits to projects that report increases during relatively wet periods. </p>
<p>This is the case for <a href="https://carbonlink.com.au/wp-content/uploads/CarbonLink-ACCUs-Flow-Media-Release-June-2023-1.pdf">projects sampled in 2021</a>, directly after a period where conditions were unusually favourable for plant growth. That means credits were awarded for sequestration that had more to do with the weather than good management. </p>
<p>Where crediting occurs due to seasonal conditions, the scheme is not providing any true (<a href="https://law.anu.edu.au/sites/all/files/what_the_beare_and_chambers_report_really_found_and_a_critique_of_its_method_16_march_2022.pdf">additional</a>) climate change mitigation. </p>
<h2>Soil carbon can be lost</h2>
<p>Where soil carbon losses are greater than inputs, soil carbon stocks decline and sequestered carbon is released back to the atmosphere. The <a href="https://www.sciencedirect.com/science/article/pii/S0301479720301286">emissions can be rapid</a> and considerable. </p>
<p>Furthermore, modelling indicates it’s likely <a href="https://doi.org/10.1016/j.geoderma.2018.09.041">soil carbon could be lost</a> under the warmer and drier conditions of future climates. </p>
<p>Where a project loses soil carbon, the legislation does not require excess credits to be returned. Rather, a scheme-wide <a href="https://www.cleanenergyregulator.gov.au/ERF/Choosing-a-project-type/Opportunities-for-the-land-sector/Risk-of-reversal-buffer">buffer</a> generated from all sequestration projects covers such losses. </p>
<p>This approach is inequitable because all projects share the same burden of maintaining the buffer, irrespective of the risk of reversal of individual projects. </p>
<h2>Overinflated sequestration rates</h2>
<p>Based on a <a href="https://esajournals.onlinelibrary.wiley.com/doi/abs/10.1002/eap.1473?__cf_chl_tk=1zpwtYjrpjjoZAaRpgcOb5o7R5c_fLaqDx0tadA0kWA-1693540306-0-gaNycGzND1A">comprehensive global analysis</a>, the <a href="https://carbonlink.com.au/wp-content/uploads/CarbonLink-ACCUs-Flow-Media-Release-June-2023-1.pdf">number of carbon credits generated</a> by some Australian projects appears unrealistically high. The most likely reason for these large values is high rainfall, but the way the method works makes it impossible to know for sure because the impacts of management are not identified.</p>
<p>This is not the first time a soil carbon project has made <a href="https://theconversation.com/us-scheme-used-by-australian-farmers-reveals-the-dangers-of-trading-soil-carbon-to-tackle-climate-change-161358">unrealistic claims</a>. </p>
<p>In addition, <a href="https://carbonlink.com.au/wp-content/uploads/CarbonLink-ACCUs-Flow-Media-Release-June-2023-1.pdf">one project saw 44%</a> of the increase in soil carbon at depths below 30cm. This is an issue because published studies show soil carbon changes in deeper soil are <a href="https://www.sciencedirect.com/science/article/pii/S0167880923002785">relatively small</a> and happen slowly. We are concerned the reported changes may have more to do with the way they were calculated. </p>
<p>Currently, data used to calculate credits are not released by the scheme regulator so cannot be scientifically verified. The release of data under strict non-disclosure arrangements would allow scientists to assess the implementation of the method. This would provide confidence credits generated represent real climate change mitigation. </p>
<p>Increased transparency was a <a href="https://www.dcceew.gov.au/sites/default/files/documents/independent-review-accu-exec-summary.pdf">key recommendation</a> of the <a href="https://oia.pmc.gov.au/published-impact-analyses-and-reports/chubb-review-australian-carbon-credit-units">Chubb Review</a> of Australian Carbon Credit Units in 2022. </p>
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<em>
<strong>
Read more:
<a href="https://theconversation.com/chubb-review-of-australias-carbon-credit-scheme-falls-short-and-problems-will-continue-to-fester-197401">Chubb review of Australia's carbon credit scheme falls short – and problems will continue to fester</a>
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<h2>Contributing to our emissions targets?</h2>
<p>Australia’s emissions are reported annually to the United Nations in the national <a href="https://www.dcceew.gov.au/climate-change/publications/national-inventory-reports">greenhouse gas inventory</a>. These annual inventories show progress towards our declared emissions reduction targets. </p>
<p>The current inventory method used to account for changes in soil carbon uses coarse regional-level statistics. Changes to practices at farm level, such as grazing management, are not detected and will not be reflected in our national greenhouse gas accounts. Further, Australia reports changes in soil carbon for the top 30cm of the soil only whereas carbon credits are also awarded for changes that occur deeper in the soil. </p>
<p>This means some soil carbon credits the Australian government purchases do not count toward our emissions targets. It calls into question the effectiveness of using taxpayer funds to purchase soil carbon credits as a policy tool.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/australia-relies-on-controversial-offsets-to-meet-climate-change-targets-we-might-not-get-away-with-it-in-egypt-193460">Australia relies on controversial offsets to meet climate change targets. We might not get away with it in Egypt</a>
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<h2>Getting it right</h2>
<p>To address the issues we have identified, the measurement-based soil carbon <a href="https://www.cleanenergyregulator.gov.au/ERF/Choosing-a-project-type/Opportunities-for-the-land-sector/Agricultural-methods/estimating-soil-organic-carbon-sequestration-using-measurement-and-models-method">method</a> needs to be revised to only credit increases due to management. For instance, <a href="https://verra.org/methodologies/vm0042-methodology-for-improved-agricultural-land-management-v2-0/">the Verra scheme</a> in the international voluntary carbon market uses a method that minimises crediting for increases associated with rainfall. </p>
<p>To support revision of Australia’s scheme, scientists should be granted access to project data. Data could to be used to improve models in order to distinguish between climate and management effects. This would ensure the method is fit for purpose. </p>
<p>There also needs to be greater focus on monitoring changes in soil carbon. For a start, Australia’s <a href="https://www.tern.org.au/">Terrestrial Ecosystem Research Network</a> should be extended to include agricultural land. This would provide data to increase transparency, independence and rigour of soil carbon estimates. </p>
<p>The revisions we propose would help ensure investment in carbon credits contributes to our national emissions reduction targets and addresses the urgent challenge of climate change.</p>
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<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/a-tonne-of-fossil-carbon-isnt-the-same-as-a-tonne-of-new-trees-why-offsets-cant-save-us-200901">A tonne of fossil carbon isn't the same as a tonne of new trees: why offsets can't save us</a>
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<img src="https://counter.theconversation.com/content/210880/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Aaron Simmons is a Senior Research Scientist with the NSW Department of Primary Industries. Aaron has received funding from the Commonwealth and NSW governments for soil carbon research and policy development. </span></em></p><p class="fine-print"><em><span>Annette Cowie is a Senior Principal Research Scientist in the Climate Branch at the NSW Department of Primary Industries, and Adjunct Professor in the School of Environmental and Rural Science at the University of New England. She has received funding for soil carbon research from NSW and Commonwealth government programs. Annette is a member of Soil Science Australia, a not-for-profit, professional association for soil scientists, and on the Advisory Board of Australia New Zealand Biochar Industry Group. </span></em></p><p class="fine-print"><em><span>Dr Beverley Henry is an Adjunct Associate Professor at Queensland University of Technology. She has previously worked for, and received funding from, the Commonwealth and Queensland Governments, and has, or has previously held, science consulting and advisory roles with Australian and international government and agricultural organisations. </span></em></p><p class="fine-print"><em><span>Brian Wilson is a Professor in Terrestrial Carbon Management at the University of New England. He has received funding from the Commonwealth and State Government and from the Cotton Research and Development Corporation for research relevant to soil carbon.</span></em></p><p class="fine-print"><em><span>David Pannell is a professor in environmental economics and agricultural economics at the University of Western Australia. He has received funding from the Commonwealth Government and from Grains Research and Development Corporation for research relevant to soil carbon. </span></em></p><p class="fine-print"><em><span>David Rowlings is a Professor in Sustainable Agriculture at Queensland University of Technology. He receives funding from Meat and Livestock Australia and Department Agriculture, Forestry and Fisheries for soil carbon research. </span></em></p><p class="fine-print"><em><span>Elaine Mitchell is a Research Fellow at the Queensland University of Technology. She has received funding from the Commonwealth Government for soil carbon research. She is also the founder of Ecometric, which provides advisory services in the natural capital space, including advice to carbon project developers on approaches to stratification, soil sampling and soil carbon modelling.
</span></em></p><p class="fine-print"><em><span>Matthew Tom Harrison is an Associate Professor at the University of Tasmania. He has been awarded funding from State and Commonwealth Governments, as well as Research Development Corporations to research practices, skills and technologies for improving soil organic carbon sequestration.</span></em></p><p class="fine-print"><em><span>Peter Grace is Professor Global Change at Queensland University of Technology. He currently receives funding from the Grains Research and Development Corporation, Meat and Livestock Australia, the Dept of Climate Change Energy Environment and Water, National Collaborative Research Infrastructure Scheme - Terrestrial Ecosystem Research Network, AgriFutures, and AgriMix. He has previously received funding from the Clean Energy Regulator, the Dept of Agriculture Fisheries and Forestry, and Cotton Research and Development Corporation.</span></em></p><p class="fine-print"><em><span>Raphael Viscarra Rossel is a Professor of Soil and Landscape Science at Curtin University. Previously, he was a Senior Principal Research Scientist at CSIRO, where he received funding from the Commonwealth Government for developing innovative soil carbon measurement methods that aided the formulation of the soil carbon methodology.</span></em></p><p class="fine-print"><em><span>Richard Eckard receives funding from Meat and Livestock Australia and the Commonwealth of Australia on greenhouse gas emissions from agriculture and carbon farming. His science contributed to six Australian carbon credit methods. </span></em></p><p class="fine-print"><em><span>Warwick Badgery is a Research Leader with the NSW Department of Primary Industries and is an Honorary Senior Fellow at Melbourne University. He receives funding from Meat and Livestock Australia, the NSW and Federal Governments for research on climate mitigation and soil carbon. </span></em></p>A group of agricultural and soil scientists has serious concerns about the way credits are awarded for soil carbon sequestration in Australia.Aaron Simmons, Adjunct Senior Research Fellow, University of New EnglandAnnette Cowie, Adjunct Professor, University of New EnglandBeverley Henry, Adjunct Associate Professor, Queensland University of TechnologyBrian Wilson, Professor, University of New EnglandDavid Pannell, Director, Centre for Environmental Economics and Policy, The University of Western AustraliaDavid Rowlings, Professor, Queensland University of TechnologyElaine Mitchell, Research Fellow, Queensland University of TechnologyMatthew Tom Harrison, Associate Professor of Sustainable Agriculture, University of TasmaniaPeter Grace, Professor of Global Change, Queensland University of TechnologyRaphael Viscarra Rossel, Professor of Soil & Landscape Science, Curtin UniversityRichard Eckard, Professor & Director, Primary Industries Climate Challenges Centre, The University of MelbourneWarwick Badgery, Research Leader Pastures an Rangelands, The University of MelbourneLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2127002023-09-14T02:50:47Z2023-09-14T02:50:47ZHealthy soil can help grow more food and cut emissions – but government inaction means too much soil is being degraded<figure><img src="https://images.theconversation.com/files/546150/original/file-20230904-29-iz3bq6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">(Volodymyr Shtun/Shutterstock)</span></span></figcaption></figure><p>The soil beneath our feet is a living entity. It is home to many microbes on Earth responsible for crucial processes such as decomposition and supporting plant health.</p>
<p>Organic compounds in the soil, such as humus – made from decomposed plant and animal matter – play a crucial role in maintaining soil’s structure, by acting as a bonding agent between soil particles. Similar to the walls of a building, healthy soil acts as a structure that allows water to flow, prevents erosion and provides habitats for organisms.</p>
<p>Healthy soil also helps people get safe and nutritious food, and is especially important for people including farmers and indigenous communities in developing nations.</p>
<p>Yet, more than a third of the soil worldwide is <a href="https://www.fao.org/about/meetings/soil-erosion-symposium/key-messages/en/">now degraded</a>, or facing issues such as hardening, erosion, nutrient degradation and increased salinity.</p>
<p>Degraded soil <a href="https://www.sciencedirect.com/topics/earth-and-planetary-sciences/soil-degradation">can result</a> in lower crop yields and poorer food quality. It also reduces water supply and increases drought risks. It may also increase the risks for floods, as the soil loses its ability to hold and filter water.</p>
<p>This article will share major factors behind soil degradation, and why we need governments worldwide to do more to take better care of our soil. </p>
<h2>Soil destroyers</h2>
<p>The global agriculture industry’s excessive use of fertiliser seriously damages the microbiological ecosystem in soil. This in turn makes the industry more dependent on expensive fertiliser and pesticides.</p>
<p>Modern ways of growing crops such as corns and potatoes often prioritise maximising high yields by using more nitrogen fertiliser than necessary. This releases nitrous oxide – a greenhouse gas <a href="https://www.bbc.com/future/article/20210603-nitrous-oxide-the-worlds-forgotten-greenhouse-gas">300 times more potent</a> than carbon dioxide at trapping heat in the atmosphere.</p>
<p>In addition, aggressive soil cultivation practices – such as deep plowing with heavy machinery – have risen significantly <a href="https://www.nytimes.com/1998/04/05/us/deep-plowing-is-halted-by-many-to-protect-soil.html">over recent decades</a>. These practices crush organic matter hidden within soil clumps, resulting in serious loss of biodiversity.</p>
<p>Human activities are putting too much stress on soil resources, and we are reaching a point where the soil can <a href="https://www.unccd.int/sites/default/files/2018-06/17.%20Threats%2Bto%2BSoils__Pierzynski_Brajendra.pdf">no longer sustain us</a>. This not only endangering biodiversity but also disrupting food supplies, potentially pushing millions into poverty.</p>
<h2>The global significance of healthy soil</h2>
<p><a href="https://www.iucn.org/news/ecosystem-management/202009/farmers-could-substantially-boost-productivity-conserving-soil-biodiversity-iucn-report">A 2020 study</a> by the International Union for Conservation of Nature found that healthy soils and landscapes can enhance crops’ ability to withstand the detrimental effects of climate change, such as drought or flood. </p>
<p>Improving our understanding of soil can also advance economic and climate goals.</p>
<p><a href="https://portals.iucn.org/library/node/49094">The IUCN report</a> found that increasing soil organic carbon by 0.4% annually in the first 30-40cm of soil may increase global production of major food crops, such as corn, rice and wheat, in some cases between 20-40% per year. </p>
<p>Boosting soil organic carbon in the world’s agricultural land by that much could increase carbon capture by croplands and grasslands by approximately <a href="https://portals.iucn.org/library/node/49094">1 gigatonne</a> per year over the next 30 years. That would be equivalent to capturing 10% of the world’s greenhouse gas emissions from human activity in 2017. </p>
<p>However, enhancing soil fertility is not as simple as pouring fertiliser out of a bag. Governments need to work together at the global, regional, and national levels to collectively improve soil health.</p>
<h2>Better policies to soil museums: how governments can help</h2>
<p>There are many existing soil initiatives around the world that governments can learn from. </p>
<p><strong>First,</strong> governments need to create policies that encourage farmers or land managers to implement environmentally friendly practices.</p>
<p>One example is the <a href="https://agriculture.ec.europa.eu/common-agricultural-policy/cap-overview/cap-glance_en">“carbon farming” policy</a> implemented by the European Union, which provides financial incentives to farmers or land managers who adopt eco-friendly practices. These practices include diversifying crops, planting leguminous plants, such as peanuts or lentils, and practising agroforestry (integrating trees and shrubs with crops or livestock).</p>
<p>These actions help to increase carbon sequestration in soils and support a healthy ecosystem with beneficial organisms, such as bacteria, fungi, protozoa and nematodes.</p>
<p>Brazil, China, India, Indonesia and Thailand <a href="https://web.kominfo.go.id/sites/default/files/G20%20Bali%20Leaders%27%20Declaration%2C%2015-16%20November%202022%2C%20incl%20Annex.pdf">have led globally</a> in reducing chemical fertiliser subsidies. To improve soil fertility and biodiversity, governments need to direct subsidies towards a biological solution that involves using bio-fertilisers and science-based composting.</p>
<p><strong>Second,</strong> governments can participate in global initiatives aimed at improving soil quality.</p>
<p>International organisations, such as the UN Sustainable Development Solutions Network, bring together experts, governments, the private sector and environmental organisations to emphasise critical environmental issues, including the significance of soil health. </p>
<p>The upcoming UN SDG Summit and UN Climate Change Conference (<a href="https://unfccc.int/cop28">COP28</a>) later in the year present opportunities for governments to recognise the feasibility and economic viability of large-scale soil ecosystem restoration.</p>
<p><strong>Third</strong>, educating the general public about soil science is also essential.</p>
<p>For instance, <a href="https://www.sciencedirect.com/science/article/abs/pii/S0065211320301024">soil museums</a> – located in various regions around the world – serve as an effective means of educating people about different types of soil, how they are formed, their uses and threats, as well as ways to protect it.</p>
<p>Nurturing the symbiotic relationship between human and life in soil requires a mindset change. Doing so will improve citizens’ understanding and respect for the nutrient recycling mechanisms that nature itself has developed and relies on.</p><img src="https://counter.theconversation.com/content/212700/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Yuen Yoong Leong, Director of Sustainability Studies, UN Sustainable Development Solutions Network (SDSN); Professor, Sunway University, and Michael James Platts (1945-2022), University of Cambridge</span></em></p>From policies to support carbon farming, to setting up local ‘soil museums’, governments need to do much more to protect the soil we rely on for growing food and a healthier life on Earth.Yuen Yoong Leong, Director of Sustainability Studies, UN Sustainable Development Solutions Network (SDSN); Professor, Sunway University, Sunway UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2065432023-07-19T14:59:40Z2023-07-19T14:59:40ZA hundred years of logging threatens the Innu link to their land<figure><img src="https://images.theconversation.com/files/528930/original/file-20230529-34716-q1m1w7.JPG?ixlib=rb-1.1.0&rect=17%2C0%2C1920%2C1273&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Woodland caribou of the Pipmuacan herd. The effects of predation and habitat loss have greatly contributed to the decline of caribou in southern Nitassinan.</span> <span class="attribution"><span class="source">(Stéphane Bourassa, Canadian Forest Service)</span></span></figcaption></figure><p>“Nutshimit,” which means “the interior of the land,” is <a href="https://ici.radio-canada.ca/nouvelle/1178729/mot-prefere-innu-josephine-bacon">Innu poet Joséphine Bacon’s favourite word</a> because it is intimately linked to Innu identity. Nutshimit, the place where the Innu soul is deposited, is what created the links with the land that have ensured the survival and cultural and social development of the Innu over the millennia. </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>
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<p>Atik, the woodland caribou, is the most important element that has helped foster links between the Innu and the land. Unfortunately, the interior has been undergoing major transformations for several years now. </p>
<p>So much so that in the southern part of the Nitassinan of the Innu of Pessamit, on Québec’s North Shore, this age-old link with the land is being erased as logging continues to move inexorably northwards. </p>
<p>As researchers, biologists (including one of Innu origin) and forestry engineers, we are at the interface of scientific and Indigenous knowledge. The forest environment is changing as a result of human activity. We are trying to gain a better understanding of how this is happening in order to guide future actions to preserve all the values that the forest represents, including Innu culture. </p>
<h2>The Nitassinan of Pessamit</h2>
<p>The Nitassinan of Pessamit is a vast territory within the boreal forest of eastern Québec. </p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/538158/original/file-20230718-21-c6fftb.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/538158/original/file-20230718-21-c6fftb.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/538158/original/file-20230718-21-c6fftb.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=1100&fit=crop&dpr=1 600w, https://images.theconversation.com/files/538158/original/file-20230718-21-c6fftb.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=1100&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/538158/original/file-20230718-21-c6fftb.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=1100&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/538158/original/file-20230718-21-c6fftb.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1382&fit=crop&dpr=1 754w, https://images.theconversation.com/files/538158/original/file-20230718-21-c6fftb.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1382&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/538158/original/file-20230718-21-c6fftb.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1382&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">Boundaries of Nitassinan of Pessamit. (David Gervais), Provided by the author.</span>
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<p>This territory stretches from the shores of the Gulf of St. Lawrence to the edge of the Caniapiscau Reservoir. </p>
<p>There are three bioclimatic zones here (plant associations in balance with the regional climate): the southern one is the Balsam fir-White birch domain; in the centre is the black spruce-moss domain; and in the north the spruce-lichen domain. </p>
<p>René-Levasseur Island corresponds approximately to the northern limit of commercial logging. North of this limit, the forests are generally not productive enough to allow forest management. Logging operations are therefore concentrated in the southern portion of Nitassinan, an area approximately 60,000 km<sup>2</sup>, or twice the size of Belgium.</p>
<h2>A changing forest landscape</h2>
<p>Forest fires and, to a lesser extent, disturbance by insect pests help to regenerate the forests of Nitassinan. Because of the maritime climate and rugged terrain, fires, although present, are not very <a href="https://cdnsciencepub.com/doi/10.1139/X07-201">frequent</a> in the area. This allows forests to develop over very long periods free of disturbance.</p>
<p>As a result, the pre-colonial landscape of Nitassinan was heavily dominated by old-growth forests. It is estimated that over 70 per cent of the forested area was dominated by forests over 100 years old, 50 per cent of which were over 200 years old. We can imagine a matrix of old-growth forests that formed the backdrop to the forest landscape, with patches of younger forests superimposed as a result of the passage of fire. </p>
<p>Since the forest colonized Québec’s North Shore following the retreat of the glaciers, the proportion of old-growth forest has varied over time with climate fluctuation, while remaining the dominant component of the landscape. It is in this type of landscape that Innu culture has flourished.</p>
<h2>Old but rich forests</h2>
<p>Contrary to what is often said in forestry circles, old-growth forests in the boreal zone are not stands in decline, vulnerable to insects and disease. In fact, the absence of fire over very long periods allows forests to acquire characteristics that are absent from younger forests. For example, old-growth forests typically have a diversity of tree sizes and ages. </p>
<p>With the passage of time, these forests become reservoirs of dead wood and soil carbon. Many of the species found in old-growth forests are associated with these characteristics or require a lot of time without major disturbance to grow and become established. </p>
<h2>The forest is getting younger from south to north</h2>
<p>Since the early 1970s, Québec has periodically carried out an ecoforest inventory to obtain the knowledge necessary to <a href="https://mffp.gouv.qc.ca/les-forets/inventaire-ecoforestier/">plan sustainable forest management</a>. </p>
<p>Part of the data is obtained using aerial photographs of the entire forested area of southern Québec. These photographs are interpreted, and the boundaries of forest stands are drawn taking into account a number of variables. These include species composition, tree height, canopy density, forest age and natural and anthropogenic disturbances. </p>
<p>Thus, for the southern portion of Nitassinan, we documented the progression of logging and forest fires in order to assess their impact on the state of the forest, which has mainly been the disappearance of old-growth forests.</p>
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<img alt="" src="https://images.theconversation.com/files/527838/original/file-20230523-15-i7karo.gif?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/527838/original/file-20230523-15-i7karo.gif?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=776&fit=crop&dpr=1 600w, https://images.theconversation.com/files/527838/original/file-20230523-15-i7karo.gif?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=776&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/527838/original/file-20230523-15-i7karo.gif?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=776&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/527838/original/file-20230523-15-i7karo.gif?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=976&fit=crop&dpr=1 754w, https://images.theconversation.com/files/527838/original/file-20230523-15-i7karo.gif?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=976&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/527838/original/file-20230523-15-i7karo.gif?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=976&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">Progression of logging and forest fires in the southern Nitassinan of Pessamit. (David Gervais), Provided by the author.</span>
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<p>Although logging does not lead to deforestation, its impact on forest landscapes results from the rate of harvesting and the spatial extent of interventions, <a href="https://link.springer.com/article/10.1007/s10980-015-0220-6">which exceed natural disturbances</a>. </p>
<p>Ecosystem-based management, in which <a href="https://esajournals.onlinelibrary.wiley.com/doi/abs/10.1890/080088">the impact of harvesting on the forest would be within the limits of the variability imposed by natural disturbances</a>, would guarantee the maintenance of biodiversity and Indigenous cultural practices. </p>
<h2>Rate of cutting accelerating</h2>
<p>Unlike forest fires, cutting exclusively targets mature forest stands, including old growth forests.</p>
<p>By comparing forest inventory data from the late 1980s with similar data from the current period (2019), we can see the decline of old growth forests south of the 50<sup>th</sup> parallel north. Since the start of logging predated the 1980s, the proportion of old forests there was already reduced in comparison to north of the 50<sup>th</sup> parallel (21 per cent of old growth forests remain south of the 50<sup>th</sup> parallel north, compared to 57 per cent in the north).</p>
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<img alt="" src="https://images.theconversation.com/files/527839/original/file-20230523-15345-o3zyyd.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/527839/original/file-20230523-15345-o3zyyd.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=484&fit=crop&dpr=1 600w, https://images.theconversation.com/files/527839/original/file-20230523-15345-o3zyyd.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=484&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/527839/original/file-20230523-15345-o3zyyd.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=484&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/527839/original/file-20230523-15345-o3zyyd.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=608&fit=crop&dpr=1 754w, https://images.theconversation.com/files/527839/original/file-20230523-15345-o3zyyd.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=608&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/527839/original/file-20230523-15345-o3zyyd.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=608&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">Average size of continuous forest patches by age class. (David Gervais), Provided by the author.</span>
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<p>Although logging is more recent in the north, large tracts of old growth forests over 1,000 km<sup>2</sup> now occupy barely 20 per cent of the landscape, whereas they represented double of that 30 years ago. These large tracts are essential for the maintenance of vulnerable species, such as the woodland caribou.</p>
<h2>Devastating consequences</h2>
<p>The northward expansion of forestry operations and the accelerated rate of logging, in addition to natural disturbances and the fragmentation of old-growth forests, are having a direct impact on the biodiversity and cultural practices of the Innu. </p>
<p>For example, the steady increase in moose and its main predator, the wolf, since the 1990s is a direct consequence of forestry operations and forest rejuvenation. The arrival of moose and wolves in the habitat of woodland caribou has had devastating consequences for the latter. Predation pressure and habitat loss have contributed significantly to the decline of caribou in southern Nitassinan. </p>
<p>This has also had a major impact on traditional Innu culture, given their age-old link with the woodland caribou. For over fifteen years now, the Innu of Pessamit have stopped hunting caribou in the hope of contributing to its recovery. They are also investing in land protection with the aim of protecting the Pipmuacan herd.</p>
<p>Despite the major transformations that Nitassinan has undergone in recent decades, there is still time to preserve and restore the land, its biodiversity, the woodland caribou and Innu culture, while maintaining a truly sustainable economic activity. </p>
<p>That’s the challenge facing the Innu people, who have lived on the land for millennia.</p><img src="https://counter.theconversation.com/content/206543/count.gif" alt="La Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Les auteurs ne travaillent pas, ne conseillent pas, ne possèdent pas de parts, ne reçoivent pas de fonds d'une organisation qui pourrait tirer profit de cet article, et n'ont déclaré aucune autre affiliation que leur organisme de recherche.</span></em></p>A realistic look at forest management on the Nitassinan of Pessamit, based on data from the Québec government’s forest inventories.Louis De Grandpré, Chercheur en écologie forestière, Conseil des Innus de Pessamit et professeur associé, Université du Québec à Montréal (UQAM)David Gervais, Biologiste Forestier, Conseil des Innus de PessamitÉric Kanapé, Biologiste, Conseil des Innus de PessamitMarie-Hélène Rousseau, Ingénieure forestière, Conseil des Innus de PessamitLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2025552023-05-08T12:19:43Z2023-05-08T12:19:43ZThese four challenges will shape the next farm bill – and how the US eats<figure><img src="https://images.theconversation.com/files/524429/original/file-20230504-15-4xz4fi.jpg?ixlib=rb-1.1.0&rect=31%2C15%2C5161%2C3425&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Small-scale farmers, organic producers and local markets receive a tiny fraction of farm bill funding.</span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/news-photo/fresh-produce-at-the-waverly-market-baltimore-maryland-news-photo/1296520990">Edwin Remsberg/VWPics/Universal Images Group/Getty Images</a></span></figcaption></figure><p>For the 20th time since 1933, Congress is writing a multiyear farm bill that will shape what kind of food U.S. farmers grow, how they raise it and how it gets to consumers. These measures are large, complex and expensive: The next farm bill is projected to cost taxpayers <a href="https://farmdocdaily.illinois.edu/2023/02/a-view-of-the-2023-farm-bill-from-the-cbo-baseline.html">US$1.5 trillion</a> over 10 years. </p>
<p>Modern farm bills address many things besides food, from rural broadband access to biofuels and even help for small towns to buy police cars. These measures bring out a dizzying range of interest groups with diverse agendas.</p>
<p>Umbrella organizations like the <a href="https://www.fb.org/files/2023-Farm-Bill-Priorities-FINAL-23.0119.pdf">American Farm Bureau Federation</a> and the <a href="https://nfu.org/wp-content/uploads/2023/03/2023-NFU-Special-Order-of-Business-Farm-Bill.pdf">National Farmers Union</a> typically focus on farm subsidies and crop insurance. The <a href="https://sustainableagriculture.net/wp-content/uploads/2022/11/2023-Farm-Bill-Platform.pdf">National Sustainable Agriculture Coalition</a> advocates for small farmers and ranchers. Industry-specific groups, such as <a href="https://www.ncba.org/Media/NCBAorg/Docs/jan-2023-farm-bill-one-pager.pdf">cattlemen</a>, <a href="https://www.wga.com/wp-content/uploads/d7files/Farm%20Bill%20Cover%20Letter-Formatted%20v2.pdf">fruit and vegetable growers</a> and <a href="https://ota.com/sites/default/files/indexed_files/2023%20Farm%20Bill%20Platform%20Priorities.pdf">organic producers</a>, all have their own interests. </p>
<p><a href="https://files.worldwildlife.org/wwfcmsprod/files/Publication/file/4ts36tbe1v_Farm_Bill_Recommendations_Final.pdf?_ga=2.63891951.1986224278.1680824658-413312318.1680545091">Environmental</a> and <a href="https://farmland.org/wp-content/uploads/2022/10/AFT_2023_Farm_Bill_Recommendations_Summary.pdf">conservation groups</a> seek to influence policies that affect land use and sustainable farming practices. <a href="https://www.cspinet.org/sites/default/files/2023-01/NANA%20Combined%20Farm%20Bill%20Priorities.pdf">Hunger and nutrition groups</a> target the bill’s sections on food aid. <a href="https://www.naco.org/resources/2023-farm-bill-primer">Rural counties</a>, <a href="https://www.trcp.org/wp-content/uploads/2023/02/TRCP-AWWG-2023-FB-Platform_1-31-23.pdf">hunters and anglers</a>, <a href="https://www.aba.com/-/media/documents/testimonies-and-speeches/aba-statement-for-the-record-farm-bill-2023.pdf?rev=c490c77291fb4781b4e999b4d127e1de">bankers</a> and dozens of other organizations have their own wish lists.</p>
<p>As a <a href="https://sustainability-innovation.asu.edu/person/kathleen-merrigan/">former Senate aide and senior official</a> at the U.S. Department of Agriculture, I’ve seen this intricate process from all sides. In my view, with the challenges in this round so complex and with critical 2024 elections looming, it could take Congress until 2025 to craft and enact a bill. Here are four key issues shaping the next farm bill, and through it, the future of the U.S. food system. </p>
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<h2>The price tag</h2>
<p>Farm bills always are controversial because of their high cost, but this year the timing is especially tricky. In the past two years, Congress has enacted major bills to <a href="https://www.whitehouse.gov/american-rescue-plan/">provide economic relief from the COVID-19 pandemic</a>, <a href="https://www.whitehouse.gov/briefing-room/statements-releases/2022/08/15/by-the-numbers-the-inflation-reduction-act/">counter inflation</a>, <a href="https://www.whitehouse.gov/briefing-room/statements-releases/2021/11/06/fact-sheet-the-bipartisan-infrastructure-deal/">invest in infrastructure</a> and <a href="https://www.whitehouse.gov/briefing-room/statements-releases/2022/08/09/fact-sheet-chips-and-science-act-will-lower-costs-create-jobs-strengthen-supply-chains-and-counter-china/">boost domestic manufacturing</a>. </p>
<p>These measures follow <a href="https://www.politico.com/news/2020/07/14/donald-trump-coronavirus-farmer-bailouts-359932">unprecedented spending</a> for farm support during the Trump administration. Now legislators are jockeying over <a href="https://theconversation.com/why-america-has-a-debt-ceiling-5-questions-answered-164977">raising the debt ceiling</a>, which limits how much the federal government can borrow to pay its bills.</p>
<p><a href="https://fj-corp-pub.s3.us-east-2.amazonaws.com/inline-files/FY24%20Views%20and%20Estimates%20Letter%20-%20final.pdf">Agriculture Committee leaders</a> and <a href="https://soygrowers.com/wp-content/uploads/2023/03/Farm-Bill-Budget-Letter-3-14-2023-FINAL.pdf">farm groups</a> argue that more money is necessary to strengthen the food and farm sector. If they have their way, the price tag for the next farm bill would increase significantly from current projections. </p>
<p>On the other side, <a href="https://www.rstreet.org/research/the-shaky-foundations-of-modern-farm-policy/">reformers argue</a> for <a href="https://www.ewg.org/research/updated-ewg-farm-subsidy-database-shows-largest-producers-reap-billions-despite-climate">capping payments to farmers</a>, which The Washington Post recently described as an “expensive <a href="https://www.washingtonpost.com/opinions/2023/05/05/congress-farm-bill-subsidies-debt/">agricultural safety net</a>,” and restricting payment eligibility. In their view, too much money goes to very large farms that produce <a href="https://www.fao.org/3/w3240e/w3240e06.htm">commodity crops</a> like wheat, corn, soybeans and rice, while small and medium-size producers receive far less support.</p>
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<h2>Food aid is the key fight</h2>
<p>Many people are surprised to learn that nutrition assistance – mainly through the <a href="https://www.fns.usda.gov/snap/supplemental-nutrition-assistance-program">Supplemental Nutrition Assistance Program</a>, formerly known as food stamps – is where most farm bill money is spent. Back in the 1970s, Congress began including nutrition assistance in the farm bill to secure votes from an increasingly urban nation. </p>
<p>Today, <a href="https://www.cbpp.org/research/food-assistance/the-supplemental-nutrition-assistance-program-snap">over 42 million Americans depend on SNAP</a>, including nearly 1 in every 4 children. Along with a few smaller programs, SNAP will likely consume 80% of the money in the new farm bill, up from <a href="https://www.ers.usda.gov/agriculture-improvement-act-of-2018-highlights-and-implications/">76% in 2018</a>. </p>
<p>Why have SNAP costs grown? During the pandemic, SNAP benefits were increased on an emergency basis, but that temporary arrangement <a href="https://theconversation.com/extra-snap-benefits-are-ending-as-us-lawmakers-resume-battle-over-program-that-helps-low-income-americans-buy-food-199929">expired in March 2023</a>. Also, in response to a directive included in the 2018 farm bill, the Department of Agriculture recalculated what it takes to afford a healthy diet, known as the <a href="https://www.fns.usda.gov/snap/thriftyfoodplan">Thrifty Food Plan</a>, and determined that it required an additional $12-$16 per month per recipient, or 40 cents per meal. </p>
<p>Because it’s such a large target, SNAP is where much of the budget battle will play out. Most Republicans typically seek to rein in SNAP; most Democrats usually support expanding it.</p>
<p>Anti-hunger advocates are lobbying to make the increased pandemic benefits permanent and defend the revised Thrifty Food Plan. In contrast, Republicans are calling for SNAP reductions, and are particularly focused on expanding <a href="https://georgiarecorder.com/2023/03/28/usda-secretary-battles-with-u-s-house-republicans-over-costs-of-federal-nutrition-programs/">work requirements</a> for recipients. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/524514/original/file-20230504-19-qqkzt9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Groceries on a kitchen counter." src="https://images.theconversation.com/files/524514/original/file-20230504-19-qqkzt9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/524514/original/file-20230504-19-qqkzt9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/524514/original/file-20230504-19-qqkzt9.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/524514/original/file-20230504-19-qqkzt9.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/524514/original/file-20230504-19-qqkzt9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/524514/original/file-20230504-19-qqkzt9.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/524514/original/file-20230504-19-qqkzt9.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">Jaqueline Benitez puts away groceries at her home in Bellflower, Calif., Feb. 13, 2023. Benitez, 21, works as a preschool teacher and depends on SNAP benefits to help pay for food.</span>
<span class="attribution"><a class="source" href="https://newsroom.ap.org/detail/FoodStamps/95413d28987347f09dfc93598e7dbb45/photo">AP Photo/Allison Dinner</a></span>
</figcaption>
</figure>
<h2>Debating climate solutions</h2>
<p>The 2022 <a href="https://www.scientificamerican.com/article/biden-signs-historic-climate-bill-as-scientists-applaud/">Inflation Reduction Act</a> provided $19.5 billion to the Department of Agriculture for programs that address climate change. Environmentalists and farmers alike <a href="https://www.farmanddairy.com/news/farm-conservation-groups-applaud-climate-ag-funding/730970.html">applauded this investment</a>, which is intended to help the agriculture sector embrace climate-smart farming practices and move toward markets that reward carbon sequestration and other ecosystem services. </p>
<p>This big pot of money has become a prime target for members of Congress who are <a href="https://www.agriculture.com/news/business/gop-senators-eye-climate-bill-funding-as-way-to-fatten-farm-bill-accounts">looking for more farm bill funding</a>. On the other side, conservation advocates, sustainable farmers and progressive businesses oppose diverting climate funds for other purposes. </p>
<p>There also is growing demand for Congress to require USDA to develop better standards for measuring, reporting and verifying actions designed to <a href="https://www.fsa.usda.gov/news-room/news-releases/2021/usda-announces-new-initiative-to-quantify-climate-benefits-of-conservation-reserve-program">protect or increase soil carbon</a>. Interest is rising in “<a href="https://www.spglobal.com/esg/insights/topics/carbon-farming-opportunities-for-agriculture-and-farmers-to-gain-from-decarbonization">carbon farming</a>” – paying farmers for practices such as <a href="https://theconversation.com/restoring-soil-can-help-address-climate-change-121733">no-till agriculture and planting cover crops</a>, which some studies indicate can <a href="https://rodaleinstitute.org/why-organic/issues-and-priorities/carbon-sequestration/">increase carbon storage in soil</a>. </p>
<p>But without more research and standards, observers worry that investments in climate-smart agriculture will support <a href="https://www.fastcompany.com/90796487/is-regenerative-agriculture-the-future-of-farming-or-the-next-greenwashing-fad">greenwashing</a> – misleading claims about environmental benefits – rather than a fundamentally different system of production. <a href="https://thefern.org/2022/12/a-pillar-of-the-climate-smart-agriculture-movement-is-on-shaky-ground/">Mixed research results</a> have raised questions as to whether establishing carbon markets based on such practices is premature. </p>
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<h2>A complex bill and inexperienced legislators</h2>
<p>Understanding farm bills requires highly specialized knowledge about issues ranging from crop insurance to nutrition to forestry. Nearly one-third of current members of Congress were first elected after the 2018 farm bill was enacted, so this is their first farm bill cycle. </p>
<p>I expect that, as often occurs in Congress, new members will follow more senior legislators’ cues and go along with traditional decision making. This will make it easier for entrenched interests, like the American Farm Bureau Federation and major commodity groups, to maintain support for <a href="https://www.ers.usda.gov/topics/farm-economy/farm-commodity-policy/title-i-crop-commodity-program-provisions/">Title I programs</a>, which provide revenue support for major commodity crops like corn, wheat and soybeans. These programs are complex, cost billions of dollars and go mainly to large-scale operations.</p>
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<iframe width="440" height="260" src="https://www.youtube.com/embed/6Sz9PJ5BUc4?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">How the U.S. became a corn superpower.</span></figcaption>
</figure>
<p>Agriculture Secretary Tom Vilsack’s current stump speech spotlights the fact that 89% of U.S. farmers <a href="https://civileats.com/2022/06/02/field-report-tom-vilsack-usda-food-system-transformation-climate-equity-justice/">failed to make a livable profit</a> in 2022, even though total farm income <a href="https://www.ers.usda.gov/topics/farm-economy/farm-sector-income-finances/highlights-from-the-farm-income-forecast">set a record at $162 billion</a>. Vilsack asserts that less-profitable operations should be the focus of this farm bill – but when pressed, he appears <a href="https://thehill.com/policy/equilibrium-sustainability/3903829-support-for-small-farms-wont-hurt-big-ones-vilsack-tells-lawmakers/">unwilling to concede</a> that support for large-scale operations should be changed in any way. </p>
<p>When I served as deputy secretary of agriculture from 2009 to 2011, I oversaw the department’s budget process and learned that investing in one thing often requires defunding another. My dream farm bill would invest in three priorities: <a href="https://www.nrdc.org/resources/grow-organic-climate-health-and-economic-case-expanding-organic-agriculture">organic agriculture as a climate solution</a>; infrastructure to support vibrant local and regional markets and shift away from an agricultural economy dependent on exporting low-value crops; and agricultural science and technology research aimed at reducing labor and <a href="https://theconversation.com/fertilizer-prices-are-soaring-and-thats-an-opportunity-to-promote-more-sustainable-ways-of-growing-crops-183418">chemical inputs</a> and providing new solutions for sustainable livestock production. </p>
<p>In my view, it is time for tough policy choices, and it won’t be possible to fund everything. Congress’ response will show whether it supports business as usual in agriculture, or a more diverse and sustainable U.S. farm system.</p><img src="https://counter.theconversation.com/content/202555/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Kathleen Merrigan is a former Deputy Secretary of the US Department of Agriculture</span></em></p>Even if you don’t live near farm country, you’ve got a stake in the upcoming farm bill – including what kind of farms your tax dollars support.Kathleen Merrigan, Executive Director, Swette Center for Sustainable Food Systems, Arizona State UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1998452023-03-09T13:40:14Z2023-03-09T13:40:14ZThe Biden administration has called for protecting mature US forests to slow climate change, but it’s still allowing them to be logged<figure><img src="https://images.theconversation.com/files/514058/original/file-20230307-20-4x3z0m.jpg?ixlib=rb-1.1.0&rect=20%2C15%2C3438%2C2286&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">An old-growth tree that was cut in Alaska's Tongass National Forest. </span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/news-photo/an-old-growth-tree-that-was-cut-is-seen-in-the-tongass-news-photo/1241027768">Salwan Georges/The Washington Post via Getty Images</a></span></figcaption></figure><p>Forests are critically important for slowing climate change. They remove huge quantities of carbon dioxide from the atmosphere – <a href="https://doi.org/10.5194/essd-14-4811-2022">30% of all fossil fuel emissions annually</a> – and store carbon in trees and soils. Old and mature forests are especially important: They handle droughts, storms and wildfires better than young trees, and they store more carbon.</p>
<p>In a 2022 executive order, President Joe Biden called for <a href="https://www.federalregister.gov/documents/2022/04/27/2022-09138/strengthening-the-nations-forests-communities-and-local-economies">conserving mature and old-growth forests</a> on federal lands. Recently Biden <a href="https://theconversation.com/biden-restores-roadless-protection-to-the-tongass-north-americas-largest-rainforest-164680">protected nearly half</a> of the Tongass National Forest in Alaska from road-building and logging. </p>
<p>The Biden administration is compiling an inventory of mature and old-growth forests on public lands that will support further conservation actions. But at the same time, federal agencies are initiating and implementing numerous <a href="https://www.climate-forests.org/_files/ugd/ae2fdb_b5a2315e3e8b42498b4c269730c3955a.pdf">logging projects</a> in mature and old forests without accounting for how these projects will affect climate change or forest species. </p>
<p>As scientists who have spent decades studying <a href="https://scholar.google.com/citations?user=J2KWqAoAAAAJ&hl=en">forest ecosystems</a> and <a href="https://www.researchgate.net/profile/William-Moomaw">climate change impacts</a>, we find that to effectively slow climate change, it is essential to increase carbon storage in these forests, not reduce it. A first step toward this goal would be to halt logging federal forests with relatively <a href="https://doi.org/10.1038/s43247-021-00326-0">high-biomass carbon per acre</a> until the Biden administration develops a plan for conserving them. </p>
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<h2>Balancing timber and climate change</h2>
<p>Many of the <a href="https://sgp.fas.org/crs/misc/R42346.pdf">640 million acres</a> that the federal government owns and manages are used for multiple purposes, including protecting biodiversity and water quality, recreation, mining, grazing and logging. Sometimes these uses conflict with one another. </p>
<p>Legal mandates to manage land for multiple uses do not explicitly mention climate change, and federal agencies <a href="https://doi.org/10.1002/ecs2.3286">have not consistently factored climate change science</a> into their plans. However, at the beginning of 2023, the White House <a href="https://www.whitehouse.gov/ceq/">Council on Environmental Quality</a> directed federal agencies to consider the effects of climate change when they <a href="https://www.federalregister.gov/documents/2023/01/09/2023-00158/national-environmental-policy-act-guidance-on-consideration-of-greenhouse-gas-emissions-and-climate">propose major federal actions</a> that significantly affect the environment. </p>
<p>Some logging projects fall into this category. But many large logging projects that affect thousands of acres have been <a href="https://www.law.cornell.edu/cfr/text/36/220.6">legally exempted</a> from such analysis.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/514055/original/file-20230307-2080-gczo6j.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Steep hills studded with evergreen trees and laced with narrow roads." src="https://images.theconversation.com/files/514055/original/file-20230307-2080-gczo6j.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/514055/original/file-20230307-2080-gczo6j.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/514055/original/file-20230307-2080-gczo6j.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/514055/original/file-20230307-2080-gczo6j.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/514055/original/file-20230307-2080-gczo6j.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/514055/original/file-20230307-2080-gczo6j.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/514055/original/file-20230307-2080-gczo6j.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">Logging roads crisscross steep logged slopes in Idaho’s Clearwater National Forest in 2019.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/news-photo/logging-roads-remaining-after-a-timber-sale-crisscross-news-photo/1189427245">Don & Melinda Crawford/Education Images/Universal Images Group via Getty Images</a></span>
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<h2>What’s lost when old trees are cut</h2>
<p>Most forests in the continental U.S. have been harvested multiple times. Today, fewer than 5% of these forests <a href="https://doi.org/10.2737/WO-GTR-97">are more than 100 years old</a>. Old, very large trees are the ones that hold the most carbon, and harvesting forests is the main driver of forest carbon loss. </p>
<p>For example, in Oregon’s national forests east of the Cascades crest, a 1990s policy formerly spared trees larger than 21 inches in diameter – but the rule was rolled back in 2021 so that large trees could be cut. A recent analysis found that these larger trees comprised just 3% of all trees in the six national forests, but <a href="https://doi.org/10.3389/ffgc.2020.594274">accounted for 42% of living tree carbon</a>. </p>
<p>In the Green Mountain National Forest in Vermont, federal officials have approved 40,000 acres of harvest since 2016, targeting many mature and old trees. One 14,270-acre area that was approved for harvest in 2019 contained <a href="https://www.climate-forests.org/_files/ugd/ae2fdb_b5a2315e3e8b42498b4c269730c3955a.pdf">more than 130 stands older than 100 years</a>. This project required the construction of 25 miles of logging roads, which <a href="https://doi.org/10.1007/s40725-016-0044-x">can have harmful effects</a>, including fragmenting forests, polluting streams and making forests more vulnerable to human-caused wildfires. </p>
<p>Canada is also allowing large, mature trees to be harvested. In British Columbia, mature forests that include old-growth trees historically absorbed more carbon than they released to the atmosphere, resulting in a net carbon sink annually. But since 2002, these tracts have emitted more carbon than they removed from the atmosphere, primarily because of logging, beetle attacks and wildfires. According to British Columbia’s greenhouse gas emissions inventory, these forests now <a href="https://www2.gov.bc.ca/gov/content/environment/climate-change/data/provincial-inventory">emit more carbon than the province’s energy sector</a>. </p>
<p>In eastern Canada, the Pacific Northwest and the southeastern U.S., timber companies have removed many old trees and replaced them with plantations that contain just one or two tree species. This shift has reduced the structural diversity of the <a href="https://www.sciencedirect.com/topics/agricultural-and-biological-sciences/forest-canopy">forest canopy</a> – the ecologically important layer formed by the crowns of trees – and the diversity of tree species. Losing old-forest habitat has also caused broad-scale <a href="https://doi.org/10.1038/s41559-022-01737-8">population declines</a> among many forest bird species in eastern Canada, and is likely having the same effect in the U.S.</p>
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<iframe width="440" height="260" src="https://www.youtube.com/embed/dLOG5jzvnow?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">This National Park Service video explains how a second-growth forest – one that has grown back after being logged – is less diverse and healthy than an old, mature forest.</span></figcaption>
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<h2>More harvesting releases more carbon</h2>
<p>One argument forest product companies make to support logging is that wood can be regrown, and it <a href="https://bellwetherfp.com/lets-get-some-things-straight-about-logging-and-the-environment/#">releases less carbon dioxide to the atmosphere</a> than other building materials. Such claims often make optimistic assumptions that overstate the carbon benefits of harvesting trees by <a href="http://dx.doi.org/10.1088/1748-9326/ab1e95">factors of 2 to 100</a>. </p>
<p>Some studies indicate that <a href="https://www.fs.usda.gov/features/thinning-forest-trees">thinning forests</a> by harvesting some trees and <a href="https://doi.org/10.1002/fee.1791">reintroducing low-intensity fires</a> can reduce the intensity of future wildfires, leaving more carbon stored in trees. But these studies don’t account for the <a href="https://doi.org/10.1186/s13021-016-0066-5">large amount of carbon</a> that is released to the atmosphere after trees are cut.</p>
<p>In a review published in 2019, we worked with colleagues to estimate how much carbon was contained in trees that were harvested in Washington, Oregon and California from 1900 through 2015, and what happened to it after the trees were logged. We calculated that just 19% of the harvested carbon was in long-lived wood products like timber in buildings. Another 16% was in landfills, and the remaining 65% was <a href="https://doi.org/10.1088/1748-9326/ab28bb">released into the atmosphere</a> as carbon dioxide.</p>
<p>In contrast, in 2011 the Australian state of Tasmania <a href="https://www.dcceew.gov.au/climate-change/publications/state-and-territory-greenhouse-gas-inventories">suspended logging on half of its old-growth forest area</a>. Within less than a decade, Tasmania was <a href="https://doi.org/10.1088/1748-9326/ac661b">storing more carbon than it released</a> because it was avoiding harvest emissions and the mature trees it saved were accumulating so much carbon.</p>
<p>In the U.S. Pacific Northwest, implementation of the 1994 <a href="https://www.fs.usda.gov/r6/reo/overview.php#">Northwest Forest Plan</a>, which the Clinton administration developed to protect endangered species in old-growth forests on public lands, significantly <a href="https://doi.org/10.1016/j.foreco.2014.11.023">increased carbon storage</a> over the next 17 years. In contrast, privately managed lands in the region accumulated virtually no additional carbon after accounting for losses from wildfire and harvesting.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/514062/original/file-20230307-2223-vtcifz.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Truck loaded with massive logs." src="https://images.theconversation.com/files/514062/original/file-20230307-2223-vtcifz.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/514062/original/file-20230307-2223-vtcifz.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=390&fit=crop&dpr=1 600w, https://images.theconversation.com/files/514062/original/file-20230307-2223-vtcifz.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=390&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/514062/original/file-20230307-2223-vtcifz.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=390&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/514062/original/file-20230307-2223-vtcifz.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=490&fit=crop&dpr=1 754w, https://images.theconversation.com/files/514062/original/file-20230307-2223-vtcifz.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=490&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/514062/original/file-20230307-2223-vtcifz.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=490&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 logging truck in the Pacific Northwest in 1954. Since 1600, 90% of the original forests in what is now the U.S. have been logged.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/news-photo/lumber-truck-pacific-northwest-usa-1950-news-photo/629442731">Universal History Archive via Getty Images</a></span>
</figcaption>
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<h2>The cheapest and simplest way to capture carbon</h2>
<p>President Biden has set a goal of reducing U.S. greenhouse gas emissions to <a href="https://www.whitehouse.gov/wp-content/uploads/2021/10/US-Long-Term-Strategy.pdf">net-zero by 2050</a> to avoid catastrophic climate change. To reach that goal, U.S. forests, lands and oceans will have to remove as much carbon dioxide from the atmosphere as the nation emits from fossil fuels, industry and agriculture. </p>
<p>In the western U.S., our research shows that protecting half of the mature carbon-dense forests in zones that are relatively less vulnerable to drought and fire could <a href="https://doi.org/10.1038/s43247-021-00326-0">triple carbon stocks and accumulation</a> on protected forests by 2050. A majority of these forests are on public lands.</p>
<p>The carbon dioxide that human activities are releasing into the atmosphere today will elevate global temperatures and raise sea levels <a href="https://doi.org/10.1073/pnas.0812721106">for 1,000 years or more</a>, unless societies can find ways to remove it. In its 2022 climate assessment report, the Intergovernmental Panel on Climate Change concluded that protecting existing natural forests was “<a href="https://www.ipcc.ch/report/ar6/wg2/downloads/report/IPCC_AR6_WGII_Chapter02.pdf">the highest priority for reducing greenhouse gas emissions</a>.” </p>
<p>Conserving forests is one of the lowest-cost options for managing carbon dioxide emissions, and it doesn’t require <a href="https://theconversation.com/why-the-oil-industrys-pivot-to-carbon-capture-and-storage-while-it-keeps-on-drilling-isnt-a-climate-change-solution-171791">expensive or complex energy-consuming technologies</a>. In our view, sufficient science exists to justify a moratorium on harvesting mature trees on federal lands so that these forests can keep performing their invaluable work.</p><img src="https://counter.theconversation.com/content/199845/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>William Moomaw receives funding from the Rockefeller Brothers Fund. He is affiliated with the Woodwell Climate Research Center and the Union of Concerned Scientists. Moomaw has been a lead author of five major Intergovernmental Panel on Climate Change (IPCC) reports.</span></em></p><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>Protecting old and mature trees is the simplest and least expensive way to pull carbon out of the atmosphere – but proposed logging projects threaten mature stands across the US.Beverly Law, Professor Emeritus of Global Change Biology and Terrestrial Systems Science, Oregon State UniversityWilliam Moomaw, Professor Emeritus of International Environmental Policy, Tufts UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1957342022-12-15T19:07:00Z2022-12-15T19:07:00ZDespite government delays, food waste recycling bins are coming to your kitchen sooner than you think<figure><img src="https://images.theconversation.com/files/500630/original/file-20221213-16-wtj1iu.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C4861%2C3230&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">Shutterstock</span></span></figcaption></figure><p>Only <a href="https://experience.arcgis.com/experience/e6b5c78e1dac47f88e7e475ffacfc49b">24% of local councils</a> in Australia separately collect household food organics and garden organics (FOGO) waste. Another 16% provide garden waste collection only. This limited progress has prompted the federal government to push back the <a href="https://www.dcceew.gov.au/environment/protection/waste/publications/national-waste-policy-action-plan">target date</a>, from <a href="https://www.abc.net.au/news/2022-12-01/food-waste-target-abandoned-by-federal-government-/101707458">2023 to 2030</a>, for all councils to collect food and garden waste separately from landfill waste. </p>
<p>Most food waste currently goes into red bins as mixed waste bound for landfills. Kerbside collection of organic waste will become a standard service for all residents in <a href="https://www.compostconnect.org/what-governments-in-australia-are-doing-to-support-composting/">New South Wales and Victoria by 2030</a>, for metropolitan residents in South Australia and Western Australia by 2025 and for Canberra residents by 2023. </p>
<p>To achieve these targets, effective policies and incentives will need to be put in place for councils or private waste management companies. They will have to build and operate the infrastructure needed to process FOGO waste, and will want to recoup their costs. </p>
<p>Happily, this waste has increasing value as a source of both high-quality compost and <a href="https://www.climatecouncil.org.au/resources/biogas-green-gas-renewable-gas/">biogas</a>, which can be used like natural gas. The markets for these products, with gas prices in particular soaring, should help drive widespread adoption earlier than 2030.</p>
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Read more:
<a href="https://theconversation.com/four-bins-might-help-but-to-solve-our-waste-crisis-we-need-a-strong-market-for-recycled-products-132440">Four bins might help, but to solve our waste crisis we need a strong market for recycled products</a>
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<p><div data-react-class="Tweet" data-react-props="{"tweetId":"1014743247560822785"}"></div></p>
<h2>Why collect this waste separately?</h2>
<p>The rationale for diverting organic waste from <a href="https://www.dcceew.gov.au/environment/protection/waste/publications/australian-landfill-capacities-future">increasingly limited</a> landfill space is clear. Collecting this waste separately reduces landfill impacts and costs, while delivering other environmental benefits. </p>
<p>Organic waste in a landfill will biodegrade slowly, eventually turning into biogas (methane and carbon dioxide). It can also produce organic acids that <a href="https://doi.org/10.1016/j.jhazmat.2015.07.065">dissolve and mobilise heavy metals</a>, creating a toxic hazard.</p>
<p>Modern landfills operate for decades. Waste is covered as it is placed, but only with soil until the landfill is full. Despite the use of multi-layer liners and impermeable final covers, these eventually deteriorate. In addition to harmful local environmental legacies of landfills, emissions of methane – a potent greenhouse gas – cause global harm. </p>
<p>In contrast, returning clean organic material to soils is beneficial. Australia’s arable soils are typically low in organic carbon, which needs to be <a href="https://www.aora.org.au/sites/default/files/uploaded-content/field_f_content_file/using-compost-to-build-and-maintain-soil-carbon-factsheet.pdf">regularly supplemented</a>. </p>
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<strong>
Read more:
<a href="https://theconversation.com/we-need-more-carbon-in-our-soil-to-help-australian-farmers-through-the-drought-102991">We need more carbon in our soil to help Australian farmers through the drought</a>
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<figure class="align-center ">
<img alt="Piles of discarded food" src="https://images.theconversation.com/files/500643/original/file-20221213-6751-8iqefp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/500643/original/file-20221213-6751-8iqefp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/500643/original/file-20221213-6751-8iqefp.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/500643/original/file-20221213-6751-8iqefp.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/500643/original/file-20221213-6751-8iqefp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/500643/original/file-20221213-6751-8iqefp.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/500643/original/file-20221213-6751-8iqefp.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">Food waste in landfill emits methane but it can instead be used to produce valuable compost and biogas.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<p>But, to produce high-quality compost, FOGO must be collected in a separate bin to avoid contamination. It’s possible to extract organic material from mixed (red bin) waste. This is done by grinding the waste and then using magnets, eddy currents, water flotation and air sorting to remove glass, plastic and metal fragments. </p>
<p>However, red bin waste is not closely monitored. It can contain batteries, electrical goods, paints and other sources of heavy metals in dissolved or fine-particle form. </p>
<p>This is why NSW banned the use on land of compost derived from mixed waste in 2019. A NSW <a href="https://www.epa.nsw.gov.au/-/media/epa/corporate-site/resources/recycling/mixed-waste-technical-committee-report.pdf">EPA review</a> had identified cadmium, zinc and copper as metals of high concern in this compost. It also found chemicals such as flame retardants and disinfectants were household sources of persistent organic pollutants. </p>
<h2>How much waste are we talking about?</h2>
<p>The size and composition of the FOGO resource will change if Australia achieves the UN Sustainable Development Goal of halving the food waste generated per person by 2030, compared to 2015. The <a href="https://www.dcceew.gov.au/environment/protection/waste/publications/national-waste-policy-action-plan">2019 National Waste Policy and Action Plan</a> adopted this goal. </p>
<p>Estimates of food waste in Australia vary. The most comprehensive survey was a nation-wide audit in 2020 of <a href="https://fightfoodwastecrc.com.au/wp-content/uploads/2021/06/kerbside_bin_audits.pdf">450 kerbside bins</a> by the <a href="https://fightfoodwastecrc.com.au/">Fight Food Waste Cooperative Research Centre</a>. It showed weekly food waste was 0.79kg per person, including 0.34kg of inedible peels, bones and expired or perished food. These households disposed of a similar amount of food waste in the home by composting, feeding to pets or flushing down the sink. </p>
<p>The United Nations Environment Programme’s <a href="https://www.unep.org/resources/report/unep-food-waste-index-report-2021">2021 estimate</a> is similar at 1.5-1.7kg of weekly food waste per person. The <a href="https://www.dcceew.gov.au/environment/protection/waste/national-waste-reports/2020">National Waste Database</a> estimate for Australia is higher at 2.37kg. </p>
<p>According to the database, 31% of food waste in NSW was separately collected and composted or digested in 2018-19. The figure was less than 10% in all other states except Western Australia, where it was 13%. </p>
<p>As for garden waste, <a href="https://www.dcceew.gov.au/environment/protection/waste/national-waste-reports/2020">2.01kg per person each week</a> goes into kerbside bins. Over 50% of garden waste (85% in South Australia) is separately collected in all mainland states. </p>
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Read more:
<a href="https://theconversation.com/why-best-before-food-labelling-is-not-best-for-the-planet-or-your-budget-189686">Why 'best before' food labelling is not best for the planet or your budget</a>
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<h2>How can collection costs be covered?</h2>
<p>The <a href="https://www.aora.org.au/sites/default/files/uploaded-content/field_f_content_file/using-compost-to-build-and-maintain-soil-carbon-factsheet.pdf">demand for organic carbon</a> in Australian soils <a href="https://mraconsulting.com.au/getting-the-most-out-of-the-fogo-revolution/">far exceeds</a> the amount of compost that could be produced from FOGO. But, to tap into this market, the compost quality must be consistent. </p>
<p>A clear definition of acceptable FOGO and carefully controlled operations are needed to produce consistent quality compost. The <a href="https://mraconsulting.com.au/kerbside-fogo-needs-a-national-standard/">waste management industry</a> and <a href="https://www.agriculture.gov.au/sites/default/files/documents/recycled-organics-in-australia-review-regulations-standards-final-report.pdf">advice to government</a> have called for FOGO bins to be limited to food waste and garden waste, excluding materials like paper, cardboard and animal waste. </p>
<p>Many councils compost garden waste on open pads, some under cover. Machinery is used to shred and turn over the piles to control temperature and moisture levels. </p>
<p>The control of this process becomes more critical for FOGO. Food waste can be smelly, particularly if the composting process is open to the air but not adequately aerated. </p>
<p>Tighter control, particularly of odour, can be achieved if composting is done in vessels. Typically, these take the form of <a href="https://www.phoenixpower.com.au/">concrete tunnels</a>. </p>
<p>High-quality compost for farming can fetch <a href="https://www.soilwealth.com.au/imagesDB/news/ICP_SW_Composteconomics_v3.pdf">A$50 to $80 per cubic metre</a>. That makes separate collection and processing of bio-waste more attractive financially. </p>
<p>In addition, surging gas and electricity prices and the revival in value of renewable energy credits have increased the viability of first anaerobically digesting FOGO to produce biogas, then composting the digested material. FOGO can be digested in sealed tunnels similar to composting tunnels. </p>
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Read more:
<a href="https://theconversation.com/capturing-the-true-wealth-of-australias-waste-82644">Capturing the true wealth of Australia’s waste</a>
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<p>This biogas will not solve Australia’s gas shortage (FOGO biogas could meet about 2% of the demand). However, I calculate, as a conservative figure, that the income to an anaerobic digestion operator would exceed $40 per fresh tonne of waste. This figure is based on a conservative methane yield of 50m³ per tonne, a wholesale electricity price of $200 per MWhr and a renewable energy credit value of $50 per MWhr.</p>
<p>All of these considerations indicate we should be confident almost all households will have a FOGO service before 2030. The alternative is to waste this resource in landfills, with all their future environmental liabilities.</p><img src="https://counter.theconversation.com/content/195734/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>William Clarke has received funding from the Australian Research Council on projects related to the degradation of organic wastes in landfills and in anaerobic digesters. He has also performed numerous consulting projects assessing the biogas yields from various organic wastes. </span></em></p>Most food waste still goes into red bins of mixed waste bound for landfill. It’s using up precious landfill space and harming the environment when it could produce valuable compost and biogas instead.William Clarke, Professor of Waste Management, The University of QueenslandLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1877842022-09-21T02:48:54Z2022-09-21T02:48:54ZWe helped fill a major climate change knowledge gap, thanks to 130,000-year-old sediment in Sydney lakes<figure><img src="https://images.theconversation.com/files/482252/original/file-20220901-23-79mmzt.jpg?ixlib=rb-1.1.0&rect=0%2C3%2C2492%2C1641&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Lake Couridjah, Thirlmere Lakes National Park in New South Wales</span> <span class="attribution"><span class="source">Shutterstock</span></span></figcaption></figure><p>Plants capture <a href="https://earthobservatory.nasa.gov/features/CarbonCycle">around half</a> the carbon we emit by burning fossil fuels, making them a crucial part of mitigating climate change. But carbon is often released back into the atmosphere when plants die, decompose and eventually turn into dirt.</p>
<p>Carbon is only permanently removed from the atmosphere if it’s stored in sediments that accumulate at the bottom of oceans, lakes, reservoirs, or in peat bogs. </p>
<p><a href="https://www.sciencedirect.com/science/article/pii/S0921818122001898">Our latest research</a> on the Thirlmere Lakes near Sydney aimed to find out how trees, shrubs and soils in Australia’s eastern tablelands responded to climate changes over the last 130,000 years. The key question we sought to answer was whether carbon stored in Australia’s trees, shrubs, and soils contribute to the pool of carbon stored safely in lake sediment. </p>
<p>The answer, we determined, depends on a number of crucial factors, and erosion plays an essential, previously neglected, part. </p>
<p>Erosion is like a conveyer belt for carbon – it transports carbon to the lake from nearby hills where plants die. We found when the climate near Sydney was warm and wet, then trees and shrubs flourished and erosion was reduced. So while more carbon was stored in plants, it took longer for carbon in soil to be safely buried in the lake. </p>
<p>Previous research has shown ignoring the impact of erosion on carbon burial has caused Australia to overestimate the amount of <a href="https://www.nature.com/articles/nclimate2829">carbon</a> emitted into the atmosphere over the last 50 years, by a staggering 40%. </p>
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Read more:
<a href="https://theconversation.com/dig-this-a-tiny-echidna-moves-8-trailer-loads-of-soil-a-year-helping-tackle-climate-change-155947">Dig this: a tiny echidna moves 8 trailer-loads of soil a year, helping tackle climate change</a>
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<h2>The cycle of carbon</h2>
<p>Plants capture carbon dioxide from the atmosphere during photosynthesis, and store carbon in their tissue. So what happens when plants die? </p>
<p>The equation is easier for the oceans: dead <a href="https://oceanservice.noaa.gov/facts/phyto.html">phytoplankton</a> (tiny algae floating close to the surface) sinks to seafloor, where most of its captured carbon is stored safely far away from the atmosphere. On land things are more complex.</p>
<p>When trees and shrubs die, they cover the surface, decompose and become part of the soil. In fact, <a href="https://www.sciencedirect.com/science/article/pii/S0012825215300817">80%</a> of carbon on land is stored in soils. Decomposition releases some of the captured carbon back into the atmosphere, unless they’re buried deep. </p>
<p>In Australia, much more carbon is stored when weather conditions are wetter. During the strong La Niña event of 2010-2012, large areas of the Australia’s dry interior and temperate landscape experienced significant “greening”. </p>
<p>Research <a href="https://www.nature.com/articles/srep23113">shows 20%</a> more carbon was captured from the Earth’s atmosphere during this La-Niña event due to increasing plant growth. Australia contributed <a href="https://www.nature.com/articles/nature13376">more than half</a> of this.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/482253/original/file-20220901-19-ajx6ox.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/482253/original/file-20220901-19-ajx6ox.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/482253/original/file-20220901-19-ajx6ox.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/482253/original/file-20220901-19-ajx6ox.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/482253/original/file-20220901-19-ajx6ox.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/482253/original/file-20220901-19-ajx6ox.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/482253/original/file-20220901-19-ajx6ox.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/482253/original/file-20220901-19-ajx6ox.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">The Thirlmere Lakes during dry conditions.</span>
<span class="attribution"><span class="source">Timothy J. Cohen</span>, <span class="license">Author provided</span></span>
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</figure>
<h2>The last 130,000 years</h2>
<p>The story is even more dramatic if you look back at the last 130,000 years. During this time, the planet experienced cycles of two climate phenomena: glacial periods and interglacial periods. </p>
<p>A “glacial” period is characterised by much colder and drier conditions, when wide parts of northern Europe, Eurasia, and America were covered by ice kilometres thick. The last time it peaked was around 21,000 years ago.</p>
<p>Australia endured warmer and wetter conditions during “interglacial” periods, which peaked around 125,000 years ago and again over the last 11,600 years.</p>
<p>For our research, we drilled deep into Sydney’s Thirlmere Lake mud, and pulled up long columns of sediment containing traces of vegetation, climate, and erosion from the last 130,000 years. We observed significant changes in the types of vegetation growing in the catchment over this time.</p>
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Read more:
<a href="https://theconversation.com/soil-abounds-with-life-and-supports-all-life-above-it-but-australian-soils-need-urgent-repair-187280">Soil abounds with life – and supports all life above it. But Australian soils need urgent repair</a>
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<p>Shrubs and large trees such as eucalypts flourished during warmer and wetter interglacial periods. They were less abundant when it was colder and dry during glacial periods, when grass and herbs became more common.</p>
<p>Large trees <a href="https://besjournals.onlinelibrary.wiley.com/doi/10.1111/j.1365-2664.2006.01221.x">capture more</a> carbon dioxide from the atmosphere than grasses and herbs. And this captured carbon then accumulates in the surface of soils when the plant dies. </p>
<p>But how is the soil-carbon transported from the slopes where the trees and shrubs grow, to the bottom of the lake?</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/482254/original/file-20220901-809-84vlza.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/482254/original/file-20220901-809-84vlza.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/482254/original/file-20220901-809-84vlza.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=294&fit=crop&dpr=1 600w, https://images.theconversation.com/files/482254/original/file-20220901-809-84vlza.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=294&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/482254/original/file-20220901-809-84vlza.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=294&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/482254/original/file-20220901-809-84vlza.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=370&fit=crop&dpr=1 754w, https://images.theconversation.com/files/482254/original/file-20220901-809-84vlza.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=370&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/482254/original/file-20220901-809-84vlza.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=370&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Extracting sediment cores from a lake.</span>
<span class="attribution"><span class="source">Fabian Boesl</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<h2>Soil erosion</h2>
<p>Erosion – whether gravity, water or wind - forms our landscape and is essential for the accumulation of soil carbon in lakes, reservoirs and the oceans.</p>
<p>The deeper the carbon is buried in the sediments of these reservoirs, the more efficiently it is locked away from the atmosphere. In contrast, the longer it remains on the slopes and in soils close to the surface, the more it decomposes, and carbon dioxide is released back into the atmosphere.</p>
<p>For the wider Sydney region, more plant growth occurred during the interglacial period, which take up vast amounts of carbon dioxide from the atmosphere. But this may be offset by decreased erosion. And indeed, our data suggests decreased erosion during interglacial periods. </p>
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<em>
<strong>
Read more:
<a href="https://theconversation.com/65-000-years-of-food-scraps-found-at-kakadu-tell-a-story-of-resilience-amid-changing-climate-sea-levels-and-vegetation-181240">65,000 years of food scraps found at Kakadu tell a story of resilience amid changing climate, sea levels and vegetation</a>
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<p>This decreased erosion is because of the protection of trees which, for example, stabilise the soil with their roots. Indeed, we found tree cover slows the rate that soil carbon moves from slope to lake by nearly 10 times. </p>
<p>This means there’s much more time for soils to decompose on the slope, and to release carbon back into the atmosphere.</p>
<p>Nevertheless, we still recorded significantly higher carbon storage in lake sediments during warmer and wetter periods, thanks largely to the greater growth of trees and shrubs compared to grasses, which are more abundant during interglacial periods. This compensates for the reduced erosion. </p>
<p>We also found the lake transformed into a productive wetland during warm periods. This means more carbon is also captured by plants growing in the lake.</p>
<h2>What will happen under climate change?</h2>
<p>The interplay between climate, vegetation, and erosion is difficult to quantify. Our research fills a critical gap in knowledge, as climate models currently don’t account for soil-carbon erosion. </p>
<p>Those models assume all soil-carbon is eventually emitted back into the atmosphere, introducing uncertainties into climate predictions. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/482255/original/file-20220901-27-wp7dvb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/482255/original/file-20220901-27-wp7dvb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/482255/original/file-20220901-27-wp7dvb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=338&fit=crop&dpr=1 600w, https://images.theconversation.com/files/482255/original/file-20220901-27-wp7dvb.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=338&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/482255/original/file-20220901-27-wp7dvb.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=338&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/482255/original/file-20220901-27-wp7dvb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=424&fit=crop&dpr=1 754w, https://images.theconversation.com/files/482255/original/file-20220901-27-wp7dvb.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=424&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/482255/original/file-20220901-27-wp7dvb.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=424&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">The Thirlmere Lakes during wet conditions.</span>
<span class="attribution"><span class="source">Fabian Boesl</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>Future climate change may raise the risk of the <a href="https://www.environment.nsw.gov.au/research-and-publications/our-science-and-research/our-research/water/freshwater-and-wetlands/thirlmere-lakes-research">Thirlmere Lakes</a> drying out, which means the sediments will be exposed, which promotes decomposition. This means the previously stored carbon will be emitted back into the atmosphere as carbon dioxide.</p>
<p>Extreme aridity may also reduce terrestrial plant growth, as it did during the millennium drought. </p>
<p>Further, destruction of vegetation by <a href="https://theconversation.com/australian-forests-will-store-less-carbon-as-climate-change-worsens-and-severe-fires-become-more-common-173233">severe bushfires</a> reduce biomass yield to the wetlands. Preserving Australia’s unique native terrestrial vegetation and wetlands is therefore essential to sustain the continent’s role in the global carbon cycle.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/australian-forests-will-store-less-carbon-as-climate-change-worsens-and-severe-fires-become-more-common-173233">Australian forests will store less carbon as climate change worsens and severe fires become more common</a>
</strong>
</em>
</p>
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<img src="https://counter.theconversation.com/content/187784/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>The research at the Thirlmere Lakes was funded by the NSW Department of Environment and Heritage and commenced following community concerns that nearby mining was affecting the hydrology of the lakes and the Friends of Thirlmere Community group continues to advocate for the protection and enjoyment of the area. The authors gratefully acknowledge the contributions of Matthew Forbes to this article. We acknowledge the contribution of the Aboriginal people of the area who are the first custodians of Country.
Alexander Francke receives funding from the Australian Research Council.
</span></em></p><p class="fine-print"><em><span>Anthony Dosseto receives funding from the Australian Research Council. </span></em></p><p class="fine-print"><em><span>Haidee Cadd receives funding from The Australian Research Council.</span></em></p><p class="fine-print"><em><span>Tim Cohen has received funding from the Australian Research Council (ARC); ARC Centre of Excellence Scheme (Project Number CE170100015) and ARC Future Fellowship (FT180100524) and NSW OEH Thirlmere lakes Research Program</span></em></p>80% of carbon on land in stored in soil. Our new research investigated how erosion transports this carbon to the bottom of lakes, where it’ll never be released into the atmosphere.Alexander Francke, Research Fellow, University of AdelaideAnthony Dosseto, Professor, University of WollongongHaidee Cadd, Research associate, University of WollongongTim Cohen, Associate Professor and ARC Future Fellow, University of WollongongLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1775052022-04-12T12:14:50Z2022-04-12T12:14:50ZRaising cattle on native grasses in the eastern U.S. benefits farmers, wildlife and the soil<figure><img src="https://images.theconversation.com/files/455415/original/file-20220331-18-we7ab1.jpg?ixlib=rb-1.1.0&rect=0%2C10%2C2297%2C1714&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Native grasses, long overlooked, have been shown to benefit cattle and diverse native animals. </span> <span class="attribution"><span class="source">Patrick Keyser</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span></figcaption></figure><p>Early on a cool June morning, heavy dew lies on the grass of rolling farm country somewhere in Tennessee, or Missouri, or Pennsylvania. Small patches of fog hang in low lying pockets of these fields. In the distance, hardworking farmers are starting their day. Farm equipment clangs, tractors roar to life and voices lining out the day’s work drift on the air.</p>
<p>This pastoral scene is repeated thousands of times each morning across rural America. But something is missing: the exuberant “Bob bob white!” call of the bobwhite quail that for generations was the soundtrack to summer mornings. Once abundant across the eastern U.S., bobwhite populations <a href="https://www.allaboutbirds.org/guide/Northern_Bobwhite/lifehistory">have declined by 85%</a>. <a href="https://www.usgs.gov/centers/eesc/science/north-american-breeding-bird-survey#data">Calculations</a> suggest that the remaining population could be cut in half within the next decade.</p>
<iframe width="100%" height="360" src="https://macaulaylibrary.org/asset/63289481/embed/640" frameborder="0" allowfullscreen="" style="width:640px;"></iframe>
<p>Many other grassland birds, such as <a href="https://www.allaboutbirds.org/guide/grasshopper_sparrow">grasshopper sparrows</a> and <a href="https://www.allaboutbirds.org/guide/Eastern_Meadowlark/id">eastern meadowlarks</a>, also are <a href="https://doi.org/10.1126/science.aaw1313">disappearing at an alarming rate</a>. Taken together, grassland birds have experienced the worst population declines among all North American birds.</p>
<p>Why is this happening? In a word, habitat. Native grasslands in the U.S., especially those east of the Great Plains, which once covered millions of acres, <a href="https://www.nbcnews.com/science/environment/efforts-afoot-souths-disappearing-grasslands-rcna128">have almost completely disappeared</a>. Some have been converted to croplands. Others have been allowed to grow back up into forests, where shade from the tree canopy prevents the growth of these grasses. </p>
<p>Still others have been planted with grasses that are native to Europe, Africa or Asia. These introduced grasses tend to be shorter than our tall, native species and grow in dense, solid mats that cover the ground. Native species, on the other hand, are <a href="https://workbasedlearning.pnnl.gov/pals/resource/cards/bunchgrass.stm">bunchgrasses</a>: They grow in clumps, with spaces between plants that benefit many of these nesting birds, especially the bobwhite.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/455418/original/file-20220331-18-pw0015.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/455418/original/file-20220331-18-pw0015.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/455418/original/file-20220331-18-pw0015.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/455418/original/file-20220331-18-pw0015.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/455418/original/file-20220331-18-pw0015.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/455418/original/file-20220331-18-pw0015.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/455418/original/file-20220331-18-pw0015.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">A bobwhite quail nest nestles in a bunch of switchgrass, a native grass species also valuable for cattle forage.</span>
<span class="attribution"><span class="source">David Peters</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<h2>Native grasses for birds, and cattle</h2>
<p>One solution to these declines draws on the concept of working lands conservation – making agricultural lands productive not only for cattle, but <a href="https://doi.org/10.1002/wsb.1000">also for declining species such as grassland birds</a>. One compelling opportunity for such an approach is using some of the native grasses that have been lost from the eastern U.S. to provide pasture for cattle. Reintroducing these grasses to farms could benefit cattle farmers as well as birds. My new book, “<a href="https://nativegrasses.tennessee.edu/native-grass-forages/">"Native Grass Forages for the Eastern U.S.</a>,” explains why and how these grasses can fit into working farms. </p>
<p>I have combined my research on native grasses over the past 15 years at the <a href="https://utia.tennessee.edu/">University of Tennessee Institute of Agriculture</a> with the work of many other scientists that has accumulated over the past 100 years. Collectively, this research suggests that native grasses can not only be brought back but can play a strategic role on our farms today.</p>
<p>Growing forages requires fertilizer, diesel and seed, all of which are becoming more expensive. At the same time, climate change is making <a href="https://www.nytimes.com/2021/08/25/climate/nyt-climate-newsletter-drought-floods.html">some parts of the U.S. wetter and other parts drier</a>. </p>
<p>In the face of these stresses, I see native grasses like <a href="https://plants.usda.gov/DocumentLibrary/factsheet/pdf/fs_ange.pdf">big bluestem</a> as a promising solution. These grasses, which have grown in North America for millennia, are naturally well adapted to the eastern U.S., and I believe they can once again benefit family farms.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/zOopOzbXGYk?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Patrick Keyser interviews Brad Black of Color Wheel Farm in Monroe County, Tennessee, on his experience planting a native grass, switchgrass.</span></figcaption>
</figure>
<p>As I show in my book, these grasses have roots that can extend as much as 8 to 10 feet deep into the soil. They are remarkably drought tolerant and can grow and thrive in soils with low fertility and high acidity. </p>
<p>Their large root systems also help to increase the organic matter in soils, which makes the soil healthier and more productive. Building up organic matter, which consists mostly of carbon, stores carbon in the soil rather than the atmosphere. </p>
<p>But what about the cattle? Numerous studies show that forage yields are high for these species. <a href="https://doi.org/10.15232/S1080-7446(15)30251-5">Cattle readily consume them</a>, and this diet produces strong gains on the growing animals. This combination of high yields, strong gains and low input requirements means that these forages <a href="https://doi.org/10.1002/agj2.20032">can be produced profitably</a>.</p>
<p>A recent study conducted here in Tennessee resulted in <a href="https://doi.org/10.1002/agj2.20426">strong animal performance for beef steers and heifers</a>, with the cost of feed for the animals coming in at only $0.29 per pound. This is a very good bargain: Cost ranges for many nonnative forages can be $0.80-0.90 per pound, and purchased feed can run <a href="https://doi.org/10.3168/jds.2015-9475">well over $2.00 per pound of weight gain</a>.</p>
<p>In that same study, we monitored the nesting success of two at-risk species associated with eastern pastures: grasshopper sparrows and field sparrows. We found that compared to pastures growing a nonnative grass species called tall fescue, the native grass pastures produced between two and six times more fledgling birds per acre. This is the outcome that working lands conservation seeks to deliver: more beef and more birds, all at a fair price.</p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/455416/original/file-20220331-21-urolii.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/455416/original/file-20220331-21-urolii.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/455416/original/file-20220331-21-urolii.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=800&fit=crop&dpr=1 600w, https://images.theconversation.com/files/455416/original/file-20220331-21-urolii.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=800&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/455416/original/file-20220331-21-urolii.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=800&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/455416/original/file-20220331-21-urolii.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1005&fit=crop&dpr=1 754w, https://images.theconversation.com/files/455416/original/file-20220331-21-urolii.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1005&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/455416/original/file-20220331-21-urolii.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1005&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Scientists track the movements of this male bobwhite quail, here about to be released into the wild, through a radio transmitter covered by a tuft of feathers beneath the bird’s chin.</span>
<span class="attribution"><span class="source">Ross Ketron</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<h2>Making the switch</h2>
<p>The biggest challenge of cultivating native grasses is getting the grasses established. Converting existing pastures to native grasses requires completely renovating the fields, and lots of patience as the native grass seedlings develop. These species are slow starters. </p>
<p>Once they get a good root system under them, they can grow quite rapidly, but until then they are vulnerable to weed pressure. And converting fields is not cheap, due particularly to seed costs. However, farmers can receive financial support for planting native grasses from the U.S. Department of Agriculture’s <a href="https://www.nrcs.usda.gov/wps/portal/nrcs/main/national/programs/">Natural Resources Conservation Service</a>. </p>
<p>[<em>Over 150,000 readers rely on The Conversation’s newsletters to understand the world.</em> <a href="https://memberservices.theconversation.com/newsletters/?source=inline-150ksignup">Sign up today</a>.]</p>
<p>As the world’s population grows, it will be a struggle to produce enough nutrient-dense proteins to feed everyone. Grasslands can produce high-quality dietary protein cost-effectively, while also reducing atmospheric carbon and supporting North American grassland birds and other wild species. </p>
<p>As King Solomon said long ago, <a href="http://web.mit.edu/jywang/www/cef/Bible/NIV/NIV_Bible/ECC+1.html#:%7E:text=The%20eye%20never%20has%20enough,nothing%20new%20under%20the%20sun.">there is nothing new under the sun</a>. Native grasses are not new, but today I see them as a modern solution to some of our planet’s most pressing challenges.</p><img src="https://counter.theconversation.com/content/177505/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Patrick Keyser has received funding from the US Department of Agriculture, the University of Tennessee Institute of Agriculture, private donors, the Kentucky Department of Fish and Wildlife Resources, and the Tennessee Wildlife Resources Agency.
</span></em></p>Growing native grasses as cattle forage is an example of working lands conservation – balancing human use of the land with conservation goals.Patrick Keyser, Professor of Forestry, Wildlife and Fisheries and Director, Center for Native Grasslands Management, University of TennesseeLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1685452022-01-20T13:44:50Z2022-01-20T13:44:50ZBeavers offer lessons about managing water in a changing climate, whether the challenge is drought or floods<figure><img src="https://images.theconversation.com/files/440331/original/file-20220111-21389-ltiaq3.jpeg?ixlib=rb-1.1.0&rect=18%2C18%2C4007%2C2999&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Wetlands created by beavers, like this one in Amherst, Massachusetts, store floodwaters and provide habitat for animals and birds.</span> <span class="attribution"><span class="source">Christine Hatch</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span></figcaption></figure><p>It’s no accident that both the <a href="https://web.mit.edu/graphicidentity/tim-the-beaver.html">Massachusetts Institute of Technology</a> and the <a href="https://identity.caltech.edu/logoseal/athletics">California Institute of Technology</a> claim the beaver (<em>Castor canadensis</em>) as their mascots. Renowned engineers, beavers seem able to dam any stream, building structures with logs and mud that can flood large areas. </p>
<p>As climate change causes extreme storms in some areas and intense drought in others, scientists are finding that beavers’ small-scale natural interventions <a href="https://www.chelseagreen.com/product/eager-paperback/">are valuable</a>. In dry areas, beaver ponds restore moisture to the soil; in wet zones, their dams and ponds can help to slow floodwaters. These ecological services are so useful that land managers are translocating beavers <a href="https://www.theguardian.com/environment/2021/feb/23/beavers-native-american-tribes-washington-california">in the U.S.</a> and <a href="https://www.bbc.com/future/article/20210713-the-beavers-returning-to-the-desert">the United Kingdom</a> to help restore ecosystems and make them more resilient to climate change. </p>
<p>Scientists estimate that <a href="https://doi.org/10.1088/1748-9326/abd34e">hundreds of millions of beavers</a> once dammed waterways across the Northern Hemisphere. They were <a href="https://ecwpress.com/products/once-they-were-hats">hunted nearly to extinction for their fur</a> in the 18th and 19th centuries in Europe and North America but are <a href="https://www.nationalgeographic.com/animals/article/beavers-climate-change-conservation-news">making comebacks today</a> in many areas. As a <a href="https://www.researchgate.net/profile/C-Hatch">geoscientist specializing in water resources</a>, I think it’s important to understand how helpful beavers can be in the <a href="https://methowbeaverproject.org">right places</a> and to find ways for humans to coexist with them in developed areas.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/6lT5W32xRN4?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Scientists are studying ways to use beavers to mitigate wildfire and drought risks in the western U.S.</span></figcaption>
</figure>
<h2>How beavers alter landscapes</h2>
<p>Beavers <a href="https://www.sciencefocus.com/nature/why-do-beavers-build-dams/">dam streams to create ponds</a>, where they can construct their dome-shaped lodges in the water, keeping predators at a distance. When they create a pond, many other effects follow. </p>
<p>Newly flooded trees die but remain standing as bare “snags” where birds nest. The diverted streams create complicated interwoven channels of slow-moving water, tangled with logs and plants that provide hiding places for fish. The messy complexity behind a beaver dam creates many different kinds of habitats for creatures such as fish, birds, frogs and insects. </p>
<p>Human dams often <a href="https://www.nwcouncil.org/reports/columbia-river-history/fishpassage">block fish passage</a> upstream and downstream, even when the dams <a href="https://www.scientificamerican.com/article/upstream-battle-fishes-shun-modern-dam-passages-population-declines/">include fish ladders</a>. But <a href="https://doi.org/10.1111/j.1467-2979.2011.00421.x">studies have shown</a> that fish have no trouble migrating upstream past beaver dams. One reason may be that the fish can rest in slow pools and cool pond complexes after navigating the tallest parts of the dams. </p>
<p>The slow-moving water behind beaver dams is very effective at trapping sediment, which drops to the bottom of the pond. Studies measuring total organic carbon in active and abandoned beaver meadows suggest that before the 1800s, active and abandoned beaver ponds across North America <a href="https://doi.org/10.1002/grl.50710">stored large amounts of carbon</a> in sediment trapped behind them. This finding is relevant today as scientists look for ways to <a href="https://theconversation.com/what-the-world-needs-now-to-fight-climate-change-more-swamps-99198">increase carbon storage in forests and other natural ecosystems</a>.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/441410/original/file-20220118-15-d1qkya.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Curved dam in a marsh, made of wood, grass and mud." src="https://images.theconversation.com/files/441410/original/file-20220118-15-d1qkya.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/441410/original/file-20220118-15-d1qkya.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/441410/original/file-20220118-15-d1qkya.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/441410/original/file-20220118-15-d1qkya.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/441410/original/file-20220118-15-d1qkya.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=502&fit=crop&dpr=1 754w, https://images.theconversation.com/files/441410/original/file-20220118-15-d1qkya.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=502&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/441410/original/file-20220118-15-d1qkya.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=502&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">A beaver dam in Mason Neck State Park in Lorton, Virginia, creates a pond behind it that can spread out and slow down floodwaters during a storm.</span>
<span class="attribution"><a class="source" href="https://flic.kr/p/BDNqd1">Virginia State Parks</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<p>Beavers may persist in one location for decades if they aren’t threatened by bears, cougars or humans, but they will move on if food runs out near their pond. When abandoned beaver dams fail, the ponds drain and gradually become grassy meadows as plants from the surrounding land seed them. </p>
<p>Dried meadows can serve as floodplains for nearby rivers, allowing waters to spill out and provide forage and spawning areas for fish during high flows. Floodplain meadows are <a href="https://www.fws.gov/oregonfwo/toolsforlandowners/riverscience/documents/brg%20v.1.0%20final%20reduced.pdf">valuable habitat</a> for ground-nesting birds and other species that depend on the river. </p>
<h2>The value of slowing the flow</h2>
<p>As human settlements expand, people often wish to make use of every acre. That typically means that they want either land that is solid and dry enough to farm or waterways they can navigate by boat. To create those conditions, humans remove floating logs from streams and install drains to draw water off of fields and roads as quickly and efficiently as possible. </p>
<p>But covering more and more land surface with barriers that don’t absorb water, such as pavement and rooftops, means that water flows into rivers and streams more quickly. Rainfall from an average storm can produce an intense river flow that <a href="https://extension.umass.edu/riversmart/">erodes the banks and beds of waterways</a>. And as climate change <a href="https://royalsociety.org/topics-policy/projects/climate-change-evidence-causes/question-13/">fuels more intense storms in many places</a>, it will amplify this destructive impact.</p>
<p>Some developers limit this kind of damaging flow by using <a href="https://basc.pnnl.gov/resource-guides/swales-drains-and-site-grading-stormwater-control">nature-based engineering principles</a>, such as “ponding” water to intercept it and slow it down; spreading flows out more widely to reduce the water’s speed; and designing swales, or sunken spots, that allow water to sink into the ground. Beaver wetlands do all of these things, only better. Research in the United Kingdom has documented that beaver activity can <a href="https://doi.org/10.1016/j.scitotenv.2016.10.122">reduce the flow of floodwaters from farmlands by up to 30%</a>. </p>
<p><div data-react-class="Tweet" data-react-props="{"tweetId":"1443636906487697416"}"></div></p>
<p>Beaver meadows and wetlands also <a href="https://kingcounty.gov/services/environment/animals-and-plants/beavers/Benefits.aspx">help cool the ground around and beneath them</a>. Wet soil in these zones contains a lot of organic matter from buried and decayed plants, which holds onto moisture longer than soil formed only from rocks and minerals. In my <a href="https://www.livingobservatory.org/learning-report">wetland research</a>, I have found that after a storm, water entering the ground passes through pure mineral sand in hours to days but can remain in soils that are 80%-90% organic matter for as long as a month. </p>
<p>Cool, wet soil also serves as a buffer against wildfires. Recent studies in the western U.S. have found that vegetation in beaver-dammed river corridors is <a href="https://doi.org/10.1002/eap.2225">more fire-resistant</a> than in areas without beavers because it is well watered and lush, so it doesn’t burn as easily. As a result, areas near beaver dams provide <a href="https://www.sagegrouseinitiative.com/beaver-breaks-how-beavers-and-low-tech-riparian-restoration-help-reduce-impacts-from-fire/">temporary refuge for wildlife</a> when <a href="https://doi.org/10.1002/bes2.1795">surrounding areas burn</a>.</p>
<h2>Making room for beavers</h2>
<p>The ecological services that beavers provide are most valuable in zones where nobody minds if the landscape changes. But in the densely developed eastern U.S., where I work, it’s hard to find open areas where beaver ponds can spread out without flooding ditches or roads. Beavers also topple expensive landscaped trees and will feed on some cultivated crops, such as <a href="https://agrilife.org/txwildlifeservices/files/2016/07/fs_beaver.pdf">corn and soybeans</a>.</p>
<p>Beavers are frequently blamed for flooding in developed areas, even though <a href="https://www.gazettenet.com/earth-matters-are-beavers-to-blame-for-flooding-damage-41825413">the real problem often is road design, not beaver dams</a>. In such cases, removing the beavers doesn’t solve the problem. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/440340/original/file-20220111-19-svgy1g.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Pipe in the middle of a flooded rural road" src="https://images.theconversation.com/files/440340/original/file-20220111-19-svgy1g.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/440340/original/file-20220111-19-svgy1g.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/440340/original/file-20220111-19-svgy1g.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/440340/original/file-20220111-19-svgy1g.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/440340/original/file-20220111-19-svgy1g.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/440340/original/file-20220111-19-svgy1g.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/440340/original/file-20220111-19-svgy1g.jpeg?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>
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<span class="caption">Debris carried by intense rains in July 2021 overtopped a beaver dam (still standing in the background) and washed out this undersized 3-foot culvert in western Massachusetts. It has since been replaced by a more resilient 9-foot structure.</span>
<span class="attribution"><span class="source">Christine Hatch</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<p><a href="https://www.fs.fed.us/t-d/pubs/pdfpubs/pdf05772830/pdf05772830dpi300.pdf">Culvert guards</a>, fences and other exclusion devices can keep beavers a safe distance from infrastructure and maintain pond heights at a level that won’t flood adjoining areas. Road crossings over streams that are designed to <a href="https://streamcontinuity.org">let fish and other aquatic animals through instead of blocking them</a> are beaver-friendly and will be resilient to climate change and extreme precipitation events. If these structures are large enough to let debris pass through, then beavers will build dams upstream instead, which can help catch floodwaters.</p>
<p>[<em>Over 140,000 readers rely on The Conversation’s newsletters to understand the world.</em> <a href="https://memberservices.theconversation.com/newsletters/?source=inline-140ksignup">Sign up today</a>.]</p>
<p>A growing body of research shows that setting aside pockets of land for beavers is good for wetland ecosystems, biodiversity and rivers. I believe we can learn from beavers’ water management skills, coexist with them in our landscapes and incorporate their natural engineering in response to weather and precipitation patterns disrupted by climate change.</p><img src="https://counter.theconversation.com/content/168545/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Christine Hatch has trained workers at the Massachusetts Department of Transportation on Rivers and Roads, mainly free of charge as public outreach work.
</span></em></p>Beavers in our landscapes have great potential to provide small-scale adaptations to climate change – if humans can figure out how to live with them.Christine E. Hatch, Professor of Geosciences, UMass AmherstLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1731622021-12-05T07:18:57Z2021-12-05T07:18:57ZSoil isn’t dirt: it’s the foundation of life and needs real care<figure><img src="https://images.theconversation.com/files/435542/original/file-20211203-27-1fw2c5m.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">shutterstock</span> </figcaption></figure><p>Healthy soil is critical for life on earth. It can contribute to climate change mitigation and adaptation, food and nutrition security. It is central to achieving sustainable development goals. It is the foundation of life on land. It provides many ecosystem services and helps achieve ecosystem restoration. </p>
<p>The biggest challenge when it comes to soil is getting people to stop treating soil like dirt and start treating it with the respect it deserves. And this comes from soil stewardship, really caring for the land. But to do that, it’s important to understand the soil ecosystem that needs restoring. </p>
<p><a href="https://theconversation.com/lessons-from-kenya-on-how-to-restore-degraded-land-98178">Land degradation</a> is a serious problem when it comes to soil. Degraded landscapes are more vulnerable to the stresses of droughts, floods and erratic rainfall. Education about good soil practices is key, and people like farmers who use the soil need the tools to practise good soil management. </p>
<p>In today’s episode of Pasha, Leigh Ann Winowiecki, a soil systems scientist at the World Agroforestry, and Rattan Lal, a distinguished professor of soil science at Ohio State University, discuss why soil needs to be front and centre of global policies.</p>
<p>We’ve also collected some more articles about soil <a href="https://theconversation.com/africa/search?q=%23WorldSoilDay2021&sort=recency&language=en&date=all&date_from=&date_to=">here</a>.</p>
<hr>
<p><strong>Photo:</strong>
“Arid landscape in north Senegal. Eroded soil with few acacia trees. Traces of erosion on the sandy ground. Dry climate conducting to the desertification. Natural picture taken during the dry season.” By Boulenger Xavier <a href="https://www.shutterstock.com/image-photo/arid-landscape-north-senegal-eroded-soil-1020803248">Shutterstock</a></p>
<p><strong>Music</strong>
“Happy African Village” by John Bartmann, found on <a href="http://freemusicarchive.org/music/John_Bartmann/Public_Domain_Soundtrack_Music_Album_One/happy-african-village">FreeMusicArchive.org</a> licensed under <a href="https://creativecommons.org/publicdomain/zero/1.0/">CC0 1</a>.</p>
<p>“minimal ambient music/atmosphere fragment” by Clacksberg found on <a href="https://freesound.org/people/Clacksberg/sounds/495747/">Freesound</a> licensed under <a href="http://creativecommons.org/publicdomain/zero/1.0/">Creative Commons</a></p><img src="https://counter.theconversation.com/content/173162/count.gif" alt="The Conversation" width="1" height="1" />
The global community must understand the importance of soil in order to protect it.Ozayr Patel, Digital EditorLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1716572021-11-16T20:34:44Z2021-11-16T20:34:44ZVery hungry caterpillars can have large effects on lake quality and carbon emissions<figure><img src="https://images.theconversation.com/files/432041/original/file-20211115-17-zxtklw.JPG?ixlib=rb-1.1.0&rect=47%2C35%2C3898%2C2173&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">These insects are basically little machines that convert carbon-rich leaves into nitrogen-rich poo.</span> <span class="attribution"><span class="source">(John Gunn)</span>, <span class="license">Author provided</span></span></figcaption></figure><p>Outbreaks of invasive moth caterpillars, <em>Lymantria dispar dispar</em>, and forest tent caterpillar moths, <em>Malacasoma disstria</em>, occur at least every five years in temperate forests. The insects munch through so many leaves that <a href="https://doi.org/10.1038/s41467-021-26666-1">our research has found</a> the resulting decrease in leaf-fall and increase in caterpillar poop hugely alter the way nutrients, particularly carbon and nitrogen, cycle between land and nearby lakes.</p>
<p>Nitrogen-rich insect excrement, called frass, can wash into lake water and act as fertilizer for microbes. These microbes can then release carbon dioxide into the atmosphere as they metabolize the frass. In years with insect outbreaks, the large quantities of frass may favour the growth of bacteria that release greenhouse gases in lakes <a href="https://doi.org/10.4319/lo.1984.29.2.0298">overpowering the lake algae that remove carbon dioxide from the atmosphere</a>.</p>
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Read more:
<a href="https://theconversation.com/why-an-invasive-caterpillar-is-munching-its-way-through-tree-leaves-in-the-largest-outbreak-in-decades-163346">Why an invasive caterpillar is munching its way through tree leaves, in the largest outbreak in decades</a>
</strong>
</em>
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<figure class="align-right ">
<img alt="Caterpillars on a chewed green leaf." src="https://images.theconversation.com/files/432074/original/file-20211115-13-1j2he1b.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/432074/original/file-20211115-13-1j2he1b.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=412&fit=crop&dpr=1 600w, https://images.theconversation.com/files/432074/original/file-20211115-13-1j2he1b.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=412&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/432074/original/file-20211115-13-1j2he1b.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=412&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/432074/original/file-20211115-13-1j2he1b.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=518&fit=crop&dpr=1 754w, https://images.theconversation.com/files/432074/original/file-20211115-13-1j2he1b.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=518&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/432074/original/file-20211115-13-1j2he1b.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">
<figcaption>
<span class="caption">Tree leaves eaten by caterpillars on Montreal’s Mount Royal in July 2021.</span>
<span class="attribution"><span class="source">THE CANADIAN PRESS/Paul Chiasson</span></span>
</figcaption>
</figure>
<p>These insects are basically little machines that convert carbon-rich leaves into nitrogen-rich poo. The poo drops into lakes instead of the leaves, and this significantly changes the water chemistry. We think it will further increase the extent to which lakes are sources of greenhouse gases. </p>
<p>As the climate in the world’s temperate region shifts, insect populations are expected to increase and move northwards. This puts <a href="https://doi.org/10.1046/j.1365-2486.2002.00451.x">northern forests at increased risk of defoliator outbreaks in the future</a>, potentially causing greater quantities of carbon dioxide to be released from nearby lakes. Climate change is also expected to favour the growth of broad-leaved deciduous trees around the lakes, which we have found will amplify the insects’s impact.</p>
<h2>Where is the good news?</h2>
<p>While the impacts of insect defoliation appear to be on the rise in both frequency and severity, lake waters across the Canadian Shield are also undergoing a <a href="https://doi.org/10.1038/444283a">process called browning</a> due to a build up of tea-like dissolved organic carbon in lake water. </p>
<p>This declining clarity of lakes has been attributed to many factors including climate change and their recovery from historical acid rain and logging activities. Our 32-year-long monitoring study showed that an outbreak of leaf-munching caterpillars can effectively offset an entire year’s worth of carbon accumulation in nearby lakes, significantly improving water clarity.</p>
<figure class="align-center ">
<img alt="A view of autumn trees along a lake shoreline" src="https://images.theconversation.com/files/432078/original/file-20211115-13-hlgdt0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/432078/original/file-20211115-13-hlgdt0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/432078/original/file-20211115-13-hlgdt0.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/432078/original/file-20211115-13-hlgdt0.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/432078/original/file-20211115-13-hlgdt0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/432078/original/file-20211115-13-hlgdt0.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/432078/original/file-20211115-13-hlgdt0.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">An outbreak of leaf-munching caterpillars can effectively offset an entire year’s worth of carbon accumulation in nearby lakes, significantly improving water clarity.</span>
<span class="attribution"><span class="source">(Unsplash)</span></span>
</figcaption>
</figure>
<p>In years without outbreaks of leaf-eating insects, carbon and nitrogen entering lakes usually comes from decaying leaves and conifer needles. These inputs typically peak in quantity in autumn. In outbreak years, we found that nearby freshwater lakes, especially those surrounded by deciduous forests had one-third less dissolved carbon or “forest tea” in the water, because the hungry caterpillars effectively held back the flow of carbon to the lake.</p>
<p>The lasting benefits of these marauding insects becomes evident when the invasive insects encounter already stressed trees, such as the stunted birch forest surrounding the massive metal smelters in Sudbury, Ont. This 80,000 hectare industrial area is undergoing a remarkable natural recovery of its own, because of a <a href="https://theconversation.com/what-mining-oil-and-gas-industries-can-learn-from-sudbury-the-city-that-went-from-major-polluter-to-thriving-environment-165595">98 per cent reduction in acid and metal particulate emissions</a> from what was <a href="https://www.goodnewsnetwork.org/sudbury-now-has-cleanest-air-in-region/">the world’s largest point sources of sulphur pollution as recently as the 1970s</a>. The legacy of soil loss, contamination and degradation in Sudbury clearly puts trees at a disadvantage in the battle with defoliating insects.</p>
<h2>Caterpillars as tiny plows?</h2>
<p>Trees can’t flee from insects but usually can survive multiple heavy attacks. However, trees in the industrial barrens of Sudbury don’t fare so well, because of all the other stresses they face. </p>
<p>These stressors include the loss of soil moisture and organic matter, and decades of accumulated toxic metal particles from the smelters. The result is that these stressed trees present themselves as a delicious food source for caterpillars and other insects and the landscape is often littered with dead and dying trees on their way to becoming soil.</p>
<p><a href="https://doi.org/10.1093/ee/nvz096">In earlier lab experiments</a>, we showed that when we fed <em>L. dispar</em> caterpillars leaves from the stressed white birch trees of the industrial barrens they ate more leaves and produced far more frass, which increased plant growth in soil that had received this rain of poo. </p>
<p>Yes, the insects are giving the struggling trees a very hard time at the industrial sites. But the improving soil quality is the real winner. </p>
<p>Healthy <a href="https://e360.yale.edu/features/soil_as_carbon_storehouse_new_weapon_in_climate_fight">soil is one of the largest and safest places to sequester carbon from the atmosphere</a>, key in our fight against climate change. As every farmer knows, protecting and restoring soil quality is also essential for sustainable agriculture. That is why well-informed farmers regularly try to stop extracting nutrients from the soil and plow in a nutrient-rich fodder crop like alfalfa to rebuild the soil.</p>
<p>Our research shows that these hungry caterpillars now appear to play surprisingly large roles in altering key features of the global carbon cycle, but we also now think of them as tiny plows that can help improve degraded soils.</p><img src="https://counter.theconversation.com/content/171657/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>John Gunn receives funding from organisation.
NSERC, CRC, CFI, Mitacs, OCE, Vale, Glencore, Wildlife Conservation Society, DFO, Friends of Killarney</span></em></p><p class="fine-print"><em><span>Andrew J Tanentzap receives funding from the Natural Environment Research Council, Biotechnology and Biological Sciences Research Council, and European Research Council.</span></em></p><p class="fine-print"><em><span>Samuel Woodman receives funding from NSERC and the Cambridge Trust. </span></em></p>As environmental engineers, invasive caterpillars can have remarkable effects on water quality and soil conditions. But from a climate perspective they’re pretty much a nuisance.John Gunn, Canada Research Chair in Stressed Aquatic Systems, Laurentian UniversityAndrew J Tanentzap, Reader in Global Change Ecology, University of CambridgeSamuel Woodman, PhD Student, Ecosystem and Global Change, University of CambridgeLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1703362021-11-05T10:18:03Z2021-11-05T10:18:03ZForests can’t handle all the net-zero emissions plans – companies and countries expect nature to offset too much carbon<figure><img src="https://images.theconversation.com/files/430350/original/file-20211104-20835-1f2bx5q.jpg?ixlib=rb-1.1.0&rect=404%2C11%2C3447%2C2233&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Companies' net-zero pledges count on vast expanses of forest to hold carbon so they can continue emitting.</span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/news-photo/this-photo-taken-on-may-13-2018-shows-an-aerial-view-of-the-news-photo/958257276">AFP via Getty Images</a></span></figcaption></figure><p>Net-zero emissions pledges to protect the climate are coming fast and furious from <a href="https://www.theclimatepledge.com/">companies</a>, <a href="https://www.un.org/en/climatechange/net-zero-coalition">cities and countries</a>. But declaring a net-zero target doesn’t mean they plan to stop their greenhouse gas emissions entirely – far from it. Most of these pledges rely heavily on planting trees or protecting forests or farmland to absorb some of their emissions.</p>
<p>That raises two questions: Can nature handle the expectations? And, more importantly, should it even be expected to?</p>
<p>We have been involved in international climate negotiations and <a href="https://scholar.google.ca/citations?user=ZqBsd8YAAAAJ&hl=en">land and forest</a> <a href="https://www.researchgate.net/profile/Doreen-Stabinsky">climate research</a> for years. Research and pledges from companies so far suggest that the answer to these questions is no. </p>
<h2>What is net-zero?</h2>
<p>Net-zero is the point at which all the carbon dioxide still emitted by human activities, such as running fossil fuel power plants or driving gas-powered vehicles, is balanced by the removal of carbon dioxide from the atmosphere. Since the world <a href="https://doi.org/10.1021/acs.est.1c03263">does not yet have technologies</a> capable of removing carbon dioxide from air at any climate-relevant scale, that means relying on nature for carbon dioxide removal.</p>
<p>According to the Intergovernmental Panel on Climate Change, global carbon dioxide emissions will need to reach <a href="https://www.ipcc.ch/report/ar6/wg1/downloads/report/IPCC_AR6_WGI_Annex_VII.pdf">net-zero by at least midcentury</a> for the world to have even a small chance of limiting warming to 1.5 degrees Celsius (2.7 F), an aim of the <a href="https://unfccc.int/process-and-meetings/the-paris-agreement/the-paris-agreement">Paris climate agreement</a> to avoid the worst impacts of climate change.</p>
<p>The devil of net-zero, of course, lies in its apparent simplicity.</p>
<h2>Nature’s potential and its limits</h2>
<p>Climate change is driven largely by cumulative emissions – carbon dioxide that accumulates in the atmosphere and stays there for <a href="https://tos.org/oceanography/article/an-accounting-of-the-observed-increase-in-oceanic-and-atmospheric-co2-and-a">hundreds to thousands of years</a>, trapping heat near Earth’s surface.</p>
<p>Nature has received a great deal of attention for its ability to remove carbon dioxide from the atmosphere and store it in the biosphere, such as in soils, grasslands, trees and mangroves, <a href="https://ssec.si.edu/stemvisions-blog/what-photosynthesis">via photosynthesis</a>. It is also a source of carbon dioxide emissions through deforestation, land and ecosystem degradation and agricultural practices. However, the right kinds of changes to land management practices can reduce emissions and improve carbon storage.</p>
<p>Net-zero proposals count on finding ways for these systems to take up more carbon than they already absorb.</p>
<p><iframe id="psjFZ" class="tc-infographic-datawrapper" src="https://datawrapper.dwcdn.net/psjFZ/1/" height="400px" width="100%" style="border: none" frameborder="0"></iframe></p>
<p>Researchers estimate that <a href="https://doi.org/10.1038/d41586-021-01241-2">nature might annually be able to remove</a> 5 gigatons of carbon dioxide from the air and avoid another 5 gigatons through stopping emissions from deforestation, agriculture and other sources. </p>
<p>This 10-gigaton figure <a href="https://www.twn.my/title2/briefing_papers/twn/NbS%20mitigation%20TWNBP%20Oct%202021%20Stabinsky.pdf">has regularly been cited</a> as “one-third of the global effort needed to stop climate change,” but that’s misleading. Avoided emissions and removals are not additive. </p>
<p>A new <a href="https://ukcop26.org/glasgow-leaders-declaration-on-forests-and-land-use/">forests and land-use declaration</a> announced at the UN climate conference in November also highlights the <a href="https://theconversation.com/cop26-global-deforestation-deal-will-fail-if-countries-like-australia-dont-lift-their-game-on-land-clearing-171108">ongoing challenges</a> in bringing deforestation emissions to zero, including illegal logging and protecting the rights of Indigenous peoples.</p>
<h2>Stored carbon doesn’t stay there forever</h2>
<p>Reaching the point at which nature can remove 5 gigatons of carbon dioxide each year would take time. And there’s another problem: High levels of removal might last for only a decade or so.</p>
<p>When growing trees and restoring ecosystems, the storage potential develops to a peak over decades. While this continues, it reduces over time as ecosystems become saturated, meaning large-scale carbon dioxide removal by natural ecosystems is a <a href="https://www.nature.com/articles/nclimate1804?proof=t">one-off opportunity to restore lost carbon stocks</a>. </p>
<p>Carbon stored in the terrestrial biosphere – in forests and other ecosystems – doesn’t stay there forever, either. Trees and plants die, sometimes as a result of <a href="https://www.nytimes.com/2021/08/23/us/wildfires-carbon-offsets.html">climate-related wildfires</a>, droughts and warming, and fields are tilled and release carbon.</p>
<p>When taking these factors into consideration – the delay while nature-based removals scale up, saturation and the <a href="https://doi.org/10.1038/NCLIMATE1804">one-off and reversible nature</a> of enhanced terrestrial carbon storage – another team of researchers found that restoration of forest and agricultural ecosystems could be expected to remove only about <a href="https://ore.exeter.ac.uk/repository/handle/10871/127015">3.7 gigatons of carbon dioxide annually</a>.</p>
<p>Over the century, ecosystem restoration might reduce global average temperature by <a href="https://ore.exeter.ac.uk/repository/handle/10871/127015">approximately 0.12 C (0.2 F)</a>. But the scale of removals the world can expect from ecosystem restoration will not happen in time to reduce the warming that is expected within the next two decades.</p>
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<h2>Nature in net-zero pledges</h2>
<p>Unfortunately there is not a great deal of useful information contained in net-zero pledges about the relative contributions of planned emissions reductions versus dependence on removals. There are, however, some indications of the magnitude of removals that major actors expect to have available for their use.</p>
<p><a href="https://actionaid.org/sites/default/files/publications/Not-Their-Lands_Media%20Briefing.pdf">ActionAid reviewed</a> the oil major <a href="https://www.shell.com/investors/annual-general-meeting/_jcr_content/par/textimage_d70a_copy.stream/1618407326759/7c3d5b317351891d2383b3e9f1e511997e516639/shell-energy-transition-strategy-2021.pdf">Shell’s net-zero</a> strategy and found that it includes offsetting 120 million tons of carbon dioxide per year through planting forests, estimated to require around 29.5 million acres (12 million hectares) of land. That’s roughly 45,000 square miles.</p>
<p><a href="https://oxfamilibrary.openrepository.com/bitstream/handle/10546/621205/bp-net-zero-land-food-equity-030821-en.pdf">Oxfam reviewed</a> the net-zero pledges for Shell and three other oil and gas producers – BP, TotalEnergies and ENI – and concluded that “their plans alone could require an area of land twice the size of the U.K. If the oil and gas sector as a whole adopted similar net zero targets, it could end up requiring land that is nearly half the size of the United States, or one-third of the world’s farmland.”</p>
<p>These numbers provide insight into how these companies, and perhaps many others, view net-zero.</p>
<p>Research indicates that net-zero strategies that rely on temporary removals to balance permanent emissions will fail. The temporary storage of nature-based removals, limited land availability and the time they take to scale up mean that, while they are a critical part of <a href="https://doi.org/10.1073/pnas.1810141115">stabilizing the earth system</a>, they cannot compensate for continued fossil fuel emissions.</p>
<p>This means that getting to net-zero will require rapid and dramatic reductions in emissions. Nature will be called upon to balance out what is left, mostly emissions from agriculture and land, but nature cannot balance out ongoing fossil emissions.</p>
<p>To actually reach net-zero will require reducing emissions close to zero.</p>
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<img alt="COP26: the world’s biggest climate talks" src="https://images.theconversation.com/files/424739/original/file-20211005-17-cgrf2z.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/424739/original/file-20211005-17-cgrf2z.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=600&fit=crop&dpr=1 600w, https://images.theconversation.com/files/424739/original/file-20211005-17-cgrf2z.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=600&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/424739/original/file-20211005-17-cgrf2z.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=600&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/424739/original/file-20211005-17-cgrf2z.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=754&fit=crop&dpr=1 754w, https://images.theconversation.com/files/424739/original/file-20211005-17-cgrf2z.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=754&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/424739/original/file-20211005-17-cgrf2z.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 story is part of The Conversation’s coverage of COP26, the Glasgow climate conference, by experts from around the world.</strong>
<br><em>Amid a rising tide of climate news and stories, The Conversation is here to clear the air and make sure you get information you can trust. <a href="https://theconversation.com/us/cop26">Read more of our U.S.</a> and <a href="https://page.theconversation.com/cop26-glasgow-2021-climate-change-summit/">global coverage</a>.</em></p><img src="https://counter.theconversation.com/content/170336/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Doreen Stabinsky is affiliated with the Climate, Land, Ambition, and Rights Alliance (CLARA).</span></em></p><p class="fine-print"><em><span>Kate Dooley receives funding from One Earth Philanthropy.</span></em></p>Yes, trees and soils can absorb and store carbon, but the carbon doesn’t stay stored forever. That’s one of the problems with how net-zero plans for the climate are being designed.Doreen Stabinsky, Professor of Global Environmental Politics, College of the AtlanticKate Dooley, Research Fellow, Climate & Energy College, The University of MelbourneLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1684742021-09-26T11:00:59Z2021-09-26T11:00:59ZThe clock is ticking on net-zero, farmers must not get a free pass<figure><img src="https://images.theconversation.com/files/423067/original/file-20210924-17-145afmf.jpg?ixlib=rb-1.1.0&rect=24%2C16%2C5469%2C3549&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">Dan Peled/AAP</span></span></figcaption></figure><p>Political momentum is growing in Australia to cut greenhouse gas emissions to net-zero by 2050. On Friday, Treasurer Josh Frydenberg was the latest member of the federal government to <a href="https://www.theguardian.com/australia-news/2021/sep/24/josh-frydenberg-to-make-case-for-net-zero-saying-australia-cant-risk-being-seen-as-a-climate-change-pariah">throw his weight</a> behind the goal, and over the weekend, Prime Minister Scott Morrison <a href="https://www.theguardian.com/australia-news/2021/sep/25/scott-morrison-says-australia-really-good-at-digging-stuff-up-while-announcing-clean-energy-summit">acknowledged</a> “the world is transitioning to a new energy economy”.</p>
<p>But for Australia to achieve net-zero across the economy, emissions from agriculture must fall dramatically. Agriculture contributed about 15% to Australia’s greenhouse gas emissions in 2019 – most of it from cattle and sheep. If herd numbers recover from the recent drought, the sector’s emissions are projected to rise.</p>
<p>Cutting agriculture emissions will not be easy. The difficulties have <a href="https://theconversation.com/agitated-nationals-grapple-with-climate-debate-as-former-minister-chester-takes-a-break-from-party-room-168736">reportedly</a> triggered concern in the Nationals’ about the cost of the transition for farmers, including calls for agriculture to be <a href="https://theconversation.com/nationals-push-to-carve-farming-from-a-net-zero-target-is-misguided-and-dangerous-154822">carved out</a> of any net-zero target.</p>
<p>But as our new Grattan Institute <a href="https://grattan.edu.au/report/towards-net-zero-practical-policies-to-reduce-agricultural-emissions/">report</a> today makes clear, agriculture must not be granted this exemption. Instead, the federal government should do more to encourage farmers to adopt low-emissions technologies and practices – some of which can be deployed now.</p>
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Read more:
<a href="https://theconversation.com/nationals-push-to-carve-farming-from-a-net-zero-target-is-misguided-and-dangerous-154822">Nationals' push to carve farming from a net-zero target is misguided and dangerous</a>
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<img alt="four people walk through dusty farm" src="https://images.theconversation.com/files/423068/original/file-20210924-22-1wf97es.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/423068/original/file-20210924-22-1wf97es.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/423068/original/file-20210924-22-1wf97es.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/423068/original/file-20210924-22-1wf97es.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/423068/original/file-20210924-22-1wf97es.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/423068/original/file-20210924-22-1wf97es.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/423068/original/file-20210924-22-1wf97es.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">
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<span class="caption">The Morrison government must do more to help farmers get on the path to net-zero.</span>
<span class="attribution"><span class="source">Alex Ellinghausen AAP/Fairfax Media pool</span></span>
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<h2>Three good reasons farmers must go net-zero</h2>
<p>Many farmers want to be part of the climate solution – and must be – for three main reasons. </p>
<p>First, the agriculture sector is uniquely vulnerable to a changing climate. Already, changes in rainfall have <a href="https://www.agriculture.gov.au/abares/products/insights/climate-change-impacts-and-adaptation#recent-changes-in-seasonal-conditions-have-affected-the-profitability-of-australian-farms">cut profits</a> across the sector by 23% compared to what could have been achieved in pre-2000 conditions. The effect is even worse for cropping farmers.</p>
<p>Livestock farmers face risks, too. If global warming reaches 3°C, livestock in northern Australia are expected to suffer heat stress <a href="https://www.science.org.au/supporting-science/science-policy-and-analysis/reports-and-publications/risks-australia-three-degrees-c-warmer-world">almost daily</a>. </p>
<p>Second, parts of the sector are highly exposed to international markets – for example, about <a href="https://www.agriculture.gov.au/abares/products/insights/snapshot-of-australian-agriculture-2021#around-70-of-agricultural-output-is-exported">three-quarters</a> of Australia’s red meat is exported. </p>
<p>There are fears Australian producers may <a href="https://www.farmonline.com.au/story/7112772/trade-partners-may-tax-aussie-ag-exports-if-no-carbon-neutral-target-is-set/">face a border tax</a> in some markets if they don’t cut emissions.
The European Union, for instance, plans to introduce tariffs <a href="https://cdn.aigroup.com.au/Reports/2021/Carbon_Border_Adjustments_Policy_Paper.pdf">as early as 2023</a> on some products from countries without effective carbon pricing, though agriculture will not be included initially.</p>
<p>Third, the industry recognises action on climate change can often <a href="https://farmersforclimateaction.org.au/wp-content/uploads/2021/09/FCA-EY-FINAL-Report-Low-emissions-future-for-Agriculture.pdf">boost farm productivity</a>, or help farmers secure <a href="https://www.agriculture.gov.au/ag-farm-food/natural-resources/landcare/sustaining-future-australian-farming/carbon-biodiversity-pilot">resilient revenue streams</a>. For example, trees provide shade for animals, while good soil management can preserve the land’s fertility. Both activities can store carbon and may generate carbon credits.</p>
<p>Carbon credits can be used to offset farm emissions, or sold to other emitters. In a net-zero future, farmers can maximise their carbon credit revenue by minimising their own emissions, leaving them more carbon credits to sell. </p>
<p>The agriculture sector itself is increasingly embracing the net-zero goal. The National Farmers Federation <a href="https://nff.org.au/key-issue/climate-change/">supports</a> an economy-wide aspiration to be net-zero by 2050, with some conditions. The <a href="http://rmac.com.au/red-meat-2030/">red meat</a> and <a href="https://australianpork.com.au/sites/default/files/2021-05/APL-Strategic-Plan-2020-2025.pdf#page=8">pork</a> industries have gone further, committing to be carbon neutral by 2030 and 2025 respectively. </p>
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<strong>
Read more:
<a href="https://theconversation.com/land-of-opportunity-more-sustainable-australian-farming-would-protect-our-lucrative-exports-and-the-planet-166177">Land of opportunity: more sustainable Australian farming would protect our lucrative exports (and the planet)</a>
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<img alt="hand presses soil" src="https://images.theconversation.com/files/423070/original/file-20210924-25-lncfwv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/423070/original/file-20210924-25-lncfwv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/423070/original/file-20210924-25-lncfwv.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/423070/original/file-20210924-25-lncfwv.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/423070/original/file-20210924-25-lncfwv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/423070/original/file-20210924-25-lncfwv.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/423070/original/file-20210924-25-lncfwv.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">
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<span class="caption">Good soil management aids a farm’s fertility.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
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<h2>What can be done?</h2>
<p>Australian agricultural activities emitted about 76 million tonnes of carbon dioxide-equivalent emissions in 2019. Of this, about <a href="https://ageis.climatechange.gov.au/UNFCCC.aspx">48 million tonnes were methane belched by cattle and sheep</a>, and a further 11 million came from their excrement.</p>
<p>The sector’s non-animal emissions largely came from burning diesel, the use of fertiliser, and the breakdown of leftover plant material from cropping.</p>
<p>Unlike in, say, the electricity sector, it’s <a href="https://www.pce.parliament.nz/media/196523/report-farms-forests-and-fossil-fuels.pdf">not possible</a> to completely eliminate agricultural emissions, and deep emissions cuts look difficult in the near term. That’s because methane produced in the stomachs of cattle and sheep represents more than 60% of agricultural emissions; these cannot be captured, or eliminated through renewable energy technology.</p>
<p>Supplements added to stock feed - which reduce the amount of methane the animal produces - are the most promising options to reduce agricultural emissions. These supplements include <a href="https://www.mdpi.com/2076-2615/11/4/951/htm">red algae</a> and the chemical <a href="https://www.mla.com.au/news-and-events/industry-news/the-feed-additive-reducing-methane-emissions-by-up-to-90/">3-nitrooxypropanol</a>, both of which may cut methane by up to 90% if used consistently at the right dose. </p>
<p>But it’s difficult to distribute these feed supplements to Australian grazing cattle and sheep every day. At any given time, <a href="https://www.feedlots.com.au/faq">only about 4%</a> of Australia’s cattle are in feedlots where their diet can be easily controlled. </p>
<p>Diesel use can be reduced by electrifying farm machinery, but electric models are <a href="https://www.sciencedirect.com/science/article/pii/S095965262100250X">not yet widely available</a> or affordable for all purposes. </p>
<p>These challenges slow the realistic rate at which the sector can cut emissions. Yet there are things that can be done today. </p>
<p>Many manure emissions can be avoided through smarter management. For example, on intensive livestock farms, manure is often stored in ponds where it releases methane. This methane can be <a href="http://www.cleanenergyregulator.gov.au/ERF/Pages/Choosing%20a%20project%20type/Opportunities%20for%20the%20land%20sector/Agricultural%20methods/Animal-effluent-management-method.aspx">captured and burnt</a>, emitting the weaker greenhouse gas, carbon dioxide, instead. </p>
<p>And better targeted fertiliser use is <a href="https://www.agric.wa.gov.au/climate-change/reducing-nitrous-oxide-emissions-agricultural-soils-western-australia">a clear win-win</a> – it would save farmers money and reduce emissions of nitrous oxide, a potent greenhouse gas.</p>
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<img alt="sheep in lots" src="https://images.theconversation.com/files/423071/original/file-20210924-21-1wevd8d.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/423071/original/file-20210924-21-1wevd8d.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/423071/original/file-20210924-21-1wevd8d.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/423071/original/file-20210924-21-1wevd8d.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/423071/original/file-20210924-21-1wevd8d.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=502&fit=crop&dpr=1 754w, https://images.theconversation.com/files/423071/original/file-20210924-21-1wevd8d.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=502&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/423071/original/file-20210924-21-1wevd8d.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=502&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<span class="caption">Supplements added to stock feed are a promising way to cut emissions.</span>
<span class="attribution"><span class="source">Dean Lewins/AAP</span></span>
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<h2>Governments must walk and chew gum</h2>
<p>An economy-wide carbon price would be the best way for Australia to reduce emissions in an economically efficient manner. But the political reality is that carbon pricing is out of reach, at least for now. So Australia should pursue sector-specific policies – including in agriculture.</p>
<p>Governments must walk and chew gum. That means introducing policies to support emissions-reducing actions that farmers can take today, while investing alongside the industry in potential high-impact solutions for the longer term.</p>
<p>Accelerating near-term action will require improving the federal government’s <a href="https://www.climatechangeauthority.gov.au/sites/default/files/2020-11/ERF%20Review%20Final%20Report%2020201009_2.pdf">Emissions Reduction Fund</a>, to help more farmers generate Australian carbon credit units. It will also require more investment in outreach programs to give farmers the knowledge they need to reduce emissions.</p>
<p>Improving the long-term emissions outlook for the agriculture sector requires investment in high-impact research, development and deployment. Bringing down the cost of new technologies is possible with deployment at scale: all governments should consider what combination of subsidies, penalties and regulations will best <a href="https://www.afr.com/policy/energy-and-climate/net-zero-target-requires-three-legged-stool-of-action-20210423-p57luv">drive this</a>.</p>
<p>Agriculture must not become the missing piece in Australia’s net-zero puzzle. Without action today, the sector may become Australia’s largest source of emissions in coming decades. This would require hugely expensive carbon offsetting - paid for by taxpayers, consumers and farmers themselves.
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Read more:
<a href="https://theconversation.com/agitated-nationals-grapple-with-climate-debate-as-former-minister-chester-takes-a-break-from-party-room-168736">Agitated Nationals grapple with climate debate, as former minister Chester takes 'a break' from party room</a>
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<p class="fine-print"><em><span>Grattan Institute began with contributions to its endowment of $15 million from each of the Federal and Victorian Governments, $4 million from BHP Billiton, and $1 million from NAB. In order to safeguard its independence, Grattan Institute’s board controls this endowment. The funds are invested and contribute to funding Grattan Institute's activities. Grattan Institute also receives funding from corporates, foundations, and individuals to support its general activities as disclosed on its website.</span></em></p>Some Nationals want agriculture carved out of any net-zero target. Cutting emissions from farms won’t be easy, but it’s essential.James Ha, Associate, Grattan InstituteLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1676232021-09-13T15:06:30Z2021-09-13T15:06:30ZFood production generates more than a third of manmade greenhouse gas emissions – a new framework tells us how much comes from crops, countries and regions<figure><img src="https://images.theconversation.com/files/420618/original/file-20210912-21-3kt2ys.jpg?ixlib=rb-1.1.0&rect=26%2C6%2C4452%2C2974&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">A farmer walks through a rice paddy in India's northeastern state of Assam. </span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/news-photo/farmer-walks-through-a-paddy-fields-at-mayong-in-morigaon-news-photo/1205044470">Buu Boro /AFP via Getty Images</a></span></figcaption></figure><p>Producing enough food for a growing world population is <a href="https://theconversation.com/world-hunger-surged-in-2020-with-1-in-10-people-on-earth-undernourished-164379">an urgent global challenge</a>. And it’s complicated by the fact that climate change is warming the Earth and <a href="https://theconversation.com/world-hunger-has-risen-for-three-straight-years-and-climate-change-is-a-cause-103818">making farming harder in many places</a>.</p>
<p>Food production is a big contributor to climate change, so it’s critically important to be able to measure greenhouse gas emissions from the food sector accurately. In a <a href="http://dx.doi.org/10.1038/s43016-021-00358-x">new study</a>, we show that the food system generates about 35% of total global man-made greenhouse gas emissions. </p>
<p>Breaking down this share, production of animal-based foods – meat, poultry and dairy products, including growing crops to feed livestock and pastures for grazing – contributes 57% of emissions linked to the food system. Raising plant-based foods for human consumption contributes 29%. The other 14% of agricultural emissions come from products not used as food or feed, such as cotton and rubber. </p>
<p>We are atmospheric scientists who study the effects of <a href="https://scholar.google.com/citations?user=eYUGehcAAAAJ&hl=en">agriculture</a> and <a href="https://scholar.google.com/citations?user=AiFaZvYAAAAJ&hl=en">other human activities</a> on Earth’s climate. It’s well known that producing animal-based foods generates more greenhouse gas emissions than plant-based foods, which is why <a href="https://www.ipcc.ch/srccl/chapter/chapter-5/">shifting toward a more plant-based diet</a> is recognized as an option for curbing greenhouse gas emissions and climate change. </p>
<p>But to quantify the potential impact of such a shift, we saw a need for better tools to estimate emissions from individual plant- and animal-based food items, with more details about how emissions are calculated and covering all food-related sub-sectors, such as land use change and actions beyond the farm gate. </p>
<p>Current methods rely on sparse data and simplified representations of many key factors, such as emissions from farmland management. They don’t treat different sub-sectors consistently or calculate emissions for producing many specific commodities.</p>
<p>To fill those gaps, we have developed a comprehensive framework that combines modeling and various databases. It enables us to estimate average yearly global emissions of the greenhouse gases carbon dioxide, methane and nitrous oxide from the production and consumption of plant- and animal-based human food. Currently, our study covers the years 2007-2013. Here are some of the insights it offers, using data that represents an average of those years.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/bjN4t9fWza0?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Hunger and food insecurity are urgent global challenges. Climate change is one contributing factor.</span></figcaption>
</figure>
<h2>Greenhouse gases from food production</h2>
<p>We considered four major sub-sectors of emissions from plant- and animal-based food production. Overall, we calculated that the food system produces emissions that are equivalent to approximately 17.3 billion metric tons (17.318 teragrams) of carbon dioxide yearly. </p>
<p>Land use change – clearing forests for farms and ranches, which reduces carbon storage in trees and soils – accounts for 29% of total food production greenhouse gas emissions. Another 38% comes from farmland management activities, such as plowing fields, which reduces soil carbon storage, and treating crops with nitrogen fertilizer. Farmers also burn a lot of fossil fuel to run their tractors and harvesters. </p>
<p>Raising livestock generates 21% of greenhouse gas emissions from food production. It includes <a href="https://climate.nasa.gov/faq/33/which-is-a-bigger-methane-source-cow-belching-or-cow-flatulence/">methane belched by grazing animals</a>, as well as methane and nitrous oxide released from livestock manure. The remaining 11% comes from activities that occur beyond farm gates, such as mining, manufacturing and transporting fertilizers and pesticides, as well as energy use in food processing.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/420621/original/file-20210912-21-rruhyv.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Graphic of agricultural greenhouse gas sources and sinks." src="https://images.theconversation.com/files/420621/original/file-20210912-21-rruhyv.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/420621/original/file-20210912-21-rruhyv.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=211&fit=crop&dpr=1 600w, https://images.theconversation.com/files/420621/original/file-20210912-21-rruhyv.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=211&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/420621/original/file-20210912-21-rruhyv.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=211&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/420621/original/file-20210912-21-rruhyv.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=265&fit=crop&dpr=1 754w, https://images.theconversation.com/files/420621/original/file-20210912-21-rruhyv.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=265&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/420621/original/file-20210912-21-rruhyv.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=265&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Many agricultural activities release carbon dioxide (CO₂), methane (CH₄) and nitrous oxide (N₂O) to the atmosphere. Some store carbon in plants and soil.</span>
<span class="attribution"><a class="source" href="https://www.everycrsreport.com/reports/IF11404.html">CRS</a></span>
</figcaption>
</figure>
<h2>Which foods generate the most greenhouse gas emissions?</h2>
<p>Our framework makes it possible to compare how different food products and food-producing regions affect Earth’s climate. </p>
<p>Among animal-based foods, beef is the largest contributor to climate change. It generates 25% of total food emissions, followed by cow milk (8%) and pork (7%). </p>
<p>Rice is the largest contributor among plant-based foods, producing 12% of the total greenhouse gas emissions from the food sector, followed by wheat (5%) and sugarcane (2%). Rice stands out because it can grow in water, so many farmers flood their fields to kill weeds, creating ideal conditions for certain bacteria that emit methane.</p>
<p>This helps to explain why South and Southeast Asia have the greatest food-production-related emissions by region, producing 23% of the global total. This region is the only place where plant-based emissions are larger than animal-based emissions. South America is the second-largest emitter at 20%, and has the largest emissions from animal-based food, reflecting the dominance of ranching there.</p>
<p>Among individual countries, China, India and Indonesia have the highest emissions from plant-based food production, contributing 7%, 4%, and 2% respectively of global food-related greenhouse gas emissions. The countries with leading emissions from the production of animal-based foods are China (8%), Brazil (6%), the U.S. (5%) and India (4%).</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/420626/original/file-20210912-19-1c8830c.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A tractor spreads manure on a dirt field." src="https://images.theconversation.com/files/420626/original/file-20210912-19-1c8830c.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/420626/original/file-20210912-19-1c8830c.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/420626/original/file-20210912-19-1c8830c.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/420626/original/file-20210912-19-1c8830c.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/420626/original/file-20210912-19-1c8830c.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/420626/original/file-20210912-19-1c8830c.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/420626/original/file-20210912-19-1c8830c.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">Injecting manure into a field as fertilizer in Lawler, Iowa. Manure management is a major source of greenhouse gas emissions from livestock.</span>
<span class="attribution"><a class="source" href="https://newsroom.ap.org/detail/FactoryFarmFuror/f3f55abba4334a3a85303aa2f7d56e06/photo">AP Photo/Charlie Neibergall</a></span>
</figcaption>
</figure>
<h2>How food production affects land use</h2>
<p>Our framework also shows that raising animal-based foods consumes six times as much land as producing plant-based foods. </p>
<p>Worldwide, we estimate that humans are using 18 million square miles (4.6 billion hectares) of land to produce food – about 31% of Earth’s total land area, excluding areas covered by snow and ice. Of this, 30% is cropland and 70% is various types of grazing land. </p>
<p>Looking at how these areas are managed, we estimate that 13% of total agricultural land is being used to produce plant-based foods. The other 77% is being used to produce animal-based foods, including croplands that are growing animal feed and grazing lands. The remaining 10% is being used to raise other products, such as cotton, rubber and tobacco.</p>
<p>[<em>Over 100,000 readers rely on The Conversation’s newsletter to understand the world.</em> <a href="https://theconversation.com/us/newsletters/the-daily-3?utm_source=TCUS&utm_medium=inline-link&utm_campaign=newsletter-text&utm_content=100Ksignup">Sign up today</a>.]</p>
<p>Our study uses a consistent framework to provide a complete estimation of greenhouse gas emissions from food production and consumption, covering all food-related sub-sectors, at local, country, regional and global scales. It can help policymakers identify the plant- and animal-based food commodities that contribute the largest shares to climate change, and the higest-emitting sub-sectors at different locations. </p>
<p>Based on these results, governments, researchers and individuals can take actions to reduce emissions from high-emitting food commodities in different places. As <a href="https://www.business-standard.com/article/international/world-hunger-worsened-by-climate-change-conflict-un-secretary-general-121072601405_1.html">U.N. leaders have stated</a>, making food production more climate-friendly is essential to reduce hunger in a warming world.</p><img src="https://counter.theconversation.com/content/167623/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Atul Jain receives funding from the US Department of Energy.</span></em></p><p class="fine-print"><em><span>Xiaoming Xu 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>A new study provides a detailed way to calculate the climate impact of food production, which could lead to more sustainable farming policies and methods.Xiaoming Xu, Postdoctoral Research Associate in Atmospheric Sciences, University of Illinois at Urbana-ChampaignAtul Jain, Professor of Atmospheric Sciences, University of Illinois at Urbana-ChampaignLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1642202021-08-17T12:12:56Z2021-08-17T12:12:56ZOrganic food has become mainstream but still has room to grow<figure><img src="https://images.theconversation.com/files/415903/original/file-20210812-18-1klux43.jpg?ixlib=rb-1.1.0&rect=7%2C15%2C5184%2C3440&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Organic vegetables at the Center for Urban Agriculture at Fairview Gardens, Goleta, Calif.</span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/news-photo/the-center-for-urban-agriculture-at-fairview-gardens-the-news-photo/129369700">Citizen of the Planet/Education Images/Universal Images Group via Getty Images</a></span></figcaption></figure><figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/415881/original/file-20210812-18-1lepr89.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/415881/original/file-20210812-18-1lepr89.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/415881/original/file-20210812-18-1lepr89.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=255&fit=crop&dpr=1 600w, https://images.theconversation.com/files/415881/original/file-20210812-18-1lepr89.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=255&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/415881/original/file-20210812-18-1lepr89.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=255&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/415881/original/file-20210812-18-1lepr89.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=321&fit=crop&dpr=1 754w, https://images.theconversation.com/files/415881/original/file-20210812-18-1lepr89.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=321&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/415881/original/file-20210812-18-1lepr89.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=321&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="attribution"><a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
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</figure>
<p>Organic food once was viewed as a niche category for health nuts and hippies, but today it’s a routine choice for millions of Americans. For years following passage of the <a href="https://www.ams.usda.gov/sites/default/files/media/Organic%20Foods%20Production%20Act%20of%201990%20%28OFPA%29.pdf">Organic Foods Production Act of 1990</a>, which established national organic standards, consumers had to seek out organic products at food co-ops and farmers markets. Today over half of organic sales are in conventional grocery store chains, club stores and supercenters; Walmart, Costco, Kroger, Target and Safeway are the <a href="https://www.thebalancesmb.com/organic-retailers-in-north-america-2011-2538129">top five organic retailers</a>. </p>
<p>Surveys show that <a href="https://ota.com/organic-market-overview/organic-purchasing">82% of Americans buy some organic food</a>, and availability has improved. So why do overall organic sales add up to a mere <a href="https://www.foodbeverageinsider.com/market-trends-analysis/us-organic-sales-grow-record-high-62-billion-2020">6%</a> of all food sold in the U.S.? And since <a href="https://doi.org/10.1038/s41467-017-01410-w">organic farming has many benefits</a>, including conserving soil and water and reducing use of synthetic chemicals, can its share grow?</p>
<p>One issue is price. On average, <a href="https://www.ams.usda.gov/mnreports/wa_lo101.txt">organic food costs 20% more</a> than conventionally produced food. Even hardcore organic shoppers like me sometimes bypass it due to cost.</p>
<p>Some budget-constrained shoppers may restrict their organic purchases to foods they are especially concerned about, such as fruits and vegetables. Organic produce carries <a href="https://www.washingtonpost.com/lifestyle/food/the-truth-about-organic-produce-and-pesticides/2018/05/18/8294296e-5940-11e8-858f-12becb4d6067_story.html">far fewer pesticide residues</a> than conventionally grown versions. </p>
<p>Price matters, but let’s dig deeper. Increasing organic food’s market share will require growing larger quantities and more diverse organic products. This will require more organic farmers than the U.S. currently has. </p>
<p>There are some <a href="https://downloads.usda.library.cornell.edu/usda-esmis/files/5712m6524/tq57pj927/rx914h75j/fnlo0221.pdf">2 million farms in the U.S.</a>. Of them, <a href="https://www.nass.usda.gov/Publications/Highlights/2020/census-organics.pdf">only 16,585 are organic</a> – less than 1%. They occupy <a href="https://www.nass.usda.gov/Publications/AgCensus/2017/Online_Resources/Organics/organics_1_001%20_001.pdf">5.5 million acres</a>, which is a small fraction of overall U.S. agricultural land. Roughly two-thirds of U.S. farmland is dedicated to <a href="https://www.bloomberg.com/graphics/2018-us-land-use/">growing animal feed and biofuel feedstocks like corn and soybeans</a>, rather than food for people.</p>
<p>In my view, converting more agricultural land to organic food production should be a national goal. Organic farmers produce healthy food, promote soil health and protect watersheds. Ruminant animals like dairy cows when raised organically <a href="https://www.ams.usda.gov/sites/default/files/media/NOP-UnderstandingOrganicPastureRule.pdf">must graze on pasture</a> for at least 120 days each year, which reduces their methane emissions. </p>
<p>The list of <a href="https://rodaleinstitute.org/science/farming-systems-trial/">climate and environmental benefits</a> associated with organic is long. Organic farming consumes 45% less energy than conventional production, mainly because it doesn’t use nitrogen fertilizers. And it emits 40% less greenhouse gases because organic farmers practice crop rotation, use cover crops and composting, and eliminate fossil fuel-based inputs. </p>
<p>The vast majority of organic farms are small or midsized, both in terms of gross sales and acreage. Organic farmers are <a href="https://www.nass.usda.gov/Publications/AgCensus/2017/Online_Resources/Organics_Tabulation/organictab.pdf">younger on average than conventional farmers</a>. </p>
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<p>Starting small makes sense for beginning farmers, and organic price premiums allow them to survive on smaller plots of land. But first they need to go through a tough three-year transition period to cleanse the land. </p>
<p>During this time they are ineligible to label products as organic, but must follow organic standards, including forgoing use of harmful chemicals and learning how to manage ecosystem processes. This typically results in short-term yield declines. Many farmers fail along the way.</p>
<p>The transition period is just one of many <a href="https://www.nass.usda.gov/Publications/AgCensus/2017/Online_Resources/Organics/organics_1_024%20_024.pdf">challenges for organic farmers</a>. Greater federal government support could help. In a recent report, Arizona State University’s <a href="https://sustainability-innovation.asu.edu/food/">Swette Center for Sustainable Food Systems</a>, which I direct, identified actions the Biden administration can take within existing budgets and laws to <a href="https://sustainability-innovation.asu.edu/food/wp-content/uploads/sites/39/2021/06/Organic-Report-2021-2.pdf">realize the untapped promise of organic agriculture</a>. </p>
<p>Current <a href="https://www.ams.usda.gov/sites/default/files/media/USDASupportforOrganicFarmsandBusinessesFactSheet.pdf">USDA assistance for organic producers</a> is paltry, especially given the billions of dollars that the agency spends annually in support of agriculture. Two-thirds of farm subsidy dollars go to the <a href="https://www.ewg.org/interactive-maps/2021-farm-subsidies-ballooned-under-trump/">top 10% richest farms</a>. </p>
<p>Our report recommends dedicating 6% of USDA spending to supporting the organic sector, a figure that reflects its market share. As an example, in 2020 the agency spent about $55 million on research directly pertinent to organic agriculture within its $3.6 billion Research, Education and Economics mission area. A 6% share of that budget would be $218 million for developing things like better ways of controlling pests by using natural predators instead of chemical pesticides. </p>
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<p>Organic food’s higher price includes costs associated with practices like forgoing use of harmful pesticides and improving animal welfare. A growing number of food systems scholars and practitioners are calling for use of a methodology called <a href="https://www.taylorfrancis.com/books/oa-edit/10.4324/9781003050803/true-cost-accounting-food-barbara-gemmill-herren-lauren-baker-paula-daniels">True Cost Accounting</a>, which they believe reveals the full costs and benefits of food production. </p>
<p>[<em>Over 100,000 readers rely on The Conversation’s newsletter to understand the world.</em> <a href="https://theconversation.com/us/newsletters/the-daily-3?utm_source=TCUS&utm_medium=inline-link&utm_campaign=newsletter-text&utm_content=100Ksignup">Sign up today</a>.]</p>
<p>According to an analysis by the Rockefeller Foundation, American consumers spend $1.1 trillion yearly on food, but the <a href="https://www.rockefellerfoundation.org/report/true-cost-of-food-measuring-what-matters-to-transform-the-u-s-food-system/">true cost of that food is $3.2 trillion</a> when all impacts like water pollution and farmworker health are factored in. Looked at through a True Cost Accounting lens, I see organic as a good deal.</p><img src="https://counter.theconversation.com/content/164220/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Kathleen Merrigan directs the Swette Center for Sustainable Food Systems at Arizona State University, which receives funding from the Organic Trade Association. She is co-director of a project on inadvertent chemical contamination of organic crops funded by the US Department of Agriculture. Merrigan is a member of the Advisory Committee for the Organic Farming Research Foundation. She also is an advisor to S2G Ventures and a Venture Partner at Astanor Ventures, two agtech firms that have some organic companies in their much broader portfolios. As a US Senate staffer, Merrigan drafted the Organic Foods Production Act of 1990. She has served on the National Organic Standards Board, as Administrator of the USDA Agricultural Marketing Service and as Deputy Secretary of Agriculture.
</span></em></p>Four out of five Americans regularly buy some kind of organic food. An expert on the industry says more federal support could greatly expand organic farming and its environmental benefits.Kathleen Merrigan, Executive Director, Swette Center for Sustainable Food Systems, Arizona State UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1646802021-08-04T12:33:04Z2021-08-04T12:33:04ZBiden restores roadless protection to the Tongass, North America’s largest rainforest<figure><img src="https://images.theconversation.com/files/506676/original/file-20230126-23261-4wm1yv.jpg?ixlib=rb-1.1.0&rect=14%2C7%2C4977%2C3315&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">A bald eagle on Baranof Island in Alaska's Tongass National Forest.</span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/news-photo/bald-eagle-is-sitting-on-a-moss-covered-tree-in-the-forest-news-photo/1176547464">Wolfgang Kaehler/LightRocket via Getty Images</a></span></figcaption></figure><p>Ask people to find the world’s rainforests on a globe, and most will probably point to South America. But North America has rainforests too – and like their tropical counterparts, these <a href="https://www.wilderness.org/articles/blog/hidden-treasures-americas-rainforests">temperate rainforests</a> are ecological treasures.</p>
<p>The Biden administration finalized a rule on Jan. 25, 2023, that <a href="https://www.usda.gov/media/press-releases/2023/01/25/biden-harris-administration-finalizes-protections-tongass-national">restores roadless protection</a> to more than 9 million acres of the <a href="https://www.fs.usda.gov/tongass/">Tongass National Forest</a>, keeping this land free from road-building and logging. The Tongass is the largest intact temperate rainforest in the world and the biggest U.S. national forest. It spreads over more than 26,000 square miles (67,340 square kilometers) – roughly the size of West Virginia – and covers most of southeast Alaska. It has thousands of watersheds and fjords, and more than a thousand forested islands. </p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/413851/original/file-20210729-25-17y9up4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Map overlaying Alaska on the continental U.S." src="https://images.theconversation.com/files/413851/original/file-20210729-25-17y9up4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/413851/original/file-20210729-25-17y9up4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=350&fit=crop&dpr=1 600w, https://images.theconversation.com/files/413851/original/file-20210729-25-17y9up4.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=350&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/413851/original/file-20210729-25-17y9up4.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=350&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/413851/original/file-20210729-25-17y9up4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=439&fit=crop&dpr=1 754w, https://images.theconversation.com/files/413851/original/file-20210729-25-17y9up4.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=439&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/413851/original/file-20210729-25-17y9up4.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=439&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Alaska’s national forests, the Chugach and the Tongass, compared with the lower 48 states.</span>
<span class="attribution"><a class="source" href="https://www.fs.fed.us/wildflowers/regions/alaska/index.php">USFS</a></span>
</figcaption>
</figure>
<p>For over 20 years, the Tongass has been at the center of political battles over two key conservation issues: <a href="https://www.scientificamerican.com/article/are-old-growth-forests/">old-growth logging</a> and designating large forest zones as <a href="https://islandpress.org/books/roadless-rules">roadless areas</a> to prevent development. As a <a href="https://scholar.google.com/citations?user=J2KWqAoAAAAJ&hl=en">scientist specializing in forest ecosystems</a>, I see protecting the Tongass as the kind of bold action that’s needed to address <a href="https://www.un.org/sustainabledevelopment/blog/2021/06/tackling-biodiversity-climate-crises-together-and-their-combined-social-impacts/">climate change and biodiversity loss</a>.</p>
<h2>An ecological gem</h2>
<p>The Tongass as we know it today began forming at the end of the <a href="https://theconversation.com/small-climate-changes-can-have-devastating-local-consequences-it-happened-in-the-little-ice-age-164916">Little Ice Age</a> in the mid-1700s, which left much of what is now southern Alaska as barren land. Gradually, the area repopulated with plants and animals to become a swath of diverse, rich old-growth forests. President Theodore Roosevelt designated the Tongass as a forest reserve in 1902, and then as a national forest in 1907. </p>
<p>The Tongass is the <a href="https://www.indianz.com/News/2019/10/21/respect-alaska-tribes-rights-on-the-tong.asp">traditional homeland</a> of the Tlingit, Haida and Tsimshian people. It is named for the Tongass group of the Tlingit people, who have continuously occupied the area for <a href="https://www.fs.usda.gov/main/tongass/about-forest">over 10,000 years</a>. </p>
<p>Alaska Natives relied on the forest’s rich diversity of plants and animals for their survival and traditions. Today the Tongass has abundant populations of animals that have become uncommon in other parts of the U.S., such as brown bears and wolves. </p>
<p>Most of the <a href="https://www.fs.usda.gov/inside-fs/tongass-state-alaska-work-together-maintain-water-quality-all">900 watersheds</a> within the Tongass are in near-natural condition. This ensures that they can provide habitat for many wild species and recover from or adapt to stresses, such as warmer temperatures due to climate change. They support salmon that spawn in the forest’s creeks and rivers, <a href="https://www.adfg.alaska.gov/static/home/library/pdfs/ak_wild_salmon.pdf">providing food for bears, eagles and other predators</a>. Such ecosystems are incredibly rare around the world today. </p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/wX5c_-ln9Pk?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">The Tongass National Forest is home to bears, bald eagles and five species of salmon.</span></figcaption>
</figure>
<h2>How roads threaten forests</h2>
<p>Intact old-growth forests, with trees hundreds of years old, are essential for carbon storage, biodiversity and climate resilience. They have fully developed root systems that can reach water in deep soils, and are more resistant than young forests to drought, fire, insects and strong winds – effects that are all <a href="https://science2017.globalchange.gov/chapter/8/">likely to increase with climate change</a>. </p>
<p>Because old-growth forests have accumulated massive amounts of carbon in their trees and soils over centuries, protecting them is <a href="https://theconversation.com/keeping-trees-in-the-ground-where-they-are-already-growing-is-an-effective-low-tech-way-to-slow-climate-change-154618">an important strategy for curbing climate change</a>. Today, however, scientists estimate that logging, agriculture and urban development have left only <a href="https://www.scientificamerican.com/article/are-old-growth-forests/">6%</a> to <a href="http://dx.doi.org/10.1126/sciadv.1600821">14%</a> of the forest area in the U.S. intact. And only <a href="https://doi.org/10.2737/WO-GTR-91">7% of total U.S. forest area</a> is more than a century old. </p>
<p><a href="https://theconversation.com/why-people-are-risking-arrest-to-join-old-growth-logging-protests-on-vancouver-island-161550">Old-growth logging is controversial</a> because intact forests are so rare. And forest losses often start when roads are cut through them to access timber. The roads are effectively long clear-cuts across the landscape. </p>
<p>Building roads through moist temperate forests can make it easier for warm air, wind and sunlight to penetrate from the edges to the interior, drying soil, mosses and ferns. It also provides entry points for invasive plants carried in by vehicles. </p>
<p>And roads’ negative effects extend beyond the actual driving surface. A road 30 feet (9 meters) wide may influence an additional 80 to 100 feet (25 to 30 meters) of adjacent land because of land disturbance during construction and wide buffer zones created for vehicle safety.</p>
<p>Road building can harm animals like <a href="https://www.sierraclub.org/sierra/new-roads-tongass-national-forest-could-harm-bears">brown bears</a> through collisions with vehicles and increased poaching and trapping. In the Tongass, a strip a quarter-mile (0.4 kilometer) wide on each side of the highway system is <a href="https://www.adfg.alaska.gov/static/regulations/wildliferegulations/pdfs/regulations_complete.pdf">closed to big game hunting</a>, but this mitigates only some of roads’ pervasive effects.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/413875/original/file-20210730-23-19atx1e.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Bulldozers grade land next to a gravel logging road." src="https://images.theconversation.com/files/413875/original/file-20210730-23-19atx1e.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/413875/original/file-20210730-23-19atx1e.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/413875/original/file-20210730-23-19atx1e.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/413875/original/file-20210730-23-19atx1e.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/413875/original/file-20210730-23-19atx1e.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/413875/original/file-20210730-23-19atx1e.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/413875/original/file-20210730-23-19atx1e.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">Upgrading a logging road into State Highway 43 on Prince of Wales Island in the Tongass National Forest.</span>
<span class="attribution"><a class="source" href="https://flic.kr/p/diZWsT">Jack Olen, USFS Alaska Region/Flickr</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<h2>Decades of controversy</h2>
<p>The controversy over roadless areas began in January 2001, when the Clinton administration adopted the <a href="https://www.fs.usda.gov/roadmain/roadless/2001roadlessrule">Roadless Area Conservation Rule</a>. This measure barred logging, timber sales, mining and road construction within inventoried roadless areas in most national forests across the U.S. About 9.2 million acres (37,231 square kilometers) of the Tongass – more than half of its area – were designated and managed as inventoried roadless areas. </p>
<p>This step launched <a href="https://eelp.law.harvard.edu/2020/05/alaska-roadless-rule/">20 years of debate and litigation</a>. The Bush and Trump administrations, supported by conservative Western state officials, sought to limit the roadless rule and exempt the Tongass from it. The Obama administration generally supported the rule and defended it in court.</p>
<p>In 2020, the Trump administration opened the Tongass to <a href="https://www.reuters.com/article/us-usa-alaska-logging-idINKBN27D2KV">extensive new logging, mining and road construction activities</a>. Critics, including environmental advocates and tribal governments, argued that Alaska’s economy was better served by <a href="https://insideclimatenews.org/news/26092020/roadless-rule-tongass-alaska-logging/">outdoor recreation and commercial fishing</a> than by clear-cutting its remaining old-growth forests. </p>
<p>Now, the Biden administration has restored protection for roadless areas of the Tongass. President Joe Biden has also issued an <a href="https://www.whitehouse.gov/briefing-room/presidential-actions/2022/04/22/executive-order-on-strengthening-the-nations-forests-communities-and-local-economies/">executive order</a> that calls for conserving mature and old-growth forests on federal land – although he <a href="https://insideclimatenews.org/news/15112022/cop27-deforestation-united-states-logging/">has not yet banned</a> logging in old-growth forests – and pledged to combat deforestation worldwide. </p>
<p><div data-react-class="Tweet" data-react-props="{"tweetId":"1415838613489729539"}"></div></p>
<h2>A strategic climate reserve</h2>
<p>New protection for the Tongass comes amid growing alarm over two converging environmental crises: climate change and accelerated extinctions of plant and animal species. In my view, protecting ecological treasures like the Tongass is a critical way to <a href="https://ipbes.net/sites/default/files/2021-06/2021_IPCC-IPBES_scientific_outcome_20210612.pdf">address both issues at once, as scientists have recommended</a>.</p>
<p>The southeastern and south-central regions of Alaska, which contain the Tongass and <a href="https://www.fs.usda.gov/chugach/">Chugach</a> national forests, store about 1 billion metric tons of carbon in live and dead tree biomass. This amount could increase by <a href="https://doi.org/10.3133/pp1826">27% by 2100</a> if the forest is allowed to continue to grow and accumulate carbon.</p>
<p>I believe the Tongass’ vast intactness, rich biodiversity and significant carbon storage make it an excellent choice as the first of a series of <a href="https://wild-heritage.org/wp-content/uploads/2021/03/scientistsignonTongass3-17-21.pdf">strategic climate reserves</a> – areas that scientists have proposed setting aside to protect large carbon sinks and biodiversity of plant and animal species. U.S. old-growth forests are disappearing rapidly, but with smart management they can deliver ecological benefits for decades to come.</p><img src="https://counter.theconversation.com/content/164680/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>The Tongass National Forest in Alaska, a focus of political battles over old-growth logging and road-building in forests for decades, has received new protection from the Biden administration.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/1632502021-07-19T20:09:24Z2021-07-19T20:09:24Z‘One of the most damaging invasive species on Earth’: wild pigs release the same emissions as 1 million cars each year<figure><img src="https://images.theconversation.com/files/407806/original/file-20210623-25-t6gb84.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C5439%2C3615&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><a class="source" href="https://pixabay.com/photos/wild-wild-boar-pig-nature-forest-5325555/">Pixabay</a></span></figcaption></figure><p>Whether you call them feral pigs, boar, swine, hogs, or even razorbacks, wild pigs are one of the <a href="https://link.springer.com/article/10.1007/s10530-012-0229-6">most damaging invasive species</a> on Earth, and they’re notorious for <a href="https://theconversation.com/feral-pigs-harm-wildlife-and-biodiversity-as-well-as-crops-120066">damaging agriculture and native wildlife</a>. </p>
<p>A big reason they’re so harmful is because they <a href="https://feralhogs.extension.org/rooting-behavior-of-feral-hogs/">uproot soil</a> at vast scales, like tractors ploughing a field. Our <a href="https://doi.org/10.1111/gcb.15769">new research</a>, published today, is the first to calculate the global extent of this and its implications for carbon emissions.</p>
<p>Our findings were staggering. We discovered the cumulative area of soil uprooted by wild pigs is likely the same area as Taiwan. This releases 4.9 million tonnes of carbon dioxide each year — the same as one million cars. The majority of these emissions occur in Oceania. </p>
<p>A <a href="https://www.nature.com/scitable/knowledge/library/soil-carbon-storage-84223790/">huge portion of Earth’s carbon</a> is stored in soil, so releasing even a small fraction of this into the atmosphere can have a huge impact on climate change. </p>
<h2>The problem with pigs</h2>
<p>Wild pigs (<em>Sus scrofa</em>) are native throughout much of Europe and Asia, but today they live on every continent except Antarctica, making them one of the most <a href="https://www.smithsonianmag.com/science-nature/the-worlds-worst-invasive-mammals-77341057/?page=13">widespread invasive mammals</a> on the planet. An estimated <a href="https://www.publish.csiro.au/zo/zo20077">three million</a> wild pigs live in Australia alone.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/411810/original/file-20210719-23-1t0qhng.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A herd of wild pigs" src="https://images.theconversation.com/files/411810/original/file-20210719-23-1t0qhng.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/411810/original/file-20210719-23-1t0qhng.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=409&fit=crop&dpr=1 600w, https://images.theconversation.com/files/411810/original/file-20210719-23-1t0qhng.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=409&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/411810/original/file-20210719-23-1t0qhng.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=409&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/411810/original/file-20210719-23-1t0qhng.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=513&fit=crop&dpr=1 754w, https://images.theconversation.com/files/411810/original/file-20210719-23-1t0qhng.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=513&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/411810/original/file-20210719-23-1t0qhng.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=513&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Wild pigs are one of the most widespread invasive animals on Earth.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<p>It’s estimated that wild pigs destroy more than <a href="https://feralpigs.com.au/the-plan/#ActionPlan">A$100 million</a> (US$74 million) worth of crops and pasture each year in Australia, and more than <a href="https://www.sciencedirect.com/science/article/pii/S0261219420300387">US$270 million</a> (A$366 million) in just 12 states in the USA. </p>
<p>Wild pigs have also been found to directly threaten 672 vertebrate and plant species across <a href="https://www.nature.com/articles/s41598-021-92691-1">54 different countries</a>. This includes imperilled Australian ground frogs, tree frogs and multiple orchid species, as pigs destroy their habitats and prey on them.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/t22hkF0A6h8?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
</figure>
<p>Their geographic range is <a href="https://www.nature.com/articles/srep44152">expected to expand</a> in the coming decades, suggesting their threats to food security and biodiversity will likely worsen. But here, let’s focus on their contribution to global emissions. </p>
<h2>Their carbon hoofprint</h2>
<p>Previous research has highlighted the potential contribution of wild pigs to greenhouse gas emissions, but only at local scales. </p>
<p>One such study was conducted for three years in hardwood forests of Switzerland. The researchers found wild pigs caused soil carbon emissions to increase by around <a href="https://link.springer.com/content/pdf/10.1007/s00442-010-1665-6.pdf">23% per year</a>. </p>
<p>Similarly, a study in the Jigong Mountains National Nature Reserve in China found soil emissions <a href="https://www.sciencedirect.com/science/article/pii/S0378112719325010">increased by more than 70%</a> per year in places disturbed by wild pigs.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/411811/original/file-20210719-21-fjl4em.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/411811/original/file-20210719-21-fjl4em.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/411811/original/file-20210719-21-fjl4em.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/411811/original/file-20210719-21-fjl4em.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/411811/original/file-20210719-21-fjl4em.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/411811/original/file-20210719-21-fjl4em.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/411811/original/file-20210719-21-fjl4em.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/411811/original/file-20210719-21-fjl4em.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">Wild pigs turn over 36,214 to 123,517 square kilometres of soil each year.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<p>To find out what the impact was on a global scale, we ran 10,000 simulations of <a href="https://www.nature.com/articles/srep44152">wild pig population sizes</a> in their non-native distribution, including in the Americas, Oceania, Africa and parts of Southeast Asia. </p>
<p>For each simulation, we determined the amount of soil they would disturb using <a href="https://www.sciencedirect.com/science/article/pii/S0006320701001859">another model from a different study</a>. Lastly, we used local case studies to calculate the minimum and maximum amount of wild pig-driven carbon emissions. </p>
<p>And we estimate the soil wild pigs uproot worldwide each year is likely between 36,214 and 123,517 square kilometres — or between the sizes of Taiwan and England. </p>
<p>Most of this soil damage and associated emissions occur in Oceania due to the large distribution of wild pigs there, and the amount of carbon stored in the soil in this region.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/feral-pigs-harm-wildlife-and-biodiversity-as-well-as-crops-120066">Feral pigs harm wildlife and biodiversity as well as crops</a>
</strong>
</em>
</p>
<hr>
<h2>So how exactly does disturbing soil release emissions?</h2>
<p>Wild pigs use their tough snouts to excavate soil in search of plant parts such as roots, fungi and invertebrates. This “ploughing” behaviour commonly disturbs soil at a <a href="https://esajournals.onlinelibrary.wiley.com/doi/full/10.1890/03-5142">depth of about five to 15 centimetres</a>, which is roughly the same depth as <a href="https://www.sciencedirect.com/science/article/pii/S0167198706001590">crop tilling</a> by farmers.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/409419/original/file-20210702-28-v6bz2n.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/409419/original/file-20210702-28-v6bz2n.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=346&fit=crop&dpr=1 600w, https://images.theconversation.com/files/409419/original/file-20210702-28-v6bz2n.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=346&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/409419/original/file-20210702-28-v6bz2n.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=346&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/409419/original/file-20210702-28-v6bz2n.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=435&fit=crop&dpr=1 754w, https://images.theconversation.com/files/409419/original/file-20210702-28-v6bz2n.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=435&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/409419/original/file-20210702-28-v6bz2n.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=435&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Wild pigs uproot soil in search of food, such as invertebrates and plant roots.</span>
<span class="attribution"><span class="source">University of Kentucky, Department of Forestry and Natural Resources, Forestry Extension.</span></span>
</figcaption>
</figure>
<p>Because wild pigs are <a href="https://pestsmart.org.au/toolkit-resource/feral-pig-biology-ecology-and-behaviour/">highly social</a> and often feed in large groups, they can completely destroy a small paddock in a short period. This makes them a formidable foe to the organic carbon stored in soil. </p>
<p>In general, soil organic carbon is the balance between organic matter input into the soil (such as fungi, animal waste, root growth and leaf litter) versus outputs (such as decomposition, respiration and erosion). This balance is an <a href="https://rangelandswa.com.au/wp-content/uploads/2017/05/SoilOrganicCarbon_Factsheet_Jan16.pdf">indicator of soil health</a>. </p>
<p>When soils are disturbed, whether from ploughing a field or from an animal burrowing or uprooting, carbon is released into the atmosphere as a greenhouse gas. </p>
<p>This is because digging up soil exposes it to oxygen, and oxygen promotes the rapid growth of microbes. These newly invigorated microbes, in turn, break down the organic matter containing carbon. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/411813/original/file-20210719-23-1rjsf4l.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/411813/original/file-20210719-23-1rjsf4l.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/411813/original/file-20210719-23-1rjsf4l.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=384&fit=crop&dpr=1 600w, https://images.theconversation.com/files/411813/original/file-20210719-23-1rjsf4l.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=384&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/411813/original/file-20210719-23-1rjsf4l.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=384&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/411813/original/file-20210719-23-1rjsf4l.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=482&fit=crop&dpr=1 754w, https://images.theconversation.com/files/411813/original/file-20210719-23-1rjsf4l.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=482&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/411813/original/file-20210719-23-1rjsf4l.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=482&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Wild pigs have a rapid breeding rate, which makes controlling populations difficult.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<h2>Tough and cunning</h2>
<p>Wild pig control is <a href="https://www.theatlantic.com/science/archive/2021/05/poison-feral-hogs/618902/">incredibly difficult and costly</a> due to their cunning behaviour, rapid breeding rate, and overall tough nature. </p>
<p>For example, wild pigs have been known to <a href="https://pestsmart.org.au/toolkit-resource/trapping-of-feral-pigs/">avoid traps</a> if they had been previously caught, and they are skilled at <a href="https://bioone.org/journals/wildlife-biology/volume-19/issue-1/12-027/Effects-of-hunting-on-wild-boar-Sus-scrofa-behaviour/10.2981/12-027.full">changing their behaviour</a> to avoid hunters.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/dig-this-a-tiny-echidna-moves-8-trailer-loads-of-soil-a-year-helping-tackle-climate-change-155947">Dig this: a tiny echidna moves 8 trailer-loads of soil a year, helping tackle climate change</a>
</strong>
</em>
</p>
<hr>
<p>In Australia, management efforts include <a href="https://www.abc.net.au/news/rural/2021-06-11/inside-australias-biggest-boar-hunt-jambin/100205390">coordinated hunting events</a> to slow the spread of wild pig populations. Other techniques include setting traps and installing fences to prevent wild pig expansion, or aerial control programs. </p>
<p>Some of these control methods can also cause substantial carbon emissions, such as using helicopters for aerial control and other vehicles for hunting. Still, the long-term benefits of wild pig reduction may far outweigh these costs. </p>
<p>Working towards reduced global emissions is no simple feat, and <a href="https://doi.org/10.1111/gcb.15769">our study</a> is another tool in the toolbox for assessing the threats of this widespread invasive species. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/tiny-game-of-thrones-the-workers-of-yellow-crazy-ants-can-act-like-lazy-wannabe-queens-so-we-watched-them-fight-158426">Tiny Game of Thrones: the workers of yellow crazy ants can act like lazy wannabe queens. So we watched them fight</a>
</strong>
</em>
</p>
<hr>
<img src="https://counter.theconversation.com/content/163250/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Christopher O'Bryan receives funding from the Invasive Animals Cooperative Research Centre in Australia and the Australian Research Council (ARC).</span></em></p><p class="fine-print"><em><span>Eve McDonald-Madden receives funding from Australian Research Council. </span></em></p><p class="fine-print"><em><span>Matthew H. Holden receives funding from the Australian Research Council (ARC). </span></em></p><p class="fine-print"><em><span>Nicholas R Patton receives funding from the Australian Research Council (ARC), and the Australia's Nuclear Science and Technology Organisation (ANSTO). </span></em></p><p class="fine-print"><em><span>Jim Hone 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>Wild pigs are on every continent, except Antarctica. All up, they likely turn over the the same amount of soil as the area of Taiwan.Christopher J. O'Bryan, Postdoctoral Research Fellow, School of Earth and Environmental Sciences, The University of QueenslandEve McDonald-Madden, Associate professor, The University of QueenslandJim Hone, Emeritus professor, University of CanberraMatthew H. Holden, Lecturer, School of Mathematics and Physics, The University of QueenslandNicholas R Patton, Ph.D. Candidate, University of CanterburyLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1602432021-06-30T12:12:33Z2021-06-30T12:12:33ZTo make agriculture more climate-friendly, carbon farming needs clear rules<figure><img src="https://images.theconversation.com/files/408481/original/file-20210626-17-3d0f70.jpg?ixlib=rb-1.1.0&rect=0%2C4%2C2828%2C1881&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Soybeans sprout on an Illinois farm through corn stubble left on an unplowed field from the previous season – an example of no-till farming.</span> <span class="attribution"><a class="source" href="https://flic.kr/p/dgETmg">Paige Buck, USDA/Flickr</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span></figcaption></figure><p>As the effects of <a href="https://climate.nasa.gov/effects/">climate change</a> intensify and <a href="https://doi.org/10.1002/wcc.621">paths for limiting global warming narrow</a>, politicians, media and environmental advocates have rallied behind “carbon farming” as a mutually beneficial strategy for society, the environment and farmers.</p>
<p>Agriculture covers <a href="https://ourworldindata.org/environmental-impacts-of-food">more than half of Earth’s terrestrial surface</a> and contributes <a href="https://www.ipcc.ch/srccl/chapter/chapter-5/">roughly one-third</a> of global greenhouse gas emissions. Paying farmers to restore <a href="https://doi.org/10.1073/pnas.1706103114">carbon-depleted</a> soils offers a tantalizing opportunity for <a href="https://doi.org/10.1038/s41893-020-0491-z">a natural climate solution</a> that could help nations to meet their commitments under the international <a href="https://unfccc.int/process-and-meetings/the-paris-agreement/the-paris-agreement">Paris climate agreement</a> to stabilize global warming below 2 degrees Celsius. </p>
<p>An international initiative called “<a href="https://www.4p1000.org">4 per 1000</a>,” launched at the <a href="https://www.cop21paris.org/about/cop21">2015 Paris climate conference</a>, showed that increasing soil carbon worldwide by just 0.4% yearly could <a href="https://doi.org/10.1016/j.still.2017.12.002">offset that year’s new growth in carbon dioxide emissions from fossil fuel emissions</a>. </p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/408943/original/file-20210629-24-1lvhasn.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Pig sunbathing in pasture." src="https://images.theconversation.com/files/408943/original/file-20210629-24-1lvhasn.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/408943/original/file-20210629-24-1lvhasn.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=491&fit=crop&dpr=1 600w, https://images.theconversation.com/files/408943/original/file-20210629-24-1lvhasn.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=491&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/408943/original/file-20210629-24-1lvhasn.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=491&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/408943/original/file-20210629-24-1lvhasn.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=617&fit=crop&dpr=1 754w, https://images.theconversation.com/files/408943/original/file-20210629-24-1lvhasn.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=617&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/408943/original/file-20210629-24-1lvhasn.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=617&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 free-range pig at the Stone Brns Center for Food and Agriculture in New York. Raising livestock and crops together can boost soil carbon through the animals’ grazing patterns and natural manure distribution.</span>
<span class="attribution"><span class="source">Francesca Cotrufo</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<p>Research shows that farmers and <a href="https://doi.org/10.1038/ncomms7995">ranchers</a> can also make their operations <a href="https://doi.org/10.1088/1748-9326/abe492">more resilient</a> to <a href="https://doi.org/10.1016/j.agsy.2021.103085">increasingly variable weather</a> by adopting practices that promote soil carbon sequestration. This prospect led us to <a href="https://www.research.colostate.edu/cip/scsc/">establish a center</a> at Colorado State University that develops and implements <a href="https://scholar.google.com/citations?user=i4i0ZvoAAAAJ&hl=en">soil-based</a> <a href="https://scholar.google.com/citations?user=HRySep8AAAAJ&hl=en">solutions</a> to <a href="https://scholar.google.com/citations?user=Jg8EQ28AAAAJ&hl=en">climate</a> <a href="https://scholar.google.com/citations?user=Prw0xGgAAAAJ&hl=en">change</a>. </p>
<p>While many policy options exist to <a href="https://www.oecd-ilibrary.org/sites/16af156c-en/index.html?itemId=/content/component/16af156c-en">reduce emissions from agricuture</a>, carbon farming has sparked <a href="https://www.politico.com/news/2021/06/24/senate-farmers-carbon-agriculture-496029">bipartisan U.S. legislation</a> and attracted <a href="https://www.greenbiz.com/article/how-carbon-smart-farming-catalyzing-big-bucks-needed-transform-way-america-eats">investors’ attention</a>. Critics <a href="https://www.wri.org/insights/insider-further-explanation-potential-contribution-soil-carbon-sequestration-working">question</a> its true potential, however. Some environment and justice advocacy groups argue that paying farmers <a href="https://modernfarmer.com/2021/04/environmental-groups-call-bidens-carbon-bank-plan-a-scam/">won’t do much to increase soil carbon</a>, and could allow polluting industries such as manufacturing to avoid necessary emission reductions by buying soil carbon credits from farmers instead.</p>
<p>Given the momentum behind carbon farming as a climate change mitigation strategy, we believe now is the time to establish clear standards that ensure that only real net changes in carbon receive financial rewards.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/AY9YVwJZDvw?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Increasing carbon storage in soil can help stabilize the climate and support food production.</span></figcaption>
</figure>
<h2>Carbon farming basics</h2>
<p>As plants grow, they pull carbon from the atmosphere, and soil soaks it up and stores it. The amount of carbon stored <a href="https://doi.org/10.1016/j.still.2013.10.002">varies significantly</a> across soil type and climate. </p>
<p>Traditional farming methods that sequester carbon <a href="https://doi.org/10.1016/0167-8809(92)90095-S">have existed for millennia</a>. For example, minimizing soil disturbance through <a href="https://doi.org/10.2136/sssaj2013.09.0422">no-till farming</a> reduces carbon loss to the atmosphere. <a href="https://doi.org/10.3389/fsufs.2021.564900">Diversifying crops</a> and planting <a href="https://doi.org/10.1007/s13593-011-0056-7">legumes</a>, <a href="https://doi.org/10.1093/biosci/biy014">perennials</a> and <a href="https://esajournals.onlinelibrary.wiley.com/doi/10.1002/eap.2278">cover crops</a> returns more carbon to the soil, and sustains soil microbes that <a href="https://theconversation.com/to-restore-our-soils-feed-the-microbes-79616">play key roles in carbon storage</a>. </p>
<p>Another climate-friendly strategy is raising livestock and crops together. Rotating cows among pastures allows grasses to recover from grazing, and the animals’ manure and the impacts of their grazing <a href="https://doi.org/10.1016/j.jenvman.2021.112409">regenerate carbon in soils</a>. </p>
<p>Some farmers use these practices, which often are called “<a href="https://theconversation.com/regenerative-agriculture-can-make-farmers-stewards-of-the-land-again-110570">regenerative agriculture</a>,” particularly in <a href="https://www.chelseagreen.com/product/farming-while-black/">Black</a> and <a href="https://www.nativefoodsystems.org/">Indigenous communities</a> that have been <a href="https://flexpub.com/preview/dispossession">excluded from access to capital and government subsidies</a>. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/408941/original/file-20210629-16-1okuhx3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Cross section of prairie soil with deep roots." src="https://images.theconversation.com/files/408941/original/file-20210629-16-1okuhx3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/408941/original/file-20210629-16-1okuhx3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/408941/original/file-20210629-16-1okuhx3.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/408941/original/file-20210629-16-1okuhx3.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/408941/original/file-20210629-16-1okuhx3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/408941/original/file-20210629-16-1okuhx3.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/408941/original/file-20210629-16-1okuhx3.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">The deep roots of Kernza, a perennial grain, reduce erosion, help the plant tolerate drought and add soil carbon deeper in the ground than shorter-rooted annual grains. Kernza, the first commercially viable perennial grain in the U.S., was developed by The Land Institute, based in Salina, Kansas.</span>
<span class="attribution"><span class="source">Francesca Cotrufo</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<h2>Soil: A low-cost solution</h2>
<p>Increasing soil carbon through techniques like no-till is relatively inexpensive. Studies estimate that carbon farming costs <a href="https://doi.org/10.1038/s41893-020-0491-z">US$10-$100 per ton of CO2 removed</a>, compared with $100-$1,000 per ton for technologies that <a href="https://www.iea.org/reports/direct-air-capture">mechanically remove carbon from the air</a>.</p>
<p>Carbon farming is also a potential revenue stream for farmers and ranchers, who can <a href="https://www.wisfarmer.com/story/news/2021/04/18/what-farmers-should-know-selling-carbon-credits/7280044002/">sell the credits they earn in carbon markets</a>. Large-scale greenhouse gas emitters, such as manufacturers, purchase these credits to offset their own emissions.</p>
<p>Companies such as <a href="https://www.indigoag.com/pages/news/first-companies-commit-to-purchasing-verified-agricultural-carbon-credits">IndigoAg</a> and <a href="https://locusag.com/shopify-will-be-first-high-volume-corporate-buyer-of-carbon-credits-from-a-us-carbonnow-farmer/">Nori</a> are already facilitating payments to farmers for carbon credits. And on June 24, 2021, the U.S. Senate passed the <a href="https://www.congress.gov/bill/117th-congress/senate-bill/1251/cosponsors?r=46&s=1&searchResultViewType=expanded">Growing Climate Solutions Act of 2021</a> by a vote of 92-8. The bill would authorize the U.S. Department of Agriculture to help farmers, ranchers and private forest landowners participate in carbon markets.</p>
<p>So far, however, there are no universal standards for measuring, reporting or verifying agricultural carbon credits. Here are the questions we see as top priorities.</p>
<p><div data-react-class="Tweet" data-react-props="{"tweetId":"1352640593151758336"}"></div></p>
<h2>Assessing carbon storage</h2>
<p>One major challenge is that soils absorb varying amounts of carbon depending on depth, texture and mineral content. While <a href="https://doi.org/10.3389/fclim.2019.00008">certain practices increase carbon storage</a>, quantifying how much is stored and for how long is critical for assigning dollar values to them. The <a href="https://doi.org/10.1111/gcb.15613">markets and practices</a> that work in different locations also vary widely.</p>
<p>Some scientific models offer <a href="https://doi.org/10.3389/fsufs.2021.564900">estimates of carbon sequestration for various climates and soil types</a> based on averages over large areas. We believe that regulators need <a href="https://doi.org/10.5194/bg-18-3147-2021">rigorous models</a> verified by measurements to avoid crediting carbon that never ends up in soil or doesn’t remain there for long. </p>
<p>But verification isn’t easy. Scientists are still searching for <a href="https://doi.org/10.1111/gcb.14815">quick, accurate, cost-effective ways</a> to sample and analyze soils. </p>
<p>Possible approaches include <a href="https://doi.org/10.3389/fenvs.2021.634472">infrared spectroscopy</a> – which identifies materials in soil by analyzing how they absorb or reflect infrared light – or <a href="https://doi.org/10.1038/s41561-021-00744-x">machine learning</a>, which can find patterns in large data sets quickly. Studies conducted in the <a href="https://link.springer.com/article/10.1007%2Fs10533-021-00755-1">U.S. Great Plains</a>, <a href="https://doi.org/10.3389/fenvs.2021.634472">the United Kingdom and the European Union</a> suggest these are promising, low-cost methods. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/408483/original/file-20210626-14-im52kz.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Graphic showing roadblocks to soil carbon market integration." src="https://images.theconversation.com/files/408483/original/file-20210626-14-im52kz.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/408483/original/file-20210626-14-im52kz.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=419&fit=crop&dpr=1 600w, https://images.theconversation.com/files/408483/original/file-20210626-14-im52kz.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=419&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/408483/original/file-20210626-14-im52kz.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=419&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/408483/original/file-20210626-14-im52kz.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=526&fit=crop&dpr=1 754w, https://images.theconversation.com/files/408483/original/file-20210626-14-im52kz.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=526&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/408483/original/file-20210626-14-im52kz.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=526&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Integrating carbon into markets poses scientific, economic and technical challenges.</span>
<span class="attribution"><a class="source" href="https://www.research.colostate.edu/cip/scsc/">CSU Soil Carbon Solutions Center</a>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<p>Another priority is developing national minimum standards to predict and properly value soil carbon capture. Carbon may reside in soil anywhere from days to millennia, so time scale is an important consideration for markets. In our view, credits should reflect the duration carbon resides in soil, with full offsets generated only for <a href="https://theconversation.com/soil-carbon-is-a-valuable-resource-but-all-soil-carbon-is-not-created-equal-129175">longer-lasting storage</a>.</p>
<p>We also believe that these programs must consider an operation’s net greenhouse gas emissions. For example, practices may store more carbon in soil but also increase emissions of <a href="https://doi.org/10.1111/gcb.15342">nitrous oxide, another greenhouse gas</a>. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/408530/original/file-20210627-24-1gkfh46.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Well-designed soil carbon policies will benefit farmers and society." src="https://images.theconversation.com/files/408530/original/file-20210627-24-1gkfh46.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/408530/original/file-20210627-24-1gkfh46.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=522&fit=crop&dpr=1 600w, https://images.theconversation.com/files/408530/original/file-20210627-24-1gkfh46.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=522&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/408530/original/file-20210627-24-1gkfh46.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=522&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/408530/original/file-20210627-24-1gkfh46.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=656&fit=crop&dpr=1 754w, https://images.theconversation.com/files/408530/original/file-20210627-24-1gkfh46.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=656&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/408530/original/file-20210627-24-1gkfh46.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=656&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Backed by effective technologies and policies, carbon farming can improve ecosystems and help to slow climate change.</span>
<span class="attribution"><a class="source" href="https://www.research.colostate.edu/cip/scsc/">CSU Soil Carbon Solutions Center</a>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<h2>Benefits and challenges</h2>
<p>Rebuilding carbon-rich soil supports farmers’ bottom lines by improving soil health and <a href="https://doi.org/10.5194/soil-5-15-2019">increasing crop yields</a>. But federal incentives could preferentially provide resources to <a href="https://www.ers.usda.gov/amber-waves/2017/december/us-cropland-is-consolidating-into-larger-farms/">big operations</a> that have greater ability to sequester carbon on their vast acreage. </p>
<p>That’s been the case with U.S. farm subsidies: Over the past 25 years, <a href="https://farm.ewg.org/progdetail.php?fips=00000&progcode=totalfarm&page=conc&regionname=theUnitedStates">10% of the largest farms received 78% of subsidies</a>. </p>
<p>Since these practices benefit farmers, some may use them even without policy incentives. As we see it, <a href="https://www.offsetguide.org/high-quality-offsets/additionality">to avoid paying for soil carbon increases that would have occurred anyway</a>, carbon banks should avoid crediting farms for adopting practices known to be profitable in their regions. </p>
<p>Ultimately, the goals of climate policy include curbing greenhouse gas emissions and actively removing carbon dioxide from the atmosphere. Before farmers receive soil carbon credits they can sell to offset other sources of emissions, we believe their value must be accurately assessed to ensure that society gets what it pays for.</p>
<p><em>Editor’s note: This article has been updated to reflect that IndigoAg does not purchase carbon credits.</em></p>
<p>[<em>Get the best of The Conversation, every weekend.</em> <a href="https://theconversation.com/us/newsletters/weekly-highlights-61?utm_source=TCUS&utm_medium=inline-link&utm_campaign=newsletter-text&utm_content=weeklybest">Sign up for our weekly newsletter</a>.]</p><img src="https://counter.theconversation.com/content/160243/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Laura van der Pol receives funding from the United Stated Department of Agriculture National Institute of Food and Agriculture as well as the National Science Foundation Graduate Research Fellowship Program.</span></em></p><p class="fine-print"><em><span>Dale Manning receives funding from USDA.</span></em></p><p class="fine-print"><em><span>Francesca Cotrufo receives funding from
NSF, USDA, DOE, Shell, MacDonald, GeneralMills
She is a founding member of Cquester Analytics LLC</span></em></p><p class="fine-print"><em><span>Megan Machmuller receives funding from WSARE, CDA, USDA. She is a founding member of Cquester Analytics LLC.</span></em></p>Policymakers want to pay farmers for storing carbon in soil, but there are no uniform rules yet for measuring, reporting or verifying the results. Four scholars offer some ground rules.Laura van der Pol, Ph.D Student in Ecology, Colorado State UniversityDale Manning, Associate Professor of Agricultural and Resource Economics, Colorado State UniversityFrancesca Cotrufo, Professor, Department of Soil and Crop Sciences, Colorado State UniversityMegan Machmuller, Research Scientist, Colorado State UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1613582021-06-24T20:12:17Z2021-06-24T20:12:17ZUS scheme used by Australian farmers reveals the dangers of trading soil carbon to tackle climate change<figure><img src="https://images.theconversation.com/files/407840/original/file-20210623-27-13co042.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C5607%2C3732&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">Shutterstock</span></span></figcaption></figure><p>Soil carbon is in the spotlight in Australia. A key plank in the Morrison government’s <a href="https://www.industry.gov.au/sites/default/files/September%202020/document/first-low-emissions-technology-statement-2020.pdf">technology-led</a> emissions reduction policy, it involves changing farming techniques so soils store more carbon from the atmosphere.</p>
<p>Farmers can encourage and accelerate this process through methods that increase plant production, such as improving nutrient management or sowing permanent pastures. For each unit of atmospheric carbon they remove in this way, farmers can earn “carbon credits” to be sold in emissions trading markets.</p>
<p>But not all carbon credits are created equal. In one high-profile <a href="https://www.beefcentral.com/news/aus-cattle-company-makes-global-carbon-credit-sale-to-microsoft/">deal</a> in January, an Australian farm sold soil carbon credits to Microsoft under a scheme based in the United States. We analysed the methodology behind the trade, and found some increases in soil carbon claimed under the scheme were far too optimistic. </p>
<p>It’s just one of several problems raised by the sale of carbon credits offshore. If not addressed, the credibility of carbon trading will be undermined. Ultimately the climate - and the planet - will be the loser.</p>
<figure class="align-center ">
<img alt="sunset on farm with cattle and trees" src="https://images.theconversation.com/files/407842/original/file-20210623-21-k64xg8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/407842/original/file-20210623-21-k64xg8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/407842/original/file-20210623-21-k64xg8.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/407842/original/file-20210623-21-k64xg8.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/407842/original/file-20210623-21-k64xg8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/407842/original/file-20210623-21-k64xg8.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/407842/original/file-20210623-21-k64xg8.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">The integrity of soil carbon trading must be assured.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<h2>What is soil carbon trading?</h2>
<p>Plants naturally remove carbon dioxide (CO₂) from the air through photosynthesis. As plants decompose, carbon-laden organic matter is added to the soil. If more organic matter is added than is lost, soil carbon levels increase. </p>
<p>Carbon trading schemes require the increase in soil carbon levels to be measured. The measurement methods are well-established, but can be costly and complex because they involve collecting and analysing large numbers of soil samples. And different carbon credit schemes measure the change in different ways - some more robust than others.</p>
<p>The Australian government’s Emissions Reduction Fund has a rigorous approach to soil sampling, laboratory analysis and calculation of credits. This ensures only genuine removals of atmospheric carbon are rewarded, in the <a href="http://www.cleanenergyregulator.gov.au/OSR/ANREU/types-of-emissions-units/australian-carbon-credit-units">form of</a> “Australian Carbon Credit Units”.</p>
<p>Farmers can choose other schemes under which to earn carbon credits, such as the US-based carbon offset <a href="https://www.regen.network/">platform</a> Regen Network.</p>
<p>Regen Network’s method for estimating soil carbon largely involves collecting data via satellite imagery. The extent of physical on-the-ground soil sampling is limited. </p>
<p>Regen Network issues “CarbonPlus credits” to farmers deemed to have increased soil carbon stores. Farmers then sell these credits on the Regen Network trading platform.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/nJ3IFYuYlcY?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Regen Network video explaining its remote sensing methods.</span></figcaption>
</figure>
<h2>‘A number of concerns’</h2>
<p>It was Regen Network which sold Microsoft the soil carbon credits generated by an Australian farm, Wilmot Station. Wilmot is owned by the Macdoch Group, and other Macdoch properties have also claimed carbon credits under the Regen Scheme. </p>
<p>Regen Network should be applauded for making its methods and calculations available online. And we appreciate Regen’s open, collaborative approach to developing its methods. </p>
<p>However, we have reviewed their documents and have a number of concerns:</p>
<ul>
<li><p>the dry weight of soil in a known volume, also known as “bulk density”, is a key factor in calculating soil carbon stocks. Rather than bulk density being measured from field samples, it was calculated using an equation. We examined this method and determined it was far less reliable than field sampling</p></li>
<li><p>Estimates of soil carbon were not adjusted for gravel content. Because gravel contains no carbon, carbon stock may have been overestimated</p></li>
<li><p>The remote sensing used by Regen Network involved assessment of vegetation cover via satellite imagery, from which soil carbon levels were estimated. However, vegetation cover obscures soil, and research has found predictions of soil carbon using this method are highly <a href="https://www.mdpi.com/2072-4292/11/14/1683/htm">uncertain</a>.</p></li>
</ul>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/the-morrison-government-wants-to-suck-co-out-of-the-atmosphere-here-are-7-ways-to-do-it-144941">The Morrison government wants to suck CO₂ out of the atmosphere. Here are 7 ways to do it</a>
</strong>
</em>
</p>
<hr>
<p>Wilmot increased soil carbon, or “sequestration”, through changes to grazing and pasture management. The resulting rates of carbon storage calculated by Regen Network were extremely high – 7,660 tonnes of carbon over 1,094 hectares. This amounts to 7 tonnes of carbon per hectare from <a href="https://regen-registry.s3.amazonaws.com/projects/wilmot/Wilmot+Monitoring+Report+2019.pdf">2018 to 2019</a>. </p>
<p>These results are not consistent with our experience of what is possible through pasture management. For example, the CSIRO has <a href="https://publications.csiro.au/publications/publication/PIcsiro:EP10121">documented</a> soil carbon increases of 0.1 to 0.3 tonnes of carbon per hectare per year in Australia from a range of methods to increase pasture production.</p>
<p>We believe inaccurate methods have led to the carbon increase being overestimated. Thus, it appears excess carbon credits may have been awarded. </p>
<p>Many carbon trading schemes apply <a href="https://www.offsetguide.org/high-quality-offsets/">rules</a> to ensure integrity is maintained. These include:</p>
<ul>
<li><p>an “additionality test” to ensure the extra carbon storage in the soil would not have happened anyway. It would prevent, for example, farmers claiming credits for practices they adopted in the past</p></li>
<li><p>ensuring sequestered carbon is maintained over time</p></li>
<li><p>disallowing double-counting of credits – for example, by preventing a country claiming credits that have been sold offshore.</p></li>
</ul>
<p>The Emissions Reduction Fund and other well-recognised international schemes, such as <a href="https://verra.org/project/vcs-program/">Verra</a> and <a href="https://www.goldstandard.org/">Gold Standard</a>, apply these rules stringently. Regen Network’s safeguards are less rigorous.</p>
<p>Responses to these claims from Regen Network and Macdoch Group can be found at the end of this article. A full response from Regen can also be found <a href="https://docs.google.com/document/d/1neVVUoyoUsyD_UQM-xBzQ-cAvf3DxqNmHhrZxMmWzSg/edit">here</a>.</p>
<figure class="align-center ">
<img alt="diagram. showing arms, money, laptop and leaves over world map" src="https://images.theconversation.com/files/407841/original/file-20210623-13-97dzfp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/407841/original/file-20210623-13-97dzfp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=257&fit=crop&dpr=1 600w, https://images.theconversation.com/files/407841/original/file-20210623-13-97dzfp.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=257&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/407841/original/file-20210623-13-97dzfp.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=257&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/407841/original/file-20210623-13-97dzfp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=323&fit=crop&dpr=1 754w, https://images.theconversation.com/files/407841/original/file-20210623-13-97dzfp.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=323&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/407841/original/file-20210623-13-97dzfp.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=323&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Carbon trading is a way for farmers to make money by changing their land management practices.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<h2>Not in the national interest?</h2>
<p>Putting aside the problems noted above, the offshore sale of soil carbon credits generated by Australian farmers raises other concerns.</p>
<p>First, selling credits offshore means Australia loses out, by not being able to claim the abatement towards our own <a href="https://www.environment.nsw.gov.au/topics/climate-change/net-zero-plan">government</a> and <a href="https://www.mla.com.au/research-and-development/Environment-sustainability/carbon-neutral-2030-rd/cn30/">industry</a> targets.</p>
<p>Second, soil carbon does not have unlimited emissions reduction potential. The quantum of carbon that can be stored in each hectare of soil is <a href="https://onlinelibrary.wiley.com/doi/10.1111/ejss.12194">constrained</a>, and limited by factors such as land availability and <a href="https://www.sciencedirect.com/science/article/abs/pii/S0016706118301216">climate change</a>. So measures to increase soil carbon should not detract from society’s efforts to reduce emissions from fossil fuel use.</p>
<p>And third, ensuring carbon remains in soil long after it’s deposited is a <a href="https://pubmed.ncbi.nlm.nih.gov/32148267/">challenge</a> because soil microbes break down organic matter. Carbon credit schemes commonly manage this by requiring a “buffer” of unsold credits. If stored carbon is lost, farmers must relinquish credits from the buffer. </p>
<p>If the loss is greater than the buffer, credits must be purchased to make up the difference. This exposes farmers to financial risk, especially if <a href="https://www.greenbiz.com/article/carbon-offset-prices-set-increase-tenfold-2030">carbon prices rise</a>.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/we-need-more-carbon-in-our-soil-to-help-australian-farmers-through-the-drought-102991">We need more carbon in our soil to help Australian farmers through the drought</a>
</strong>
</em>
</p>
<hr>
<figure class="align-center ">
<img alt="farmer sits on rock" src="https://images.theconversation.com/files/407843/original/file-20210623-13-jvp69u.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/407843/original/file-20210623-13-jvp69u.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/407843/original/file-20210623-13-jvp69u.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/407843/original/file-20210623-13-jvp69u.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/407843/original/file-20210623-13-jvp69u.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/407843/original/file-20210623-13-jvp69u.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/407843/original/file-20210623-13-jvp69u.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">Poorly managed carbon trading schemes can put farmers at financial risk.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<h2>Getting it right</h2>
<p>Soil carbon is a promising way for Australia to substantially reduce its emissions. But methods used to measure gains in soil carbon must be accurate. </p>
<p>Carbon markets must be regulated to ensure credit is awarded for genuine abatement, and risks to farmers are limited. And the extent to which offshore carbon markets prevent Australia from meeting its own obligations to reduce emissions should be clarified and managed.</p>
<p>Improving the integrity of soil carbon trading will have benefits beyond emissions reduction. It will also improve soil health and farm productivity, helping agriculture become more resilient under climate change.</p>
<hr>
<h2>Regen Network response</h2>
<p>Regen Network provided The Conversation with a response to concerns raised in this article. The full nine-page statement provided by Regen Network is available <a href="https://docs.google.com/document/d/1neVVUoyoUsyD_UQM-xBzQ-cAvf3DxqNmHhrZxMmWzSg/edit">here</a>.</p>
<p>The following is a brief summary of Regen Network’s statement:</p>
<p><strong>- Limited on-ground soil sampling</strong>: Regen Network said its usual minimum number of soil samples was not reached in the case of Wilmot Station, because historical soil samples - taken before the project began - were used. To compensate for this, relevant sample data from a different farm was combined with data from Wilmot.</p>
<p>“We understand the use of ancillary data does not follow best practice and our team is working hard to ensure future projects are run using a sufficient number of samples,” Regen Network said.</p>
<p><strong>- Bulk density:</strong> Regen Network said the historical sample data from Wilmot did not include “bulk density” measurements needed to estimate carbon stocks, which required “deviations” from its usual methodology. However the company was taking steps to ensure such estimates in future projects “can be provided with higher degrees of accuracy”.</p>
<p><strong>- Gravel content:</strong> Regen Network said lab reports for soil samples included only the weight, not volume, of gravel present. “Best sampling practice should include the gravel volume as an essential parameter for accurate bulk density measurements. We will make sure to address this in our next round of upgrades and appreciate the observation!” the statement said.</p>
<p><strong>- Remote sensing of vegetation:</strong> Regen Network said it did not use vegetation assessment at Wilmot station. It tested a vegetation assessment index at another property and found it ineffective at estimating soil carbon. At Wilmot station Regen used so-called individual “spectral bands” to estimate soil carbon at locations where on-ground sampling was not undertaken.</p>
<p><strong>- Sequestration rates at Wilmot:</strong> Regen Network said while it was difficult to directly compare local sequestration rates across climatic and geologic zones, the sequestration rates for the projects in question “fall within the relatively wide range of sequestration rates” reported in key scientific studies.</p>
<p>Regen Network said its methodology “provides a conservative estimate on the final number of credits issued”. Its statement outlines the steps taken to ensure soil carbon levels are not overestimated.</p>
<p><strong>- Integrity safeguards:</strong> Regen Network said it employs standards “based both on existing standards of reputable programs […] and inputs from project developers, in order to come up with a standard that not only is rigorous but also practical”. Regen Network takes steps to ensure additionality and permanence of carbon stores, as well as avoid double counting of carbon credits generated through their platform.</p>
<p>A more detailed response from Regen Network can be found <a href="https://docs.google.com/document/d/1neVVUoyoUsyD_UQM-xBzQ-cAvf3DxqNmHhrZxMmWzSg/edit">here</a>.</p>
<hr>
<h2>Wilmot Station response</h2>
<p>Wilmot Station provided the following response from Alasdair Macleod, chairman of Macdoch Group. It has been edited for brevity:</p>
<p><em>We entered into the deals with Regen Network/Microsoft because we wanted to give a hint of the huge potential that we believe exists for farmers in Australia and globally to sequester soil carbon which can be sold through offset markets or via other methods of value creation.</em></p>
<p><em>Whilst we recognise that the soil carbon credits generated on the Macdoch Group properties in the Regen Network/Microsoft deal will not be included in Australia’s national carbon accounts, it is our hope that over time the regulated market will move towards including appropriately rigorous transactions such as these in some form.</em></p>
<p><em>At the same time we have also been working closely with the Australian government, industry organisations, academia and other interested parties on Macdoch Group properties to develop appropriate soil carbon methodologies under the government’s Climate Solutions Fund.</em></p>
<p><em>This is because carbon measurement methodologies are an evolving science. We have always acknowledged and will welcome improvements that will be made over the coming years to the methodologies utilised by both the voluntary and regulated markets.</em></p>
<p><em>In any event it has become clear that there is huge demand from the private sector for offset deals of this nature and we will continue to work towards ensuring that other farmers can take advantage of the opportunities that will become available to those that are farming in a carbon-friendly fashion.</em></p><img src="https://counter.theconversation.com/content/161358/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Aaron Simmons is a Technical Specialist in Climate Change Mitigation with the NSW Department of Primary Industries and an Adjunct Senior Research Fellow with The University of New England. Aaron has received funding from Australian Wool Innovation, Grains Research and Development Corporation, Cotton Research and Development Corporation, Dairy Australia and the Commonwealth government. </span></em></p><p class="fine-print"><em><span>Annette Cowie is a Senior Principal Research Scientist in the Climate Branch at the NSW Department of Primary Industries, and Adjunct Professor in the School of Environmental and Rural Science at the University of New England. She has received funding for soil carbon research from NSW and Commonwealth government programs. Annette is a member of Soil Science Australia, a not-for-profit, professional association for soil scientists and people interested in the responsible management of Australia’s soil resources.</span></em></p><p class="fine-print"><em><span>Brian Wilson is a member of academic staff and researcher at the University of New England and a Principal Research Scientist with NSW State Government. He has received research income from a range of State and Commonwealth organisations to engage in research relating to soil carbon.</span></em></p><p class="fine-print"><em><span>Mark Farrell has received funding for soil carbon research from Commonwealth, State and industry programmes. He is a member of Soil Science Australia, a not-for-profit, professional association for soil scientists and people interested in the responsible management of Australia's soil resources.</span></em></p><p class="fine-print"><em><span>Matthew Tom Harrison is an Associate Professor and Systems Modelling Team Leader at the University of Tasmania. He receives funding from the Commonwealth and Tasmanian Government, as well as Meat & Livestock Australia. His research examines pathways for improving the sustainability of agricultural systems, including avenues for greenhouse gas emissions mitigation through soil carbon sequestration.</span></em></p><p class="fine-print"><em><span>Peter Grace has received funding from federal government sources and Rural Development Corporations with respect to sustainable agricultural systems and reducing greenhouse gas emissions. </span></em></p><p class="fine-print"><em><span>Richard Eckard receives funding from Commonwealth Government, as well as Meat & Livestock Australia and Dairy Australia. </span></em></p><p class="fine-print"><em><span>Vanessa Wong receives funding from the Victorian State Government and the Australian Research Council. She is currently the President of Soil Science Australia, a not-for-profit, professional association for soil scientists and people interested in the responsible management of Australia’s soil resources </span></em></p><p class="fine-print"><em><span>Warwick Badgery is a Research Leader in Rangelands and Pasture with the NSW Department of Primary Industries and has honorary positions with Melbourne University and China Agricultural University. He receives funding from the Federal Government, Meat and Livestock Australia and the food Agility CRC for agricultural systems and soil carbon research. </span></em></p>If problems in such schemes are not addressed, the credibility of soil carbon trading will be undermined. Ultimately the climate - and the planet - will be the loser.Aaron Simmons, Adjunct Senior Research Fellow, University of New EnglandAnnette Cowie, Adjunct Professor, University of New EnglandBrian Wilson, Associate Professor, University of New EnglandMark Farrell, Principal Research Scientist, CSIROMatthew Tom Harrison, Associate Professor of Sustainable Agriculture, University of TasmaniaPeter Grace, Professor of Global Change, Queensland University of TechnologyRichard Eckard, Professor & Director, Primary Industries Climate Challenges Centre, The University of MelbourneVanessa Wong, Associate Professor, Monash UniversityWarwick Badgery, Research Leader Pastures an Rangelands, The University of MelbourneLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1607042021-05-12T08:20:44Z2021-05-12T08:20:44ZPay dirt: $200 million plan for Australia’s degraded soil is a crucial turning point<figure><img src="https://images.theconversation.com/files/400212/original/file-20210512-18-61b5qy.jpg?ixlib=rb-1.1.0&rect=28%2C0%2C4665%2C3103&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">Shutterstock</span></span></figcaption></figure><p>The food we eat, the clothes we wear, the air we breathe, the water we drink – it’s all underpinned by healthy and productive soils. Since Europeans arrived in Australia, the continent’s soil has steadily been degraded. Yet, until now, we’ve lacked an integrated national approach to managing this valuable and finite resource.</p>
<p>That changed in last night’s federal budget, when Treasurer Josh Frydenberg announced almost A$200 million for a <a href="https://www.awe.gov.au/sites/default/files/2021-05/national-soil-strategy-factsheet.pdf">National Soils Strategy</a>. The 20-year plan recognises the vital role of soils for environmental and human health, the economy, food security, biodiversity and climate resilience.</p>
<p>Our soils face a range of threats, including the loss of prime agricultural land, erosion, acidification, salt accumulation, contamination and carbon loss. Climate change also puts pressure on our soils through through droughts, storms, bushfires and floods.</p>
<p>We contributed expertise as the soil policy was being developed, and believe the final strategy represents a long-needed turning point for this crucial natural asset.</p>
<figure class="align-center ">
<img alt="farm in dust storm" src="https://images.theconversation.com/files/400214/original/file-20210512-17-1vmsho7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/400214/original/file-20210512-17-1vmsho7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=370&fit=crop&dpr=1 600w, https://images.theconversation.com/files/400214/original/file-20210512-17-1vmsho7.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=370&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/400214/original/file-20210512-17-1vmsho7.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=370&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/400214/original/file-20210512-17-1vmsho7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=465&fit=crop&dpr=1 754w, https://images.theconversation.com/files/400214/original/file-20210512-17-1vmsho7.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=465&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/400214/original/file-20210512-17-1vmsho7.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=465&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Australia’s soils have been degrading since European settlement.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<h2>Why soil matters</h2>
<p>Soil contains organic matter, minerals, gases, water and living organisms. It is slow to form – the average rate of soil production globally is <a href="https://www.sciencedirect.com/science/article/pii/S0016706113003601">around 114 millimetres per 1,000 years</a> – and is considered a non-renewable resource.</p>
<p>Soil underpins a myriad of economic activities. In Australia, it <a href="https://www.soilscienceaustralia.org.au/about/save-our-soils/sos-value-of-australias-soils/2">directly contributes about</a> A$63 billion each year to the economy through agriculture production alone.</p>
<p>Healthy soil is necessary for:</p>
<ul>
<li><p>food and fibre production </p></li>
<li><p>filtering water and retaining sediment to ensure healthy landscapes</p></li>
<li><p>maintaining air quality by preventing dust storms</p></li>
<li><p>carbon storage to help mitigate climate change</p></li>
<li><p>environmental functions such as plant growth </p></li>
<li><p>human nutrition (soil provides nutrients to plants and animals which are transferred to humans once consumed)</p></li>
<li><p>many drugs and vaccines upon which humans rely, such as penicillin</p></li>
<li><p>safe infrastructure (acid sulfate soils and salinity can damage structures such as housing, bridges and roads)</p></li>
<li><p>resilience to natural disasters such as storms, bushfires, floods and droughts. </p></li>
</ul>
<p>However, land degradation, climate change and poor management practices threaten our soil resources.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/even-after-the-rains-australias-environment-scores-a-3-out-of-10-these-regions-are-struggling-the-most-157590">Even after the rains, Australia's environment scores a 3 out of 10. These regions are struggling the most</a>
</strong>
</em>
</p>
<hr>
<figure class="align-center ">
<img alt="An overly saline mustard field" src="https://images.theconversation.com/files/400217/original/file-20210512-19-1mtlki0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/400217/original/file-20210512-19-1mtlki0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/400217/original/file-20210512-19-1mtlki0.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/400217/original/file-20210512-19-1mtlki0.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/400217/original/file-20210512-19-1mtlki0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/400217/original/file-20210512-19-1mtlki0.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/400217/original/file-20210512-19-1mtlki0.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">Soil salinity can ruin crops.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<h2>What lies beneath?</h2>
<p>Until now, Australia has lacked a nationally consistent approach to monitor soil health, nor a readily accessible means of storing that data. That means at a national level, our understanding of soil condition, and how it’s changed, has been limited.</p>
<p>Soil monitoring has largely been conducted through various regional, state and federal programs. These often operate in isolation and have differing aims and objectives. And overall investment has not been large or quick enough to create broad improvements in soil health.</p>
<p>In comparison, well-established standardised national systems exist to monitor <a href="https://www.tern.org.au/">terrestrial ecosystems</a>, <a href="http://www.bom.gov.au/?ref=logo">weather, climate and water</a>. These allow an assessment of longer trends and changes to baseline conditions.</p>
<p>The need for a national soil assessment was recognised as far back <a href="https://theconversation.com/search/result?sg=3cba8a33-10bb-4731-b739-16817b5937c1&sp=1&sr=4&url=%2Fa-more-sustainable-australia-we-need-to-talk-about-our-soils-16555">as 2008</a>. And there have long been <a href="https://publications.csiro.au/rpr/download?pid=procite:6de96f40-58f0-4ddf-88de-fe874629fa1d&dsid=DS1">calls for</a> long-term monitoring, consistent information and baseline data collection. </p>
<figure class="align-center ">
<img alt="hand holding dirt" src="https://images.theconversation.com/files/400218/original/file-20210512-16-1871aho.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/400218/original/file-20210512-16-1871aho.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/400218/original/file-20210512-16-1871aho.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/400218/original/file-20210512-16-1871aho.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/400218/original/file-20210512-16-1871aho.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/400218/original/file-20210512-16-1871aho.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/400218/original/file-20210512-16-1871aho.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">The funding will help farmers monitor the health of their soil.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<h2>Change from the ground up</h2>
<p>Importantly, the strategy takes a long term view of sustainable soil management. It also considers soil beyond its traditional role in agricultural production and explicitly identifies criteria to measure progress.</p>
<p>The strategy has three arms:</p>
<p><strong>1. Prioritise soil health</strong></p>
<p>This goal takes a “soils first” approach in that sustainable soil management is the primary consideration in policy development and management strategies. This recognises how environmental and agricultural problems can start with poor soil management and create further challenges. For example, soil acidification can lead to <a href="https://publications.csiro.au/rpr/download?pid=csiro:EP177962&dsid=DS3">declines in terrestrial biodiversity</a>, and soil constraints must be addressed first to arrest this. </p>
<p><strong>2. Empower soil stewards and innovation</strong></p>
<p>This approach gives incentives to farmers and other land managers, such as rebates for sampling to determine the soil carbon levels. Carbon is an important measure of soil condition. Gathering such information will help land managers arrest the decline in soil condition, enhancing productivity and soil health.</p>
<p><strong>3. Secure soil science</strong></p>
<p>This approach aims to increase soil knowledge through standardised data collection, management and storage. It will allow for more informed decisions using reliable, up-to-date, accessible information. </p>
<p>Part of this aim involves strengthening training and accreditation programs, and integrating soils into the national school curriculum. This will help create a new generation of soil experts to replace the current crop which is trending to retirement.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/we-need-more-carbon-in-our-soil-to-help-australian-farmers-through-the-drought-102991">We need more carbon in our soil to help Australian farmers through the drought</a>
</strong>
</em>
</p>
<hr>
<figure class="align-center ">
<img alt="young woman conducting soil testing" src="https://images.theconversation.com/files/400219/original/file-20210512-15-152kp70.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/400219/original/file-20210512-15-152kp70.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/400219/original/file-20210512-15-152kp70.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/400219/original/file-20210512-15-152kp70.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/400219/original/file-20210512-15-152kp70.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/400219/original/file-20210512-15-152kp70.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/400219/original/file-20210512-15-152kp70.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">The strategy aims to train a new generation of soil experts.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<h2>On solid ground</h2>
<p>Overall, the National Soils Strategy aims to deliver coordinated on-ground action and improve research, education and monitoring. The strategy broadly aligns with the needs of those who had input into its development, including governments, industry, academia, Landcare groups and non-government organisations. </p>
<p>However, while the importance of Indigenous land management practices is clearly acknowledged, the integration and incorporation of these practices should be more clearly defined. </p>
<p>The monitoring program encourages farmers to test their soil and incorporate the de-identified results in to the national database. Care should be taken to ensure <a href="https://ebooks.publish.csiro.au/content/soil-analysis-interpretation-manual">sampling is done appropriately</a> for the data to be useful. </p>
<p>The time frame for the initial phase of the strategy is short – pilot programs need to be delivered between two and four years. This will be challenging to deliver.</p>
<p>Separate to the strategy, the budget allocated A$59.6 million to soil carbon initiatives. There is <a href="https://www.pmc.gov.au/news-centre/domestic-policy/digging-deep-soil-organic-carbon-earth-day">increasing recognition</a> of how improved land use and management can help boost soil carbon stores, which is key to tackling climate change. But storing carbon permanently in soils comes with a number of <a href="https://theconversation.com/dishing-the-dirt-australias-move-to-store-carbon-in-soil-is-a-problem-for-tackling-climate-change-141656">challenges</a>. This funding may be appropriate only if directed to address those areas where knowledge gaps exist. </p>
<p>But overall, the strategy fills a vital gap – providing a national vision and shared goals for managing precious soils across Australia.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/the-morrison-government-wants-to-suck-co-out-of-the-atmosphere-here-are-7-ways-to-do-it-144941">The Morrison government wants to suck CO₂ out of the atmosphere. Here are 7 ways to do it</a>
</strong>
</em>
</p>
<hr>
<img src="https://counter.theconversation.com/content/160704/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Vanessa Wong receives funding from the Victorian State Government and the Australian Research Council. She is currently the President of Soil Science Australia, a not-for-profit, professional association for soil scientists and people interested in the responsible management of Australia’s soil resources.</span></em></p><p class="fine-print"><em><span>Luke Mosley receives funding from the South Australian and Commonwealth Governments for various projects. He is Immediate Past President and is affiliated with Soil Science Australia, a not-for-profit, professional association for soil scientists and people interested in the responsible management of Australia’s soil resources.</span></em></p>Soil underpins Australia’s economy – yet since Europeans arrived, the natural asset has steadily been degraded. A new national plan aims to change that.Vanessa Wong, Associate professor, Monash UniversityLuke Mosley, Associate Professor, University of AdelaideLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1572202021-04-28T12:16:28Z2021-04-28T12:16:28ZClimate-friendly farming strategies can improve the land and generate income for farmers<figure><img src="https://images.theconversation.com/files/397449/original/file-20210428-21-1py5npc.jpg?ixlib=rb-1.1.0&rect=34%2C8%2C5635%2C3723&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">A prairie strip filled with flowers and wild rye grass between soybean fields on Tim Smith's farm near Eagle Grove, Iowa, reduces greenhouse gases and stores carbon in the soil.</span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/news-photo/prairie-strip-filled-with-black-eyed-susan-flowers-in-news-photo/629903308">The Washington Post via Getty Images</a></span></figcaption></figure><p>Agriculture has not been a central part of U.S. climate policy in the past, even though climate change is <a href="https://nca2018.globalchange.gov/chapter/10/">altering weather patterns that farmers rely on</a>. Now, however, President Biden has directed the U.S. Department of Agriculture (USDA) to develop a <a href="https://www.whitehouse.gov/briefing-room/statements-releases/2021/01/27/fact-sheet-president-biden-takes-executive-actions-to-tackle-the-climate-crisis-at-home-and-abroad-create-jobs-and-restore-scientific-integrity-across-federal-government/">climate-smart agriculture and forestry strategy</a>.</p>
<p>As a scientist <a href="https://scholar.google.com/citations?user=-6bpfYUAAAAJ&hl=en">focusing on agricultural land use</a> and adviser to several farm organizations, I have the privilege of working alongside farmers who have figured out how to do just that. I am enthusiastic about farmer-led solutions to climate change. What does this look like?</p>
<p><div data-react-class="Tweet" data-react-props="{"tweetId":"1385273269599752196"}"></div></p>
<h2>Restore strips of native plants around farm fields</h2>
<p>Plants remove carbon from the atmosphere as they grow, and soil can soak up carbon and store it. These abilities are key to climate solutions that crop farmers can readily deploy today.</p>
<p>Seeding narrow strips of land within and around crop fields with native plants is an effective and affordable way to make farming more climate-friendly. Iowa State University’s <a href="https://www.nrem.iastate.edu/research/STRIPS/">STRIPS Project</a> has shown that this technique reduces erosion and nutrient loss from soil and supports birds and insects.</p>
<p>Prairie strips can reduce emissions of <a href="https://doi.org/10.2136/sssaj2014.05.0221">nitrous oxide</a>, a greenhouse gas <a href="https://www.epa.gov/ghgemissions/overview-greenhouse-gases#nitrous-oxide">298 times more potent</a> than carbon dioxide. Nitrous oxide emissions vary widely across agricultural landscapes and over time, but the largest contributions are associated with <a href="https://doi.org/10.1029/2018JG004629">poorly drained croplands</a>. </p>
<p>Nitrous oxide forms under <a href="https://www.nature.com/scitable/knowledge/library/the-nitrogen-cycle-processes-players-and-human-15644632/">anaerobic conditions</a> – environments without oxygen, such as low-lying wet areas of farm fields, where it is produced by soil microbes. The easiest way to keep it from forming is to avoid fertilizing these areas, which amounts to feeding the microbes.</p>
<p>Prairie strips help reduce nitrous oxide emissions by soaking up nitrogen fertilizer that runs off of adjacent cropland. They also can <a href="https://doi.org/10.1002/saj2.20007">store carbon in soil</a> in two ways: by trapping sediment moving down slopes, and by removing carbon dioxide from the atmosphere through photosynthesis and storing this carbon in plant roots and soil.</p>
<figure>
<iframe src="https://player.vimeo.com/video/291571298" width="500" height="281" frameborder="0" webkitallowfullscreen="" mozallowfullscreen="" allowfullscreen=""></iframe>
<figcaption><span class="caption">‘Prairie strips’ integrate native grasses into row crop fields, bringing many environmental benefits.</span></figcaption>
</figure>
<p>Prairie strips are among the <a href="https://doi.org/10.1007/s00267-013-0106-9">least expensive conservation practices </a> available to farmers. This is especially true if the land they occupy is enrolled in the <a href="https://www.fsa.usda.gov/programs-and-services/conservation-programs/conservation-reserve-program/">Conservation Reserve Program</a>, which pays farmers to take environmentally sensitive land out of production and conserve it for other purposes.</p>
<p>Installing prairie strips has <a href="https://www.fsa.usda.gov/Assets/USDA-FSA-Public/usdafiles/FactSheets/2019/crp_clear_initiative_prairie_strip_practice-fact_sheet.pdf">qualified for Conservation Reserve Program funding</a> since 2019. Colleagues and I estimate that via this route, they cost <a href="https://store.extension.iastate.edu/Product/15222">US$8 yearly per acre of cropland treated</a>. A <a href="https://store.extension.iastate.edu/product/16071">recent survey</a> found that about half of Iowa farmers were willing to install prairie strips if they could access federal funds.</p>
<p>On April 21, 2021, Agriculture Secretary Tom Vilsack announced that the agency will <a href="https://www.fsa.usda.gov/news-room/news-releases/2021/usda-expands-and-renews-conservation-reserve-program-in-effort-to-boost-enrollment-and-address-climate-change">expand Conservation Reserve Program enrollment</a> and offer higher payment rates for participating. The department is also creating a new Climate-Smart Practice Incentive to promote strategies that sequester carbon and reduce greenhouse gas emissions. I hope this measure will promote national awareness of prairie strips, which today are known mainly <a href="https://www.instagram.com/p/CMu4AtbjU8W/">in Iowa and neighboring states</a>. </p>
<p><iframe id="3Qtuh" class="tc-infographic-datawrapper" src="https://datawrapper.dwcdn.net/3Qtuh/1/" height="400px" width="100%" style="border: none" frameborder="0"></iframe></p>
<h2>Turn soggy spots into wetlands</h2>
<p>Since nitrous oxide emissions come mainly from wet zones, letting these areas remain as wetlands is another climate-smart strategy. Soggy areas tend to yield poorly in most years, and farmers rarely recoup their investment in cropping them. However, wetlands can be troublesome to farm around, which is why many farmers try to drain and farm through them. </p>
<p>But healthy wetlands also provide benefits: They <a href="https://doi.org/10.1890/09-0216.1">sequester carbon, store and filter water and provide crucial habitat</a> for mammals, birds, frogs and other organisms. The Agriculture Department’s new Climate-Smart Practice Incentive will support wetland restoration on agricultural lands.</p>
<p>Another USDA initiative, the <a href="https://www.fsa.usda.gov/programs-and-services/conservation-programs/farmable-wetlands/index">Farmable Wetland Program</a>, pays farmers to take previously farmed wetlands and buffer areas out of production for 10 or more years. Enrollment is currently capped at 1 million acres. A climate-smart agricultural policy could expand the program by removing the acreage cap and boosting incentive payments.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/397391/original/file-20210427-23-s7o0cp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Low-lying zone of a farm field before and after conversion to a wetland." src="https://images.theconversation.com/files/397391/original/file-20210427-23-s7o0cp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/397391/original/file-20210427-23-s7o0cp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=270&fit=crop&dpr=1 600w, https://images.theconversation.com/files/397391/original/file-20210427-23-s7o0cp.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=270&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/397391/original/file-20210427-23-s7o0cp.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=270&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/397391/original/file-20210427-23-s7o0cp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=339&fit=crop&dpr=1 754w, https://images.theconversation.com/files/397391/original/file-20210427-23-s7o0cp.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=339&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/397391/original/file-20210427-23-s7o0cp.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=339&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 prairie wetland in Minnesota, formerly part of a crop field (left) and restored to provide habitat for water birds (right).</span>
<span class="attribution"><a class="source" href="https://flic.kr/p/EUaPjP">Shawn Papon/USFWS</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<h2>Promote perennial crops, especially grasses</h2>
<p>All crops are not equal when it comes to mitigating climate change and conserving the environment. Perennials – including various types of grasses, shrubs and trees – <a href="https://doi.org/10.1017/S1742170512000385">provide more ecological benefits </a> than annual crops like corn, wheat and soybeans. But they receive less government support. </p>
<p>Just like annual garden plants, annual crops must be replanted every year. Perennial crops live for multiple seasons, so raising them requires fewer climate-warming inputs, such as fertilizer and fuel to power tractors. These crops develop deep roots that soak up water in soggy spots and help stabilize soil on sloping land. </p>
<p>Many fruits, vegetables and forage crops are perennials. Examples include apples, alfalfa, grapes and asparagus. Researchers are working to develop <a href="https://landinstitute.org/our-work/perennial-crops/">perennial versions</a> of grains, legumes and oilseeds such as sunflowers.</p>
<p>There are many opportunities to <a href="https://doi.org/10.1017/S1742170512000385">expand cultivation of perennial crops</a>. Grasses and <a href="https://www.dupageforest.org/plants-wildlife/plants/forbs">forbs</a> – flowering plants with stems and leaves, such as <a href="https://en.wikipedia.org/wiki/Monarda">bee balm</a> – are less expensive to establish and grow than woody crops like willow, and offer farmers more management flexibility.</p>
<p><div data-react-class="InstagramEmbed" data-react-props="{"url":"https://www.instagram.com/p/CNYWwcvh0X9/?utm_source=ig_web_copy_link","accessToken":"127105130696839|b4b75090c9688d81dfd245afe6052f20"}"></div></p>
<p>I direct a transdisciplinary team called <a href="https://cchange.research.iastate.edu/">C-CHANGE</a>, funded by USDA, that is working with farmers to create and expand market-based value chains for perennial grasses. We are helping farmers plant mixtures of native perennial grasses and forbs to build soil health where it has been eroded and protect environmentally sensitive areas. </p>
<p>The grasses can ultimately be harvested and <a href="https://doi.org/10.1002/bbb.1671">processed in biodigesters</a> – devices that break down organic materials to produce energy – along with manure or food waste. This cycle will yield electricity or biomethane from renewable sources that can displace fossil-based energy sources on or off of farms. It also will produce liquid and solid materials that can be used as organic fertilizers, along with <a href="https://cchange.research.iastate.edu/files/2020/10/CCHANGE_Proposal-Narrative_2020-1.pdf">other valuable products</a>. </p>
<p>Replacing fertilizer made from synthetic nitrogen is important for the climate because making it consumes <a href="https://www.wired.com/2008/05/how-to-make-nit/">enormous quantities of natural gas</a> and <a href="https://doi.org/10.1525/elementa.358">releases methane</a> into the atmosphere. Methane is another powerful greenhouse gas, <a href="https://www.epa.gov/ghgemissions/overview-greenhouse-gases">25 times more potent</a> than carbon dioxide. </p>
<p>Biodigestion is <a href="https://doi.org/10.1016/j.rser.2019.109332">widely used in Europe</a> but underdeveloped in the U.S. We expect that the value chain we’re creating will embed it in a larger cycle that creates a market for protective perennial crops, reduces fossil fuel use and returns carbon to the soil. </p>
<p>The Agriculture Department’s <a href="https://www.rd.usda.gov/programs-services/rural-energy-america-program-renewable-energy-systems-energy-efficiency">Rural Energy for America Program</a> provides grants and loans that can be used to support biodigester construction on farms. Expanding this program, which currently is funded at <a href="https://sustainableagriculture.net/publications/grassrootsguide/renewable-energy/renewable-energy-energy-efficiency/">$50 million yearly through 2022</a>, and making biodigesters a priority, is another climate-friendly opportunity.</p>
<p>When I think of climate-smart agriculture, I picture farmlands with lots of perennial vegetation smartly integrated as prairie strips, wetlands and crops. Federal policies and programs that can make such landscapes a reality are already in place. With concerted efforts and investments, they could be expanded to achieve a pace and scale that will help address climate change.</p>
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<p class="fine-print"><em><span>Lisa Schulte Moore has received funding from the U.S. Department of Agriculture, Bia-Echo Foundation, Foundation for Food and Agriculture Research, Walton Family Foundation, McKnight Foundation, Iowa State University, Leopold Center for Sustainable Agriculture, USDA Forest Service, National Science Foundation, US Fish and Wildlife Service, 11th Hour Project, Bayer Crop Science, The Nature Conservancy, Syngenta, Iowa Soybean Association, Iowa Agriculture Water Alliance, DuPont-Pioneer, Renewable Energy Group, Iowa Department of Natural Resources, Iowa Ornithological Union, and Iowa Native Plant Society. She is on the boards of the Great Lakes Bioenergy Research Center, Practical Farmers of Iowa, Iowa Chapter of The Nature Conservancy, and Iowa Wildlife Federation, and advises Iowa Smart Agriculture.</span></em></p>Farmers can help slow climate change by mixing native grasses into croplands, restoring wetlands and raising perennial crops. These strategies also conserve soil and water and build new markets.Lisa Schulte Moore, Professor of Natural Resource Ecology and Management, Iowa State UniversityLicensed as Creative Commons – attribution, no derivatives.