{"id":16244,"date":"2025-12-04T03:00:48","date_gmt":"2025-12-04T08:00:48","guid":{"rendered":"https:\/\/blogs.edf.org\/growingreturns\/?p=16244"},"modified":"2025-12-15T15:28:02","modified_gmt":"2025-12-15T20:28:02","slug":"soil-carbon-facts","status":"publish","type":"post","link":"https:\/\/blogs.edf.org\/growingreturns\/2025\/12\/04\/soil-carbon-facts\/","title":{"rendered":"Digging deep: Separating soil carbon facts from fiction"},"content":{"rendered":"<p><em><strong>Authors: Alison Eagle, Jocelyn Lavallee, Renske Hijbeek<\/strong><\/em><\/p>\n<p>Soil is one of our best allies in tackling climate change, but it\u2019s also one of the most misunderstood. Myths about what soil can (and can\u2019t) do still shape global debates. That\u2019s why scientists from Environmental Defense Fund and Wageningen University dug into the data to bring clarity. Because sound science is the foundation of sound policy.<\/p>\n<p><strong>Why soil matters.<\/strong><\/p>\n<p>Healthy soils are essential for climate change mitigation and sustainable food production. But while improving soil carbon is part of the solution, it\u2019s not a silver bullet. Real progress requires a whole food-system approach that balances production, consumption, and land use \u2013 while cutting emissions across agriculture and beyond.<\/p>\n<p><!--more--><\/p>\n<p><strong>Five myths about soil carbon \u2013 debunked.<\/strong><\/p>\n<p><em>Myth 1: It isn\u2019t feasible to measure soil carbon change directly for large-scale monitoring, reporting and verification (MRV)<\/em><\/p>\n<p>Fact: Direct soil carbon measurement is still the most reliable way to track changes over time, and it\u2019s becoming increasingly more practical at larger scales.<\/p>\n<p>Collecting soil samples and analysing them in a lab takes time, but <a href=\"https:\/\/environment.yale.edu\/news\/article\/direct-measurements-can-reduce-uncertainty-soil-carbon-credit-markets\">studies show<\/a> it works well at scale. Costs per hectare often drop as projects grow.<\/p>\n<p>These measurements are also vital for improving newer methods like process-based modelling and remote sensing, which rely on ground-truth data for accuracy. To ensure <a href=\"https:\/\/blogs.edf.org\/growingreturns\/2025\/03\/24\/improving-soil-carbon-measurement\/\">reliable results<\/a>, it\u2019s crucial to apply consistent protocols and use the same laboratory throughout the project\u2019s lifetime.<\/p>\n<p><em>Myth 2: Huge climate mitigation potential because there\u2019s so much land. <\/em><\/p>\n<p>Fact: Not all farmland is suitable for soil carbon sequestration practices, and many farmers have already adopted improved practices.<\/p>\n<p>Global estimates often assume that nearly all farmers can switch to practices like cover cropping or reduced tillage on all of their cropland. In reality, many already use conservation tillage or cultivate winter crops, and not all production systems \u2013 like potatoes or other root crops \u2013 are compatible with no-till methods. Suitability varies widely across both Europe and the U.S.<\/p>\n<p>For example,<\/p>\n<ul>\n<li><a href=\"https:\/\/doi.org\/10.1029\/2023EF003866\">EDF research<\/a> in the U.S. found only about one-third of cropland is suitable for cover crops.<\/li>\n<li><a href=\"https:\/\/doi.org\/10.1016\/j.eja.2025.127844\">Wageningen University scientists<\/a> found less than a quarter of arable land in Germany and the Netherlands can support additional cover cropping.<\/li>\n<li>Water availability also limits adoption: In Spain, water scarcity makes the cover cropping practices infeasible in many regions.<\/li>\n<\/ul>\n<p>The takeaway: soil carbon strategies need to be regionally tailored, not one-size-fits-all.<\/p>\n<p><em>Myth 3: Cost is the biggest barrier for farmers to sequester soil carbon<\/em><\/p>\n<p>Fact: Environmental and technical barriers often matter more.<\/p>\n<p>There\u2019s a widespread assumption that if we simply pay farmers enough, soil carbon sequestration will scale up quickly. But research shows the reality is far more complex. Biophysical conditions \u2013 like soil type, rainfall, crop rotations \u2013 often determine whether practices like cover cropping or reduced tillage are even possible. For example,<\/p>\n<ul>\n<li><a href=\"https:\/\/doi.org\/10.1016\/j.eja.2025.127844\">Mediterranean climates<\/a>: Water scarcity is the single biggest barrier to cover crop cultivation. When water is limited, farmers understandably prioritize main cash crops over cover crops \u2013 even if subsidies fully cover the operational costs.<\/li>\n<li>Atlantic and Continental regions: Heavy autumn rainfall can make fields inaccessible and increase the risk of soil damage from machinery, preventing timely cover crop planting.<\/li>\n<li>Reduced tillage \u2013 another carbon-boosting practice &#8211; depends on crop type and seasonal conditions; Farmers growing certain crops may find reduced tillage impractical if this leads to more weeds in their fields, leading to interrupted adoption patterns. These realities mean soil carbon practices can\u2019t always be applied consistently year after year \u2013 policies must allow flexibility instead of penalizing farmers.<\/li>\n<\/ul>\n<p>Financial support matters, but it\u2019s not the silver bullet, Research from the U.S. illustrates this point:<\/p>\n<ul>\n<li><a href=\"https:\/\/www.montana.edu\/econ\/klarson\/Practice_Duration-12.pdf\">About 70% of U.S farmers<\/a> who started growing winter cover crops under multi-year incentive programs continued after payments ended \u2013 showing agronomic benefits experienced after transition support can drive persistence following initial adoption.<\/li>\n<li>However, despite decades of available funding \u2013 the U.S. Department of Agriculture has offered payments for winter cover crops since the 1950s \u2013 as of 2022, <a href=\"https:\/\/www.ers.usda.gov\/data-products\/charts-of-note\/chart-detail?chartId=108950#:~:text=Some%20states%20with%20decreased%20cover%20crop%20use,about%20factors%20affecting%20U.S.%20cover%20crop%20adoption\">only 5% of U.S. cropland<\/a> used cover crops by 2022.<\/li>\n<\/ul>\n<p>The evidence is clear: money alone isn\u2019t enough. Successful soil carbon strategies must account for local agronomic realities and climate variability and combine financial incentives with flexible, science-informed policies that make adoption feasible \u2013 not just affordable.<\/p>\n<p><em>Myth 4: Increasing carbon in soil results in higher crop yield and improved soil quality<\/em><\/p>\n<p>Fact: More soil carbon can boost soil health, but yield benefits depend on local conditions.<\/p>\n<p>Adding organic matter, which can increase soil carbon, can improve water retention, soil structure, and nutrients. But these benefits don\u2019t always mean higher yields. Compacted soils may not respond, and certain crops &#8211; such as root and tuber varieties &#8211; gain more than cereals, which already have deeper root systems.<\/p>\n<p><a href=\"https:\/\/link.springer.com\/article\/10.1007\/s11104-016-3031-x\">A Europe-wide study<\/a> of long-term experiments found that soils under stress (very sandy or very wet) see the most improvement when organic matter is added \u2013 but those same soils have lower carbon storage potential, creating <a href=\"https:\/\/onlinelibrary.wiley.com\/doi\/10.1111\/gcb.16570\">trade-offs<\/a> between productivity and climate change mitigation potential.<\/p>\n<p>Effective carbon farming policies should account for these trade-offs to avoid unintended impacts on food security and land use.<\/p>\n<p><em>Myth 5: Soil carbon sequestration can offset fossil fuel and other on-farm emissions (example: enteric methane)<\/em><\/p>\n<p>Fact: Soil carbon can help, but it can\u2019t cancel out emissions from livestock, fertilizers, or fossil fuels.<\/p>\n<p>Greenhouse gases such as carbon dioxide (CO\u2082), methane (CH\u2084), and nitrous oxide (N\u2082O) differ in strength and duration: Methane (CH\u2084), for instance, is around 80 times more potent than CO\u2082 over 20 years but breaks down after roughly a decade, while CO\u2082 lingers for centuries.<\/p>\n<p>Because of these differences, comparing soil carbon sequestration to on-farm emissions can be misleading. <a href=\"https:\/\/doi.org\/10.1038\/s41467-023-43452-3\">Rigorous climate modelling<\/a> shows that storing enough carbon in soil to fully offset emissions is simply not possible. Soil carbon storage also plateaus over time \u2013 even if practices continue \u2013 while emissions from livestock and fertilizers persist annually.<\/p>\n<p>The takeaway: Cutting emissions directly remains essential, with soil carbon playing a supporting role.<\/p>\n<p><strong>Soil is part of the solution.<\/strong><\/p>\n<p>Healthy soils are vital to Europe\u2019s climate, biodiversity, and food security. But to harness their potential, we need realistic expectations and robust science.<\/p>\n<p>By grounding agricultural policy in evidence \u2013 and understanding farmers\u2019 local realities \u2013 Europe can develop solutions that strengthen resilience, support rural livelihoods, and meet climate goals.<\/p>\n<p>Soil is part of the solution, but only as one element of a whole food-system approach to sustainability.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Authors: Alison Eagle, Jocelyn Lavallee, Renske Hijbeek Soil is one of our best allies in tackling climate change, but it\u2019s also one of the most misunderstood. Myths about what soil can (and can\u2019t) do still shape global debates. That\u2019s why scientists from Environmental Defense Fund and Wageningen University dug into the data to bring clarity. &#8230;<\/p>\n","protected":false},"author":117045,"featured_media":16248,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[120554],"tags":[70447,120542,71910],"coauthors":[120602],"class_list":["post-16244","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-agriculture","tag-carbon-sequestration","tag-european-union","tag-soil"],"acf":[],"aioseo_notices":[],"_links":{"self":[{"href":"https:\/\/blogs.edf.org\/growingreturns\/wp-json\/wp\/v2\/posts\/16244","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/blogs.edf.org\/growingreturns\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/blogs.edf.org\/growingreturns\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/blogs.edf.org\/growingreturns\/wp-json\/wp\/v2\/users\/117045"}],"replies":[{"embeddable":true,"href":"https:\/\/blogs.edf.org\/growingreturns\/wp-json\/wp\/v2\/comments?post=16244"}],"version-history":[{"count":6,"href":"https:\/\/blogs.edf.org\/growingreturns\/wp-json\/wp\/v2\/posts\/16244\/revisions"}],"predecessor-version":[{"id":16371,"href":"https:\/\/blogs.edf.org\/growingreturns\/wp-json\/wp\/v2\/posts\/16244\/revisions\/16371"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/blogs.edf.org\/growingreturns\/wp-json\/wp\/v2\/media\/16248"}],"wp:attachment":[{"href":"https:\/\/blogs.edf.org\/growingreturns\/wp-json\/wp\/v2\/media?parent=16244"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/blogs.edf.org\/growingreturns\/wp-json\/wp\/v2\/categories?post=16244"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/blogs.edf.org\/growingreturns\/wp-json\/wp\/v2\/tags?post=16244"},{"taxonomy":"author","embeddable":true,"href":"https:\/\/blogs.edf.org\/growingreturns\/wp-json\/wp\/v2\/coauthors?post=16244"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}