Farmer Managed Natural Regeneration Promotes Expansion of Trees on Croplands in the Sahel

Farmer Managed Natural Regeneration Promotes Expansion of Trees on Croplands in the Sahel | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Article Farmer Managed Natural Regeneration Promotes Expansion of Trees on Croplands in the Sahel Rene Lee, Martin Brandt, Stefan Oehmcke, Chris Reij, Fernando Maestre, and 8 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-6377081/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract The expansion of trees on croplands in the Sahel has been promoted as a nature-based solution to climate challenges, particularly through Farmer Managed Natural Regeneration (FMNR). Yet large-scale assessments of cropland tree dynamics remain scarce. Here, we combine 25 years of Landsat imagery with a deep learning model trained on 9.9 billion trees to reconstruct annual tree cover at 15 m resolution across 2.4 million km² of Sahelian croplands. We find that 12% of all Sahelian trees occur on croplands and that 9.2 million hectares have gained tree cover since 1999. Gains are concentrated near villages and in regions with longstanding FMNR promotion, especially Maradi and Zinder. Areas with moderate to high FMNR intensity show greater increases than low-intensity areas. These findings provide large-scale evidence that farmer-led management has driven cropland greening, offering insights for sustainable land management, and establishing a framework for monitoring scattered trees in drylands. Earth and environmental sciences/Environmental social sciences/Climate-change adaptation Earth and environmental sciences/Environmental social sciences/Sustainability Earth and environmental sciences/Ecology/Forestry Earth and environmental sciences/Ecology/Agroecology Earth and environmental sciences/Ecology/Ecosystem services Full Text Additional Declarations There is NO Competing Interest. Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-6377081","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":508841720,"identity":"7bf2f8e7-ee0d-494a-9020-79e2482dc03e","order_by":0,"name":"Rene 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