Environmental protection areas in freshwater: remote sensing data and species diversity in large South American reservoirs

Environmental protection areas in freshwater: remote sensing data and species diversity in large South American reservoirs | 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 Research Article Environmental protection areas in freshwater: remote sensing data and species diversity in large South American reservoirs Francisco Gustavo-Silva, Diogo Martins Nunes, Amanda Menezes Ferreira, and 2 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7741491/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 Human activities negatively affect aquatic ecosystems, mainly through the contamination of water sources by urban, agricultural and aquaculture waste, leading to eutrophication. This study aims to identify the areas most affected by eutrophication in large South American reservoirs and their association with species richness to help prioritise conservation efforts. Sixty-five reservoirs over 250 km 2 were identified, mainly in Brazil. Species richness analysis showed an average of 102 species per reservoir, with variations between them, and chlorophyll indices indicated early stages of eutrophication in some regions, especially in southeastern Brazil and the Amazon. Remote sensing revealed high chlorophyll indices near urban and agricultural areas, suggesting human influence and, based on these results, priority conservation areas were identified, emphasising the protection of aquatic ecosystems. The study highlights the need for effective management measures and stricter public policies to guarantee environmental sustainability, where remote sensing was highlighted as an effective tool for monitoring eutrophication and its consequences, offering practicality and autonomy in environmental monitoring. It is recommended to increase the frequency of remote sensing evaluations to improve environmental monitoring, given its adaptability and accessibility to various contexts. limnological monitoring trophic state eutrophication geoprocessing remote sensing Google Earth Engine Full Text Additional Declarations No competing interests reported. Supplementary Files S4.png S9.png S7.png S5.png S8.png S3.png S6.png S11.png S10.png S1.png S2.png 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. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. 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-7741491","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":524936132,"identity":"880d4b61-f43a-41f4-96b2-3749eb30a073","order_by":0,"name":"Francisco 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