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

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.