Remote Sensing and Geospatial Approach for Land Degradation Risk Assessment in the Costa Verde Bay Southeast of Brazil

This study assesses land degradation risk in the Costa Verde (Brazil's Atlantic Forest biome) by adapting and applying the United Nations Environment Program, Priority Actions Program Regional Activity Centre methodology for the first time in a humid tropical coastal environment by utilizing an integrated geomatics approach that includes Land Use/Land Cover change detection and NDVI trend analysis. This approach utilized multi-source remote sensing data (Landsat 5/8/9, high-resolution imagery) to map stable/unstable areas and quantify 40-year temporal dynamics (1985–2023/2025). The analysis revealed that while 87.37% of the region remains stable, 6.24% is actively degraded by sheet and rill erosion concentrated in high-risk urban-fringe zones and steep coastal slopes. A rigorous multi-criteria prioritization procedure identified 58.19km ² for immediate curative intervention and 150.74km ² for preventive protection. NDVI trend analysis (1985–2025) confirmed complex, heterogeneous vegetation dynamics characterized by an overall decline in high-vigour areas (1990–2015) followed by a recent recovery, underscoring the necessity for targeted management. Furthermore, Land Use/Land Cover change detection (1985–2023) documented a substantial 254.17% urban expansion (+ 58.01km ² ), which coincided with a slight gain in forest formation (+ 31.53km ² ) but also major contractions of sensitive ecosystems: Wetlands (− 47.79% / −6.72km ² ), Pasture (− 27.38km ² ), and Wooded Sandbank Vegetation (− 18.40km ² ). This methodology establishes a highly replicable model for erosion risk assessment in similar urbanizing tropical coastal zones globally, providing spatial outputs that directly support the implementation of the Brazilian Forest Code and municipal master plans to guide effective resource allocation for resilience planning and ecological restoration.