The degradation of aquatic ecosystems is a widespread and concerning phenomenon in southern Benin, where most of the country’s wetlands are located. This study analyzes the impacts of anthropogenic activities and environmental degradation in the Toho Lake watershed in southern Benin through a combined approach of spatial analysis and field surveys.
The results reveal that the main identified pressures are artisanal fishing, agriculture, deforestation, and urbanization. The expansion of agricultural land (+2.72%), the increase in bare soil (+25.49%), and the decline of gallery forests (– 4.5% per year) indicate a progressive degradation of the watershed. The hemeroby index highlights the growing artificialization of natural environments, which negatively affects environmental quality and the sustainability of ecosystem services (biodiversity, water quality, and hydrological regulation). In view of these findings, it is essential to adopt integrated management approaches that combine geospatial tools, ecological restoration, and the active involvement of local communities.