Cartographie par télédétection de la dynamique et de la dégradation de la végétation du site Ramsar 1018 (Sud-Bénin) de 2000 à 2025

Abstract

Vegetation cover degradation is today a major environmental issue for wetlands in general, and for Ramsar Site 1018 located in southern Benin in particular. It currently represents a significant threat to the ecological and socio-economic balance of the landscape (agricultural exploitation, urbanization, fuelwood harvesting, and logging). The objective of this study is to assess the level of vegetation degradation at this site. The methodology adopted is a geographical approach based on the use of remote sensing data (multispectral satellite imagery), Geographic Information Systems (GIS), Multi-Criteria Evaluation (MCE), and the Analytical Hierarchy Process (AHP). The results obtained reveal significant and unevenly distributed vegetation degradation within Ramsar Site 1018. Specifically, areas with very high (14.25%) and high (48.01%) degradation together account for 62.26%, representing more than half of the study area, where vegetation cover is subject to anthropogenic pressures mainly linked to rapid urbanization and intensive agricultural activities. Areas with moderate (19.50%) and low (18.24%) degradation correspond to surfaces where wetland vegetation is still relatively preserved, despite environmental pressures related to climate change. The PSIR analysis identified extensive agriculture (40%), deforestation (25%), urbanization (20%), and bush fires (15%) as the main pressure factors. In response to this situation, priority actions consistent with the commitments of the Ramsar Convention are recommended: ecological restoration (35%), sustainable agricultural management (30%), conservation and protection (20%), and awareness-raising among decision-makers (15%).