Abstract Desertification poses a critical threat to ecosystems and livelihoods in arid regions, where fragile landscapes are increasingly exposed to climatic variability and human pressure. This study aims to evaluate land degradation sensitivity in the Ziz Valley, southeastern Morocco, by applying the MEDALUS model within a GIS-based analytical framework. Multi-source datasets, including satellite imagery (Sentinel-2, ASTER DEM), climatic records (WorldClim), and socio-economic indicators, were integrated to derive four quality indices - soil, vegetation, climate, and management - subsequently combined into an Environmental Sensitivity Area Index (ESAI). The resulting high-resolution map shows that approximately 71.5% of the valley is highly sensitive to desertification, particularly in the southern oases of Erfoud and Rissani, where aridity, soil erosion, and overgrazing dominate. In contrast, only 12.3% of the area demonstrates low sensitivity. Validation using field surveys yielded an overall accuracy of 90%, confirming the model’s reliability. The findings emphasize the effectiveness of geospatial data integration for quantifying land degradation processes in data-scarce arid regions. This research underscores the importance of spatial information science in supporting evidence-based land management, enhancing resilience, and informing sustainable policy for vulnerable oasis ecosystems.
Tounf et al. (Wed,) studied this question.