Assessment of Water Erosion in the Semi-Arid Oued Beht WatershedUsing Satellite Data and Comparative Modeling Approaches

Water accumulation is a critical challenge in arid and semi-arid regions, significantly degrading soil quality and threatening land sustainability. This study focuses on the Oued Beht watershed in Morocco, covering 6,200 km², representative of semi-arid geographical conditions. Using satellitebased Earth observation data, including Landsat 9 and SRTM, this research assesses water erosion by comparing two models: PAP/CAR, a qualitative approach, and RUSLE, a quantitative model.
Key datasets, such as NDVI, slope, and land use, were extracted from satellite imagery to calibrate and validate the models. For the RUSLE model, the rainfall erosivity factor (R) was estimated using two distinct methods. The first applies the formula developed by Renard and Freimund (1994), which links annual precipitation to erosivity. The second employs a modified formula by Rango and Arnoldus (1987), adapted to Moroccan conditions, using monthly and annual precipitation to estimate erosivity.
Rainfall data covering 65 years (1958–2023), obtained from 23 meteorological stations, were utilized to ensure robust and reliable analysis. By comparing the performance of these two RUSLE methods with the PAP/CAR model, this study aims to determine their respective effectiveness in
evaluating erosion risks.
The findings contribute to advancing knowledge on erosion processes, offering valuable insights for sustainable land management practices and mitigating land degradation in semi-arid environments. This research underscores the critical role of satellite data and modeling in
addressing natural hazards, aligning closely with the conference’s focus on leveraging Earth observation technologies for risk assessment and management.