Soil Erosion Responses to CMIP6 Climate Scenarios and Land Cover Changes in the Gidabo Watershed, Ethiopia: Implications for Sustainable Watershed Management

Abstract

Soil erosion, driven by climate and land cover changes, poses a significant challenge to watershed sustainability. This study assessed historical and projected soil erosion in Ethiopia's Gidabo Watershed using climate data from an ensemble of six GCMs and Landsat images (2003, 2011, and 2019), which were classified and predicted by integrating the Random Forest classifier and Google Earth Engine, and the InVEST‐SDR model to evaluate erosion potential. Historical and future land cover change projections revealed a trend of increasing agricultural and built‐up areas, while dense vegetation exhibited a declining trend. The average annual precipitation in the baseline scenario showed an insignificant decreasing trend, whereas future projections indicated an overall increase. Soil erosion was assessed for both baseline and future periods by integrating CMIP6 GCMs (SSP2‐4.5 and SSP5‐8.5) with land cover maps. The results indicated that the mean annual soil loss increased from 18.74 t ha−1 yr−1 during the baseline period to 22.75 t ha−1 yr−1 in the 2030s and 24.76 t ha−1 yr−1 in the 2050s under SSP2‐4.5. Under SSP5‐8.5, soil erosion rates reached 23.12 t ha−1 yr−1 in the 2030s and 25.42 t ha−1 yr−1 in the 2050s. This increase was driven by agricultural expansion, reduced vegetation cover, and high rainfall erosivity. High soil erosion rates were concentrated in the southwestern and northeastern sub‐watersheds, requiring immediate conservation interventions in severely eroded areas. Reforestation, terracing, and sustainable land management are essential to mitigate soil erosion and enhance watershed resilience, providing key insights for targeted conservation strategies and sustainable watershed management.