Impact of the Hydro-Geomorphological Environment on Soil Erosion Susceptibility Using Weight of Evidence and Sensitivity Analysis in the Kumari River Basin, India

Soil erosion constitutes a pressing concern with far-reaching implications for agricultural productivity, hydrological infrastructure, and ecological systems. To effectively address this pervasive geomorphological hazard, it is imperative to elucidate the conditioning factors associated with hydro-geomorphological dynamics. This research aims to examine the impact of twelve hydro-geomorphological determinants on soil erosion susceptibility within the Kumari river basin, a region where moderate to severe erosion poses substantial threats to agriculture and the environment. Employing the Weight of Evidence and sensitivity analysis techniques, the study identifies soil erosion susceptibility zones and assesses the relative influence of each determinant. A total of 405 soil erosion patches are discerned, with 70% (284) allocated for model development and 30% (121) designated for validation. The resulting soil erosion susceptibility map unveiled a region encompassing 255.20 km² (13.01%) as being susceptible to very severe to severe erosion. The Area Under Curve (AUC) of Receiver Operating Characteristic (ROC) technique is executed, revealing a map accuracy of 76.40%. The analysis highlighted the paramount significance of the geomorphology parameter in influencing soil erosion. Among the diverse geomorphological features present in the study area, the pediment demonstrated a heightened susceptibility to soil erosion. The study emphasizes combining ecosystem-based strategies with community engagement and structural measures for effective soil erosion control. It also recommends including climate modelling and socio-economic analysis in erosion assessments to improve future scenario predictions.