Assessment and quantification of average soil erosion using RUSLE and geospatial modeling for sustainable Land management over Melka-Sedi Catchment, Ethiopia.

Abstract Soil erosion is a significant worldwide threat, with far-reaching adverse effects on the environment. The general objective of this study is to assess the spatial average soil loss, identify high-risk areas, and visually represent variation of soil loss from Melka-sedi catchment employing Revised Universal Soil Loss Equation (RUSLE) and geospatial modeling. RUSLE computes average soil erosion based on five significant factors: rainfall erosivity, topography, cover management, soil erodibility, and support and management activities. The spatial distribution of all factors and the final RUSLE estimations were performed using the ArcGIS workspace. The results of this study indicated that the annual soil loss from the catchment ranged from 0 to 4,742 tons ha− 1 year− 1. The area was categorized into five subclasses of soil loss severity zones: high, sub-high, moderate, sub-low, and low. Most of the land, 209,561.24 hectares (77.25%), falls into the low erosion category, while 36,093.65 hectares (13.05%) are classified as sub-low erosion, 13,992.43 hectares (5.15%) are considered moderate erosion, 7,363.25 hectares (2.71%) as sub-high erosion, and 4,249.98 hectares (1.56%) as high erosion. Overall, the total annual soil loss throughout the study area was 1,098,931.5 tons. More than 4% of the land within a catchment requires urgent conservation activities. It is concluded that significant soil erosion is found in the catchment, and it is recommended to prioritize erosion-affected areas in the catchment and apply conservation practices to achieve sustainable watershed management within the catchment. This study provides useful information for directing actions to reduce erosion, prevent significant land degradation, and achieve sustainable land management.