Soil loss dynamics under different land management scenarios in the Northwestern Ethiopian highlands

Soil erosion by water is the main source of land degradation in the Ethiopian highlands, threatening agricultural productivity due to poor land management activities. This study evaluated different land management scenarios on soil loss in the North Gojjam and South Gojjam sub-basins of the Abbay basin by applying the Revised Universal Soil Loss Equation (RUSLE) using Google Earth Engine (GEE) cloud computing platform. The analysis integrated satellite rainfall, soil type, digital elevation model (DEM), flow accumulation, Dynamic World land-cover, and a soil and water conservation (SWC) distribution datasets to derive the RUSLE parameters. The current mean soil loss in the area is 32.05 t ha −1 yr − 1 , with 44.66% of the area experiencing moderate to very severe soil erosion. A severe soil loss of 40.92 t ha −1 yr − 1 on cultivated land is a direct threat to food security in the area that is known for the largest cereal producing region of the country. To evaluate the effectiveness of SWC measures, support practice (P) and cover management (C) factors were adjusted for best management and no SWC management scenarios. The results showed that in the best management scenario, mean soil loss was reduced to 16.62 t ha −1 yr − 1 , whereas under the no SWC measures scenario it has increased to 47 t ha −1 yr − 1 . The study provides baseline information for stakeholders to select SWC practices in watersheds with high soil erosion to minimize land degardation. The framework used to estimate soil loss can be adapted with minimal effort to customize for a specific region or watershed.