GIS-Based Spatial Modeling of Soil Erosion and Conservation Priority Mapping Using RUSLE in the Diko Watershed, Northeastern Ethiopia.

Abstract Soil erosion remains a major environmental challenge affecting sustainable agriculture and land resource management in Ethiopia, particularly in highland regions. This study aimed to assess the spatial distribution of soil loss and prioritize sub-watersheds for targeted soil and water conservation in the Diko watershed, northeastern Ethiopia. An integrated approach combining Geographic Information Systems (GIS), Remote Sensing (RS), and the Revised Universal Soil Loss Equation (RUSLE) was applied. Multi-source datasets, including Sentinel-2 imagery, Digital Elevation Models (DEM), rainfall records (2002–2023), and field-based soil data, were used to derive key erosion factors. The estimated annual soil loss ranged from zero to 154.409 t ha⁻¹ yr⁻¹ levels to 154.409 t ha⁻¹ yr⁻¹, with a mean value of 3.06 t ha⁻¹ yr⁻¹. Although the average soil loss is below the tolerable threshold, significant spatial variability was observed, with severe erosion concentrated in steep slopes and poorly managed lands. Sub-watersheds were categorized into priority classes to guide conservation planning. The findings highlight the importance of spatially explicit erosion assessment for effective resource allocation and sustainable watershed management.