Climate-Induced Soil Moisture Modeling for Soil Erosion Conservation in the Choke Mountain Watershed, Ethiopia: Evidence from the Sheti Megebesh Watershed

Abstract

Abstract Land degradation driven by climate change is a critical challenge in Ethiopia’s Choke Mountain Watershed (CMW), particularly in the Sheti Megebesh micro-watershed. This study developed a Climate-Induced Soil Moisture Loss (SML) model to assess soil erosion and conservation dynamics within the watershed. Multiple datasets, from 1990 to 2024, including in-situ, reanalysis, satellite observations, seismic ray measurements, hydrometeorological records, and field observations, were investigated. Those datasets were integrated to identify erosion-triggering factors and validate the model outputs. The developed SML model successfully demonstrated strong interactions between climate variability, soil moisture depletion, and land degradation. Results showed significant increases in soil evaporation, temperature, and runoff from 1990 to 2024, while evaporation from water bodies, plant transpiration, convective precipitation, and potential evaporation declined. Increased soil evaporation, mainly associated with land-cover change, emerged as the dominant driver of soil erosion. Implementation of soil and water conservation (SWC) measures between 2020 and 2024 substantially reduced soil loss from the Sheti Megebesh micro-watershed into the Grand Ethiopian Renaissance Dam (GERD), decreasing from 230,000 to 30,000 m³. The findings emphasize that enhancing vegetation cover is essential for reducing soil moisture loss and mitigating landslide risks. Integrating indigenous knowledge with scientific approaches, supported by collaboration among communities, governments, and professionals, is crucial for sustainable land restoration and climate resilience in the Ethiopian highlands.