Modeling soil erosion for sustainable landscape management using RUSLE in the landscapes of Abaya-Chamo Sub-Basin, Ethiopia

Abstract This study aimed to assess and model soil erosion for sustainable landscape management using the Revised Universal Soil Loss Equation (RUSLE) across six diverse landscapes in the Abaya-Chamo Sub-Basin of Ethiopia’s Rift Valley Lakes Basin. The study spans six landscapes: Abaya Guangua, Arba Minch, Chencha, Hobicha, Loka Abaya, and Mierab Abaya during 2016 and 2021. The RUSLE integrates five key factors: rainfall erosivity, soil erodibility, slope length and steepness, cover management, and conservation practices. By leveraging ArcGIS software, spatial analyses were performed to estimate annual soil loss across the studied landscapes. The main results accentuate both the spatial and temporal dynamics of soil loss. In 2016, estimated soil loss ranged from 0.08 to 1652 with an average of 128.39 t/ha/year. By 2021, soil loss ranged from 0.08 to 1474.08 with a reduced mean of 63.91 t/ha/year. In 2016, Abaya Guangua experienced minimal soil loss, with 90.36% of the area seeing <5 t/ha/year. This trend improved slightly by 2021, with 91.46% of the extent falling below the same threshold. In contrast, Chencha experienced severe erosion, reaching up to 1445.73 t/ha/year in 2016 with a notable decline by 2021. In Arba Minch, soil loss increased from 265.08 in 2016 to 292.71 t/ha/year in 2021, indicating improved erosion control. The Mierab Abaya exhibited severe soil loss in 2016, with slight improvements by 2021. Ethiopia’s soil loss tolerable limit of 2–18 t/ha/year reveals that erosion in several landscapes, especially Chencha, Mierab Abaya, and Arba Minch, exceeds sustainable levels. In the studied landscapes, the spatial–temporal variability of soil loss underscores the critical importance of tailored strategies for sustainable landscape management. Decision-makers can leverage these insights to implement effective erosion control measures across diverse agroecological zones.