ASSESSMENT OF THE IMPACTS OF LAND USE AND LAND COVER CHANGES ON SOIL EROSION IN BENSA WOREDA, SIDAMA REGION

Abstract Recently, there has been a growing global concern about the impact of changes in how land is used and covered on various natural and manmade resources, especially soil resources. This study specifically focused on analyzing the changes in land use and land cover and the associated risks of soil erosion in Bensa woreda, Sidama region, between the years 2003 and 2023. The data for this study were collected through field surveys and secondary sources. We obtained Landsat images from 2003, 2013, and 2023 and classified them using supervised classification methods. The study found significant changes in how the land was used and covered over the twenty-year period. Agroforestry and bare lands were the dominant land use types, but by 2023, there was a noticeable increase in settlement areas. Agroforestry decreased from 86.48% in 2003 to 77.01% in 2023, while the area of bare land increased from 6.55% to 12.99% during the same period. Built-up land expanded from 0.09% to 1.62%, and farmland increased from 2.66% to 5.07%. However, forests experienced a decrease in area from 4.9% to 2.7%. These changes highlight the dynamic nature of land use in the study area, with different types showing varying degrees of change. Using the RUSLE model in a GIS platform, the study determined the impact of land use and land cover changes on soil erosion in the study area during the three periods. The average annual soil loss rates for the years 2003, 2013, and 2023 were found to be significantly higher than the tolerable range. Agroforestry, bare land, and farmland consistently showed increasing soil erosion rates in the study area. The findings emphasize the importance of monitoring changes in land use and their effects on soil erosion. Additionally, the spatial analysis revealed that converting agroforestry in relatively flat areas to urban areas and extensive cultivation practices on erosion-prone soils were the main factors contributing to the increased risk of soil erosion in the study area. Moreover, the results indicated that converting other land use and land cover categories to farmland and open areas posed the greatest threat to soil erosion. It is crucial to prioritize interventions related to land use planning, management, and soil conservation practices in the southwest portion of the study area, which faces high erosion risks, to ensure the conservation of valuable resources.