Determine Soil Loss Response to Agroforestry Land Use Change (ALUC) Using RUSLE Based GIS and RS in Gilgel Gibe I Catchment, Southwestern, Ethiopia

Soil erosion is a serious environmental problem, reducing land productivity and endangering people's livelihoods. Land use land cover (LU/LC) has long been thought to be the primary cause of soil erosion, but ALUC has received little attention. The aim of this study is to compare the soil loss response to ALUC with other LU/LC from 1988 to 2021 in Nadi and Yedi micro watersheds of Gilgel Gibe I catchment. Data was obtained from Landsat images (TM, ETM+, and OLI/TIRS) of 1988, 2004, and 2021 and hybrid algorithm with maximum livelihoods was used to classify it. Besides, rainfall, soil digital map, and digital elevation model were used in this study. The data was analyzed using RUSLE model in ArcGIS. As a result cultivated land was increased between 1988 and 2021, followed by agroforestry and settlement in both micro watersheds. From the entire watershed, 1027.9 and 607.7 tons/ha/year total soil loss was computed between 1988 and 2021 in Nadi and Yedi watersheds, respectively. In the Nadi and Yedi watersheds, the average annual soil loss was (64; 46.43), (66.71; 48.51), and (68.10; 45.88) tons/ha/year in 1988, 2004, and 2021, respectively. The findings showed that approximately (9%; 10%), (11%; 12%) and (12%; 11%) of the land were exposed to very severe erosion during 1988, 2004, and 2021 in Nadi and Yedi micro watersheds, respectively. The soil loss rate can be significantly decreased with the use of ALUC. Compare to other LU/LC, ALUC provides a significant impact on reducing soil loss rate. Thus, to sustainably restore degraded land and limit the rate of soil erosion enhancing agroforestry land use practices in the study area.