Effects of Soil and Water Conservation Structures on Selected Soil Physicochemical Properties: The Case of Ejersa Lafo District, Central Highlands of Ethiopia

Land degradation in the form of soil erosion and fertility depletion is the major environmental problem in Ethiopia. However, to curb this problem, soil and water conservation (SWC) structures are commonly practiced in many rural parts of Ethiopia. This study was conducted to assess the effects of SWC structures on selected soil physicochemical properties in Ejersa Lafo district. For this study, two kebeles (peasant associations) were selected purposively from the district based on the severity of soil erosion and information on SWC practices. The research design employed in this study was systematic, randomized, complete block design. A total of 12 composite soil samples were collected from the depth of 0 to 20 cm at two subwatersheds, namely, Jamjam laga batu and Koriso Odo guba with SWC and without SWC structures at three landscape positions. All the soil samples were analyzed following the standard and recommended procedures. The effect of independent variables (SWC practices and landscape positions) on the dependent variables (soil properties) was statistically tested using the SPSS computer program 21. In this study, most of the selected soil physicochemical properties were affected by watershed management intervention (SWC) structures. Soil moisture content (SMC), clay, pH, electrical conductivity (EC), total N (TN), available (AP), available K (AK), and organic carbon (OC) were higher in the subwatershed treated with SWC structures (conserved), whereas bulk density, silt, and sand were higher in the subwatershed without SWC structures (nonconserved). Most of the selected soil chemical properties were significantly varied (p