The Effects of Fanya Juu Terraces on Soil Physicochemical Properties in the Context of Sustainable Crop Production and Erosion Control in Southern Ethiopia

ABSTRACT Severe soil degradation in Ethiopia often leads to unproductive wastelands in hilly areas. Consequently, a number of soil and water conservation (SWC) practices have been implemented to address this issue. Among these, the Fanya juu terrace stands out as one of the most widely adopted SWC practices in the cultivated lands of the study area. However, field data remain insufficient to assess the effects of Fanya juu terraces on soil under specific site conditions for effective land management. Therefore, this study aimed to evaluate the impact of the Fanya juu terrace on selected soil physicochemical properties in southern Ethiopia. Cross‐sectional data were gathered based on randomly collected soil samples from farmlands with three different conservation ages (non‐conserved, 5‐year, and 10‐year‐old Fanya juu terrace conservation) along three slope gradients. A total of 90 soil samples were collected from the top 20 cm of soil, and their physical and chemical properties were determined. There were significant differences ( p ≤ 0.05) in soil pH, organic carbon (OC), total nitrogen (TN), available phosphorus (Av.P), exchangeable potassium (K + ), and cation exchange capacity (CEC) between non‐conserved farmland and older Fanya juu terraces. Non‐conserved farmland had higher sand content and bulk density compared to those with Fanya juu terraces. In contrast, clay, silt, moisture content (MC), pH, OC, TN, Av.P, K + , and CEC were higher in the 10‐year‐old Fanya juu conserved soils than in the 5‐year‐old Fanya juu terraces and non‐conserved soils. Moreover, these characteristics were higher in the lower slope classes than in the middle and upper slope classes. These results indicate that the implementation of Fanya juu terraces improves soil physicochemical properties by effectively reducing soil erosion. In addition, the beneficial effects are more significant with the increasing age of Fanya juu terraces, although this relationship is influenced by slope position.