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Land degradation is a serious problem for Ethiopia's productive capacity for land resources. To reverse these environmental dynamics, slow down soil degradation, and raise smallholder farmers’ agricultural yields, watershed management interventions have been implemented in Ethiopia since the 1980s. Thus, this study was aimed at assessing the effects of watershed management interventions on soil erosion reduction by using the InVEST model in the Yezat watershed, north-west Ethiopia. The modified ecosystem services valuation model (InVEST) was employed to evaluate soil loss reduction in response to watershed management interventions. Different watershed management intervention scenarios (baseline scenarios, afforestation scenarios, soil/stone bund scenarios, and integrated scenarios) were also applied to evaluate the effectiveness of watershed management interventions on soil loss reduction. The result of the study indicated that a high amount of mean annual soil loss (111 tons ha−1 year−1) was observed in 2000 in the study area due to the expansion of cultivated land and built-up area at the expense of forest, shrubland, and grassland. However, the mean annual soil loss decreased from 111 tons per year in 2000 to 79 tons per year in 2021 in the study area due to different watershed management interventions. Additionally, at the baseline scenario, the estimated mean annual soil loss of the watershed was 111 tons ha-1 yr-1. Conversely, it was reduced to 49.3 ton ha-1 yr-1 in the reforestation scenario, 16.49 ton ha-1 yr-1 in the soil bund scenario, and 8.26 ton ha-1 yr-1 in the integrated scenario. The watershed covered by the very severe soil erosion severity class was reduced in all watershed management intervention scenarios. Among others, the highest soil erosion reduction was observed in the integrated (bio-physical) scenarios of watershed management interventions. Therefore, watershed management interventions and scenarios were the best mechanisms for soil loss reduction. [ABSTRACT FROM AUTHOR]

Soil degradation exacerbates the depletion of soil resources and poses a threat to agricultural productivity and environmental sustainability. To address this issue, initiatives focusing on soil and water conservation (SWC) were carried out in the Tana Basin watershed located in Ethiopia. However, their spatial distribution, status, and effects of SWC activities on soil erosion were not evaluated in the entire study watershed. Thus, a revised universal soil loss equation (RUSLE) was adopted to identify soil erosion prone areas and evaluate the effect of SWC activities on soil erosion in Ethiopia. The finding shows the average soil loss of the catchment is 18.65 t/ha/year (moderate), and the detached and transported soil is 7934 tons/year. By implementing bunds in croplands and restricting grazing in degraded bushlands, it is feasible to reduce current soil erosion by 47% of the overall soil loss. The catchment area shows varying degrees of soil erosion, with a minimal rate in some areas, while others experience slight, moderate, severe, and very severe rates of soil loss, which make up 15.5%, 13.3%, 12.8%, and 10.9%, respectively. The prediction efficiency of the RUSLE using ground‐measured soil erosion data results (R2 = 0.90) revealed reliability. Consequently, the initial situation (soil bund and enclosure) results in a 47% reduction in erosion, the second situation involves increased expenses in materials and labor by 53% compared to the first scenario, and the third situation converts all deteriorated bushlands into forest land by 10%. Therefore, recommended SWC practices should be adopted in the Kecha and similar watersheds to minimize soil erosion and sustain soil productivity. [ABSTRACT FROM AUTHOR]

In Ethiopia, watershed management interventions have been implemented since the 1980s to curb land degradation and improve soil moisture potential. Thus, this study was aimed at evaluating the impacts of watershed management interventions on the soil moisture potential, soil texture, and bulk density of the study area. A quasi-experimental research design was employed for this analysis. A total of 99 soil samples were collected for soil moisture, soil texture, and soil bulk density laboratory analysis at a depth of 0–20 cm. Moreover, a one-way ANOVA was used to evaluate the mean variances of soil moisture, soil texture, and bulk density attributes among each treatment group in the study area. Univariate analysis was also applied to evaluate the overall effects by following the General Linear Model (GLM). The results of the study showed that a statistically significant difference (P≤ 0.05) was observed in soil moisture status between the treated (physical and bio-physical) and untreated (controlled) farmlands in each cycle of soil moisture status. At each time of observation, bio-physical types of watershed management interventions had a high moisture status (43.6%), followed by physical types (38.63%) of watershed management interventions, while low amounts of soil moisture (30.16%) were observed in untreated (control) parts of the watershed. The correlation between soil texture and soil moisture content indicates that soil with a high moisture content has a fine soil texture. Whereas soil with a low moisture content has a coarser texture. Both soil moisture and soil bulk density were also significantly affected due to watershed management interventions in the study area (P ≤ 0.05). Therefore, the findings revealed that watershed management increased soil moisture potential and decreased the soil bulk density of the watershed. There is also a strong negative correlation between soil moisture and soil bulk density [r = −0.81, n = 27, p<0.005]. [ABSTRACT FROM AUTHOR]

The aim of this study was to determine how soil bunds affected important soil characteristics based on the soil's reflectance in Aba Gerima, an Ethiopian midland of the Abbay River Basin. Soil samples were collected from 0 to 30 cm of the soil depth in 48 plots for soil texture, pH, organic carbon (OC), total nitrogen (TN), available phosphorus (av. P), and available potassium (av. K). Using a spectroradiometer, we evaluated the reflectance of soils that had been air‐dried, pulverized, and sieved. To locate and forecast the change in soil parameters, we employed regression modeling. We identified and predicted soil properties using the models, which were evaluated by the coefficient of determination (R2) and root mean square error. Soils from bunded plots had less reflection. Higher amounts of clay (61%), OC (2.30%), av. P (13.72 ppm), and av. K (116.55 mg/kg) were found in bunded plots. For calibration data, R2 was 0.93, 0.83, and 0.82 for clay, sand, and OC contents, respectively. Spectroradiometry could therefore complement conventional soil analysis. More study is needed to enhance spectroscopy's prediction performance. Core Ideas: Soil bunds improved the clay, silt, organic carbon, and potassium contents of soils.Bunded soils recorded less reflectance.Low soil reflectance indices show increased soil quality.Spectroscopy could better characterize soils as compared to convectional one. [ABSTRACT FROM AUTHOR]