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The changes in land cover and usage at different scales have significant environmental consequences. Human influences on the environment are happening at magnitudes, rates, and spatial scales that were previously unheard of. The study indicates that the built-up area was he most dominant land use land cover (LULC) class from 1991 to 2021. Agriculture, bare land, vegetation and water have decreased by 41.6%, 50.5%, 47.9%, and 17.84% respectively, while built-up have increased by 141.2%. Agriculture decreased by 142.95 ha/year while bare land, vegetation and water decreased by 243.1 ha/year, 83.11 ha/year and 18.21 ha/year respectively. In contrast, the study showed that the built-up area increased by rate of 487.4 ha/year. All types of land features were converted to built-up land class, with bare land conversion being the most dominant. Agriculture was the second highest area of land that converted to built-up. Vegetation was also converted to built-up, bare land and agriculture. On the other hand, the Normalized Difference Vegetation Index (NDVI) result show that resultant minimum and maximum values ranged from -0.136 to 0.667 in 1991 while it is from -0.12 to 0.56 in 2021. The reduction in vegetation and water areas has led to environmental concerns, such as increased heat island effects, loss of biodiversity, and reduced ecosystem services. Additionally, the Normalized Difference Vegetation Index (NDVI) result shows a decrease in vegetation cover, which can further impact the environment. Therefore, it is crucial to implement effective governance policies that consider the impact of land use changes on the environment and promote sustainable urbanization practices to ensure the preservation of urban green infrastructure. [ABSTRACT FROM AUTHOR]

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]

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]