Soil erosion is the main drivers in the world and Ethiopia in particular. This study has been conducted at Dijo watersheds in the Rift valley Basins of Ethiopia to estimate soil erosion rate and identify erosion hotspot areas for proper planning using Geographic Information System and Universal Soil Loss Equation adapted to Ethiopian condition. 64 years mean annual rainfall data for estimating erosivity factor, digital soil map for estimating soil erodibility factor, Digital Elevation Model for estimating topographic (LS) factor, Land use land cover for cover factor detection from Ethiopian ministry of water resources. The result reveals that the soil loss ranges from 0 ton/ha/year in flat slope to 38.09 ton/ha/year from steep slopes. The average soil loss rate is 2.2 tons per hectare per year and has been classified into three erosion severity classes as very low, low and moderate. The result also reveals that most of the watershed erosion severity evaluated under very low and low soil erosion severity classes covering 97.3% of the watershed areas which is due to the effect of mixed plantation of various tree and terraces. However, moderate soil erosion in the upper parts of the watershed could be due to the inherent characteristics of vertisols, lack of vegetation cover and terraces which should be given first priority for conservation interventions. From the gross soil erosion, 43,762 ton/year sediment yields have been estimated at watershed outlet. Policy aim at keeping land productivity will need to focus to reduce low and moderate soil erosion through terracing, inter-cropping, contour farming, strip cropping, conservation tillage, mulching and biological stabilizers based on their slope range, soil type and land use type. The current finding on erosion was evaluated based on the past 10 years land use land cover scenario; therefore, soil erosion might be reduced if the current land use land cover scenario considered. Finally, the integration of USLE and GIS is an effective tool in mapping the spatial distribution of soil erosion from the entire watershed. The moderate and low soil erosion severity areas should be managed through terracing, inter-cropping, contour farming, strip cropping, conservation tillage, mulching and biological stabilizers based on their slope range, soil type and land use type. Free grazing and cultivation of steep slope(Northern parts) contributed for moderate soil erosion in the watershed should be managed by cut–carry system, limiting the number of cattle units to be grazed in the specific plot of land and leaving the marginal steep slope areas with no ground covers for natural regeneration. Finally, the current finding on erosion was evaluated based on the past 10-year land use land cover scenario. Therefore, the soil erosion could be reduced if the current land use land cover scenario is considered.

Conservation tillage is a promising tillage practice for enhancing soil moisture conservation. The objective of the study is to evaluate conservation tillage methods on soil moisture and maize grain yield in Silte and Gurage zone of Ethiopia. No tillage, one-time tillage, two times tillage, and conventional tillage methods were evaluated. The treatments were laid out in randomized complete block design with three replications for three consecutive years (2018–2020). Besides soil moisture data, selected physical and chemical soil properties were collected. Economic analysis was also computed for each tillage method to select cost effective conservation tillage methods. The result reveals, conservation tillage methods had better soil infiltration and soil moisture content relative to conventional tillage. There was no significant difference between treatments in soil organic carbon, total nitrogen, and phosphorus in the top 10 cm in the Mareko site. However, except for phosphorus, significant differences (p < 0.05) between treatments in soil organic carbon and nitrogen were detected in the 10–20 cm depth. The maize yield and yield components are significantly affected by treatments at the Mareko site and not significant at Mito. The results support that conservation tillage tested in this study could contribute to the improvement of soil properties and maize yield in study sites.

In Ethiopia, particularly Southern Regional State dry land crop productivity is majorly influenced by low soil moisture stress. The current study has been conducted to evaluate the effect of intercropping maize with legumes covers on Soil Moisture improvement at Misrak Azerinet Berbere woreda. Seven treatments evaluated were vetch with maize, lablab with maize, vetch only, lablab only, and maize only. The experimental design was in a randomized complete block design (RCBD) with three replications in a permanent plot. Disturbed soil samples were collected from the intra-row spacing from both intercropped and non-intercropped plots from the depth of 0–20 cm and composited for soil moisture analysis. The yield and biomass of maize and legume shrubs have been collected. The Land Equivalent Ratio (LER) was computed to evaluate the land productivity of intercropped combinations. The result reveals that in both years, yield, biomass, and soil moisture content were not significant (p > 0.05) at a statistically significant level. After crop harvest, maize with lablab has better soil moisture relative to other combinations (first year). In both years, the soil moisture content in the soil was reduced in the sole crop of maize compared with sole vetch. However, the soil moisture content in the soil was increased in maize intercropped with lablab in both development stage and after harvest compared with maize intercropped with vetch. Both legume shrubs under mono and intercropped conditions conserve soil moisture relative to maize under mono cropped conditions. This implies the benefit of legume shrubs on soil moisture conservation both planted under mono cropped conditions and intercropped conditions. It is concluded that the combination of intercropping maize with legume shrubs could substantially increase soil moisture conservation and improve the overall land productivity. Therefore, for maximum maize production, farmers in the area should plant maize with a combination of vetch and lablab. Additionally, farmers should practice double cropping with the residual soil moisture from legume and its combinations.

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