Effects of Changes in Land Use and Land Cover on Soil Erosion Risk in the Halaba-Bilate Watershed of the Central Rift Valley, Ethiopia

Zemede Amado Kelbore ； Tewodros Assefa Nigussie

《中華水土保持學報》 54卷3期 (2023/09) Pp. 216-227

https://doi.org/10.29417/JCSWC.202309_54(3).0004

摘要

This study examined soil erosion risk under changing land-use and land cover (LULC) patterns in the Halaba-Bilate Watershed by applying the Revised Universal Soil Loss Equation (RUSLE) through a geographic information system. Rainfall erosivity, soil erodibility, slope length and steepness, vegetation cover, and conservation practices were used as inputs in the model. These inputs were processed and analyzed using ArcGIS 10.8. The annual soil loss rates in three specific years (1990, 2005, and 2020) were estimated, and the corresponding values for vegetation cover and conservation practice for the 3-year period were analyzed while other factors were kept constant. The changes in LULC patterns indicated that the area of cultivated land consistently increased at the expense of woodlands, shrublands, and grasslands over the years. Anthropogenic factors, such as frequent tillage, clearance of woodlands, removal of crop residues, and uncontrolled grazing of livestock caused the expansion of cultivated and bare lands and the shrinking of woodlands, grasslands, and shrublands in the watershed. Thus, this study concluded that LULC changes within the watershed led to a considerable increase in soil erosion during the studied period calling for the implementation of interventions that reduce the erosion rate to a tolerable level.

關鍵字

Halaba-Bilate Watershed ； Land cover ； Land-use ； Revised Universal Soil Loss Equation (RUSLE) ； Soil erosion

參考文獻

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