Mapping Soil Erosion Risk Using Rusle, Gis and Remote Sensing Techniques

Abstract

Soil erosion is one of the major causes of land degradation in arid and semi-arid areas like Ethiopia, including Tigray Highlands, which is highly affected by the risk of desertification. Tackling on-site effects of soil erosion requires understanding of the rates of soil loss as well as identification of the major controlling factors that accelerate or slow down these processes. The study aims to quantify the soil loss by erosion process and to specify the main factor affecting the Erosion development in the study area. The Study area was Kilte Awulaelo District which is situated in the eastern part of Tigray region, Ethiopia. Soil erosion models (such as RUSLE) use mathematical expressions to represent the relationships among various factors and processes occurring in the landscape. The RUSLE analysis has been applied to this case study. ArcGIS™ and Excel software were used for all the calculations procedures of RUSLE values and to produce the soil erosion risk map. The final quantitative RUSLE values showed the loss quantity of soil in t/ha/year, ranging from less than 1 to very high soil loss rates (223.6 t/ha/y). The data shows also that Topography (LS) factor was the most effective factor controlling the erosion process followed by the support practices (P) factor. The study showed that stone bands are successful management practice to conquer the soil erosion dilapidations. This study demonstrates that Remote Sensing and GIS are effective tools in generating spatial and quantitative information on soil erosion studies and risk assessment mapping.