ESTIMATION OF SOIL EROSION HAZARD IN SOME WADIS OF THE NORTH WESTERN COASTEGYPT USING RUSLE MODEL AND GIS

Assessment of soil erosion loss is useful in the development of plans and protection for watershed and basins, causing this phenomenon of land degradation and loss of nutrients and decrease of water available to plants. RUSLE model integrated with GIS has been used to estimate soil loss in Wadi Umm Ashtan and Wadi Umm El-Rakham basins located in the North West Coast (NWC) of Egypt. Annual rainfall data, digital elevation model (DEM), land-use classification map and soil map were used to generate the RUSLE parameters such as rainfall erosivity factor (R), Length slope factor (LS), soil erodability factor (K), vegetation cover factor (C) and erosion control factor (P). Depending on the results obtained, it was found that the highest value of predicted soil erosion of wadi Umm Ashtan is 562.8 tone/ha/year. As for wadi Umm El-Rakham, the highest value of predicted soil erosion is 211.6 tone/ha/year. According to erosion hazard classification suggested by Singh et al. (1992), Soil erosion of Wadi Umm Ashtan and Wadi Umm El-Rakham basins are classified into 6 classes: Slight (99.4% and 99.3% of total area respectively), moderate (0.4% and 0.6% of total area respectively), high (0.1% and 0.1% of total area respectively), with very small areas of very high, severe and very severe classes. The results can certainly aid in implementation of soil management and conservation practices to reduce the soil erosion in Wadi Umm Ashtan and Wadi Umm El-Rakham basins.