Integration of Terrain, Thematic Mapper and Soil Quality Data for Surface Hydrology, Water Erosion and Land Suitability Modeling: NW Coast, Egypt

摘要

AT A REPRESENTATIVE area at Omyed, NWC, the present study aims to integrate GIS and RS technologies with soil qualities data in assessing and modeling the rain- runoff relationship, the water erosion hazards and the land suitability for specific uses.The GIS-modeling capability was used to integrate the analysis outputs of thematic mapper image, of digital terrain, and of soil qualities to model the following : 1, Rainfall-Runoff: The rainfall-runoff relationship was estimated by using the curve number method The study indicated that a total number of 46 cisterns are required for collecting and reserve 4121 m~3 in November and 19202 m~3 in January of runoff water for eleven natural undisturbed watersheds. 2,Water Erosion Hazards : The revised universal soil loss equation was used .The analysis showed that, about 506.23 km~2 are subject to erosion rate of less than 20 ton/ha/year and about 153.31 km~2 are subject to erosion rate of more than 20 ton/ha/year for the maximum erosion hazard scenario.For the current erosion hazard scenario 567.26 km~2 are subject to erosion rate of less than 20 ton/ha/year and about 92.28 km~2 are subject to erosion rate of more than 20 ton/ha/year. 3. Land suitability for specific uses : MicroLEIS land evaluation model linked with GIS was used. The capability evaluation indicated that, about S~2 : 178.49 km~2 , S3 : 188.09 km~2, and N : 296.77 km~2. The irrigated agriculture suitability for 12 specific land gave for olive about 9.67 km~2 as S~2 and 7.86 km~2 as S3for olive, for peach and citrus about 11.05 km~2 as S3 and 6.39 km~2 as S4 and for Wheat, Corn, Alfalfa, Sunflower, Cotton, soybean, Sugar Beat, Potato and Melon about 17.44 km~2 are S4. The rainfed agriculture suitability evaluation indicated that, about 366.58 km~2 are class II, 292.35 km~2 are class III and 4.42 km~2 are class IV for rainfed agriculture.