Three sets of satellite data were utilized to outline and monitor the waterlogging problems along the Wadi El Tumilate basin. These data include Thematic Mapper image for year 1984, Enhanced Landsat Thematic Mapper im...Three sets of satellite data were utilized to outline and monitor the waterlogging problems along the Wadi El Tumilate basin. These data include Thematic Mapper image for year 1984, Enhanced Landsat Thematic Mapper image for year 2000 and SPOT-4 image for year 2008. Supervised classification using the maximum likelihood approach has been performed. A number of 6 classes were observed at the study sites including, Niledeposits and cultivated areas, surface water and water logged areas, salt crust, Quaternary playa deposits, fluviatile and lacustrine deposits and Miocene (gypsum and carbonate) deposits. Water logged areas expanded from9.1 km2 inyear 1984 to18.8 km2 inyear 2000 to25.3 km2 inyear 2008, with a rate of0.7 km2/year. At the same time, vegetation cover shows an increase from453 km2 inyear 1984 to719 km2 inyear 2008. The integrated data used by Geographic Information Systems specified factors controlling waterlogging problems, which are: topography, drainage pattern and water flow direction, excess of irrigation water, deficiency of drainage system, presence of impermeable clay lenses and lineaments direction. Groundwater modeling including GMS and MODFLOW programs were processed to manage waterlogging problem. Using of underground tile drain along the eastern portion of Wadi El Tumilate basin and dewatering wells along the western side was recommended to obtain the highest monetary return from the drainage investment.展开更多
文摘Three sets of satellite data were utilized to outline and monitor the waterlogging problems along the Wadi El Tumilate basin. These data include Thematic Mapper image for year 1984, Enhanced Landsat Thematic Mapper image for year 2000 and SPOT-4 image for year 2008. Supervised classification using the maximum likelihood approach has been performed. A number of 6 classes were observed at the study sites including, Niledeposits and cultivated areas, surface water and water logged areas, salt crust, Quaternary playa deposits, fluviatile and lacustrine deposits and Miocene (gypsum and carbonate) deposits. Water logged areas expanded from9.1 km2 inyear 1984 to18.8 km2 inyear 2000 to25.3 km2 inyear 2008, with a rate of0.7 km2/year. At the same time, vegetation cover shows an increase from453 km2 inyear 1984 to719 km2 inyear 2008. The integrated data used by Geographic Information Systems specified factors controlling waterlogging problems, which are: topography, drainage pattern and water flow direction, excess of irrigation water, deficiency of drainage system, presence of impermeable clay lenses and lineaments direction. Groundwater modeling including GMS and MODFLOW programs were processed to manage waterlogging problem. Using of underground tile drain along the eastern portion of Wadi El Tumilate basin and dewatering wells along the western side was recommended to obtain the highest monetary return from the drainage investment.
