Land Degradation Monitoring in the Nile Delta of Egypt, using Remote Sensing and GIS

Land degradation is one of the main problems that threaten the limited highly fertile land in the Nile Delta of Egypt. In this research, Landsat TM satellite images of 1984 and 1992, and ETM + of 2006 have been used to study the impact of urban sprawl on agricultural land in the Nile Delta. Visual interpretation using on screen digitizing and change detection techniques were applied for monitoring the urban sprawl. 42 soil profiles have been collected, morphologically described and analyzed for the study of their chemical and physical properties. The rate of salinization, and water logging were estimated following the FAO methodology for assessing land degradation. As urban sprawl is a significant degradation process, multi-temporal satellite images were used for its detection. The annual rate of salt accumulation in the soils is 0.10 dS/m, where an area of 3103.2 km 2 (or 10.8 %) has a high salinity risk. The water table is decreased by a rate of 1.85 cm per year in the Typic Aquisalids soils and 0.37 cm per year in the Typic Calcigypsids soils. The water logged areas cover 7461.3 Km 2 (or 25.9 %) concentrated in the Northern part of the Delta. The results show that a total expansion of urban area was 202.6 Km 2 between 1992 and 2006 of which 37.41 km 2 were converted from the alluvial fertile soils and 165.2 km 2 from cultivated desert fringes. It can be concluded that salinization and the urban sprawl are the dominant degradation process in the Nile Delta.