Some aspects of land transformation in the western mediterranean desert of egypt

The western Mediterranean desert of Egypt has a long history of land-use. With recent development activities, land transformation is progressing at a high rate. Monitoring of changes to allow for predictions of long-term effects of these activities is viewed at three levels: (a) quantities of ecosystem components; (b) detailed distribution of patterns of land-use, vegetation and physiography; and (c) general distribution of the salient features of land. This study provides estimates at the first (a) and second (b) levels of changes in this region due to the main land-use types: grazing rain-fed farming, and irrigated farming.Grazing had little effects on soil characters, but it resulted in lower soil stability and abundance of plants and above-soil invertebrates. Irrigation resulted in water-logging and salinization, formation of calcic horizons, decrease in soil organic matter and soluble nitrogen, and in increase of above-and below-soil biota.A comparison of the distribution of vegetation and land-use in one of the sectors in 1964 and 1981, using maps based on aerial photographs and ground-truth data, indicated remarkable changes in areas of rain-fed farming, and in vegetation composition due to over-grazing.