الفهرس 
AcknowledgmentOnly 14 pages are availabe for public view
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Abstract
El-Farafra Oasis is located in the central part of the western desert of Egypt between latitudes 260 00’ and 270 30’N and longitude 270 20’ and 290 00’E; and covers an area of about 12000 km2. It has an irregularly triangular shape with the apex to the North’s its breadth increases as one goes south, it is bounded by steep cliffs on three sides; the east and north cliffs, although less in height is conspicuous owing to the dazzling whiteness of its precipitous face at some distance from it here is another cliff The aim of this investigation is to study the morphopedological, physical and chemical characteristics and classification of selected soils representing the different soils in El- Frafra depression. The depression could be divided into the following landforms; (plateau, depression edges and depression floor which include sand dunes (Aeolian depression); playas alluvial fans (water depression), drainage lines; piedmont, inselbergs ,Mesa (Aeolian erosion) Based on the pre-field interpretation and the information obtained during the reconnaissance field survey, thirteen soil profiles were selected to represent the identified physiographic units. Spot 4 images (acquired in 2011) and digital elevation model (DEM Fig 4) of the Oasis (developed from the SRTM data) were used to define the physiographic map in the studied area. A total of 28 soil samples, representing the different soil horizons of the selected profiles were collected, air-dried, crushed to pass through a 2 mm sieve, and stored for physical and chemical analyses. The main described elements were soil color under both dry and moist conditions using the Munsell notation, soil texture, structure, calcium carbonate and gypsum distributions. The other features such as topography of the surrounding landscape, slope, elevation and current vegetation were also described. The soils were classified as following : ((Calcisalids – Gypsisalids – Haplogypsids - Haplosalids – Calcigypsisalids - Quartzipsamment - Torryluvants – Torriorthents - Aquisalids- Gypsiargids -Torripsamment((. Gypsum and calcium accumulations were found in salinity condition in most of the investigated soil samples. The drainage problem and the groundwater presence are common in most of the depression. The challenge is to diagnose the problems scientifically and to design a suitable management system of water and soil is for the cultivation of saline resistant crops in El- Frafra depression,Western desert, Egypt.