الفهرس 
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Abstract
Limestone plateau surrounds Assiut governorate from both east and west sides. Theis plateau is characterized by some hills and wadies. The wadies are almost flat with a gentle slope of the soil surface. The study area is located on the eastern plateau lies between longitudes 30◦ 51′ 11.12″ and 31◦ 11′ 21.09″ E and latitudes 27◦ 23′ 05.23″ and 27◦ 36′ 58.35″ N. It includes the first transect (Assiut-El-Hawata, the eastern Assiut-Cairo highway) that contains 10 soil profiles. Meanwhile, the study area on the western plateau, is located between longitudes 30◦ 36′ 41.26″ and 31◦ 17′ 2.05″ E and latitudes 26◦ 21′ 50.46″ and 27◦ 37′ 6.06″ N. It also includes the second transect (Assiut-Dairut, the western Assiut-Cairo highway) that contains 11 soil profile, the third transect (Assiut-El-Ghanaiem, the western Assiut-Aswan highway) that has 8 soil profiles and the fourth transect (Assiut- El-Kharga highway) that comprises 11 soil profiles. This study aims to evaluate the land capability of the soils of the study area that are located on the eastern and western limestone plateau and their suitability for selected crops. This objective was fulfilled through the following procedures:
1. Determination of various physical and chemical properties of some representative soil samples of the western and eastern limestone plateaus in Assiut governorate,
2. Mapping some of these soil properties,
3. Classification the studied soils according to the Soil Taxonomy,
4. Evaluation and mapping the land capability of the studied soils,
5. Assessment and mapping the land suitability of the studied soils for some selected crops, and
6. Proposing the land use future plan of these soils.
The results obtained from the current study could be summarized in the following:
I. The Elevation of the Studied soils
Using the digital elevation model (DEM), the soil surface of the first, second, third and fourth transects has an elevation range of 108 to 204 m, 116 to 222 m, 213 to 283 m and 216 to 305 m, respectively, above the sea level.
II. Soil Physical and Chemical Properties
Wide variations in the physical and chemical properties were found in the studied soils. They can be summarized in the following:
a) The soil texture is mostly coarse (mainly sand, loamy sand and sandy loam). The finer soil texture i.e. loam, and sandy clay loam is not frequently present. The gravel content of these soils ranges from 0.9 to 63.8 % by volume; the highest amount of gravels occurs in the subsurface layer of most soil profiles.
b) The bulk density varies from 1.21 to 1.97 Mg/m3. A slight increase in the bulk density was observed with depth. This may be related to a high content of the sand fraction and to their lower contents of silt, clay and organic matter.
c) The hydraulic conductivity varies from 0.07 to 65.53 cm/h with an over mean of 8.96 cm/h. This may be due to the effects of the variability of soil deposition, pedogenic and hydrologic processes.
d) The total carbonate content of these soils varies from 25.5 to 85.8 %, 13.1 to 85.9 %, 30.3 to 89.4 % and 28.0 to 93.8 % in the first, second, third and fourth transects, respectively. The high amounts of CaCO3 reflect the calcareous parent material nature of these soils.
e) The organic matter content of the investigated soils ranges from 0.03 to 1.77%. It generally decreases with depth.