SOIL GENESIS AND CLASSIFICATION OF AL- QARA DEPRESSION IN WESTREN DESERT

Abstract

AL–Qara depression was chosen in western desert between 40.0–40.50° E and 33.3-33.40° N to carry out this study, a semi detail survey by free lance soil survey was transects were selected to conduct this study and 12 pedons were described morphologically soil samples were collected to analysis physical and chemical properties. The results showed that the texture ranged between sandy clay loam , loamy sand to sandy loam for both transects the clay content was 79-301 gm.kg-1 while the silt content was 35–287 gm.kg-1 and the sand content was 482-960 gm.kg-1 for both transects, the density ranged between 1.1–1.8Mg.m-3 for first transect while ranged between 1.2–1.8 Mg.m-3 for second transect. The chemical properties showed that pH value ranged between 7.50-8.10 that classified as normal to slightly alkaline while the salinity value ranged between 0.2–3.7 ds.m-1, the lime content 141-547 gm.kg-1 gypsum content 10–20 gm.kg-1 the organic matter content 1–9 gm.kg-1 the cat ion exchange capacity was 7.97–14.44 Cml + .kg-1. The soils were classified due to soil taxonomy 2010 at the subgroup level and to soil series due to AL–agidi 1981, the studied soils were in tow subgroup Typic Calciargids and Typic Haplocalcids.