AbdEI-Razik,F.S.; H.M.A.EI-Tapey;M.A.EI-Tohamy
and M.A.M.EI-Bassiouy
( 2007). Physical, Chemical And Mineralogical Studies On The Soils Of Kom-Ombo Western
Plain, Egypt
Egypt. j. of Appl. Sei.,22(2B) 2007 861-877
Abstract: Kom Ombo Western plain adjacent to the Nile valley is the most prospective area for agricultural expansion in Egypt. Mineralogical, physiochemical classification and land capability classification are the main steps for this goal. Ten soil profiles representing the main gyomorphic units in the Kom- Ombo Western plain were chosen. The obtained data showed that textural of the river terraces soils ranged from sandy loam to sandy clay loam and CaC03 content varied from 5.2 to 14.6%. Soil reaction is slightly alkaline to moderately alkaline indicating that these soils are non saline to strongly saline. Soluble cations are dominated by Na+ followed by CaH , MgH and K+. the anionic composition is dominated by cr followed by sot and HC03-. Gypsum content is very low and ranged from 0.] to 1.6%.
Soils of alluvial fan have textural class varied from sandy loam to clay and CaC03 content ranged from 5.6 to ]8.2%. Soil reaction is slightly alkaline as the pH values vary from 7.5 to 7.8. The soils are non saline to very slightly saline. The dominant soiuble cations is Na~and lor Ca++followed by Mg++and K+. The anionic composition could be arranged in the order Cr>S04 =>HC03- and lor sot> Cl> HC03-. Gypsum content ranged from 0.5 to 3.1%. Soils of the Wadi have clay texture class throughout the entire profile depth. CaC03 content ranged from 8.7 to ]9.1%. The soils are lie on the slightly alkaline soils as pH values which ranged from 7.5 to 7.9. The soils are very slightly saline to stronglx saline. The cationic composition could be ranged in the order Na+> Ca+ >MgH>K+. On the other hand, cr or S04= predominate the soluble anions. Gypsum content is very low and ranges from 0.4 to 3.2%. Soil moisture characteristics are represented at field capacity, wilting point and available water. These values ranged from 7.83 to 31.9%, 2.8 to 19.65% and 2.98 to 15.7%, respectively. The high contents of field capacity, wilting point and available water of the alluvial fan and wadi soils in comparison with soils of the river terraces is a consequence of the heavy texture of the alluvial fan and wadi soils. From X-ray identification of the clay minerals it can be generally noticed that smectite (montomorillonite) is predominant clay mineral followed by kaolinite with less pronounced occurrence of illite, chlorite and vermiculite, while the identified accessory minerals are manily dominated by quartz and feldspars. Based on the obtained physical and chemical data these soils could classified into the following subgroups: Tvpic Haploclcids and Tvpic Torriorthents Application of the capability index for studied soil profiles reveal that the studied soil profiles are placed between good soil (11)and fair soils (III) grades
Keywords: ()
