The Relation Between The Soil Taxonomic Units Developed on The Geomorphic Units and Soil Fertility Status in The West Delta, Egypt.

ELEVEN soil profiles represent the different geomorphic units in.west Delta were chosen to study the relation between the soil taxonomic units developed on the geomorphic units and soil fertility status. The obtained results indicated that the taxonomic units are: 1) Typic Haplocalcids , Typic Calcigypsids developed on old Alluvial soils 2) Typic Torripsamment developed on windblown sand 3) Aquic Haplocalcids developed on Fluvio-Lacustrine soils . 4) Typic Torrifluvents and Typic Haplotorrerts developed on recent Nile Alluvial soils. 5) Halic Endoaquerts and Aridic Endoaquerts developed on Fluvio-marine soils and 6) Oxyaquic Torripsamments developed on coastal plain soils . The organic matter contents were relatively low ranged from 0.15 to 2.35 %. The cation exchange capacity ranged from 2.3 to 38.3 meq/100g , the lowest values were found in the windblown sand , whereas, the highest were in the clayey soils of Fluvio-marine.

The total contents of iron ranged from 0.2 to 1.2 %, whereas the available contents ranged from 2.4 to 57.6 ppm. The independent factors of both clay, silt and CaCO3 contributed 37.1 to 89.7 of the variations in iron in the different studied soils. The total manganese contents ranged from 170.0 to 1048.0 ppm, whereas the available contents ranged from 0.48 to 5.28 ppm. The independent factors of both clay, silt and CaCO3 contributed 22.7 to 93.4 % from the variations in Mn contents in those studied soils. The total contents of Zn ranged from 47.0 to 370.0 ppm, whereas, the available contents ranged from 0.48 to 5.28 ppm. The independent factors of clay, silt and CaCO3 were responsible 49.3 to 81.0 %. The total copper contents ranged from 22.0 to 168.0 ppm, whereas the available content ranged from 0.89 to 9.9 ppm. The variations of total copper were related to the independent factors of both clay, silt, and CaCO3, by 10.9 to 90.0 %.