The objectives of this study were to determine the amounts of total and available heavy metals in some Egyptian soils and their relation with some soil properties. Five soil profiles; two from Kafr El-Sheikh Governorate located at south Kafr El-Sheikh city and south Baltim city to represent Delta soils and three profiles from El-Beheira Governorate located at Housh-Eisa, Abo El-Matameir and Mariut to represent Delta fringes soils. These profiles were chosen to cover as far as possible the Delta soils (Fluvial and Lacustrine soils) and Delta fringes soils (Sandy calcareous and Alluvial calcareous soils and Calcareous soils) at the northern part of Egypt.
Data showed that, the surface layers of Delta soil contained higher amounts of total and available Cu, Ni, Cd and Pb than the subsurface soil layers and decreased with depth. The contents of total Cu, Ni, Cd and Pb in Delta soils varied from 246.3 to 102.5, 186.3 to 100.0, 9.85 to 1.85 and 175.0 to 60.0 mg/kg soil, respectively in the surface layers. The corresponding values of the DTPA-extractable metals were 11.8 to 11.4, 0.78 to 0.8, 0.21 to 0.023 and 0.37 to 0.22 ppm, respectively.
The average content of total Cu, Ni, Cd and Pb for Delta fringes soils varied from one metal to another and also from one soil to another. Therefore, these metals can be arranged according to their contents in the order: Cu > Pb > Ni >Cd. The contents of total Cu, Ni, Cd and Pb in Delta fringes soils varied from 57.5 to 120.0, 62.5 to 95.0, 2.3 to 4.65 and 39.5 to 69.5 mg/kg, respectively for the surface layers. The alluvial calcareous soils recorded the lowest amounts of heavy metals; whereas sandy calcareous soils recorded the highest ones. The available amounts of these metals varied relatively in narrow range and the averages were 2.11, 0.16, 0.035 and 0.20 mg/kg soil for Cu, Ni, Cd and Pb, respectively.
The values reveal that metal content is mainly dependent on soil parent material, organic matter content and cation exchange capacity. Highly positive significant correlations were found between clay and silt % with total and available heavy metals, and also between organic matter content and total and available metals except available Cu. Cation exchange capacity showed highly significant correlations with either total or available metals. On the other hand, negative correlations were found between calcium carbonate and total and available metals. It can be concluded that, the heavy metal contents in the studied soils are affected mainly by the geochemical sources or soil parent material.