This study focused on the soil of the Al-Khassa Sub Basin, thirty-four soil samples were collected from different areas of land use and differences in human activity.
Physicochemical properties of the soil were examined Hydrogen Potential (pH), Organic Matter (O.M), Loss Of Ignition (L.O.I), Total Organic Carbon (TOC), Cation Exchange Capacity (CEC) and Total Hydrocarbon (THC).
Hydrogen Potential (pH) showed that the soil is alkaline above seven with a mean 7.98.
Organic Matter (O.M) of the study area with a mean 1.28 % and high value found in Agricultural areas.Cation Exchange Capacity (CEC) with a mean 42.64 (cmol/kg) that is proportional to the granular size of the soil that silty clay. Both Total Organic Carbon (TOC) and Total Hydrocarbon (THC) acceptable concentration values compared to the soils of the arid region.
In the present study abundant elements (Calcium (Ca), Silicon (Si), Aluminum (Al), Magnesium (Mg), Sulfur (S), Potassium (K), Chloride (Cl), Titanium (Ti) and Phosphorous (P) ) and Trace element(Chromium (Cr), Manganese (Mn), Nickel (Ni), Zinc (Zn), Vanadium(V), Copper(Cu), Lead(Pb), Arsenic (As), Cobalt (Co), Mercury (Hg) and Molybdenum (Mo)) that have been analyzed in this study and compared with the limits to elements distribution in world soil and local study of Lesser Zab.
Elements that are higher than standard Ca, Cl, Cu, As,Hg, Mo, Zn because of excessive use of fertilizers and pesticides and poor irrigation practice and other anthropogenic sources. High concentration elements (Ni, Ca, Co) as a result of the weathering of the parent rocks, it occurs naturally in soils. Other elements that were partially higher than the standard is (K, Cr, P, S, Mg( only in dense agricultural areas.
Elements that were lower than Standard (Ti, Al, Si, Mn, V, Pb) represent the unpolluted elements at some locations the sub-basin because they are elements that increase in urban and industrial areas that are not available in the Al-Khassa Sub Basin, main activity and land use of sub basin were rural area and cultivated land.
The results of the enrichment factor (EF) and the contamination factor (CF) are calculated for contamination assessment. The Enrichment factor (EF) of the sub-basin is EF 2 depletion to minimal enrichment, indicating no or minimal pollution, but there is a real beginning of contamination of the magnesium element EF 2-5 moderate enrichment, indicating a real beginning of contamination of the magnesium element. indicating of moderate pollution due to the presence of farms that were use of magnesium sulfate fertilizers by villagers at sedan.
The results of the Contamination Factor (CF) showed that the region is low to moderate contamination
Except for the contamination factor of magnesium in Mam Rash (S22), Belgrad (S10) was very high degree of contamination of Cf > 6, and in Sedan (S25), Gurgay Shammar (S11), and Obarick (S32) was considerable degree of contamination of magnesium 3 < Cf < 6 because of the three villages was agricultural area that use of magnesium fertilizer.
Phosphor (P) contamination factor is moderate in Heon (S7), Ali Makaeel (S20) because they are villages that use phosphate fertilizers beside occurrence of poultry farms.
