Soil Heavy Metals Pollution: Indexing Approach Assessment and Spatial Distribution (Assanahrah, El-Beheira Governorate, Egypt)

Agricultural soils are receiving a tremendous amount of pollutants that lead to land degradation. Therefore, it is an urgent requirement to determine and mapping the soil heavy metals content, that is the first task of soil remediation. Assanahrah area that locates at the north part of El-Beheira governorate (North of Egypt) is surrounding by many industrial activities. Therefore, it was chosen to be the pilot area to study heavy metals soil pollution.

The heavy metal concentrations (Cd, Cr, Ni, Pb, and Zn) were determined and the values for the Single Pollution Index (PlS), Nemerow Comprehensive Index (PIN), Geoaccumulation Index (PIGeo), and Improved Nemerow Comprehensive Index (PIIN) were calculated based on their values to determine the pollution level of the study area.

The results indicated that the (PIS) had the averaged values of 25.41 (Cd), 4.77 (Cr), 11.05 (Ni), 0.63 (Pb), and 2.65 (Zn) to indicate that the studied soil could be generally described as Cd, Cr, Ni-heavy polluted, Zn-slightly polluted, and Pb-no polluted.

Soil heavy metals pollution indices ((PIS), (PIN), (PIGeo), and (PIIN)) marked Cd as the most pollutant heavy metal. Cr single pollution and nemerow comprehensive indices (PIS_Cr and PIN_Cr) located the studied soil into heavy pollution class (HP). Basing on single pollution (PIS_Ni), nemerow comprehensive (PIN_Ni) and improved nemerow (PIIN_Ni) indices, the studied soils were represented Ni-heavy pollution and heavily contaminated classes. All indices revealed that Pb could be nearly considered as non-pollutant heavy metal values. PIS_Zn index located the studied soils in slight pollution class.

The maps which generated by Kriging methods of PIS aspects indicated that PIS_Ni gradient had extremely biased distribution in the west direction. Contrary, Cd, Pb, and Zn had uniform spatial distribution. PIS_Cr had a relatively biased distribution toward to the north and east.