Assessment of Trace Elements Concentration in Soils of the Hashtgerd Area Using Geochemical and Multivariate Statistical Methods, Alborz Province, Iran

Concentrations of trace elements (As, Co, Cr, Cu, Mo, Ni, Pb, V and Zn) were studied in 160 soil samples in the Hashtgerd area. Comparison of mean concentration of the trace elements in both agricultural and non-agricultural soil samples with the mean worldwide soils reveals that As, Co, Cu, Ni, V and Zn concentrations are higher than the mean worldwide values. Chromium in non-agricultural soils shows higher concentration than mean worldwide soils. The results of contamination factor (CF) for agricultural and non-agricultural soils reveal that As, Co, Ni, Zn and V have moderate and Cu has considerable contamination factor. The application of modified degree of contamination (mCd) indicates very low to low degrees of contamination in soil samples of Hashtgerd area. The enrichment factor shows that Cu, Zn, Pb and V in agricultural soils and Cr and Zn in non-agricultural soils are enriched compared to the average abundances of the background level. The principal component analysis (PCA) was used to assess the association of elements. The strong association of elements such as Co, Fe, Ni, and Cr in agricultural soils and Cu, V, Co, Fe, Co and Ni in non-agricultural soils suggests lithogenic control and pedological processes. Copper, vanadium and zinc in agricultural soils display a quasi-independent behavior within the groups that show geogenic and anthropogenic sources. The variable behaviors of Pb, and As probably reflect various sources of these elements. The overall results demonstrate that the soil contamination is not a significant threat in the area, but considering the increasing rate of industrialization, agricultural activity and urbanization development in Hashtgerd area, the soils would require more monitoring of trace elements contamination in future.

کلیدواژه ها:

Soil contamination ، Enrichment factor ، Principal component analysis ، Hashtgerd ، Iran