The role of Mineral Salts Company in pollution of Mighan playa sediments with heavy metals by contamination indices and multivariate analysis methods, Arak, Iran

Heavy metal concentrations were investigated for ۳۰ sediments collected from different regions of Mighan playa/lake. The means of Cr, Cu, Ni, Pb, Zn and Cd in sediments of playa/lake were much lower than the soil guideline values of Iran and background values of region (BVR). However, the maximum concentrations of Cr, Cu, Ni, Pb, Zn and Cd were higher than BVR. Only ۷% of Cr, Cu, Zn, ۲۷% of Ni, ۱۴% of Pb and ۳۸% of Cd concentration exceeded the BVR. The heavy metal Cr, Zn, Ni and Cd are the most important metals in different land use. About ۱۱% of the samples in the lake land use contain Cr, Ni, Pb and Zn has concentration higher than BVR. The concentration of Cu and Pb in ۳۳% and ۶۷% samples is exceeded the BVR in Tail of Mineral Salts Company. The spatial distribution patterns of Cr, Cu, Ni, Pb, Zn and Cd were generally similar and increase from Mighan playa/lake to the Arak city and mainly affected by anthropogenic sources. Among the six types of land use, the concentrations of Cr, Ni, Zn and Cd in the range land and wastewater sludge were significantly higher than those in the other land use (p <۰.۰۵). In factor analysis, Cr, Ni, Zn in factor۱, Cd in factor۲, Pb, Zn in factor۳ were originated from the municipal sewage, industrial plants activities and Arak urban traffic.

کلیدواژه ها:

heavy metal pollution ، Soil and sediment contamination ، Anthropogenic sources ، Statistical methods ، Mighan playa/lake