| Abstract:
Due to their toxicity and persistence in the environment heavy metals are among the most significant soil contaminants. Therefore, it is essential to investigate the distribution of heavy metals for controlling contamination of soil and maintaining the quality of the environment. This study aimed to assess the level of contamination and mapping the spatial patterns of heavy metals i. e. chromium, nickel, copper, lead and zinc in topsoil of Mahshahr in 2016. For this purpose, 51 surface soil samples (0-20 cm) were systematically collected and their metal concentrations were measured by XRF. Also, soil EC, pH, lime and soil texture were determined. Pollution index (PI), and Nemerow integrated pollution index (NIPI) were used to determine the soil contamination level. Concentration Distribution maps of heavy metals were prepared using the interpolation method in geographic information system (GIS). Principal component analysis (PCA) was performed to investigate the relationship between metals. The results indicated the highest PI of chrome and nickel which are in high contamination level. Many urban soils in Mahshahr have been contaminated with a sort of low or moderate levels of lead, zinc and copper. NIPI showed that all parts are in high pollution levels. The results of principal component analysis indicated that copper, lead, and zinc were placed under the same category revealed to be of man-made and common origins. Chromium and nickel have been placed in a separate category and the quantity of pollution index of these metals with high variable coefficient was determined to be of anthropogenic origin.
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