Assessment of Heavy Metals Enrichment and Sources in Different Functional Areas of Sixian City

To investigate soil heavy metal pollution in different functional areas of Sixian City, 48 soil samples were collected in residential, industrial, green, and commercial areas. The concentrations of V, Cr, Zn, Cu, Pb, and as were determined by the geoaccumulation index method and the enrichment factor method, and their pollution levels were evaluated. At the same time, the possible sources of heavy metals were identified by the factor analysis method. The results showed that except for V, the concentrations of the other five heavy metals were higher than the soil background values of Anhui Province. The geoaccumulation indexes revealed that V, Cr, and as were free of pollution, while some sampling sites of Zn, Pb, and Cu were slightly polluted in different functional areas. Heavy metal pollution in different functional areas ranked as commercial area>industrial area>residential area>green area. Given the enrichment factor, V was pollution-free, and as was mildly enriched in all functional areas. Cr was slightly enriched except for the green areas; Zn and Cu were mild to moderately enrichment; Pb was mild to moderately enriched except for the green areas and the pollution in commercial areas was serious. The factor analysis showed that the large contribution rate of Pb and Zn in the first factor may be related to traffic; the second factor (Cr, Cu, and as) possibly come from electronics, metallurgy burning, and machinery manufacturing, and the third factor was a natural process. It can be seen that Zn, Cu, and Pb are the main soil pollution elements in the functional areas of Sixian City.