Evaluation of Heavy Metal Pollution in Dazhai Mellow-soil Field

In order to determine the pollution condition of heavy metal in Dazhai mellow-soil field, the content of Zn, Cr, Cu, Ni, Pb, As, Cd and Hg in this area were analyzed, the content of heavy metals in soils in Shanxi Soil Environment Quality Standard and the secondary standard of National Soil Environment Quality Standard were used as evaluation standard. Based on the single factor index method, the result showed that the content of 8 heavy metals in soil didn’t exceed the secondary standard of National Soil Environment Quality Standard, while the content of As, Hg, Ni, Pb exceeded Shanxi Soil Environment Quality Standard. The soil in the study areas reached high pollution of As, Hg, Pb, and the pollution index of Cu, Ni, Zn, Cd reached a high level. The potential ecological risk index order was Hg﹥Cd﹥As﹥Pb﹥Ni﹥Cu﹥Zn﹥Cr. The pollution level risk intensity was mild. The correlation analysis indicated that Cr, Ni, Zn, Cu, Cd and As were probably from the same source, while Hg and other heavy metals were not correlated. Heavy metals with high levels of pollution were closely related to agricultural fertilization, tourism, transportation, construction, daily life and production activities.