Bengbu higher education mega center was selected as target area to study the accumulation of heavy metals based on the field investigation, sampling, indoor test and statistical analysis. The results indicated that the mean concentrations of heavy metals (Pb, Zn, Cr, Cu, Cd and Ni) in surface soils were 23.04, 60.69, 37.79, 24.06, 1.15 and 18.67 mg/kg respectively. Cd and Cu exceeded the soil background values of Anhui province by 11.86 and1.18 times, whereas the others were within their background values. Compared with Grade II criterion of national environmental quality standards for soils in China, Cd concentrations in all samples were obviously more than the corresponding limits, suggesting that the accumulation of Cd observed was serious in the study area. Assessment on ecological risk revealed that Cd showed the potential ecological risk at high and very high level with the proportion of 29.4 and 70.6, respectively. The strongest ecological risk occurred in Longhu Chuntian business street, which is a complex area with booming commerce, high population density and heavy traffic. Results of multivariate analyses indicated that Cr and Ni mainly originated from geological weathering, Pb, Zn and Cu came from vehicle traffic pollution, Cd was dominantly related to agricultural and industrial activities.
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