Source analysis and risk evaluation of heavy metals in soils of typical old industrial bases in Xuzhou City

In this study, a typical old industrial base was selected for the investigation of heavy metal pollution in the surrounding soil to lay a solid foundation for the exploration of ecological restoration model of old industrial bases. In this study, 21 soil samples around a power plant in Xuzhou City were collected, and the contents of five heavy metals, Cr, Cd, Cu, Ni and Pb, were measured by ICP-MS. The results showed that Cd, Cu and Pb had accumulated in the soil around the old industrial base, and Cd and Pb exceeded the standard at some points. The correlation analysis and PMF model were used to analyze the sources of soil heavy metals, and the results showed that the soil heavy metals might be influenced by industrial sources, transportation sources, atmospheric deposition sources and natural sources. Pollution risk evaluation of soil heavy metals was carried out using single-factor pollution index method, Nemero pollution index method and potential ecological risk index method, and the results showed that Cd pollution was more serious and the ecological risk level was higher. This proves that the old industrial base has adversely affected the surrounding environment and requires pollution prevention and control.