[Source Apportionment and Transport Pathway Analysis of Heavy Metal Pollution in Soils Around a Coal-fired Power...

In order to explore the influence of heavy metals in pollutant emissions from a coal-fired power plant on the surrounding soil environment, the content characteristics of heavy metals Pb, Mn, Zn, Cr, Ni, Cu, As, Co, Hg, and Cd in the soil around a coal-fired power plant in Baoji City were collected and analyzed. Combined with the PMF model and spatial interpolation technology, the key pollution sources and their contribution characteristics in the region are qualitatively and quantitatively identified, and the optimal parameter geographic detector technology is further used to integrate multi-dimensional environmental parameters such as PM_2.5 mass concentration and night light data to identify the pollution driving factors and pollution pathways. The optimal research grid scale is determined through grid analysis. The results showed that: ① The contents of Pb, Zn, Cu, As, Hg, and Cd in the soil around the coal-fired power plant were 9.68, 1.12, 1.02, 1.42, 13, and 4 times as the background values, respectively, and compared with the risk screening values, the Cd and Pb elements exceeded the standard, indicating that there was some pollution in the area. ② The main sources of heavy metals in the soil in the study area were dust reduction sources (38.00%), natural and agricultural sources (26.89%), and industrial and agricultural sources (35.10%). ③ PM_2.5, night light data, precipitation, and population density had strong explanatory power on the spatial distribution of each pollution source, and the main pollution pathways of dust reduction sources, natural and agricultural sources, and industrial and agricultural sources were wind transmission, irrigation water transportation, and transportation, respectively. ④ The optimal research grid scale of a coal-fired power plant in Baoji City was 150 m grid cells. The results show that in the soil around a coal-fired power plant in Baoji City, priority needs to be given to the prevention and control of Cd and Pb pollution, and source control for wind power should mainly be implemented, which can provide a research framework for soil treatment in similar areas.