台州市典型电子垃圾拆解场地周边农田土壤重金属污染特征和来源解析

为分析台州市电子垃圾拆解场地周边农田土壤中重金属污染特征和来源贡献，在2021年3月采集研究区230个表层（0~20cm）农田土壤，测定了样品中9种重金属（Cr、Co、Ni、Cu、Zn、As、Cd、Hg和Pb）元素含量。通过污染负荷指数（PLI）和潜在生态风险指数（RI）分析重金属的生态风险，并利用地统计、多变量统计和...

Pollution characteristics and source analysis of heavy metals in farmland soils around the e-waste dismantling sites in Taizhou City, China

In order to analyze the pollution characteristics and source contributions of heavy metals in farmland soils around the e-waste dismantling sites in Taizhou City, 230 surface (0~20 cm) farmland soils in the study area were collected in March 2021. The contents of heavy metals (Cr, Co, Ni, Cu, Zn, As, Cd, Hg, and Pb) in these soils were determined. The ecological risks of the heavy metals were analyzed using the pollution load index (PLI) and potential ecological risk index (RI). Moreover, the sources of the soil heavy metals in this area were analyzed using the combination of geostatistics, multivariate statistics and PMF modelling. The results showed that the Cd pollution levels of farmland soils around the study area were the highest, the median exceeded the risk screening values for soil contamination of agricultural land, and the exceeding standard rate reached 75.65%. In addition, the exceeding standard rates of Cr and Cu were relatively high, 27.39% and 42.61% respectively. The comprehensive pollution load index indicated that 16.96% and 7.39% of the samples constituted moderate or serious pollution, respectively. Nevertheless, the potential risk indices (55.22% and 34.78%) of the samples were considered moderate and above severe risk, respectively. The comprehensive results of geostatistics, multivariate statistics and PMF modelling showed that the sources of nine heavy metals in these soil samples could be divided into four categories:Co, Cr, and Ni mainly come from natural sources; As mainly comes from agricultural sources; Zn, Cu, Cd, and Pb mainly come from metal smelting sources, concentrating in the farmland soils around historical e-waste dismantling sites; and Hg mainly comes from coal and industrial sources.