Speciation Analysis and Pollution Assessment of Heavy Metals in Farmland Soil of a Typical Mining Area: A Case Study of Dachang Tin Polymetallic Ore, Guangxi

作者：Jiali Zhang, Yinghong Liu, Songtao Hong, Meilan Wen, Chaojie Zheng, Panfeng Liu · 发表于：Applied Sciences · 年份：2023 · DOI：10.3390/app13020708 · 被引用次数：15 · 研究领域：Heavy metals in environment、Heavy Metal Exposure and Toxicity、Mining and Resource Management

To explore the distribution characteristics and degree of pollution of heavy metals in the farmland soil around the Dachang tin polymetallic mining area in Guangxi, a total of 140 soil samples were collected around the mining area in this study. The total amount and various forms of seven heavy metals (Cu, Pb, Cd, Cr, Zn, As, and Ni) were analyzed by inductively coupled plasma mass spectrometry, and the improved continuous extraction method of heavy metal speciation analysis in the soil, the potential ecological risk index (RI), the and Nemerow evaluation index (PN) were used to evaluate pollution characteristics of the soil and the bioavailability of heavy metals. Corresponding remediation suggestions were given according to the pollution degree. The results show that the whole soil in the study area is acidic, reducing, and the content of organic matter is low. The average content of heavy metal elements is higher than the background value of Guangxi, among which Cd, Pb, and As exceed the control value and are the main elements of pollution. The speciation analysis of heavy metals in soil shows that Cd is dominated by the ion exchange form; Cu is mainly residual and in a humic acid combined form; and the rest of the elements are mainly in residual form. Among the seven heavy metals, Cd has the strongest mobility, biological toxicity, and ecological risk, followed by As, Ni, and Zn. The overall pollution level of the soil in the study area is heavily polluted (PN = 39.6), wh...