中国淮北平原典型矿区农田表层土壤重金属污染特征与源解析

Characteristics and Source Analysis of Heavy Metal Pollution in the Surface Soil of Farmland in Typical Mining Areas of Huaibei Plain, China

摘要: 为探究采煤活动影响区农田土壤重金属的含量特征与来源，选取宿县矿区周边农田表层土壤重金属(Cr、Mn、Ni、Cu、Zn、As、Cd和Pb)作为研究对象。利用数理统计、多元统计分析和地累积指数法，分析研究区农田表层土壤重金属的含量特征、污染水平和潜在污染来源。结果表明：1) 在研究区采集的土壤样品中Mn、Zn、Pb、Cu、Cd、As的含量高于安徽省土壤背景值；2) 相关性分析研究表明：As与Cr之间存在较为明显的正相关性关系，推测两者可能来自同一污染源；Cd和Ni、Cu正相关性明显，Cd的来源特征可能与Ni、Cu相似；Zn与Pb、Mn之间正相关性明显，表明Zn的来源与Pb、Mn的来源相近。其他4种重金属元素Pb、Mn、Ni、Cu由于其元素之间相关性存在一定差异，推测这5种重金属元素的来源不同。3) 主成分分析结果表明：研究区农田表层土壤中的重金属元素受采矿活动、交通因素、农业面源污染及自然因素影响。4) 地累积指数结果表明：Zn、Pb、Ni、Mn、Cr呈无污染状态；As、Cd和Cu呈轻度污染状态。

Abstract: In order to explore the content characteristics and sources of heavy metals in farmland soil in the area affected by coal mining activities, heavy metals (Cr, Mn, Ni, Cu, Zn, As, Cd and Pb) in the surface soil of farmland around The Mining Area of Suxian County were selected as the research objects. Mathematical statistics, multivariate statistical analysis and land accumulation index method were used to analyze the content characteristics, pollution levels and potential pollution sources of heavy metals in the surface soil of farmland in the study area. The results showed that: 1) The contents of Mn, Zn, Pb, Cu, Cd and As in the soil samples collected in the study area were higher than the soil background values in Anhui Province. 2) Correlation analysis studies have shown that there is a relatively obvious positive correlation between As and Cr, and it is speculated that the two may come from the same pollution source; Cd is positively correlated with Ni and Cu, and the source characteristics of Cd may be similar to Ni and Cu; The positive correlation between Zn, Pb and Mn is obvious, indicating that the source of Zn is similar to the source of Pb and Mn. The other four heavy metal elements Pb, Mn, Ni, Cu have certain differences in the correlation between their elements, and it is speculated that the sources of these five heavy metal elements are different. 3) Principal component analysis results show that the heavy metal elements in the surface soil of the farmland in the study area are affected by mining activities, traffic factors, agricultural non-point source pollution and natural factors. 4) The results of the ground accumulation index show that Zn, Pb, Ni, Mn and Cr are in a state of no pollution; As, Cd, and Cu are mildly contaminated.