多元统计法解析县域外源性土壤重金属—以尤溪县为例

Multivariate Statistical Methods to Resolve County Exogenous Heavy Metals in Soil—A Case Study in Youxi County

摘要: 本文选择尤溪县联合乡和梅仙镇为关键研究区，采用多元统计和地质统计分析，研究区土壤重金属的主要来源及与土地利用、成土母质之间的关系。结果表明：As、Cd、Cr、Cu、Cd、Hg、Pb、Zn的平均值均高于背景值，尤其是Cd、Pb的含量分别为背景值的264、12.25倍，土壤中重金属累积较为明显。7种元素可被辩识出4个主成分I_n：I₁(Cu、Cd、Pb、Zn)为自然源因子、I₂(Cd、Cr、Zn)为工农业及交通源因子、I₃(As、Cu、Hg)为农业源因子和I₄(Pb、Zn、Cu)为工业源因子。其中Pb、Zn在I₁和I₄上均有较大载荷，受地质背景和人类活动的共同控制。

Abstract: This paper chose Lianhe Town and Meixian Town as the key research areas in Youxi County. Mul-tivariate statistical and geostatistical analysis were used to reveal the major source of heavy metals, and the relationship between heavy metals and land use, heavy metals and soil parent material. The results showed that: the mean value of As, Cd, Cr, Cu, Cd, Hg, Pb, Zn was higher than the background value; in particular content of Cd, Pb was 264, 12.25 times the background value re-spectively, and the accumulation of heavy metals in soil was more significant. Seven kinds of ele-ments can be identified as four main components I_n: I₁ (Cu, Cd, Pb, Zn) is natural source factors; I₂ (Cd, Cr, Zn) is industrial and agricultural source and transport factors; I₃ (As, Cu, Hg) is agricultural source factors; and I₄ (Pb, Zn) is industrial source factors. Pb and Zn have a larger load on I₁ and I₄, controlled by geological background and human activity jointly.