汾河水库周边土壤重金属含量与空间分布

基于95个表层土壤样品重金属实测含量,运用多元统计和地统计相结合的方法,对汾河水库周边土壤重金属含量的分布特征和来源进行分析.结果表明,研究区土壤重金属Cr、Cu、Ni、Pb、Zn的平均含量分别为38.45、19.09、24.02、11.98、55.01 mg.kg-1,均没有超过国家土壤环境质量一级标准和山西省土壤背景值,但各元素均有部分样品含量超过山西省土壤背景值,其中Pb、Cr和Cu的超标率较为显著,分别为28%、14%和13%.相关分析和因子分析结果显示,各元素超标部分的来源可分为三类,Cu、Ni和Zn为一类,Cr和Pb分别单独为一类.分析各重金属空间分布图发现,第一类元素的超标部分主要来源于城镇区域内的日常生活和生产活动,Cr和Pb的超标部分则分别主要来源于农业生产活动和交通运输等.Cr和Pb元素的高值区分别位于汾河水库的上游和下游区域.

Concentrations of Soil Heavy Metals and Their Spatial Distribution in the Surrounding Area of Fenhe Reservoir

Based on the concentrations of heavy metals from 95 topsoil samples, the spatial distribution characteristics and sources of the heavy metals in soil of the surrounding area of Fenhe Reservoir were analyzed with a method combining multivariate statistics and geo-statistics. The results showed that the average concentrations of the Cr, Cu, Ni, Pb, and Zn in soil of study area were 38.45, 19.09, 24.02, 11.98 and 55.01 mg·kg^-1, respectively, and all were lower than the first class standard of the national soil environment and the background values of soil in Shanxi Province. For all heavy metals, there were some samples with concentrations higher than the background values of soil in Shanxi Province, especially for Pb, Cr, and Cu, exceeding by 28%, 14%, and 13%, respectively. The results of correlation analysis and factor analysis showed that the sources of the excess of these heavy metals could be divided into three categories, Cu, Ni and Zn as one class, Cr and Pb as the other two classes. Spatial structure analysis showed the excess of Cu, Ni, and Zn came mainly from daily life and production activities, and the excess of Cr and Pb came mainly from agricultural activities and transportation.