摘要
对太湖流域某市农业活动区具代表性的14个监测点的土壤(0～10、20～30和50～60 cm)进行采样分析,利用多元统计和地统计学方法,研究了该地区Cd、Pb、Cr和Mn等重金属的空间分布特征及其主要来源.结果表明,各采样点和各层土壤之间重金属的含量变化较大,变异系数为39.05%～243.52%.各层土壤中w(Cd)和w(Pb)以及底层土壤中w(Cr)均超过土壤背景值,尤其是w(Cd),表层、中层和底层分别为19.92、17.41和19.97 mg/kg,远高于背景值.地统计学分析表明,各层土壤中w(Cd)、w(Pb)以及表层土壤中w(Cr)的高值区主要分布在研究区北部,而中层和底层土壤中w(Cr)的高值区主要分布在研究区南部.w(Mn)受自然因素的影响较大,分布较为均匀.表层、中层和底层土壤中w(Cr)和w(Mn)的相关系数分别为0.715(P<0.01)、0.632(P<0.05)和0.602(P<0.05),w(Pb)与w(Cd)的相关系数分别为0.842(P<0.01)、0.590(P<0.05)和0.874(P<0.01).主成分分析表明,研究区耕地土壤中w(Mn)主要受地球化学的影响,Cd、Pb和Cr的污染主要来源于工厂所排放的废气、废水,机动车尾气,以及农业活动施入的化肥、农药.
The spatial distribution and main sources of heavy metals in Taihu Lake basin were studied based on analysis of soil samples from fourteen representative monitoring sites（0-10, 20-30, 50-60 cm） with GIS and statistical multi-analysis. The results showed that the concentrations of heavy metals varied greatly at different sampling sites as well as among different layers. The coefficient of variation was from 39.05% to 243.52%. The concentrations of Cd and Pb in each layer as well as Cr at the bottom exceeded the soil background value in Jiangsu, especially the concentrations of Cd at the surface（ 19.92 mg/kg）, middle（ 17.41 mg/kg） and bottom（ 19.97 mg/kg）. Geostatistical analysis showed that the high values of Cd and Pb in each layer and Cr on the surface were mainly distributed in the northern part of the study area. The high value of Cr in the middle and at the bottom was mainly distributed in the southern part of the study area. Mn was evenly distributed, probably due to natural factors. The coefficients of correlation between Cr and Mn were 0. 715 （P 〈 0. 01 ）,0. 632 （ P 〈 0. 05 ） and 0. 602 （ P 〈 0. 05 ） respectively, while the coefficients of correlation between Pb and Cd were 0. 842 （ P 〈 0. 01 ）, 0. 590 （ P 〈 0. 05 ） and 0. 874 （ P 〈 0. O1 ） respectively in each soil layer. Principal component analysis indicated that Mn was mainly influenced by the geochemistry in the study area, while Cd, Pb and Cr in the soil samples were mainly derived from waste gas, water from factories, vehicle emissions and pesticides and fertilizer from agricultural activities.
出处
《环境科学研究》
EI
CAS
CSCD
北大核心
2012年第12期1319-1327,共9页
Research of Environmental Sciences
基金
国家环境保护公益性行业科研专项(201109009)
国家重点基础研究发展(973)计划项目(2008CB418205)
关键词
太湖流域
重金属
多元地统计
空间分布
来源
Taihu Lake basin
heavy metals
statistical multianalysis
spatial distribution
sources
