地积累指数法在土壤重金属污染评价中的应用

应用地积累指数对广州5个郊区的土壤重金属污染情况进行了评价研究．从广东省土壤重金属背景值计算的地积累指数结果来看，广州郊区土壤中Hg和CA都达到中度污染，zn为轻度-中度污染，Pb，As，Cu，Cr，Ni都不存在污染．从8种元素的分级频率来看，Hg的污染频率最大，达到89．8％；其次是Cd和Zn，分别是78．2％和54．6％；其余5种元素污染频率的大小顺序为Pb，As，Cu，Cr，Ni；Hg出现了5．9％的极严重污染．广州5个郊区的污染元索和元素的污染程度存在着明显的差别，Q型聚类分析将海珠区、芳村区、天河区和黄埔区聚为一类，为较高程度污染区；而把白云区单列一类，为低污染区；同时，整个广州的污染情况与白云区聚为同一类．

Application of Index of Geoaccumulation (Igeo) to Pollution Evaluation of Heavy Metals in Soil

Pollution of heavy metals in soil in Guangzhou suburbs is(evaluated) on the basis of the index of geoaccumulation.The results show that the pollution of Hg and Cd in the soil of the suburbs of Guangzhou City is classified as moderate degree,and that of Zn as between slight and moderate degrees,and five other metals of no pollution according to the results of I_(geo) based on the background value of heavy metals in the soil of Guangdong Province.The pollution frequency of Hg is 89.8%,the highest among the 8 metals,and those of Cd and Zn are 78.2% and 54.6% respectively,next to the highest,and the pollution degree of the other five metals can be put in this order:Pb,As,Cu,Cr,Ni,of which Pb is the highest and Ni is the lowest.Hg causes very serious pollution,for it reaches 5.9%.There are quite different polluting metals and polluting degrees in the 5 suburbs of Guangzhou City.Haizhu,Fangcun,Tianhe and Huangpu are grouped into the same degree,which are the heavily polluted areas.Baiyun is a less heavily polluted area,the same as Guangzhou City.