海口城市土壤重金属污染特征与生态风险评估  

Pollution characteristics and ecological risk assessment of heavy metals in Haikou urban soils

作　　者：何玉生[1] 

机构地区：[1]海南省地质调查院,海口570206

出　　处：《生态学杂志》2014年第2期421-428,共8页Chinese Journal of Ecology

基　　金：中国地质调查局多目标生态地球化学调查项目(1212010511215)资助

摘　　要：对海口城市土壤重金属含量、空间分布特征与赋存形态进行了研究,并评估了其生态风险。结果表明,海口城市土壤重金属Hg、As、Cd、Cu、Cr、Ni、Pb、Zn的平均含量分别为0.073、3.82、0.25、26.7、92.4、52.5、29.1和84.1 mg·kg-1。与海口土壤背景值相比,海口城市土壤明显富集重金属Hg、As、Cd、Cu、Cr、Ni、Pb和Zn,受到一定程度重金属污染。Cr、Ni、Cu、Cd和Zn元素主要在郊区富集,Pb主要在路边绿化带中富集,Hg主要在生活区富集。海口城市土壤中Zn、As、Cr、Cu和Ni以残渣态为主,Hg主要以强有机态和残渣态存在,Pb主要以铁锰氧化态和残渣态存在,而Cd则主要以生物可利用态为主。生态风险评价结果显示,海口城市土壤重金属综合生态风险属于微弱水平,但Cd和Hg污染应引起重视。The concentration, distribution, and speciation of heavy metals in urban soils of Haik- ou City were investigated. The mean concentrations of heavy metals Hg, As, Cd, Cu, Cr, Ni, Pb and Zn were 0. 073,3.82, 0.25,26.7, 92.4, 52.5,29.1 and 84.1 mg ·kg^-1 , respective- ly. In comparison with the background values, the enrichments of Hg, As, Cd, Cu, Cr, Ni, Pb and Zn in the soils of Haikou City were obvious, indicating a certain degree of heavy metal pollu- tion. Cr, Ni, Cu, Cd and Zn were enriched in suburban areas, while Pb was enriched in road- side green belts and Hg was enriched in residential areas. Zn, As, Cr, Cu and Ni in the soils of Haikou were predominantly in residual fraction. Hg was mainly associated with strong organic- bound and residual fractions, while Pb was mainly presented as iron and/or manganese oxide- bound fractions. On the contrary, Cd existed mainly in bio-available fractions. The results of multiple-metals ecological risk assessment indicate that the heavy metal pollution in the soils of Haikon is at a relatively low level. However, Cd and Hg pollution deserves much more attention.

关 键 词：城市土壤 重金属 分布特征 赋存形态 

分 类 号：X53[环境科学与工程—环境工程]