摘要
对滇池126个采样点沉积物0～5 cm、5～10 cm和10-20 cm中Cu、Zn、Pb、Cr、Cd、Hg和As等7种金属的含量进行了分析测定,各金属含量测定结果均高于相应的参比值,表明滇池沉积物受到了不同程度的金属污染.各金属含量的水平分布很不均衡,Zn、Pb、Cd、Hg和As含量随沉积物深度的减小而增大,Cu和Cr含量则随沉积物深度减小而减小,表明滇池沉积物中Cu和Cr污染整体上出现了减缓的趋势,而Zn、Pb、Cd、Hg和As污染在不断加剧.用H(a)k(a)nson潜在生态风险指数对滇池沉积物金属污染的生态风险进行了分析,结果表明:滇池沉积物存在轻微的Cu、Zn、Pb、Cr和As污染生态风险,以及中等的Hg和Cd污染生态风险;全湖沉积物金属污染的平均生态风险指数RI值为205.03,属中等生态风险,但有快速加大的趋势.
Sediment samples were collected from 126 sites in the Dianchi Lake and tested for concentrations for copper, zinc, lead, cadmium, chromium, mercury, and arsenic in different layers (0 ~ 5 cm, 5 ~ 10 cm and 10 ~ 20 cm). It was found that concentrations of these metals in these samples were much higher than their respective references, indicating that the sediments of Dianchi were polluted to a varying degree. metal concentrations in the sediment did vary significantly with depth and sampling site. Concentrations of Zn, Pb, Cd, Hg, and As were generally high in the upper layer except for Cu and Cr, which might suggest that the pollution of Zn, Pb, Cd, Hg, and As is getting more and more severe, while the pollution of Cu and Cr is put under control. With the H?k?nson potential ecological risk index approach, ecological risk of the heavy metal pollution of the sediment in Dianchi Lake was analyzed. Results showed that the pollution of Cu, Zn, Pb, Cr, and As did not pose much ecological risk to the Dianchi Lake, while that of Cd and Hg did a moderate ecological risk. On the whole, the sediment in the Dianchi Lake was moderately polluted with heavy metals with a potential ecological risk index RI being 205.03, which was though moderate, but displays a trend of speeding up towards gravity.
出处
《土壤》
CAS
CSCD
北大核心
2007年第5期737-741,共5页
Soils
基金
中国科学院土壤与农业可持续发展国家重点项目(5022505)
国家自然科学基金项目(40471128)资助
关键词
沉积物
金属污染
生态风险指数
滇池
Sediment, Metal contamination, Ecological risk index, Dianchi Lake
