美舍河沉积物重金属地球化学特征及其环境意义

对海口市美舍河沉积物重金属进行分析,结果表明,沉积物重金属元素Cr、As和Cd的含量较高,并对美舍河沉积物重金属采用地质累积指数法和潜在生态风险评价法对其进行污染评价,研究结果表明,由地质累积指数可知：Cu、Zn和Pb元素属于无污染水平,其中Cu元素接近无污染到轻污染之间的水平;Ni元素属于轻污染水平;Cr和Cd元素属于轻污染到重污染之间的水平;As元素属于重污染水平;各重金属元素的污染程度顺序为：Zn〈Cu〈Pb〈Ni〈Cd〈As〈Cr，各重金属元素潜在生态危害系数顺序为：Zn〈Cu〈Pb〈Ni〈Cr〈As〈Cd，该研究区潜在生态风险指数肼平均值为45．28，属于轻微生态危害范围。

Geochemistry of Heavy Metals in Sediments in Meishe River and its Environmental Significance

The sediments of Meishe River were analyzed, the results showed that there exist higher content of heavy metals Cr, As and Cd in the sediment. A series of samples collected during the survey in sediment in Meishe River are analyzed to reveal the content distribution of heavy metals. And by use of Geoaccumulation and Hakanson ecological risk, the pollution of heavy metal in sediment were evaluated. The results showed that Cu, Zn and Pb elements are in pollution-free levels,among them Cu element is close to pollution-free to light pollution degree phase; Ni element is in light pollution level; Crand Cd elements are in light pollution to heavy pollution stage; As element is in heavy pollution level; sequentially degree ofcontamination of heavy metals is： Zn〈Pb〈Cu〈Ni〈Cd〈Cr〈As. Hakanson ecological risk evaluation shows that themain pollution factor of heavy metal is Cr and the sequence of factor index is Zn〈Cu〈Pb〈Ni〈Cd〈As〈Cr. And poten-tial ecological risk is Zn〈Cu〈Pb〈Ni〈Cr〈As〈Cd. The average potential ecological risk is 45.28, and it has slight potential ecological risk.