中文摘要：

通过对长江口北支CY孔47个样品的重金属Cr、Cu、Pb和Zn的数据分析,采用单因子污染参数法和Hakanson潜在生态风险指数法,评价了长江口北支CY孔沉积物的质量状况。定量确定了长江口北支沉积物重金属的潜在生态风险程度、主要污染因子和潜在生态风险因子。从环境演变角度探讨了长江口北支沉积物重金属总的潜在生态风险和单个重金属元素的潜在生态风险的演变趋势。结果表明,长江口北支沉积物重金属含量与沉积环境演变关系密切,不同的气候条件下,具有不同的沉积环境特点,形成不同的沉积物环境状况。就气候演变而言,从层1至层7,气候依次为热暖潮湿→暖热湿润→温和略干→温暖湿润→温暖稍温→温而略干→温暖湿润,对应的重金属含量变化依次按低→高→减少→增多→减少→减少→显著增大的规律变化。

英文摘要：

The contents of typical pollutants,such as Cr,Cu,Pb and Zn,in the sediments of the Hole CY in the North Branch of the Changjiang River Estuary were analysed,by using single factor analysis for pollution parameter and Hakanson′s potential ecological risk assessment as tools.Testing data are from the 47 samples collected from the Hole CY.The authors carried out the quantitative assessment of heavy metal pollution,the major factors of environment pollution and potential ecological risks.Results suggest that the heavy metal pollution is closely related with enviromental factors depending upon climate conditions,and sedimentary environment.Taking climatic changes as an example,we can see that,from layer to layer 7,the climate changed from hot-warm and moist → warm and moist → temperate and a little dry → warm and moist → warm and a little moist → temperate and a little dry → warm and moist.Accordingly,the quantity of heavy metals changes from high→decrease →increase → decrease → decrease → evidently increase.