中文摘要：

分析了红枫湖表层沉积物中有机质及10种重金属元素的含量,并应用平均富集因子（AEFs）对其污染状况进行了评价.结果表明,红枫湖表层沉积物的重金属按污染水平可分为3类：轻度污染（AEFs〈2）的Cd、Pb、Zn、Cr,As、Fe和Mn,中度污染（AEFs=2～3）的Cu,严重污染（AEFs〉3）的Ni和Hg.同时,通过主成分分析（PCA）法对影响湖泊沉积物中重金属分布的因素进行了分析,并在进行统计分析前,用Al对重金属元素含量进行了校正,以消除沉积物粒度对重金属分布的影响.分析结果表明,前3个主成分的贡献率分别为48.7%、20.5%、12.6%,所占比例总和大于80%,即这3个主成分基本能够代表原污染因素的大部分信息.结合湖泊特点及周边点源污染情况分析发现,红枫湖表层沉积物中重金属污染主要有3个可能来源：工业排污及Fe和Mn的影响;有机质的影响;早期岩石的风化及侵蚀（背景值）.PCA聚类分析结果表明,本研究所调查的14个站位在污染程度上可分为4类,其结果反应出红枫湖沉积物中部分重金属、部分站位污染程度相对较重的特点,同时也进一步说明了工业排污是沉积物中重金属污染的主要来源.

英文摘要：

Concentrations of heavy metals and organic matter in sediments from Hongfeng Lake were determined and the average enrichment factors（AEFs） were used to evaluate the degree of heavy metal accumulation.The results showed that heavy metal contamination in the lake could be divided into three groups： negligible to low contamination（AEFs 2）,which is the case for Cd,Pb,Zn,Cr,As,Fe and Mn;moderate contamination（AEF = 2 ～ 3）,which is the case for Cu;and certain to severe contamination（AEFs 3）,which is the case for Ni and Hg.Principal component analysis（PCA） was also applied to estimate the sources of heavy metal contamination.Prior to the statistical analysis,Al was used to normalize the concentrations of heavy metals,which eliminates the effect of granularity of the sediments on the distribution of heavy metals.The results demonstrated that the principal components from the first to the third accounted for 48.7%,20.5%,12.6% of the total variance,respectively,implicating that discharge of industrial wastewater and effect of Fe and Mn,organic matter,erosion of rocks（background value） were possible sources of this contamination.In addition,hierarchical cluster analysis（HCA） indicated that the 14 stations could be divided into four groups according to the degree of pollution.The results from this analysis reflect that pollution of some heavy metals is relatively heavy in sediments from Hongfeng Lake and that industrial discharge is the main source of that contamination.