阳宗海沉积物重金属污染评价及来源解析

Pollution Evaluation and Source Identification of Heavy Metals in Sediments of Yangzonghai

对沉积物中重金属进行污染评价及来源分析有助于为重金属污染治理提供决策依据。该研究以阳宗海不同湖岸湖滨湿地沉积物为研究对象,运用沉积物富集系数法和内梅罗指数法评价沉积物中9种重金属污染程度,并运用聚类分析和因子分析法对重金属污染来源进行识别。结果表明:(1)阳宗海湖滨湿地沉积物中重金属在不同湖岸呈现不同分布特征,As、Cd、Cr、Zn、Mn在东部含量较高,Co、Cu、Ni最高值出现在北部;Pb最高值出现在南部;(2)在研究区域Cd属于重度污染,As、Zn、Cu、Cr、Ni、Pb和Co均属于中等污染水平,且EF值均大于1,表明该研究区的重金属污染物除了来自地壳和自然风化过程,还受到于人类活动、工业生产等外源污染影响;(3)阳宗海不同湖岸重金属Mn和Cd累积效应最为显著,在东部湖滨湿地As和Cu的累积效应也较显著,其余重金属在不同湖滨湿地表现出不同程度的污染累积;(4)因子分析可将9种重金属归为第一主成分(Zn、Cu、Cd、Ni、Pb、Co、Mn),贡献率为72.16%,为工业因子,第二主成分(As、Cd)为能源因子,通过聚类表明,该研究区域在污染程度上可分为3大类,主要受西南季风、铝厂、火电厂等影响。基于该研究结果,在今后环境治理时应该加强污染源控制,保护阳宗海生态环境。

Based on the measurements of heavy metals in the sediments collected from 12 sampling points from Yangzong-hai,Pollution degrees of 9 kinds of heavy metals of the sediments in the moat were analyzed using Nemero index and sedi-ment enrichment factor, and sources of the heavy metals indentifed using cluster and factor analyses. Results show that:(1)Yangzonghai Lake wetland sediments of heavy metals in different lakes shore show different distribution, As, Cd, Cr, Zn, Mn content is higher in the east; Co, Cu, Ni highest value appears in the north; Pb peak appears in the south;(2)In the study area Cd belongs to heavily polluted, As, Zn, Cu, Cr, Ni, Pb and Co are belong to moderate pollution level, and the EF values were greater than 1, indicating that heavy metal contaminants in the study area apart from the earth's crust and the natural weather-ing processes, but also by human activities, industrial production extrinsic source pollution;(3)Different lake area the heavy metals of Mn and Cd cumulative effect is the most significant, the accumulation effect of As and Cu in the eastern lakeside area is also more significant, remaining heavy metals in different lakeside wetland exhibit different degrees of pollution accu-mulation in Yangzonghai;(4)The factor analysis of nine kinds of heavy metals can be classified as the first principal compo-nent(Zn, Cu, Cd, Ni, Pb, Co, Mn), the contribution rate is 72.16% and as the industrial factor, the second principal component(As, Cd) as the energy factor, through clustering results showed that the degree of pollution in the study area can be divid-ed into three categories, mainly affected by the southwest monsoon, aluminum plant and thermal power plant, etc. Based on the results of the study, the environmental governance should strengthen pollution source control in the future, protectingYangzonghai ecological environment.