摘要
为探究长江中下游底泥重金属污染状况,对长江中下游主干河流及湖泊的27个断面的底泥进行采集并测定镉、铅、铬、铜、锌、砷和汞的浓度。运用潜在生态风险指数法对重金属污染进行评价,并采用相关分析和主成分分析对重金属的污染来源进行分析。结果表明:Hg、Cd、Pb、Cr、Cu、Zn和As的含量分别为0.010～0.55 mg/kg、0.016～0.17 mg/kg、13.04～110.03 mg/kg、42.03～121.03 mg/kg、21.70～75.10 mg/kg、48.01～750.01 mg/kg和6.03～82.95 mg/kg。重金属浓度较高的地方位于较为发达的城市(武汉和南京)、采矿业发达的地区(安庆、大通和芜湖)、港口城市(城陵矶)以及湖泊(鄱阳湖和东洞庭湖)。由潜在生态风险评价可知,7种重金属污染程度的大小顺序为:Hg>As> Pb>Cd>Cu>Cr>Zn。相关分析和主成分分析结果表明Pb、Cd、Zn、Cu、Hg和Cr主要来源于煤炭燃烧、农业活动及生活污水,As主要来源于采矿业和航运业。长江中下游及湖泊底泥所有点位的Pb、Cu、Cr、Zn和Cd均处于轻微潜在生态风险状态,As和Hg在部分点位具有较高潜在生态风险。结合所有重金属元素来说,长江中下游以及湖泊底泥的潜在生态风险水平较低。
Aiming at understanding pollution situation of the middle and lower reaches of the Yangtze River, twenty seven sediment samples are collected from the river and lakes of the middle and lower reaches of the Yangtze River.Contents of Cd, Pb,Cr, Cu,Zn, As and Hg are tested.The pollution of heavy metals is evaluated by potential risk assessment. Correlation analysis(CA) and principle component analysis(PCA) are areapplied to identify the possible pollution sources of the seven heavy metals. The result shows that contents of Hg, Cd, Pb, Cr, Cu, Zn and As are 0.010~0.55 mg·kg-1,0.016~0.17 mg·kg-1, 13.04~110.03 mg·kg-1, 42.03~121.03 mg·kg-1, 21.70~75.10 mg·kg-1, 45.01~750.01 mg·kg-1and 6.03~82.95 mg·kg-1.Contents of heavy metals are higher in developed cities(Wuhan and Nanjing), mining areas(Anqing,Datong and Wuhu),port city(Chenglingji) or lakes(Poyang lake and East Dongting lake).The pollution of the seven heavy metals are ordered by Hg>Cd>As>Cu>Pb>Cr>Zn according to potential risk assessment index. Correlation analysis and principal component analysis shows that the pollution sources of Pb, Cd, Zn, Cu, Hg and Cr mainly originate from coal combustion, agricultural activities and domestic sewage.The pollution sourcse of As are mainly mining and shipping industry.Contents of Cd,Pb, Cu, Cr and Zn all have the possibility of causing lower ecological risk.While As and Hg show high ecological risk possibilities at some sites. Considering all heavy metals, sediment of river and lakes of the middle and lower reaches of the Yangtze River are in lower potential ecological risk.
作者
易雨君
王文君
宋劼
YI Yujun;WANG Wenjun;SONG Jie(Ministry of Education Key Laboratory of Water and Substrate Science, School of Environment, Beijing Normal University,Beijing 100875, China)
出处
《水利水电技术》
北大核心
2019年第2期1-7,共7页
Water Resources and Hydropower Engineering
基金
国家重点研发计划(2016YFC0502209)
国家自然科学基金(51722901
51439001)
关键词
底泥
重金属
潜在生态风险评价
污染源
sediment
heavy metal
potential ecological risk assessment
pollution source
