太湖主要入湖河口表层沉积物重金属分布特征及风险评价  

Distribution and Risk Assessment of Heavy Metals in the Surface Estuarine Sediments of Main Inflow Rivers in Taihu Lake

作　　者：闫兴成 杨晓薇[1] 黄烯茜 董傑靖 王明玥[1,2] 韩睿明[1,2] 王国祥[1,2] YAN Xingcheng;YANG Xiaowei;HUANG Xiqian;DONG Jiejing;WANG Mingyue;WANG Guoxiang;HAN Ruiming(School of Environment, Nanjing Normal University, Nanjing 210097, China;Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application//Jiangsu Key Laboratory of Environmental Change and Ecological Construction//Jiangsu Engineering Laboratory of Water and Soil Eco-remediation, Nanjing 210023, China)

机构地区：[1]南京师范大学环境学院,江苏南京210097 [2]江苏省地理信息资源开发与利用协同创新中心//江苏省环境演变与生态建设重点实验室//江苏省水土环境生态修复工程实验室,江苏南京210023

出　　处：《生态环境学报》2016年第9期1515-1521,共7页Ecology and Environmental Sciences

基　　金：国家水体污染控制与治理重大专项(2012ZX07101-008-02);江苏省太湖水环境综合治理科研项目(JSZC-G2014-212);国家自然科学基金项目(41403064);江苏省教育厅基础研究计划(自然科学基金)青年基金项目(BK20140922);江苏省教育厅高校自然科学研究面上项目(14KJB610007)

摘　　要：为揭示太湖主要入湖河口表层沉积物重金属分布特征及其生态风险,采集太湖西岸和北岸12条主要入湖河口表层沉积物样品,对沉积物中5种重金属元素(Cu、Zn、Ni、Pb、Cd)的含量及空间分布特征进行了分析,并利用地累积指数法和潜在生态风险指数法分别研究了表层沉积物重金属的累积程度及生态风险。结果表明,调查的12条入湖河流河口表层沉积物均受到不同程度的重金属污染,Cu、Zn、Ni、Pb、Cd的平均质量分数分别为63.04、173.11、56.71、37.05、2.23 mg?kg^(-1)。各重金属在空间分布上具有差异性,总体表现为大港河(DGH)、乌溪港(WXG)庙渎港(MDG)、大浦港(DPG)、陈东港(CDG)、官渎港(GDG)、洪巷港(HXG)、社渎港(SDG)河口表层沉积物以重金属Cd污染为主,而沙塘港(STG)、太滆运河(TG)、直湖港(ZHG)、梁溪河(LXH)河口表层沉积物表现为Cu、Zn、Ni、Pb的复合污染。地累积指数法评价表明,各入湖河流河口表层沉积物重金属的污染程度表现为Cd>Cu>Zn>Ni>Pb。潜在风险指数(riE)表明各重金属的潜在生态风险表现为Cd>Cu>Ni>Pb>Zn,主要污染物为Cd。其中庙渎港(MDG)和社渎港(SDG)处于严重风险状态,大港河(DGH)、乌溪港(WXG)、大浦港(DPG)、官渎港(GDG)、洪巷港(HXG)处于重度风险状态,陈东港(CDG)、太滆运河(TG)处于中度风险状态,其余点位生态风险较低。研究表明,西岸入湖河流表层沉积物重金属潜在生态风险等级高于北岸,但北岸入湖河流河口表层沉积物中Cu、Zn、Ni、Pb的累积也应当得到重视。To reveal the distributive characteristics and ecological risk of heavy metals in the estuarine sediment of the inflow riversin Taihu Lake, surface sediments were collected from the estuaries of 12 inflow rivers located in the western and northern shores ofTaihu Lake. Concentrations of five heavy metals (Cu, Zn, Ni, Pb, Cd) were quantified for the sampled sediments, and the spatialdistribution characteristics were analyzed. The pollution extent and potential ecological risk of each heavy metal were evaluatedbased on the geo-accumulation index (Igeo) and the potential ecological risk factor ( rEi ) respectively. The results indicated that all ofthe 12 main inflow rivers had been confronted with heavy metal contamination to certain extents in the surface estuarine sediments.The average concentrations of Cu, Zn, Ni, Pb, Cd were 63.04, 173.11, 56.71, 37.05, 2.23 mg?kg-1 respectively. Spatial heterogeneitywas found in the distribution of different heavy metals: the estuaries of inflow rivers Daganghe (DGH), Wuxigang (WXG),Miaodugang (MDG), Dapugang (DPG), Chendonggang (CDG), Guandugang (GDG), Hongxianggang (HXG) and Shedugang (SDG)were mainly polluted by Cd, while the estuaries of Shatanggang (STG), Taigeyunhe (TG), Zhihugang (ZHG) and Liangxihe (LXH)were polluted by a combination of Cu, Zn, Ni and Pb. According to geo-accumulation index (Igeo), the pollution extent of heavymetals in surface sediment followed the order as: Cd>Cu>Zn>Ni>Pb. According to ecological risk factor ( rEi ), the potentialecological risk of heavy metals in surface sediment followed the order as: Cd>Cu >Ni>Pb>Zn, and Cd was the major pollutant forrisk. Among the 12 inflow rivers’ estuaries, MDG and SDG were of serious ecological risk, DGH, WXG, DPG, GDG and HXG wereof severe ecological risk, CDG and TG were of moderate ecological risk, STG, ZHG, LXH were of low ecological risk. It wasdemonstrated that the levels of potential ecological risk of heavy metals in the estuaries of inflow rivers located between DGH andSDG were higher than that betwe

关 键 词：太湖 入湖河口 表层沉积物 重金属 风险评价 

分 类 号：X52[环境科学与工程—环境工程]