title: Heavy Metal Pollution, Fractionation, and Potential Ecological Risks in Sediments from Lake Chaohu (Eastern China) and the Surrounding Rivers.
abstract: Heavy metal (Cr, Ni, Cu, Zn, Cd, and Pb) pollution, fractionation, and ecological risks in the sediments of Lake Chaohu (Eastern China), its eleven inflowing rivers and its only outflowing river were studied. An improved BCR (proposed by the European Community Bureau of Reference) sequential extraction procedure was applied to fractionate heavy metals within sediments, a geoaccumulation index was used to assess the extent of heavy metal pollution, and a risk assessment code was applied to evaluate potential ecological risks. Heavy metals in the Shuangqiao and Nanfei Rivers were generally higher than the other studied sites. Of the three Lake Chaohu sites, the highest concentrations were identified in western Chaohu. Heavy metal pollution and ecological risks in the lake's only outflowing river were similar to those in the eastern region of the lake, to which the river is connected. Heavy metal concentrations occurred in the following order: Cd > Zn > Cu > Pb ≈ Ni ≈ Cr. Cr, Ni, and Cu made up the largest proportion of the residual fraction, while Cd was the most prominent metal in the exchangeable and carbonate-included fraction. Cd posed the greatest potential ecological risk; the heavy metals generally posed risks in the following order: Cd > Zn > Cu > Ni > Pb > Cr.
authors.affiliation: State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, China. leizhang@niglas.ac.cn.
authors.forename: Lei
authors.initials: L
authors.lastname: Zhang
authors.affiliation: Department of Environmental Science, China Pharmaceutical University, Nanjing 211198, China. liaoqianjiahua@163.com.
authors.forename: Qianjiahua
authors.initials: Q
authors.lastname: Liao
authors.affiliation: College of Hydrology and Water Resource, Hohai University, Nanjing 210098, China. sgshao@live.cn.
authors.forename: Shiguang
authors.initials: S
authors.lastname: Shao
authors.affiliation: Department of Environmental Science, China Pharmaceutical University, Nanjing 211198, China. zhangnan920705@163.com.
authors.forename: Nan
authors.initials: N
authors.lastname: Zhang
authors.affiliation: State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, China. qsshen@niglas.ac.cn.
authors.forename: Qiushi
authors.initials: Q
authors.lastname: Shen
authors.affiliation: State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, China. jerrylaw0326@gmail.com.
authors.forename: Cheng
authors.initials: C
authors.lastname: Liu
mesh_terms: D002681:China; D004463:Ecology; D004784:Environmental Monitoring; D004787:Environmental Pollution / Q000032:analysis*; D019015:Geologic Sediments / Q000032:analysis*; D060106:Lakes; D019216:Metals, Heavy / Q000032:analysis*; D018570:Risk Assessment; D045483:Rivers
chemical_list: D019216:Metals, Heavy
keywords: Lake Chaohu; ecological risk; heavy metal; sediment