Variations in concentrations and bioavailability of heavy metals in rivers caused by water conservancy projects： Insights from water regulation of the Xiaolangdi Reservoir in the Yellow River  

作　　者：Jianwei Dong Xinghui Xia Zhining Zhang Zixuan Liu Xiaotian Zhang Husheng Li 

机构地区：[1]State Key Laboratory of Water Environment Simulation, Key Laboratory for Water and Sediment Sciences of Ministry of Education,School of Environment, Beijing Normal University, Beijing 100875, China [2]Center for Eco-Environmental Research, Nanjing Hydraulic Research Institute, Nanjing 210029, China [3]Beijing Center for Physical & Chemical Analysis, Beijing 100089, China [4]Hubei Provincial Center for Disease Control and Prevention, Wuhan 430079, China

出　　处：《Journal of Environmental Sciences》2018年第12期79-87,共9页环境科学学报（英文版）

基　　金：supported by the National Key R&D Program of China(No.2017YFA0605001);the National Natural Science Foundation of China(No.91547207);the Fund for Innovative Research Group of the National Natural Science Foundation of China(No.51721093)

摘　　要：Water regulation of the Xiaolangdi Reservoir of the Yellow River was chosen as a case to investigate variations in concentrations and bioavailability of heavy metals caused by water conservancy projects in rivers. Water and suspended sediment（SPS） samples were collected at downstream sampling sites along the river during this period. Concentrations and speciation of Zn, Cr, Cu, Ni, and Pb in water and SPS samples were analyzed, and their bioaccumulation was studied with Daphnia magna. This study indicated that the exchangeable and carbonatebound fractions of heavy metals in SPS decreased along the studied stretch, and the dissolved heavy metal concentrations increased along the river with 1.6–15 folds. This is because sediment resuspension increased along the river during water regulation, giving rise to the increase of heavy metal release from SPS. The dissolved Zn, Cu, Ni, and Pb concentrations were significantly positively correlated with SPS concentrations, and their increase along the river was greater than Cr. The body burdens of heavy metals in D. magna exposed into samples collected from the reservoir outlet were 1.3–3.0 times lower than those from downstream stations, suggesting that the heavy metal bioavailability increased during water regulation.This should be considered in the reservoir operation.Water regulation of the Xiaolangdi Reservoir of the Yellow River was chosen as a case to investigate variations in concentrations and bioavailability of heavy metals caused by water conservancy projects in rivers. Water and suspended sediment（SPS） samples were collected at downstream sampling sites along the river during this period. Concentrations and speciation of Zn, Cr, Cu, Ni, and Pb in water and SPS samples were analyzed, and their bioaccumulation was studied with Daphnia magna. This study indicated that the exchangeable and carbonatebound fractions of heavy metals in SPS decreased along the studied stretch, and the dissolved heavy metal concentrations increased along the river with 1.6–15 folds. This is because sediment resuspension increased along the river during water regulation, giving rise to the increase of heavy metal release from SPS. The dissolved Zn, Cu, Ni, and Pb concentrations were significantly positively correlated with SPS concentrations, and their increase along the river was greater than Cr. The body burdens of heavy metals in D. magna exposed into samples collected from the reservoir outlet were 1.3–3.0 times lower than those from downstream stations, suggesting that the heavy metal bioavailability increased during water regulation.This should be considered in the reservoir operation.

关 键 词：Heavy metals SPECIATION BIOACCUMULATION Suspended sediment DAM Water conservancy project 

分 类 号：TV697[水利工程—水利水电工程] X143[环境科学与工程—环境科学]