title: The characteristic of Pb isotopic compositions in different chemical fractions in sediments from Three Gorges Reservoir, China.
abstract: To explore the distribution and sources of Pb within the Three Gorges Reservoir (TGR), Pb concentrations and isotope ratios were measured in sediment cores collected from one mainstream and three tributaries. The results showed that sediments contained an average of 43.54 mg kg(-1) of Pb, roughly 1.6 times higher than the geochemical background concentration. Mainstream sediments showed higher average Pb concentrations but slightly less (206)Pb/(207)Pb and more radiogenic (207)Pb/(208)Pb ratios than all tributaries. Most Pb occurred in reducible phases, with much less in exchangeable and oxidizable fractions; thus, Fe-Mn oxides may be the major sink of anthropogenic Pb. Bi-plots of (206)Pb/(207)Pb versus Pb content, and of (206)Pb/(207)Pb versus (207)Pb/(208)Pb, indicated that coal combustion was the predominant anthropogenic Pb source for exchangeable, reducible, and oxidizable fractions, while residual Pb mainly occurred naturally. The average percentage of coal consumption contribution was 61.1% for the Pb contamination in sediments in the lower reaches in the TGR region.
authors: State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin, China Institute of Water Resources and Hydropower Research, Beijing, 100038, China; State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing, 100875, China.
authors: Lanfang
authors: L
authors: Han
authors: State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin, China Institute of Water Resources and Hydropower Research, Beijing, 100038, China; Department of Water Environment, China Institute of Water Resources and Hydropower Research, Beijing, 100038, China. Electronic address: gaosky34@hotmail.com.
authors: Bo
authors: B
authors: Gao
authors: State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing, 100875, China.
authors: Xin
authors: X
authors: Wei
authors: State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin, China Institute of Water Resources and Hydropower Research, Beijing, 100038, China; State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing, 100875, China.
authors: Li
authors: L
authors: Gao
authors: State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin, China Institute of Water Resources and Hydropower Research, Beijing, 100038, China; Department of Water Environment, China Institute of Water Resources and Hydropower Research, Beijing, 100038, China.
authors: Dongyu
authors: D
authors: Xu
authors: State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing, 100875, China. Electronic address: sunke@bnu.edu.cn.
authors: Ke
authors: K
authors: Sun
mesh_terms: D002681:China; D004784:Environmental Monitoring / Q000379:methods*; D019015:Geologic Sediments / Q000737:chemistry*; D007554:Isotopes / Q000032:analysis; D007854:Lead / Q000032:analysis*; D007856:Lead Radioisotopes / Q000032:analysis*; D014874:Water Pollutants, Chemical / Q000032:analysis*
chemical_list: D007554:Isotopes; D007856:Lead Radioisotopes; D014874:Water Pollutants, Chemical; D007854:Lead
keywords: Lead contamination; Pb isotopic ratios; Sediments; Sequential extraction; Three Gorges Reservoir