The characteristic of Pb isotopic compositions in different chemical fractions in sediments from Three Gorges Reservoir, China

Lanfang Han; Bo Gao; Xin Wei; Li Gao; Dongyu Xu; Ke Sun

doi:10.1016/j.envpol.2015.08.030

The characteristic of Pb isotopic compositions in different chemical fractions in sediments from Three Gorges Reservoir, China

Environ Pollut. 2015 Nov:206:627-35. doi: 10.1016/j.envpol.2015.08.030. Epub 2015 Aug 28.

Authors

Lanfang Han¹, Bo Gao², Xin Wei³, Li Gao¹, Dongyu Xu⁴, Ke Sun⁵

Affiliations

¹ 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.
² 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.
³ State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing, 100875, China.
⁴ 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.
⁵ State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing, 100875, China. Electronic address: sunke@bnu.edu.cn.

PMID: 26319507
DOI: 10.1016/j.envpol.2015.08.030

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.

Keywords: Lead contamination; Pb isotopic ratios; Sediments; Sequential extraction; Three Gorges Reservoir.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

China
Environmental Monitoring / methods*
Geologic Sediments / chemistry*
Isotopes / analysis
Lead / analysis*
Lead Radioisotopes / analysis*
Water Pollutants, Chemical / analysis*

Substances

Isotopes
Lead Radioisotopes
Water Pollutants, Chemical
Lead