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.
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.
Environ Pollut. 2015 Nov;206:627-35. doi: 10.1016/j.envpol.2015.08.030. Epub 2015 Aug 28.
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.
为了探究三峡水库（TGR）内 Pb 的分布和来源，对取自一条干流和三条支流的沉积岩心进行了 Pb 浓度和同位素比值的测量。结果表明，沉积物中平均含有 43.54mg/kg 的 Pb，大约是地球化学背景浓度的 1.6 倍。干流沉积物的平均 Pb 浓度较高，但 (206)Pb/(207)Pb 略低，(207)Pb/(208)Pb 比值更具放射性，这与所有支流的情况不同。大部分 Pb 存在于可还原相中，而可交换和可氧化相中的 Pb 较少；因此，Fe-Mn 氧化物可能是人为 Pb 的主要汇。(206)Pb/(207)Pb 与 Pb 含量的双标图，以及 (206)Pb/(207)Pb 与 (207)Pb/(208)Pb 的双标图表明，煤燃烧是可交换、可还原和可氧化相中人为 Pb 的主要来源，而残余 Pb 主要来自自然源。在 TGR 下游地区，沉积物中 Pb 污染的煤消耗平均贡献率为 61.1%。
