湘江沉积物铅污染计算

湘江是我国重金属污染最严重的河流之一。本次工作利用多接收同位素质谱（MC-ICP-Ms）技术，分析湘江入湖沉积物的Pb同位素组成。结果表明，湘江三角洲沉积物存在严重的pb污染。Pb同位素源区示踪分析表明，河床沉积物的铅为花岗岩自然Pb、Pb-zn矿床的矿石铅和燃煤烟尘铅的三元混合铅，其中花岗岩占20％，华南煤所占比例为10％，方铅矿所占比例为70％。；湖盆沉积物中的铅则以Pb-Zn矿床的矿石铅和燃煤烟尘铅构成的人为源Pb为主．受上游岩石风化影响较小。

Lead Isotopes As A Tracer OF PB Origin OF The Sediments OF The Xiangjiang Reiver

Each Pb isotope ratios coincides with its source,therefore,application of Pb isotope ratios is becoming an important means in identifying Pb sources.Hunan province is famous for her abundant ore mineral resources, thus The Xiangjiang River is one of the rivers which were contaminated by heavy metals most seriously. The present study analyzed the Pb composition of the sediments of the Xiangjiang River and major pollutant source using MC-ICP-MS techniques. The results show that the river sediments has extremely pollution ,but more less in the lake sediments. Pb isotopic geochemistry of the sediments display that metal Pb in sediments was a mixture of two endmembers： Pb from the regional carbonates of the watershed and Pb from the nonferrous metal mines of the upriver areas. The major sources of the heavy metals of the inlet sediments were from mineral processing of the nonferrous metal ores distributed in the upriver＇ area. Anthropogenic contribution of Pb to the sediments was65% -80%. Therefore, the protection of heavy metal contamination for the region should be stressed on various industrial activities of mineral application of nonferrous metal ores such as mines and factories.