青藏高原南部枪勇冰川雪冰中痕量元素的组成特征及其环境意义

为了认识青藏高原南部雪冰中痕量元素的组成特征、背景含量水平以及人为污染的可能影响,利用高分辨电感耦合等离子体质谱仪首次对2009年4月19日采自枪勇冰川一个40 cm 雪坑中 Al、 Fe、 Ba、 Cd、Co、Cr、Cu、Li、Ni、Zn、Pb、Sb、Sr、U 和 V 共15个痕量元素的浓度进行了测试和研究.分析表明,不同痕量元素之间浓度变化很大,从 Cd 的0.004 ng/g 变化到 Fe 的8628 ng/g;同一痕量元素的浓度变化范围也较大,最大值/最小值从13(Cd)变化到94(Sr).研究表明,不同痕量元素记录反映了人类活动与自然活动的不同影响.对痕量元素地壳富集系数分析表明,岩石和土壤粉尘是 Ba、Fe、Sr、Co、Cr、V 和 U 的主要来源;而人为污染是枪勇冰川中 Pb、Zn、Cu、Li、Ni、Cd 和 Sb 的一个重要来源.对比研究表明,无论是以粉尘源为主要来源的痕量元素,还是以人为源为主要来源的痕量元素,它们的浓度明显高于中亚有关地区冰川中痕量元素的浓度,更远远地高于格陵兰和南极雪冰中的相应浓度,揭示了该地区大气中痕量元素受到粉尘和人为源污染物带来的显著影响

The composition characteristics and environmental significance of trace elements in the firn core of Qiangyong glacier,Southern Qinghai-Tibetan Plateau

In order to know the composition characteristics,the background content,and the possible influence of human activities on trace elements in snow and ice in southern Qinghai-Tibetan Plateau,the concentrations of 15 trace elements,e.g.,Fe,Ba,Cd,Co,Cr,Cu,Li,Ni,Zn,Pb,Sb,Sr,U and V in a 70 cm snow pit which was collected on April 19,2009 from Qiangyong glacier were determined using inductively coupled plasma sector field mass spectrometry.It was shown that large changes of concentrations exist for different trace elements ranging from 0.004 ng/g(Cd) to 8628 ng/g(Fe).The concentrations also change in a large range for the same element shown by the value of Max/Min varies from 13(Cd) to 94(Sr).Different trace element reflects different influence from human activity and natural activities.Based on crustal enrichment factors(EFc) it is shown that rock and soil dusts were the main sources for Ba,Fe,Sr,Co,Cr,V and U,while human activities were important source for Pb,Zn,Cu,Li,Ni,Cd and Sb in the Qiangyong glacier.Compared with other areas,concentrations of trace elements either from soil dusts or from human activities are higher than some other glaciers in central Asia,and exceed largely the concentrations in Greenland and Antarctic.All these indicated that trace elements in the atmosphere of Qiangyong has influenced from both dusts and human activities.