State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Donggang West Rd. 320, Lanzhou, 730000, China.
Himalayan Environment Research Institute (HERI), Kathmandu, Nepal.
Environ Sci Pollut Res Int. 2021 Oct;28(37):51530-51543. doi: 10.1007/s11356-021-14334-2. Epub 2021 May 13.
In this work, samples of surface snow, surface ice, snow pit and meltwater from the Laohugou Glacier No. 12 on the northern edge of Tibetan Plateau (TP) were collected during the summer of 2015. The average concentration of Hg in surface snow/ice was 22.41 ng L, while the percentage of dissolved mercury (Hg) was observed to be around 26%. An altitudinal magnification of Hg was not observed for surface snow; however, in contrast, a significant positive magnification of Hg with altitude was observed in the surface ice. A higher concentration of Hg corresponded with the dust layer of the snow pit. It was observed that about 42% of Hg was lost from the surface snow when the glacier was exposed to sunlight within the first 24 h indicating some Hg was emitted back to the atmosphere while some were percolated downwards. The result from the principal component analysis (PCA) showed that the sources of Hg in Laohugou Glacier No. 12 were from crustal and biomass burning. Finally, it was estimated that total export of Hg from the outlet river of Laohugou glacier No. 12 in the year 2015 was about 1439.46 g yr with yield of 22.77 μg m yr. This study provides valuable insights for understanding the behavior of Hg in the glacier of the northern Tibetan Plateau.
本研究于 2015 年夏季在青藏高原北缘老沟 12 号冰川采集了表层雪、表面冰、雪坑和融水样本。表层雪/冰中 Hg 的平均浓度为 22.41ng/L，而溶解态汞（Hg）的比例约为 26%。表层雪中没有观察到 Hg 的海拔放大效应；然而，相反，在表面冰中，Hg 随着海拔的升高呈显著的正放大效应。Hg 浓度与雪坑的粉尘层相对应。研究发现，当冰川在最初 24 小时内暴露在阳光下时，表层雪中约有 42%的 Hg 流失，这表明部分 Hg 被排放回大气中，而部分则向下渗透。主成分分析（PCA）的结果表明，老沟 12 号冰川 Hg 的来源来自地壳和生物质燃烧。最后，据估计，2015 年老沟 12 号冰川出口河流中 Hg 的总排放量约为 1439.46g·yr，产率为 22.77μg·m·yr。本研究为了解青藏高原北部冰川中 Hg 的行为提供了有价值的见解。
