青藏高原天然水体中As变化初步研究

Preliminary Study on the Arsenic Concentration in Surface Water on the Tibetan Plateau

根据测得的青藏高原部分天然地表水体 (包括河水、湖水等 )中As的含量 ,初步分析了青藏高原部分地区天然地表水中As的空间分布规律 .研究发现 ,青藏高原不同区域河水中As的浓度存在显著的空间变化 ,尤其是狮泉河流域河水中异常高的As含量 .这种空间差异可能是由地区土壤与岩石中As含量的差异造成的 ,而那曲河水中较高的As可能反映了人类活动的影响 .湖水中As的含量高于河水 ,最高可高达 12 0 0 μg·L-1以上 .内陆湖湖水中高的As含量可能与水的蒸发浓缩有关 。

Based on the measured results for some natural surface water (including river water, lake water and so on) on the Tibetan Plateau, the spatial distribution of As concentration is discussed in this paper. An obvious spatial variation of As in surface water is found. There is an extremely high As concentration in the Shiquanhe Basin, west of the Plateau. Its spatial distribution is dependent on the geochemistry in soil and rock. Higher concentration in the river water of Nagqu Prefecture may be resulted from human activity, such as mining. As compared with river water, lake water has a higher As concentration, with the measured maximum of {1 200} %μ%g5L+{-1}. The higher As concentration in lake water (especially in inner lake water) can be attributed to evaporation condensation, together with high As input within river water.