Key Laboratory of Cenozoic Geology and Environment, Institute of Geology and Geophysics, Chinese Academy of Sciences, P.O. Box 9825, Beijing 100029, China.
Environ Sci Pollut Res Int. 2013 Jul;20(7):5013-27. doi: 10.1007/s11356-012-1379-x. Epub 2013 Jan 20.
This paper presents the results of wet precipitation chemistry from September 2009 to August 2010 at a high-altitude forest site in the southeastern Tibetan Plateau (TP). The alkaline wet precipitation, with pH ranging from 6.25 to 9.27, was attributed to the neutralization of dust in the atmosphere. Wet deposition levels of major ions and trace elements were generally comparable with other alpine and remote sites around the world. However, the apparently greater contents/fluxes of trace elements (V, Co, Ni, Cu, Zn, and Cd), compared to those in central and southern TP and pristine sites of the world, reflected potential anthropogenic disturbances. The almost equal mole concentrations and perfect linear relationships of Na(+) and Cl(-) suggested significant sea-salts sources, and was confirmed by calculating diverse sources. Crust mineral dust was responsible for a minor fraction of the chemical components (less than 15%) except Al and Fe, while most species (without Na(+), Cl(-), Mg(2+), Al, and Fe) arose mainly from anthropogenic activities. High values of as-K(+) (anthropogenic sources potassium), as-SO4(2-), and as-NO3(-) observed in winter and spring demonstrated the great effects of biomass burning and fossil fuel combustion in these seasons, which coincided with haze layer outburst in South Asia. Atmospheric circulation exerted significant influences on the chemical components in wet deposition. Marine air masses mainly originating from the Bay of Bengal provided a large number of sea salts to the chemical composition, while trace elements during summer monsoon seasons were greatly affected by industrial emissions from South Asia. The flux of wet deposition was 1.12 kg N ha(-1) year(-1) for NH4(+)-N and 0.29 kg N ha(-1) year(-1) for NO3(-)-N. The total atmospheric deposition of N was estimated to be 6.41 kg N ha(-1) year(-1), implying potential impacts on the alpine ecosystem in this region.
本文介绍了 2009 年 9 月至 2010 年 8 月在青藏高原东南部一个高海拔森林地区采集的湿沉降化学数据。由于大气中尘埃的中和作用，该地区的碱性湿沉降 pH 值在 6.25 至 9.27 之间。主要离子和微量元素的湿沉降水平与世界其他高山和偏远地区相当。然而，与青藏高原中部和南部以及世界原始地区相比，微量元素（V、Co、Ni、Cu、Zn 和 Cd）的含量/通量明显更高，反映出潜在的人为干扰。Na(+)和 Cl(-)的摩尔浓度几乎相等，线性关系完美，表明存在大量的海盐来源，这一点通过多种来源的计算得到了证实。除了 Al 和 Fe 之外，地壳矿物尘埃仅占化学物质的一小部分（小于 15%），而大多数物质（不包括 Na(+)、Cl(-)、Mg(2+)、Al 和 Fe）主要来自人为活动。冬季和春季观测到的高 as-K(+)（人为来源钾）、as-SO4(2-)和 as-NO3(-)值表明，在这些季节生物质燃烧和化石燃料燃烧的影响巨大，这与南亚的雾霾爆发相吻合。大气环流对湿沉降中的化学物质有显著影响。主要源自孟加拉湾的海洋气团为化学物质组成提供了大量的海盐，而夏季季风季节的微量元素则受到南亚工业排放的极大影响。NH4(+)-N 的湿沉降通量为 1.12kgNha(-1)year(-1)，NO3(-)-N 的湿沉降通量为 0.29kgNha(-1)year(-1)。大气氮的总沉降量估计为 6.41kgNha(-1)year(-1)，这意味着该地区的高山生态系统可能会受到影响。
