北极阿拉斯加春季积雪中汞的时空分布及其来源分析

开展北极雪冰中汞分布特征及其来源的探究，不仅可以丰富冰冻圈汞生物地球化学循环的认识，而且对评估北极环境中汞的潜在暴露风险具有现实意义。在2017年4月至5月对美国阿拉斯加的积雪进行大范围样品采集，探讨了该区域积雪中汞的空间分布特征及其成因、汞的沉降后过程以及潜在来源分析。研究表明：积雪中汞的空间分布受大气汞亏损事件（AMDEs）及人为源的共同影响，毗邻北冰洋海岸（如巴罗）积雪中总汞（THg）浓度较高，接近人为源的山地表层雪中THg浓度较高。巴罗雪坑中THg浓度随深度增加呈下降趋势。积雪中主要阴阳离子与THg的相关性分析表明，阿拉斯加积雪中THg的空间分布可能主要受北冰洋海盐气溶胶以及人类活动的影响。

Spatiotemporal distribution and potential sources of snow mercury in Arctic Alaska during the spring season

Investigation on the distribution， post-deposition process and potential sources of mercury （Hg） in Arctic snow can not only enhance our understanding of Hg biogeochemical cycling in the cryosphere， but it is also imperative for assessing the potential exposure risk of Hg to Arctic environment. Extensive sampling of surface snow was conducted in Alaska between April and May in 2017. Spatial pattern of snow Hg distribution was discussed to explore the post-deposition process of snow Hg and its potential sources. Measurements of total mercury （THg） showed that the spatial pattern of snow Hg was governed by both atmospheric mercury depletion events （AMDEs） and nearby anthropogenic sources. The higher THg concentration was generally observed near the Arctic Ocean （such as Barrow）， and the regions in which were located near the anthropogenic sources. THg concentration showed a downward trend with depth in the Barrow snowpacks. By using correlation analysis among concentrations of major anions and cations， and THg， we concluded that THg in the Alaska snow might be mainly influenced by Arctic sea salt aerosol and anthropogenic emissions.