Mercury (Hg) export from glacierized watersheds is poorly understood, with very few studies worldwide on Hg concentration and speciation in glacier snow, ice, and meltwater, and on Hg fluxes to downstream freshwater and coastal ecosystems. In addition to bedrock-derived geogenic Hg, glaciers may be releasing legacy accumulations of natural and anthropogenically-sourced Hg trapped in glacier ice melt each summer season. Our prior work showed that a glacierized stream in southeast Alaska had the highest reported flux of inorganic mercury of all known non-mining impacted streams, highlighting the strong ability of glaciers to mobilize the trace metal. Here we present data on Hg concentrations, speciation, partitioning, and fluxes from two more glacierized watersheds (Herbert and Mendenhall Rivers), and we compare them to an adjacent non-glacierized, forested-wetland stream (Peterson Creek). Results show that the glacierized streams carried Hg largely in the particulate form, whereas the forested-wetland stream carried it largely in the filtered fraction, at 20 fold higher concentration than in the glacierized streams, and with a higher percent of Hg in its methylated form. Yet, considering the higher water and sediment yields (as mass per watershed area per year) of the glacierized streams during the summer melt season, the yield of total Hg (unfiltered) from the Mendenhall glacier was approximately 80 times higher than from the Herbert glacier and 50 times higher than in Peterson Creek and presents the highest watershed yields of total Hg and methyl-Hg reported in the literature to date. Incongruous yields out of the two glacierized streams can likely be explained by differences in underlying bedrock geology. Based on the sediments entrained in Mendenhall meltwater, the late Paleozoic to Paleocene metasedimentary and volcanic rocks being eroded in the terminal 3 km of the Mendenhall are elevated above mean crustal concentrations by at least 4–17 fold. Differences in speciation between the glacierized and non-glacierized streams are likely accounted for by glacial and watershed geochemical conditions that variably promote Hg methylation.

人们对冰川流域的汞出口知之甚少，全世界对冰川雪，冰和融化水中的汞浓度和形态，以及向下游淡水和沿海生态系统的汞通量的研究很少。除了基岩成因的汞外，每个夏季，冰川还可能释放残留在冰川冰融化中的自然和人为来源的汞。我们的先前工作表明，阿拉斯加东南部的冰川流在所有已知的非采矿影响流中具有最高的无机汞通量，这凸显了冰川动员痕量金属的强大能力。在这里，我们提供了来自另外两个冰川化流域（赫伯特河和门登霍尔河）的汞浓度，形态，分配和通量的数据，并将它们与相邻的非冰川化流域进行了比较，森林湿地流（彼得森溪）。结果表明，冰川流中的汞主要以颗粒形式携带，而森林湿地流中的汞主要以过滤后的馏分形式存在，其浓度比冰川流中的汞高20倍，且甲基化形式的汞含量更高。然而，考虑到夏季融化季节冰川化河流的水和沉积物产量（以每年每个集水区的质量计）较高，Mendenhall冰川的总Hg（未过滤）的产量约为Herbert冰川的80倍。比彼得森溪高50倍，是迄今为止文献中报道的总Hg和甲基Hg分水岭产量最高的地区。两种冰川化流中的产量不一致可能是由于潜在的基岩地质学差异造成的。根据Mendenhall融水中夹带的沉积物，在Mendenhall终端3 km处被侵蚀的晚古生代至古新世的沉积和火山岩比平均地壳浓度高出至少4-17倍。冰川化流域和非冰川化流域的形态差异可能是由于冰川和流域地球化学条件的变化而引起的，而这些地球化学条件会不同程度地促进汞的甲基化。