Department of Geography, University College of Wales, SY23 3DB, Aberystwyth, Dyfed, Wales.
Environ Geochem Health. 1988 Dec;10(3-4):84. doi: 10.1007/BF01758673.
Fresh snow and streamwater samples were collected on a daily basis throughout the winter and spring periods of 1984 and 1985 at a remote, upland catchment located within the Cairngorm Mountains, Scotland. Laboratory based partial-melt experiments undertaken on the snow samples demonstrated that both fractionation and preferential elution of trace-elements occur during melting, with the concentrations being 1.3 to 5.4 times greater than in the first 10 percent meltwater fractions than in the bulk snow (Abrahamset al., in press). At the onset of snowpack melting, the ions may be mobilised and redistributed within the snow profile, concentrating at depths from where they may be quickly removed during the early spring run-offf. The raised major- (Ca, Mg, Na, Cl, NO3 and SO4) and trace-element (Al, Cd, Cu, Fe, Mn and Pb) concentrations recorded in the streamwaters during the "acid-flush" episodes at the time of the first major periods of snow-melt, reflect both the meltwater composition and the influence of the catchment soils (Abrahamset al., submitted for publication). Differences in streamwater chemistry during the two periods of snow-melt which were studies can probably be related to the fact that snow-melt occurs under a variety of circumstances with significant variations in the sequence of precipitation, melt-events, temperature and snowcover occurring from year to year, even in the same catchment. The high concentrations of Al (up to 330 μg L(-1)) in the sireamwaters at the time of snow-melt, probably reflect leaching of this element from the soil. These elevated concentrations, in combination with other streamwater parameters, may prove toxic to aquatic life-forms at this time of year.
1984 年和 1985 年冬春两季，在苏格兰凯恩戈姆山脉偏远的高地集水区，每天采集新鲜积雪和溪流样本。对积雪样本进行的实验室局部融解实验表明，在融化过程中痕量元素发生分馏和优先洗脱，其浓度比前 10%融水高出 1.3 至 5.4 倍，比原雪高（Abraham 等人，待发表）。在积雪开始融化时，离子可能在雪层中移动和重新分布，在积雪深处浓缩，而在早春径流时迅速被清除。在第一次主要融雪期间，溪流水中记录到的主要（Ca、Mg、Na、Cl、NO3 和 SO4）和痕量元素（Al、Cd、Cu、Fe、Mn 和 Pb）浓度升高，反映了融水组成和集水区土壤的影响（Abraham 等人，已提交出版）。两次融雪期间溪流化学性质的差异可能与以下事实有关：融雪发生在各种情况下，降水、融雪事件、温度和积雪的顺序每年都有很大变化，即使在同一集水区也是如此。在融雪期间，溪流水中的 Al 浓度很高（高达 330μg/L），可能反映了该元素从土壤中的淋溶。这些高浓度与其他溪流水参数结合，可能对水生生物在每年的这个时候产生毒性。
