US Geological Survey, Denver, Colorado, United States.
Environ Sci Technol. 2012 Sep 4;46(17):9324-32. doi: 10.1021/es3020056. Epub 2012 Aug 17.
A unique 30-year streamwater chemistry data set from a mineralized alpine watershed with naturally acidic, metal-rich water displays dissolved concentrations of Zn and other metals of ecological concern increasing by 100-400% (400-2000 μg/L) during low-flow months, when metal concentrations are highest. SO(4) and other major ions show similar increases. A lack of natural or anthropogenic land disturbances in the watershed during the study period suggests that climate change is the underlying cause. Local mean annual and mean summer air temperatures have increased at a rate of 0.2-1.2 °C/decade since the 1980s. Other climatic and hydrologic indices, including stream discharge during low-flow months, do not display statistically significant trends. Consideration of potential specific causal mechanisms driven by rising temperatures suggests that melting of permafrost and falling water tables (from decreased recharge) are probable explanations for the increasing concentrations. The prospect of future widespread increases in dissolved solutes from mineralized watersheds is concerning given likely negative impacts on downstream ecosystems and water resources, and complications created for the establishment of attainable remediation objectives at mine sites.
从一个矿化高山流域获得的独特的 30 年地表水化学数据集中，自然酸性、富含金属的水显示溶解浓度的 Zn 和其他生态关注的金属在低流量月份增加了 100-400%（400-2000μg/L），此时金属浓度最高。SO(4) 和其他主要离子也显示出类似的增加。在研究期间，流域内没有自然或人为的土地干扰，这表明气候变化是潜在的原因。自 20 世纪 80 年代以来，当地的年平均和夏季平均气温以每年 0.2-1.2°C 的速度上升。其他气候和水文指标，包括低流量月份的流量，没有显示出统计学上的显著趋势。考虑到由气温上升驱动的潜在具体因果机制，推测可能的解释是永冻层融化和地下水位下降（由于补给减少）导致浓度增加。考虑到未来从矿化流域中溶解溶质的广泛增加可能对下游生态系统和水资源产生负面影响，以及对矿山修复目标的可实现性造成的复杂性，这是令人担忧的。
