ABSTRACT

Major ion concentrations have greatly increased in many north temperate lakes and rivers over the last 3 decades as the result of deicing materials applied to their surrounding roads in winter. Salt-based deicing will likely continue or increase in the future, and preventative management strategies require an improved understanding of the flow pathways and timing of road salt and associated contaminant fluxes to downstream receiving waters. In the present study, we focused on the catchment of Saint-Charles River and its reservoir that provides drinking water for Quebec City, Canada. Major ion concentrations were measured in river waters and snowbanks along roads in subcatchments that differed in degree of urbanization, and during the same winter–spring period a mooring system was installed in the reservoir to continuously record conductivity. Large significant differences were found in the concentration and temporal behavior of ions between urbanized and forested watersheds. Snow sampled at 1 m from the roads had elevated concentrations of salts and other contaminants, and the highest solute concentrations in the reservoir and river waters occurred during snowmelt events. The results indicate that management of roadside snowmelt runoff during thawing events may largely prevent salt-associated contamination, and that winter snowmelt will require increasing attention as the climate continues to warm.

摘要

在过去的 3 年中，由于在周围道路上使用了除冰材料，因此在过去 3 年中，许多北温带湖泊和河流的主要离子浓度大大增加。基于盐的除冰可能会在未来继续或增加，预防性管理策略需要更好地了解道路盐的流动路径和时间以及相关的污染物通量到下游接收水域。在本研究中，我们关注的是圣查尔斯河的集水区及其为加拿大魁北克市提供饮用水的水库。在城市化程度不同的子汇水面积中，在河水和道路沿线的雪堤中测量了主要离子浓度，并且在同一冬春季节期间，在水库中安装了系泊系统以连续记录电导率。在城市化流域和森林流域之间离子的浓度和时间行为存在很大的显着差异。在距离道路 1 m 处采样的雪中盐和其他污染物的浓度升高，水库和河水中的溶质浓度最高发生在融雪事件期间。结果表明，解冻事件期间路边融雪径流的管理可以在很大程度上防止与盐相关的污染，并且随着气候持续变暖，冬季融雪将需要越来越多的关注。水库和河水中的溶质浓度最高发生在融雪事件期间。结果表明，解冻事件期间路边融雪径流的管理可以在很大程度上防止与盐相关的污染，并且随着气候持续变暖，冬季融雪将需要越来越多的关注。水库和河水中的溶质浓度最高发生在融雪事件期间。结果表明，解冻事件期间路边融雪径流的管理可以在很大程度上防止与盐相关的污染，并且随着气候持续变暖，冬季融雪将需要越来越多的关注。