Increasing concentrations of dissolved organic carbon (DOC) have been identified in many freshwater systems over the last three decades. Studies have generally nominated atmospheric deposition as the key driver of this trend, with changes in climatic factors also contributing. However, there is still much uncertainty concerning net effects of these drivers on DOC concentrations and export dynamics. Changes in climate and climate mediated snowfall dynamics in northern latitudes have not been widely considered as causal factors of changes in long-term DOC trends, despite their disproportionate role in annual DOC export. We leveraged long-term datasets (1988–2013) from a first-order forested tributary of Lake Superior to understand causal factors of changes in DOC concentrations and exports from the watershed, by simultaneously evaluating atmospheric deposition, temperature, snowmelt timing, and runoff. We observed increases in DOC concentrations of approximately 0.14 mg C l −1...

中文翻译：

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气候，融雪动力学和大气沉积相互影响，以控制北方森林流中26年的溶解有机碳出口

在过去的三十年中，已经在许多淡水系统中发现了越来越高的溶解有机碳（DOC）浓度。研究通常将大气沉积定为这一趋势的主要驱动力，同时气候因素的变化也起了作用。但是，关于这些驱动因素对DOC浓度和出口动态的净影响仍然存在很多不确定性。尽管北纬地区气候和由气候介导的降雪动态的变化在年度DOC出口中所起的作用不成比例，但尚未被广泛认为是长期DOC趋势变化的原因。我们利用苏必利尔湖一级森林支流的长期数据集（1988-2013年）来了解DOC浓度变化和流域出口变化的因果关系，同时评估大气层沉积，温度，融雪时间和径流。我们观察到DOC浓度增加了约0.14 mg C l -1 ...