Role of terrestrial carbon and base cations in the recovery of damaged aquatic systems

清洁的水和多样化的水生生物群落是如此依赖分水岭的过程，以至于它们可以被认为是北方盾牌生态区健康森林的“产品”。陆地分水岭的碳输入是稀释湖生产力的关键决定因素，颗粒碳和溶解碳(DOC)对接收湖泊和溪流的食物网有很大贡献。森林土壤中的盐基阳离子也会影响大量的水生过程，包括引入的金属的毒性，但在盾牌地区的大部分地区，盐基阳离子正在枯竭，而在许多城市地区附近则表现出丰富的盐基阳离子。因此，在我们能够预测各种分水岭干扰的单一或综合影响或预测在消除压力因素后恢复或重新定居的可能轨迹之前，需要更好地了解陆地/水生联系。加拿大萨德伯里金属开采和冶炼综合体周围受到严重影响的分水岭是北方分水岭多重应激源长期影响的经典例子。在这里，尽管在空气污染控制和大规模的土地开垦工作上投入了超过10亿美元的资金，但在近岸环境中恢复敏感无脊椎动物物种的工作落后于清理工作数十年。我们的研究使用空间调查和野外和实验室实验相结合的方法来检测、测量和评估陆生/水生联系对无脊椎动物群落恢复的重要性。我们还比较和对比了不同干扰类型(林业、火灾、采矿)在安大略省各地研究地点的影响，并研究了景观和当地栖息地因素在形成底栖无脊椎动物群落中的作用。我们的研究旨在提高我们对从干扰中恢复的基本过程的理解，并帮助生态风险管理人员更有效地设计

Clean water and diverse communities of aquatic biota are so dependent on watershed processes that they can be considered "products" of healthy forests in the Boreal Shield Ecozone. Carbon inputs from the terrestrial watershed are key determinants of productivity of dilute lakes, with both particulate and dissolved (DOC) carbon contributing heavily to the foodwebs of receiving lakes and streams. Base cations from forest soils also affect a vast array of aquatic processes, including the toxicity of introduced metals, but base cations are exhibiting depletions across much of the Shield region, while showing enrichment near many urban areas. Better understanding of terrestrial/aquatic linkages is therefore needed before we can predict the single or combined effects of various watershed disturbances or predict the likely trajectories that recovery or recolonization will take after stressors have been removed. The severely impacted watersheds surrounding the metal mining and smelting complex in Sudbury, Canada are classic examples of the protracted effects of multiple stressors in Boreal watersheds. Here, even after more than $1B investment in air pollution control and extensive land reclamation work, recovery of sensitive species of invertebrates in nearshore environments lags decades behind the cleanup efforts. Our study uses a combination of spatial surveys and field and laboratory experiments to detect, measure and evaluate the importance of terrestrial/aquatic linkages in relation to the recovery of invertebrate communities. We also compare and contrast the effects of different disturbance types (forestry, fire, mining) at study sites across Ontario and examine the role of landscape and local habitat factors in shaping benthic invertebrate communities. Our studies are designed to improve our understanding of the fundamental process of recovery from disturbance and to help ecological risk managers design more effective