Role and ecological impact of groundwater in delivering phospohorus to agricultural streams

加拿大各地的溪流、河流和湖泊受到包括农业在内的人类活动过量输入磷的威胁。过量的磷会导致有害的藻类水华，破坏水生生态系统，并污染饮用水水源。这具有严重的经济、生态和社会影响。尽管进行了大量的经济投资，并广泛实施了农业管理做法，以尽量减少对地表水的磷投入，但水质的改善有限。目前的做法普遍缺乏对来自地下水的磷输入的考虑，尽管这一途径可能很重要，并可能在解释管理做法的有限成功方面发挥关键作用。拟议的项目将把新的实地调查与最先进的计算机建模和开发用户友好的决策支持工具相结合，以评估地下水在向农业溪流输送磷方面的贡献和生态影响。这包括增进对连接农田和河流的地下水-地表水过渡带中发生的复杂的相互作用的水文和生物地球化学过程的了解，以及评估河流对地下水磷输入的生态反应。迫切需要产生新的科学认识和工具，以指导旨在恢复和保护加拿大各地地表水的农业养分管理计划和政策。该项目将汇集大学和政府研究人员、政府机构和保护当局，他们将共同努力建立和应用研究成果，以做出明智的管理和政策决策，在10年内使加拿大受益。这项研究将涉及一名博士后研究员、四名研究生和九名本科生，他们将通过与环境管理和政策组织的互动获得尖端的多学科培训，并获得宝贵的现实世界经验。

Streams, rivers and lakes across Canada are threatened by excessive inputs of phosphorus from human activities including agriculture. Excess phosphorus leads to harmful algal blooms, impairs aquatic ecosystems, and contaminates drinking water sources. This has severe economic, ecological and societal implications. Despite large economic investments and widespread implementation of agricultural management practices aimed at minimizing phosphorus inputs to surface waters, water quality improvements have been limited. Current practices generally lack consideration for phosphorus inputs from groundwater although this pathway may be important and may play a key role in explaining the limit success of management practices. The proposed project will combine novel field investigations with state-of-the-art computer modeling and the development of user-friendly decision support tools to evaluate the contribution and ecological impact of groundwater in delivering phosphorus to agricultural streams. This includes advancing understanding on the complex interacting hydrological and biogeochemical processes occurring in the groundwater-surface water transition zone connecting agricultural lands to streams, as well as evaluating the stream ecological response to groundwater phosphorus inputs. The new scientific understanding and tools that will be generated are urgently needed to guide agricultural nutrient management programs and policy aimed at restoring and protecting surface waters across Canada. This project will bring together university and government researchers, government agencies and a conservation authority who will work together to establish and apply the research findings to make informed management and policy decisions that will benefit Canada within a 10-year time frame. The research will involve one postdoctoral fellow, four graduate students and nine undergraduate students who will obtain cutting-edge multidisciplinary training and gain valuable real-world experience through interaction with environmental management and policy organizations.