Water, sediment and nutrient connectivity in engineered Prairie landscapes

加拿大人认为水是他们最重要的自然资源，并担心目前的管理制度不足以保护环境。在草原地区尤其如此，在这些地区，洪水、干旱和弥漫性农业污染是社会和经济成本方面最大的环境问题。我们应对水质过剩和短缺的能力取决于我们对径流、沉积物和营养物质可能在何时何地离开我们的土地，进入溪流、河流和湖泊的理解。连通性的概念旨在帮助量化这种可能性，但它尚未在高度受影响的农业草原景观中得到充分探索。拟议的研究计划将通过解决以下四个问题来填补这一空白：1)连通性是由一个主导流过程控制还是由多个控制？2)连接开始和停止的时空阈值是什么？3)如何管理雨水控制设施对自然连通性的增强或破坏作用？4)连通性预测框架应包括哪些基本要素？这项研究将在马尼托巴省的多个研究地点进行，以确保考虑到各种各样的草原景观。最先进的水文测量仪器和高端水质监测设备将用于监测水、沉积物和营养物质的运动。实地数据将在各个地点进行综合，以检查地形、空间尺度或雨水控制结构（如瓦片和沟渠网络、湿地排水系统或农场水坝）对连通性的影响。实地数据也将用于水文模型的发展和参数化。这项研究将提高我们对重度改变景观中流域动态的理解，并为培养草原水文学领域的新科学家提供一个独特的机会。其成果最终将通过指导水管理系统的发展来减少洪水风险、沉积物和营养物污染，从而使加拿大西部社区受益。

Canadians believe that water is their most important natural resource and worry that current management systems are not adequate for environmental protection. This is especially true in Prairie regions where floods, droughts and diffuse agricultural pollution are the greatest environmental issues in terms of social and economic costs. Our ability to deal with excesses and shortages of quality water rests on our understanding of when and where runoff, sediments and nutrients are likely to leave our lands and reach streams, rivers and lakes. The concept of connectivity is meant to help quantify this likelikood but it has not been fully explored in highly impacted, agricultural Prairie landscapes. The proposed research program will contribute to filling that gap by addressing four questions: 1) Is connectivity controlled by one dominant flow process or many?, 2) What are the temporal and spatial thresholds of connectivity initiation and cessation?, 3) How to manage the enhancing or disruptive effect of stormwater-control structures on natural connectivity?, and 4) Which essential elements should be included in connectivity prediction frameworks? The research will be done at multiple study sites in Manitoba to ensure that a good variety of Prairie landscapes is considered. State-of-the-art hydrometric instruments and high-end water quality monitoring devices will be used to monitor water, sediment and nutrient movement. The field data will be synthesized across sites to examine the effects of physiography, spatial scale or stormwater-control structures such as tile and ditch networks, wetland drainage systems or farm dams, on connectivity. Field data will also be used to inform hydrological model development and parameterization. This research will improve our understanding of watershed dynamics in heavily modified landscapes and provide a unique opportunity to train new scientists in Prairie hydrology. Its outcomes will ultimately benefit Western Canadian communities by guiding the development of water management systems toward reduced flood risk and sediment and nutrient contamination.