Coupling the soil catena to the runoff enigma in Canada's Boreal Plain

将土壤链与加拿大北方平原径流之谜联系起来

• 批准号: RGPIN-2019-06470
• 负责人: Ketcheson, Scott
• 金额: $ 1.82万
• 依托单位: Athabasca University
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2021
• 资助国家: 加拿大
• 起止时间: 2021-01-01 至 2022-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=738929
• 关键词: Coupling; soil; catena; runoff; enigma

Canada's Boreal Plain stretches from the Rockies to Lake Winnipeg and the Prairies to the northern Taiga ecozones. The amounts of water flowing in its rivers and streams depend on how rainfall is divided between losses to the atmosphere through evaporation and transpiration and that which is stored in its lakes, wetlands, and soils. Determining the redistribution and storage of water between landscapes and waterways is key to understanding stream flows at larger scales. Despite the importance of understanding the flow of water to all aspects of our environment and activities, we do not have enough data to quantify and interpret our studies: runoff in the Boreal Plain remains an enigma. This research aims to understand runoff processes in the mid-to-lower regions of the Athabasca River Basin. However, hydrological measurements for these regions are scant, which limits our ability to interpret and predict runoff variability and trends. Given the large-scale industrial activities in this region, a changing climate, and recent natural disasters, we urgently need to solve this runoff enigma. A soil catena is a sequence of soils found down a slope. The soil hydraulic properties and layering in a catena greatly affect local runoff. Rainfall events on forested hillslopes can cause transient runoff that impacts adjacent wetlands, lakes, and streams. Enhanced hydrological connectivity between hillslopes and wetlands through transient runoff could result in a significant additional mechanism of runoff generation not yet considered. The hydraulic properties of the soils in a catena affect the timing and magnitude of transient runoff, so understanding these properties is crucial to understanding the hydrological processes and stream flows at both the local and regional scales. Since flow pathways affect water quality, transient runoff pathways could also result in geochemical changes that influence the health of downstream ecosystems. The long-term objectives are to identify and understand new mechanisms of water movement within the Boreal Plain and to evaluate their significance for regional-scale runoff. This field-based program will study the transient hydrological connections between wetlands and forested hillslopes. Soil layering along the catenae of multiple hillslopes will be evaluated to assess spatial variability and runoff potential. Laboratory measurements of soil hydraulic properties will complement field results. Innovative hillslope runoff stations at forestland-wetland boundaries will measure lateral hillslope runoff during rainfall events. Subsurface flow pathways along the soil catenae will be determined using tracer tests. These new mechanisms of water movement will be combined with existing hydrological models and compared to observations of water availability and quality within the Athabasca River Basin. This is an important contribution to the conceptualization of water movement in this industrially and ecologically significant region.

加拿大的北方平原从落基山脉到温尼伯湖，大草原延伸到北部的塔加生态。流动在其河流和溪流中的水量取决于降雨如何通过蒸发和翻译以及存储在其湖泊，湿地和土壤中的降雨量之间。确定景观和水道之间的水的重新分布和存储是理解较大尺度的溪流流量的关键。尽管了解水流到环境和活动各个方面的重要性，但我们没有足够的数据来量化和解释我们的研究：北方平原的径流仍然是一个谜。这项研究旨在了解阿萨巴斯卡河流域中部到下地区的径流过程。但是，这些区域的氢测量值很少，这限制了我们解释和预测径流变异性和趋势的能力。鉴于该地区的大规模工业活动，气候变化和最近的自然灾害，我们迫切需要解决这种径流的谜团。土壤catena是在斜坡下发现的一系列土壤。土壤水解特性和catena中的分层极大地影响了局部径流。森林山坡上的降雨事件会导致瞬态径流，从而影响邻近的湿地，湖泊和溪流。通过短暂的径流增强了山坡和湿地之间的液压连通性可能会导致尚未考虑径流产生的重要机制。 CATENA中土壤的水解特性会影响瞬态径流的时机和幅度，因此了解这些特性对于理解局部和区域尺度上的水文过程和流动至关重要。由于流动途径会影响水质，因此瞬态径流途径也可能导致地球化学变化，从而影响下游生态系统的健康。长期目标是识别和理解北方平原中水运动的新机制，并评估其对区域尺度径流的重要性。该基于现场的程序将研究湿地和森林山坡之间的短暂氢连接。将评估沿多个山坡的Catenae的土壤分层，以评估空间变异性和径流电位。土壤水解特性的实验室测量将补充现场结果。林地 - 韦兰边界的创新山坡径流站将在降雨活动期间测量侧面山坡径流。将使用示踪剂测试确定沿土壤Catenae的地下流道。这些新的水运动机制将与现有的液压模型相结合，并与Athabasca河流域内的水的可用性和质量观察相比。这是对这个工业和生态意义上的水运动概念化的重要贡献。