Influence of lakes on catchment hydrology and stream temperature

湖泊对流域水文和河流温度的影响

• 批准号: RGPIN-2018-04637
• 负责人: Leach, Jason
• 金额: $ 1.65万
• 依托单位: Trent University
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2018
• 资助国家: 加拿大
• 起止时间: 2018-01-01 至 2019-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=656891
• 关键词: Influence; lakes; catchment; hydrology; stream

Climate change, forest disturbance, and urbanization are having a profound impact on the health of streams and their aquatic ecosystems. Developing a process understanding of how these environmental changes are impacting streamflow regimes and water quality is critical for effective management of our water resources. A glaring knowledge gap in our understanding of how catchments respond to environmental change is the role of lakes on downstream hydrology and water quality. Empirical studies have highlighted the important influence of lakes on stream water quality at landscape scales, even when lakes comprise just a small fraction of the landscape area. However, only a few studies have focused on the hydrologic and thermal processes underpinning these landscape patterns. In addition, most research has focused on large lakes and their inlet and outlet streams; however, small lakes are prevalent in glaciated landscapes but little is know about their influence on catchment hydrology. Important questions about lake-stream networks include: How do lakes influence downstream flow regimes and water quality? How far downstream do these lake effects persist? How does the lake-stream network structure impact streamflow and water quality at catchment scales? Are catchments with lakes more resilient to environmental change than catchments without lakes? The proposed research will address these questions using a combination of field and modelling approaches. Field research will be conducted at research catchments containing lake-stream networks in the rain-on-snow zone of the southern Coast Mountains in British Columbia. The field work will aim at characterizing the physical processes controlling the hydrology and thermal regimes of these catchments and their lake-stream networks. Both streamflow and water temperature are critical influences on fish growth, development, survival and distribution. The process knowledge gained from the field studies will be used to build and test computer models to improve our ability to predict effects of climate change and forest disturbance, and the role of lakes, on streamflow and water temperature. This model building and testing framework will drive rapid advances in catchment hydrology understanding, which will be critical for developing tools to effectively manage these systems.

气候变化、森林破坏和城市化正在对河流及其水生生态系统的健康产生深远影响。发展一个过程的理解，这些环境变化如何影响径流制度和水质是我们的水资源的有效管理的关键。在我们对集水区如何应对环境变化的理解中，一个明显的知识空白是湖泊对下游水文和水质的作用。实证研究强调了湖泊对河流水质在景观尺度上的重要影响，即使湖泊只占景观面积的一小部分。然而，只有少数研究关注这些景观格局背后的水文和热力过程。此外，大多数研究都集中在大型湖泊及其入口和出口流，然而，小湖泊普遍存在于冰川景观，但很少有人知道他们对流域水文的影响。关于湖流网络的重要问题包括：湖泊如何影响下游水流状态和水质？这些湖泊的影响会持续到下游多远？湖溪网络结构如何影响集水区尺度的流量和水质？有湖泊的集水区是否比没有湖泊的集水区更能适应环境变化？拟议的研究将使用现场和建模方法相结合来解决这些问题。实地研究将在不列颠哥伦比亚省南部海岸山脉雨雪带的湖流网络研究集水区进行。实地工作的目的是描述控制这些集水区及其湖流网络的水文和热状况的物理过程。径流和水温对鱼类的生长、发育、存活和分布都有重要影响。从实地研究中获得的过程知识将用于建立和测试计算机模型，以提高我们预测气候变化和森林干扰的影响以及湖泊对径流和水温的作用的能力。这一模型构建和测试框架将推动流域水文理解的快速发展，这对于开发有效管理这些系统的工具至关重要。