Reach-scale morphodynamics of gravel bed streams

我提议的研究将调查溪流、河床侵蚀和植被生长之间的过程和相互作用，这些过程和相互作用决定了砾石床溪流的行为。特别是，我的小组将试图了解哪些环境变化可以被河道吸收，哪些可能会产生不稳定和不可预测的河道行为。最终，我们正在努力开发一个模型，既描述环境条件相对恒定时河流可能采取的平衡状态，也描述随着城市化和森林砍伐的增加而可能发生的变化的速度、性质和方向，以及气候变化导致的野火频率和水文制度的变化。了解这些动态对于有效管理河流生态系统和评估人类发展的风险至关重要，特别是在面对持续的气候变化和河流系统不断变化的情况下。我们将继续在FishTrap Creek进行实地研究，在那里我们可以观察该溪流对2003年一场严重野火的反应，我们将在不列颠哥伦比亚大学新建的水力学实验室启动一系列实验，该实验室名为山道水力学实验实验室(MCHEL)。这些实验将使我们能够模拟河流对不同程度干扰的反应，这反过来将帮助我们改进我们的理论模型，以预测河道行为。通过建立长期的实地研究站点，如在FishtraCreek的站点，进行河道动力学的实验室实验，以及开发各种数值和理论模型，我们将进一步提高我们了解河流对短期(十年)和较长期(数百年或数千年)环境变化的响应的能力。

My proposed research will investigate the processes and interactions between stream flow, bed erosion and vegetation growth that determine how gravel bed streams behave. In particular, my group will seek to understand which environmental changes can be absorbed by a stream channel, and which are likely to produce unstable and unpredictable channel behaviour. Ultimately, we are striving to develop a model that describes both the equilibrium state that streams are likely to adopt when environmental conditions are relatively constant, as well as the rate, nature and direction of the changes likely to occur in response to increasing urbanization and deforestation, as well as altered wildfire frequencies and hydrologic regimes resulting from climate change. Gaining an understanding of these dynamics is critical to the effective management of riverine ecosystems and risk assessment for human development, especially in the face of ongoing climate change and ever-increasing alterations to fluvial systems. We will continue to conduct field studies at Fishtrap Creek where we can observe the response of that stream channel to a severe wildfire in 2003, and we will initiate a series of experiments in a new hydraulic laboratory constructed at the University of British Columbia, called the Mountain Channel Hydraulics Experimental Laboratory (MCHEL). The experiments will allow us to model the response of a stream to disturbances of various magnitudes, which in turn will help us to refine our theoretical models for predicting channel behaviour. By establishing long-term field study sites like the one at Fishtrap Creek, conducting laboratory experiments on stream channel dynamics, and developing various numerical and theoretical models, we will further improve our ability to understand how streams respond to short term (decadal) and longer term (centuries or millennia) environmental changes.