Reach-scale morphodynamics of gravel bed streams

我提议的研究将调查水流、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河床的行为。特别是，我的小组将试图了解哪些环境变化可以被流通道吸收，哪些可能产生不稳定和不可预测的通道行为。最终，我们正在努力开发一个模型来描述当环境条件相对恒定时，河流可能采用的平衡状态，以及随着城市化和森林砍伐的增加，以及气候变化导致的野火频率和水文制度的改变，可能发生的变化的速度、性质和方向。了解这些动态对于河流生态系统的有效管理和人类发展的风险评估至关重要，特别是在面临持续的气候变化和河流系统不断增加的变化的情况下。我们将继续在Fishtrap Creek进行实地研究，在那里我们可以观察到该河道对2003年严重野火的反应，我们将在不列颠哥伦比亚大学新建的一个名为“山地河道水力实验实验室”（MCHEL）的水力实验室开展一系列实验。这些实验将使我们能够建立流对各种量级干扰的响应模型，这反过来将帮助我们完善预测通道行为的理论模型。通过建立像Fishtrap Creek这样的长期实地研究地点，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如何响应短期（十年）和长期（世纪或千年）环境变化的能力。

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.