Reach-scale morphodynamics of gravel bed streams

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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.