| Summary: | 2016 Summer. Includes bibliographical references. Downed wood is a resource easily utilized by plants and animals from the forests to the sea and is essential for many ecosystems. The diverse benefits that wood brings to streams and riparian corridors are well documented by river scientists and wood re-introduction is commonly used as a river restoration tool. However, much of the existing work investigates the short-term impact of wood rather than its variability through time and legacy on the landscape. In this dissertation, I use the Slave River (water discharge=2-7 x103 m3 s −1 , channel widths=300-2000 m, drainage area=6x105 km2 ), and its receiving sedimentary basin, the Great Slave Lake (surface area=273 km2 , depths 20-600 m, volume 1000-2000 km3 ), in northern Canada to better understand wood transport dynamics of a major river basin across varied timescales from minutes to centuries and the influence of driftwood on shoreline landscape evolution. The four primary contributions of this work are: a comprehensive literature review and synthesis of wood transport in rivers worldwide (Chapter 1), new methods for monitoring and quantifying wood flux with timelapse cameras (Chapter 2), description of processes among driftwood, sediment, and vegetation that result in shoreline features that I have coined "driftcretions" (Chapter 3), and expansion of wood transport research into multiple timescales with a focus on how flow history impacts magnitude of wood flux (Chapter 4). In Chapter 1, I: qualitatively summarize existing transport research around flow, wood and reach characteristics, quantitatively consolidate and analyze wood mobility field data in relation to increasing channel size, identify disconnects between driving processes and how mobility is measured, and constrain and conceptualize thresholds between wood dynamic ii regimes. In Chapter 2, I introduce a cheap, useful and fast way to monitor and estimate wood flux with timelapse photography through the use of the metric p, the probability of ...
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