E.U./U.K. nationals: PhD Studentship: Dam Beavers: Quantifying the Impacts of Nature's Water Engineers on the Fluvial Geomorphology and Flood Regimes of Streams and Rivers, Geography
- Professor Richard Brazier, College of Life and Environmental Sciences, University of Exeter
- Professor Karen Anderson, College of Life and Environmental Sciences, University of Exeter
- Dr Alan Puttock, College of Life and Environmental Sciences, University of Exeter
- Dr Stewart Clarke, National Trust
The Eurasian Beaver (Castor Fiber) was hunted to extinction in Great Britain and near-extinction in Europe. Over recent decades, it has made a comeback, with numbers now nearing 1 million in mainland Europe and with a number of reintroductions and licensed trials established in GB to improve understanding of the role that this ecosystem engineer might play if more widespread. Since beavers were absent from GB, landscapes have been modified extensively in support of agricultural intensification, with an emphasis upon the drainage of the land to deliver enhanced production of food. Waterways are now straightened and deepened, fields under-drained and often bare of vegetation, to maximise drainage efficiency, but with detrimental impacts downstream. Thus, there are very few, if any ‘natural’ streams or rivers in GB, which means that research is required to understand what impact beavers might deliver, as they return into densely populated, intensively-farmed ecosystems. This PhD will deliver new understanding of the ways in which streams and channels will respond to beaver activity and will therefore provide fundamental science to guide both decision and policymakers and land managers as to how to respond.
Project Aims and Methods
The overall aim of this project is to quantify the impacts that beavers will have on the fluvial geomorphology and flood regimes of a wide range of surface waters in Great Britain. It is noted here that the PhD student will both refine and redesign this project, as their ownership of the research develops, however we have established the following hypotheses to test:
- Beaver activity (particularly beaver dams) will force channel-planform change across a range of stream orders (at least 1st to 4th), increasing sinuosity, decreasing width:depth ratios and increasing the presence of multi-thread channels in the landscape, which engage more regularly with floodplains.
- Within-channel bed characteristics will be significantly altered via beaver dam construction, with along-channel heterogeneity of bed material increasing; becoming finer upstream of dams and coarser downstream.
- Channel long-profiles will be altered towards more step-formed geometry due to the presence of beaver dams and these geomorphic changes will persist, delivering changes to hydraulic behaviour along beaver-dammed reaches, when compared with non-dammed reaches.
- Beaver dammed channels will deliver flow attenuation, reducing peak flows and increasing lag times in a comparable manner to more conventional natural flood management techniques such as woody debris dams.
This award provides annual funding to cover UK/EU tuition fees and a tax-free stipend. For students who pay UK/EU tuition fees the award will cover the tuition fees in full, plus at least £15,285 per year tax-free stipend. Students who pay international tuition fees are eligible to apply, but should note that the award will only provide payment for part of the international tuition fee and no stipend.