University of Exeter funding: NERC FRESH Geography PhD

Can beaver-modified ecosystems mitigate water quality deterioration caused by both point and diffuse source pollution? PhD in Geography (NERC FRESH) Ref: 3757

About the award


Lead Supervisor
Professor Richard Brazier, Department of Geography, College of Life and Environmental Sciences, University of Exeter

Additional supervisors:
Dr Gemma Coxon, School of Geographical Sciences, University of Bristol
Dr Alan Puttock, Department of Geography, College of Life and Environmental Sciences, University of Exeter
Stewart Clarke, National Trust

The NERC Centre for Doctoral Training in Freshwater Biosciences and Sustainability (GW4 FRESH CDT) provides a world-class doctoral research and training environment, for the next generation of interdisciplinary freshwater scientists equipped to tackle future global water challenges. GW4 FRESH harnesses freshwater scientists from four of the UK’s most research-intensive universities (Bath, Bristol, Cardiff and Exeter) plus world-class research organisations the Centre for Ecology and Hydrology (CEH) and British Geological Survey (BGS).

For an overview of the GW4 FRESH CDT please see website

Note, the research projects listed are in competition with other studentship projects available across the GW4 FRESH CDT Partnership. Up to 14 studentships will be awarded to the best applicants.

Project description:

Freshwater ecosystems in developed nations faces pressure from multiple stressors but in particular due to years of degradation of water quality due to the intensive management of catchments resulting from agriculture and point source pollution from high population densities. These stressors are likely to increase in the future as populations continue to expand, predicted changes due to climate lead to increased hydrological extremes and government resources for management and regulation become even more stretched.  Alongside the degradation of our surface waters, beavers have been reintroduced to Great Britain after an absence of ca. 400 years. Beavers are ecosystem engineers and keystone species with the ability to transform landscapes dramatically creating complex wetlands. Beaver engineering activity has been shown, in pilot work by the supervisory team, to influence water chemistry and therefore downstream water quality via both abiotic (construction of dams which trap nutrients) and biotic (uptake of nutrients by vegetation) processes. It is believed that there were two key mechanisms affecting the difference in water quality observed at a beaver sites: (1) flow was slowed resulting in the physical deposition of sediment and associated nutrients (2) the site increased in wetness altering the biogeochemical cycling of nutrients. 

Research undertaken elsewhere supports these findings but in very different ecosystems. The return of beaver to Great Britain, coincides with an identified need for a greater understanding of the pressures affecting freshwater ecosystems and new integrated solutions to address these pressures. Beaver created wetlands have the potential to address the stressors of poor water quality and habitat simplification together and in dynamic and potentially sustainable way. Now is the time to quantify the impacts of beaver upon sediment and macronutrient dynamics robustly in our freshwater ecosystems. 

The research will characterise the impact of beavers upon water quality across a range of sites where beavers are well established and a range of new locations managed by the National Trust where beaver reintroduction is scheduled, or is already underway.  The PhD student will be embedded in a research group already studying various aspects of beaver reintroduction including; hydrology, aquatic ecological status, socio-economic impacts, perceptions of beaver reintroduction and modelling to understand beaver habitat, population dynamics and impacts at the landscape scale.

The research will give the PhD student a unique opportunity to develop a growing body of work examining whether beaver can form a valuable component to multi-benefit, catchment management solutions.    Taking a Multiple-Before-After-Control-Impact experimental approach, this research will address the following hypotheses: 

1. Beaver pond and dam sequences act as sediment traps, storing significant amounts of sediment and reducing downstream suspended sediment concentrations, loads and yields. 
2. Beaver engineering activity delivers a positive impact on both diffuse water pollution from agriculture and point source pollution (for example from septic tanks, water treatment works) resulting in downstream reductions in nitrogen and phosphorus concentrations/loads/yields, driven by increased uptake by aquatic plants. 
3. Beaver ponds trap and store significant amounts of carbon, upstream of dam complexes and within pond sediments.
4. Impacts of beaver upon water quality are observed across a range of sites, scales and landuses, allowing mechanistic understanding to be upscaled via a suite of modelling tools, to predict the impacts of beaver on water quality at catchment scales.
The student will benefit from strong links to the National Trust and the Environment Agency and will have the opportunity to work closely with beaver reintroduction and catchment management projects. This will enable the student to see first-hand the work of research end-users and gain an understanding of the way in which their science can be used through implementation and wider stakeholder engagement. The student will be offered the opportunity to significant periods of time working directly with the National Trust and gain valuable experience of practical conservation and water management.

Real Life challenges this project will address
Water in our rivers faces multiple pressures with poor water quality posing a risk both to freshwater ecology, drinking and bathing water status. At the same time, Beaver reintroduction is progressing rapidly across Great Britain, with ca. 1000 animals already present in the wild and a significant number of partners (>20 to date) working with Prof Brazier’s group to run licensed reintroduction projects in diverse landscapes across GB. Beavers are hypothesised to impact water quality via both biotic and abiotic changes. Quantifying these impacts to test such hypotheses is critical to understand if impacts will be positive or negative across Great Britain and if Beaver have a valuable role to play as a component of water resource and catchment management strategies.

What you should know about this project
This project provides a unique opportunity to work with the UK’s leading group of ecohydrologists researching the reintroduction of beavers. The supervisory team includes academics from the University of Exeter – Prof Richard Brazier, who has a strong track-record in water chemistry and water quality research and Dr Alan Puttock, an early-career ecohydrologist who studies the ways in which freshwater systems change in response to beaver activity. The PhD student will also be supervised by Gemma Coxon, a hydrologist from the University of Bristol, whose numerically-strong approach to both empirical and model-based predictions of water quantity and quality will ensure that experimental design delivers data to support future prediction of beaver impacts. Dr Stewart Clarke will be the stakeholder supervisor, a strong scientist himself, Stewart brings freshwater science expertise as well as strong pathways to impact as the national-lead for the National Trust lead for Freshwater and Estuaries.

What expertise you will develop
The student will be based in the new Centre for Resilience in Environment, Water and Waste (CREWW), which is a £32M laboratory and training centre, co-funded by Research England and the Water Industry. CREWW will provide, free of charge to the project, access to world-class water quality analytical facilities and in-situ water quality monitoring equipment ( All training in laboratory and field-based approaches and associated data analysis will be provided. The student will also benefit from working with an Early Career Researcher as co-supervisor – Dr Gemma Coxon, who will bring rigorous approaches to paired-site data comparisons and a strong understanding of hydrology, to complement the water quality expertise within CREWW. Expertise in partnership working, including delivery of deep impact within a number of project partners (National Trust, water companies and the EA) will be central to the expertise developed through the co-created research program. This will result in the student becoming a leading expert in the impacts of beavers upon water quality, but also in how such understanding can transform the ways in which large organisations manage our fresh waters.

Why this project is novel
The impacts of beavers upon water quality and specifically both sediment and macro-nutrient cycles (Carbon/Nitrogen/Phosphorus) is not well understood, particularly in the densely populated, intensively managed catchments present across Great Britain (GB and NW Europe more broadly). The need to mitigate for excess levels of sediment and macronutrients in surface waters is clear, with only a small proportion of freshwaters meeting ‘good’ ecological status under the Water Framework Directive (2000) guidelines. Unnaturally high levels of macronutrients are a major cause of this poor freshwater health. Could beaver engineered habitats help to improve water quality in our catchments? Pilot work suggests that this may be the case, this PhD will address this important question.

Project specific enquiries should be directed to the lead supervisor, Professor Richard Brazier

Entry requirements

Applicants must demonstrate an outstanding academic record: at least a 2:1 undergraduate degree or equivalent, or relevant masters degree.

In addition to your academic record, selection will be based on the following criteria:

  • Why you are keen to pursue a freshwater bioscience PhD
  • What experience you have of freshwater research and interdisciplinary work
  • Whether you have the necessary personal and academic skills to complete a PhD project
  • Whether this scheme is suited to you and likely to best contribute to your career.

English requirements
If English is not your first language you will need to have achieved at least 6.5 in IELTS (and no less than 6.5 in any section) by the start of the programme.

How to apply

You will need to complete an application to the GW4 FRESH CDT for an “offer of funding”.

Please complete the application form at also sending a copy of your CV and a covering letter to the CDT by 9:00 on 16th December 2019.

After the closing deadline all applications and CVs will be forwarded to the lead Supervisor of the project(s) you have selected. They will interview you at a mutually convenient date in January 2020 (tbc) and submit their preferred candidate to FRESH CDT.

Shortlisted candidates will be invited to a panel interview in Cardiff in the week commencing 17th February 2020.  Further details will be included in the shortlisting letter

For further details regarding the application process please see the following web page

You do NOT need to apply to the University of Exeter at this stage - only those applicants who are successful in obtaining an offer of funding from the DTP will be required to submit an application to study at Exeter.

Data Protection
During the application process, the University may need to make certain disclosures of your personal data to third parties to be able to administer your application, carry out interviews and select candidates.  These are not limited to, but may include disclosures to:

the selection panel and/or management board or equivalent of the relevant programme, which is likely to include staff from one or more other HEIs;
administrative staff at one or more other HEIs participating in the relevant programme.
Such disclosures will always be kept to the minimum amount of personal data required for the specific purpose. Your sensitive personal data (relating to disability and race/ethnicity) will not be disclosed without your explicit consent.


Application deadline:16th December 2019
Value:3.5 year studentship consisting of full UK/EU tuition fees, as well as a Doctoral Stipend matching UK Research Council National Minimum (£15,009 for 2019/20)
Duration of award:per year
Contact: PGR Enquiries