About the Project
We are seeking a highly capable candidate for an exciting PhD opportunity developing and applying new methods for the quantification of natural organic compounds in freshwater ecosystems in the UK, offering 4 years funding and a full UKRI Research Training Support Grant. This studentship is part of the large European Research Council-funded REFRESH project running for 5 years to research the role of dissolved organic matter (DOM) as a nutrient resource in freshwater systems, led by Professor Penny Johnes, at the University of Bristol.
Dissolved organic matter (DOM) is the principal form of organic matter in terrestrial freshwaters and is one of the largest fast-cycling reservoirs of organic matter globally. It has a carbon pool-size equal to the atmosphere and constitutes up 20% of the organic carbon budget of the Earth.[1] It is an operationally derived fraction defined by passing through a filter of size 0.2-0.7 μm, the remaining organic matter being particulate organic matter (POM).[2] It derives from an admixture of autochthonous (aquatic plants, algae) and allochthonous (soils, terrestrial plants) along with various anthropic loadings. Thus, at a molecular level the DOM pool comprises thousands of individual compounds including pharmaceuticals (and their metabolites), personal care products, detergents, peptides, free amino acids, amino sugars, lipids, organophosphates, urea, N-bearing compounds and breakdown products from natural biopolymers such as chitin, lignin and suberin. [3,4] Despite having been the focus of research for nearly 100 years, the functional roles and ecological impact that DOM has in aquatic ecosystems is still largely unknown.
Target compound analysis is already widely deployed to quantify emerging contaminants in DOM, predominantly arising from pharmaceuticals, illicit drugs and personal care products, largely for regulatory purposes.[5] Methodologies for quantifying key anthropic chemicals are now highly refined, covering up to 100s of targets in a single analysis, and are deployed globally. However, methodological approaches that speak to the larger, natural fraction of DOM are less developed and analogous workflows for the simultaneous quantification of multiple compounds are virtually non-existent. Creating workflows for the large-scale quantification of non-anthropic compounds, that could be applied widely and at volume, would enable fundamental aspects of DOM such as its formation, molecular fate and interaction with living organisms to be better explored. The overarching goal being to create a new means of assessing DOM to rapidly determine the ability of waters to support various ecosystem services underpinning a healthy biome and, where such systems are failing, determine the underlying stressors responsible. The student will work closely with the wider REFRESH team of investigators, postdoctoral researchers and research technicians, including another PhD student studying isotopic approaches to identify DOM utilisation with a particular focus on P uptake in freshwaters and a third PhD student studying cellular DOM metabolism in freshwater microbial communities.
- Hedges, J.I. (1991) Marine Chemistry, 39 (1–3), 67–93.
- Hartnett, H.E. (2018). In: White, W.M. (eds) Encyclopedia of Geochemistry. Encyclopedia of Earth Sciences Series. Springer, Cham. 375-378.
- Pemberton, J.A., Lloyd, C.E.M., Arthur, C.J., Johnes, P.J., Evershed, R.P. (2019) Rapid Communications in Mass Spectrometry, 11/19, 8618.
- Lloyd, C.E.M., Nena-Rivera, L., Pemberton, J., Johnes, P.J., Jones, D.L., Yates, C.A., Evershed, R.P. (2022) Biogeochemistry, 164, 29-52.
- Petrie, B., Barden, R., Kasprzyk-Hordern, B. (2015) Water Research, 72, 3-27.
Training and skills
This opportunity will provide a prodigious level of training with access to state-of-the-art analytical facilities and instruction in advanced hyphenated mass spectrometric techniques (e.g. GC/Q-TOF MS, GC-Orbitrap MS, LC-QQQMS, LC-Orbitrap MS) and biogeochemical methods. The student will also gain experience in working within a large, multidisciplinary research team with opportunities to collaborate with international partners and present at national and international conferences.
This project will be supervised and led by Prof. Ian Bull and co-supervised by Prof. Penny Johnes, both at the University of Bristol. It will also benefit from collaboration with project partners across multiple institutions. The student will join a dynamic research environment based in the Organic Geochemistry Unit (OGU) at the University of Bristol but will also visit Bangor University and UKCEH in Wallingford to take advantage of training and research opportunities.
Candidate Requirements
The successful candidate will be expected to meet the following criteria:
- Hold or expect to obtain at least a first-class or upper second-class honours degree in Environmental Science, Chemistry, Biology, Hydrology or a related discipline
- Have good laboratory skills and some experience in analytical techniques
- Demonstrate excellent organisational and time management abilities
- Show proficiency at analytical development, both instrumental and laboratory based
- Have good mathematical, coding and statistical skills
Scholarship
A fully funded UKRI PhD studentship including UK fees, a tax-free stipend at the UKRI minimum rate (£19,237 in 2024-25) and a full UKRI Research Training Support Grant (RTSG) to support project costs, training and travel is available at Bangor University, linked to a major UKRI funded programme led by the University of Bristol. Study will begin in September 2025 and is funded for four years. The deadline for applications is 31st January 2025.
Useful Links
For informal enquiries, please contact the lead supervisor, Prof. Ian Bull (ian.d.bull@bristol.ac.uk).
How to Apply: please apply through the following link, selecting the Chemistry (PhD) option at https://www.bristol.ac.uk/study/postgraduate/apply/
Application deadline: 31 January 2025
