Carbon cycling in acidic waters and implications for metal bioremediation University of Portsmouth in United Kingdom

Applications are invited for a fully-funded three year PhD to commence in October 2025.

The PhD will be based in the Faculty of Health and Science, and will be supervised by Dr Carmen Falagan , Dr Kenneth Wasmund , and Professor Joy Watts (University of Portsmouth), and Dr Javier Sánchez-España (Center for Astrobiology, Spain).

Candidates applying for this project may be eligible to compete for one of a small number of bursaries available. Successful applicants will receive a bursary to cover tuition fees for three years and a stipend in line with the UKRI rate (£19,237 for 2024/25).Bursary recipients will also receive a £1,500 p.a. for project costs/consumables.

Costs for student visa and immigration health surcharge are not covered by this bursary. For further guidance and advice visit our international and EU students ‘Visa FAQs’ page .

The work on this project could involve:

• Field trip to an acidic environment (e.g. Spain) for sample collection for the isolation of microorganisms.
• Cultivation of acidophilic microorganisms, including microalgae and heterotrophic bacteria.
• Working with microorganisms under anaerobic conditions (e.g. use of anaerobic chamber) and use of bioreactors.
• DNA-stable isotope probing experiments to trace carbon flows in microbial communities.
• Molecular microbiome profiling and bioinformatic analysis on collected DNA from environmental samples and laboratory experiments.

Project description

Acidic environments, for example, acid mine drainage, are one of the most hostile, extreme environments on Earth. However, these challenging environments host a diverse range of microorganism including bacteria, archaea and microalgae. This PhD will study the microbiology of acidic environments with a central aim to uncover the transfer of organic carbon through microalgae to the bacteria and archaeal populations inhabiting these extreme environments. This knowledge is crucial for enhancing bioremediation efforts to combat pollution, especially the removal of metals using acidophilic sulfate-reducing microorganisms.

The central objective of this PhD is the identification and characterisation of acidophilic primary producers (microalgae) to enhance carbon production and the heterotrophic acidophiles that consume the algal biomass. The PhD will involve the use of cultivation techniques, molecular biology techniques including next-generation sequencing, and DNA-based stable isotope probing, to identify both culturable and unculturable microorganisms involved in organic carbon degradation. Such approaches will enable a new understanding of the carbon pathways in acidic environments that remain largely understudied.

The project will not only advance our understanding of fundamental ecological and biogeochemical processes in extreme acidic environments, but also provides insights that can contribute to the development of sustainable strategies for the bioremediation of these ecosystems, especially in mining-impacted environments. The research promises to improve water quality in these acidic ecosystems, making a valuable contribution to environmental science and bioremediation efforts.

The PhD student will benefit from working in an interdisciplinary project with an international supervisory team (University of Portsmouth, UK, and Center for Astrobiology, Spain), and collaborations with excellent external institutes (e.g. University of Southampton), with good opportunities for training and career development.

General admissions criteria

You'll need a good first degree from an internationally recognised university (minimum upper second class or equivalent, depending on your chosen course) or a Master’s degree in an appropriate

subject. In exceptional cases, we may consider equivalent professional experience and/or qualifications. English language proficiency at a minimum of IELTS band 6.5 with no component score below 6.0.

Specific candidate requirements

• Microbiology laboratory skills.
• Basic knowledge in bioinformatics or willingness to learn.
• Basic mathematics skills for chemistry (desirable but not essential).
• Independent working skills.
• Good communication and teamwork skills.

How to Apply

Please note that email applications are not accepted. If you have any project-specific questions please contact Dr Carmen Falagan ( [email protected] ) quoting the project code.

When you are ready to apply, you can use our online application form . Make sure you submit a personal statement, proof of your degrees and grades, details of two referees, proof of your English language proficiency and an up-to-date CV.  Our ‘ How to Apply ’ page offers further guidance on the PhD application process.

If you want to be considered for this funded PhD opportunity you must quote project code ELS50220125 when applying.