Oceanic food webs are among the most biologically productive systems on Earth and provide critical ecosystem services to humankind including food, climate regulation, nutrient cycling, and fisheries. Critical to their functioning, health, and the biodiversity they support are several globally significant processes. Oceanic food webs are fuelled by the biological carbon pump (BCP) that cycles food between the surface and seafloor through benthic-pelagic coupling. This supports energy flow through a food web from microbes to marine mammals. The mesopelagic zone (200-1,000m deep), is the vital link between the surface and seafloor. Food web health and biodiversity depend on maintaining this link through carbon flow to and from mesopelagic species, including fish, squid, microbes, and zooplankton.
Oceanic food webs are currently impacted by many anthropogenic activities, particularly climate-driven ocean changes, and fisheries that remove carbon (C) and high trophic level biomass and can impact non-target species. Moreover, threats such as those from deep-sea mining are expanding. Impacts from these will extend across all trophic levels and far deeper into the water column and down to the seafloor, but our understanding of the systems and impacts are mostly conceptual, with little attention paid to the actual processes supporting ocean health and functioning.
One management tool that can help protect and limit damage to marine ecosystems is the implementation of Marine Protected Areas (MPAs). OSPAR’s most recent MPA is the North Atlantic Current and Evlanov Sea basin (NACES) MPA. While the NACES MPA encompasses protection from the surface to the seafloor, our understanding of the NACES deep-sea ecosystems are extremely poor. As such, it is presently not possible to assess how effective the NACES MPA is with regards to preserving deep-sea biodiversity and ecosystem function in the NW Atlantic.
The PhD will be embedded within the EC Ocean SOS project and measure benthic C-demand at the abyssal seafloor and on seamounts using benthic respirometer landers, as well as microprofilers, and Aquatic Eddy Covariance systems. To document C flow through the benthos, stable isotope pulse-chase experiments will be undertaken in-situ. Biodiversity and C-flow to seafloor scavengers will be documented using baited camera landers and baited trap systems, specifically designed to be deployed to the relatively flat abyssal plain, as well as on more rugged terrain found on seamounts. Combining the aforementioned observations as well as observations on C-fluxes from sediment trap moorings will allow us to create novel linear inverse models (LIMs) of C-flows between the pelagic and benthic zones representing NACES. Ultimately, these LIMs will be forced by inputs from short-, medium-, and long-term scenarios of climate change and fisheries pressure (e.g., changes in C-input) to see how benthic ecosystem functions are maintained or altered in a anthropogenically-stressed ocean.
Director of Studies:
Prof. Andrew K. Sweetman (SAMS)
Supervisory Team:
Prof. Bhavani Narayanswamy (SAMS)
Dr Emma Cavan (Imperial College London)
Dr Henk Jan Hoving (Geomar)
Who can an applicant contact for further information about the project?
Prof. Andrew K. Sweetman
Who can an applicant contact for further information about the application process?
SAMS Graduate School: phd@sams.ac.uk
Closing Date for Applications: Friday 22nd May 2026
Interview Date: Thursday 18th June 2026 (morning)
Location: In person at SAMS
Start Date: 1st October 2026
Funding:
This is a 3.5-year PhD studentship, funded by the European Commission funded project ‘Ocean SOS’. Funding follows UKRI funding guidance and will cover UHI tuition fees and a maintenance stipend for a Home, EU or International student for 3.5 years.
This PhD project is registered through the University of the Highlands and Islands, and this page outlines the application procedure for UHI PhDs.
We adhere strictly to equality and diversity policies during all phases of recruitment so that we find the most talented and motivated students to join us.
Eligibility
To be eligible to study for a PhD at SAMS, you need to possess - in a relevant discipline and from a reputable institution:
- A Master's qualification and / or
- A Bachelor degree with first class or upper second-class Honours and / or
- Another qualification or substantial experience that demonstrates your academic competence to complete doctoral training successfully (to be approved by the UHI Research Degrees Committee on the recommendation of the SAMS Director).
Additionally, international students whose first language is not English and who do not hold a prior degree obtained in English must hold an IELTS qualification with a score of 6 or over in every section with a minimum score of 6.5 overall (6+ in writing), gained within two years prior to your registration date.
Please complete Section 1 – 4 of the application form.
Research Degree Student application form
Return your completed application form with all supporting documents listed below as one pdf to the email stated on the form.
Please ask your referees to complete and return the PhD Applicant Reference Request Form to phd@sams.ac.uk.
Applicant Reference Request form
Supporting Documentation Required
The following documents should be emailed with your application:
- CV
- Copies of all official qualification certificates and transcripts. If your official certificates/transcripts are not in English, they must be accompanied by a full certified translation provided by a professional translator/translation company.
- If English is not your native language, an English language test certificate (IELTS or equivalent), gained within the past two years;
- If you are not a UK national, a copy of the photo page of your passport. Also include any pages which indicate a right of abode in the UK;
- 2 academic references. If references are not available at the time of submission, they can be excluded; however, applicants are responsible for ensuring their referees submit the references to the email given on the application form by the application deadline.
For further information about the project, please contact: Prof. Andrew K. Sweetman
For administrative issues , and to submit your application, your first and main point of contact is the Postgraduate Academic Support Administrator who can be contacted by email to: phd@sams.ac.uk