Top-down controls of microbial biomass in supraglacial habitats

Applicants are invited for a PhD fellowship/scholarship at Graduate School of Technical Sciences, Aarhus University, Denmark, within the Environmental Science programme. The position is available from 15 January 2027 or later. You can submit your application via the link under 'how to apply'.

Title:
Top-down controls of microbial biomass in supraglacial habitats

Research area and project description:
The Department of Environmental Science at Aarhus University, Denmark, is offering a PhD position in Arctic microbial ecology, starting 15 January 2027 or earliest possible thereafter.

The overarching aim of this PhD project is to uncover the top-down controls regulating algal and cyanobacterial biomass on the surface of the Greenland Ice Sheet. This is part of a collaboration between Aarhus University and Copenhagen University to identify how viruses, grazers and parasitic fungi influence primary producer populations in supraglacial habitats. The project is funded by the Independent Research Fund Denmark.

The project in a nutshell: Glaciers and ice sheets are increasingly recognized as dynamic ecosystems, home to diverse and metabolically active microbial life. During the summer melt season, eukaryotic algae such as Chlorophyceae and Streptophyta emerge on the snow and on the living skin of ice surfaces of the Greenland Ice Sheet, reducing surface albedo and accelerating melt. Cryoconite holes, which are sediment-filled melt pockets perforating the glacier surfaces, are dominated by cyanobacteria. These phototrophic communities are key players and ecosystem engineers in supraglacial (i.e., the different habitats at the surface of glaciers and ice sheets) biogeochemistry and ice melt. However, while the roles of microbial primary producers have been well documented, the fate of their biomass and the extent to which it is shaped by top-down biological controls remains largely unexplored. 

The role of the PhD student in this project will be particularly focused on the following objectives: 1) the characterization of the abundance, community structure, and grazing activity of protozoan consumers in cryoconite holes and ice surface and 2) the determination of the occurrence, infection dynamics, and ecological effects of chytrid fungi on algal populations in different supraglacial habitats. 

The PhD student will closely collaborate with a postdoc at Copenhagen University who will investigate the role of viruses on microbial mortality on glaciers. Furthermore, to contextualise viral infection, grazing and fungal infection rates, the PhD student will collaborate and have a 3-month international stay at Marseille University to use empirical data to develop a mortality model for supraglacial algae and cyanobacteria, quantifying losses attributable to viral lysis, grazing, and parasitism.

You must upload a project description (not AI generated) about how do you intend to approach the objectives of the project.

Project description (½-4 pages): This document should describe your ideas and research plans for this specific project. If you wish to, you can indicate an URL where further information can be found.

Qualifications and specific competences:
We are searching for a highly motivated candidate who has an M.Sc. degree in biology, microbiology, environmental sciences, ecology, or closely related fields.

Demonstrated oral and written communication skills in English are required. The applicant is expected to present results at international conferences and publish them in international peer-reviewed journals. The applicant should be interested in working in an international and interdisciplinary academic environment. Further, we would prefer candidates with the following qualifications:

• Experience in microbial ecology techniques (e.g., fluorescence microscopy, molecular ecology, incubation experiments, use of isotopes).
• Understanding and experience of work in remote conditions (e.g., Arctic, glaciers) and an ability to organize and participate in complex fieldwork.
• Good skills in laboratory work.
• An ability to communicate effectively in English and contribute to dissemination and reporting research outcome in high-impact scientific journals.
• Collaborative and interpersonal skills and will to contribute positively to the working environment.

Place of employment and place of work:
The place of employment is Aarhus University, and the place of work is Department of Environmental Science, Aarhus University, Frederiksborgvej 399, DK-4000, Roskilde, Denmark.

Contacts:
Applicants seeking further information regarding the PhD position are invited to contact: 

• Alexandre Anesio, ama@envs.au.dk (main supervisor)
• Rumakanta Sapkota, rs@envs.au.dk (co-supervisor)

For information about application requirements and mandatory attachments, please see our application guide. If answers cannot be found there, please contact:

• admission.gradschool.tech@au.dk 

How to apply:
Please follow this link to submit your application. 

Application deadline is 15 September 2026 at 23:59 CEST.

Preferred starting date is 15 January 2027.

Please note: 

• Only documents received prior to the application deadline will be evaluated. Thus, documents sent after deadline will not be considered.
• The programme committee may request further information or invite the applicant to attend an interview.
• Shortlisting will be used, which means that the evaluation committee only will evaluate the most relevant applications.

Aarhus University’s ambition is to be an attractive and inspiring workplace for all and to foster a culture in which each individual has opportunities to thrive, achieve and develop. We view equality and diversity as assets, and we welcome all applicants. All interested candidates are encouraged to apply, regardless of their personal background. Salary and terms of employment are in accordance with applicable collective agreement.