Doctoral position in biochemistry/isotope geochemistry including radiocarbon | Universität zu Köln

PhD Position – Microbial Communities in Arctic Permafrost

University of Cologne has 6 Faculties covering a broad spectrum of disciplines and has developed an internationally outstanding research profile. The PhD project will focus on characterizing microbial communities and their role in carbon cycling in permafrost soils in a warmer and wetter Arctic. This includes microbial activity measurements and the use of carbon isotopes (¹³C, ¹⁴C) to quantify carbon uptake, respiration, and sources of CO₂ emissions. A further focus is on assessing how enhanced plant‑derived carbon inputs and mineral‑associated carbon stabilization influence microbial processes. The work will be carried out in close cooperation with national and international partners in the Institute of Geology and Mineralogy, Organic Geochemistry & Radiocarbon group.

YOUR TASKS

• Planning and conducting field measurements in Arctic regions including organising fieldwork and logistics, sampling of sediments, water, and measuring CO₂ and CH₄ fluxes
• Analyzing organic matter composition and microbial communities using organic‑geochemical techniques
• Planning and conducting laboratory experiments
• Applying and improving existing methods (e.g., CO₂ and CH₄ samplers, vacuum systems)
• Analyzing data using statistical methods
• Publishing results in peer‑reviewed journals and at conferences/meetings

YOUR PROFILE

• M.Sc. in geosciences, environmental sciences, chemistry or related subjects
• Willingness and ability to participate in several 2–3 week long field campaigns in the Arctic
• Pronounced interest and excellent background in biogeochemical cycles, isotope geochemical and/or organic geochemical methods
• Creative ability to develop digital solutions for data analysis
• Ability to work well independently and within a team
• Strong interest in technical and analytical work
• A high level of competence in spoken and written English

WE OFFER

• 3‑year doctoral position
• A diverse working environment with equal opportunities
• Support in balancing work and family life
• Extensive advanced training opportunities
• Occupational health management offers
• Flexible working time models
• Opportunity to work remotely

The University of Cologne promotes equal opportunities and diversity. Women will be considered preferentially in accordance with the Equal Opportunities Act of North Rhine‑Westphalia (Landesgleichstellungsgesetz – LGG NRW). We also expressly welcome applications from all suitable candidates regardless of gender, nationality, ethnic and social origin, religion, disability, age, sexual orientation and identity.

Upon allocation of funds the position is available from 1 May 2026 on a part‑time basis (27.88 hours per week) and is limited for a fixed term until 30 April 2029. If the applicant meets the relevant wage requirements and has the appropriate personal qualifications, the salary is based on remuneration group 13 TV‑L of the German public sector pay scale.

Please apply online with proof of the required qualifications (letter of motivation, CV, list of publications, copies of certificates) without a photo at . The reference number is Wiss . The application deadline is 23 March 2026.

For further inquiries, please contact Professor Dr. Janet Rethemeyer ((email protected) ) and take a look at our FAQs.