PhD Position in Nitrogen Isotope Biogeochemistry and Phytoplankton Ecology

100% / Expected start date is 1 June 2021 or later

The Aquatic and Isotope Biogeochemistry Research Group at the Department of Environmental Sciences, University of Basel ( invites applications for a PhD position in the field of nitrogen isotope biogeochemistry and phytoplankton ecology. The student will be part of a project investigating the validity of the diatom nitrogen isotope paleo-proxy in the marine and lacustrine environments through a combination of experimental and field studies. Research is planned in collaboration with scientists from Umea University, Sweden (Department of Ecology and Environmental Sciences) and the Max Planck Institute for Chemistry, Germany (Climate Geochemistry Department).

Your position

The analysis of the nitrogen (N) isotope composition of fossil shells (such as diatoms) is a powerful tool to study the aquatic N cycle of the past, but a thorough ground-truthing of the diatom N isotope proxy is still lacking. This PhD project aims to investigate nitrogen isotope fractionation in living diatoms during growth in the natural environment and in laboratory cultures. The goal is to determine relationships among the N isotope composition of the nitrate in the water, the diatom biomass and diatom shell-bound N. The project involves extensive laboratory work, where the PhD student will set-up and maintain diatom cultures for isotopic analyses. The PhD student will also have the opportunity to join oceanographic cruises on a sailing research yacht, as well as fieldtrips to Swiss lakes to collect water and phytoplankton samples. The overall goal of this project is to improve our understanding of how the isotopic signature of diatom shell-bound N is acquired during growth, which will contribute to validate the diatom N isotope proxy as a tool for paleoclimate reconstructions in both the marine and lacustrine environments.

Your profile

We are looking for a highly motivated candidate with a master's degree in environmental sciences, geosciences, biology, chemistry, or a related discipline. Candidates are expected to have a solid background and interest in limnology, oceanography, and biogeochemistry in aquatic systems in general. Experience with phytoplankton culturing and expertise in stable nitrogen isotope/mass-spectrometric techniques will be an advantage. Clean and precise work in the laboratory are a must. The ability to work both independently and within a team, as well as good communication skills including fluency in English are essential.

We offer you

The PhD project (100%) will be part of a research project funded for 4 years by the Swiss National Science Foundation. We offer an international, multidisciplinary work environment and excellent research infrastructure. Compensation will be according to the guidelines of the Swiss National Science Foundation (

Application / Contact
Please submit your complete application documents, including (i) a letter stating your research interests and motivation for applying for the position, your experience and skills, (ii) a CV, (iii) contact details of at least two references (one of these should be the main advisor of your master's thesis), and (iv) transcripts and diplomas of your bachelor's and master's degrees (if available) via our online recruiting platform.
We accept only online applications.
For further information please contact Dr. Anja Studer ( Review of applications will begin 1 May 2021 and will continue until the position is filled.