The Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research (AWI) is a member of the Helmholtz Association (HGF) and funded by federal and state government. AWI focuses on polar and marine research in a variety of disciplines such as biology, oceanography, geology, geochemistry and geophysics, thus allowing multidisciplinary approaches to scientific goals.

PhD position "Effects of ocean alkalinity enhancement on microbial communities" (m/f/d)


Negative emission technologies (NETs), as accompanying approaches to greenhouse gas reduction, might play a substantial role in the future to reach the ambitious goals of the Paris Agreement (COP21). However, the current knowledge on NETs is still incomplete and there is an urgent need for research, especially considering possible negative ecosystem side effects. One of the most promising NET technologies is based on the application of fast weathering minerals (e.g. Olivine) that consume CO2 when dissolving (ocean alkalinity enhancement; OAE). However, it must be stated, that dissolution of Olivine is always accompanied by a release of mineral dissolution products (Si, Ca, Mg, Fe, Ni and other metals). If applied in gigatons in future NET approaches, these dissolution products will increase in the environment, with currently unknown consequences for the "engineered" ecosystem. The biological sensitivity of pelagic ecosystems to OAE will likely depend on community composition, productivity and ecological interactions. Hence, this project aims to assess the effects of OAE by analyzing different domains of life (bacteria, archaea, eukarya/microalgae) of the pelagic community by using molecular approaches (e.g. tag sequencing, FISH).


You will:

  • Carry out mesocosm experiments, focusing on the effects of OAE by enhanced weathering of Olivine minerals
  • Plan and carry out molecular community analyses (e.g. tag sequencing, FISH).
  • Apply advanced multivariate statistical analyses (e.g. co-occurrence networks)


  • Master degree (or equivalent) in Aquatic Sciences or Microbiology (or related fields)
  • a strong background in Molecular Aquatic Ecology and Bioinformatics
  • strong team player skills
  • strong cooperation and communication skills in the English language

Further Information

For further information, please contact Dr. Gunnar Gerdts (; +49(4725)819-3245), Dr. Antje Wichels (; +49(4725)819-3257) or Prof. Dr Maarten Boersma (; +49(4725)819-3350).

The position is limited to 3 years. The salary will be paid in accordance with the Collective Agreement for the Public Service of the Federation (Tarifvertrag des öffentlichen Dienstes, TVöD Bund), up to salary level 13 (66%). The place of employment will be Helgoland.

All doctoral candidates will be members of AWI's postgraduate program POLMAR or another graduate school and thus benefit from a comprehensive training program and extensive support measures.

The AWI is characterised by

  • our scientific success - excellent research
  • collaboration and cooperation - intra-institute, national and international, interdisciplinary
  • opportunities to develop - on the job, aiming at other positions and beyond AWI
  • a culture of reconciling work and family - an audited and well-supported aspect of our operation
  • our outstanding research infrastructure - ships, stations, aircraft, laboratories and more
  • an international environment - everyday contacts with people from all over the world
  • having an influence - fundamental research with social and political relevance
  • flat hierarchies - facilitating freedom and responsibility
  • exciting science topics, with opportunities also in technology, administration and infrastructure

Equal opportunities are an integral part of our personnel policy. The AWI aims to increase the number of female employees and therefore strongly encourages qualified women to apply.

Disabled applicants will be given preference when equal qualifications are present.

The AWI fosters the compatibility of work and family in various ways and has received a number of awards as a result of this engagement.

We look forward to your application!

Please submit your application by December 14th 2021, exclusively online.

Reference number 21/212/G/Bio-b.

posted: 18 November 2021     Please mention EARTHWORKS when responding to this advertisement.