PhD fellowship in greenhouse gases, forest soils and biogeochemistry

The section of Forest & Landscapce Ecology at Deparment of Geoscience and Natural Resource Management (IGN) invites applicants for a PhD fellowship in soil N2O fluxes and processes in temperate forest ecosystems. The project is part of the research project ‘Predicting the climate change mitigation potential of new forest landscapes in Denmark’, which is financed by Independent Research Fund Denmark.

Start date is (expected to be) December 1st 2026 or as soon as possible thereafter.

The project

Forests are key ecosystems in Denmark for sequestering atmospheric CO2, conserving water resources, and supporting biodiversity. As Denmark aims to reach climate neutrality by 2045, afforestation is a central component of the Green Tripartite to achieve this goal. A total of 250 000 ha of new forests will be planted over the next two decades, profoundly transforming the Danish landscape.

To reach these ambitious goals we must understand forest ecosystem functioning, particularly balancing carbon and nitrogen cycling, in the transition from agriculture to forest. The combined benefits of afforestation for climate change and N (i.e., reduced GHG emissions as well as decreased N pollution) vary with tree species, climate and soil conditions, and management practices. In Denmark especially, legacy effects of agricultural management (e.g., fertilization, liming, soil disturbance and homogenization) have created a novel state of soil N cycling, in which forests may grow faster and sequester more carbon (C). However, this may increase nitrogen leaching and soil N2O emissions, partially offsetting enhanced C sequestration. Thus, large uncertainties exist regarding changes in the nitrogen balance, particularly losses of gaseous N, along land cover transitions, partly due to limited focus on N fluxes compared to C fluxes in new forests.

About the PhD position

The PhD position aims to fill this knowledge gap by addressing how tree species, soil types and forest management practices impact net fluxes of greenhouse gases from the forest soil, focusing primarily on the strong greenhouse gas N2O, but also including CH4 and CO2. The project involves working with existing unpublished datasets from Danish forests, fieldwork at selected forest sites in Denmark with different tree species (conifers and broadleaves) and land use legacies (agriculture and forest), and doing laboratory mesocosm experiments. You will be measuring greenhouse gas fluxes using advanced methods for gas detection in the field and laboratory, including stable isotope techniques, and deploy mathematical and statistical tools to analyze the data.

Your key responsibilities in the PhD project are

• Analyse existing unpublished data sets on N2O and other greenhouse gases for Danish forests
• Plan and execute field work in Denmark during your PhD project
• Plan and execute laboratory studies of soil greenhouse gas dynamics
• Attend PhD courses (in total of 30 ECTS)
• Write scientific articles and your PhD thesis
• Disseminate your research at the institute and conferences
• Research visit to Land-CRAFT at Aarhus University
• Work for the department (teaching and supervision of students)

Who are we looking for?

We are looking for candidates within the field(s) soil, biogeochemistry or environmental science and it is expected that you are experienced in data analyses and use of R or similar programming language. Fieldwork experience is required and it is an advantage that you have demonstrated prior knowledge of handling advanced equipment for greenhouse gas studies. Applicants must be fluent in both written and spoken English to a level sufficiently high for communication and dissemination at an academic level.

Our group and research- and what do we offer?

As a PhD student, you will be enrolled at SCIENCE PhD school at University of Copenhagen and your main workplace will be at IGN in Copenhagen where you will be part of the Biogeochemistry research group. We offer creative and stimulating working conditions in dynamic and international research environment. Our research group is focused on soil and ecosystem biogeochemistry in forests and nature, including grasslands and wetlands. We use field and laboratory experiments with an emphasis and measure pools and fluxes of water, carbon, nitrogen and other nutrients. We have an advanced laboratory for chemical analyses soil, water and biomass and an up-to-date portfolio of analyzers and chamber systems for greenhouse gas studies. 

Dr. Jesper Riis Christiansen (IGN, jrc@ign.ku.dk) will be your main supervisor. Jesper is working with N2O and CH4 fluxes in forest and wetland soils and investigates how nature restoration (afforestation and rewetting) affect the soil processes that produce these greenhouse gases. Academic co-supervision will be provided by Prof. Per Gundersen (IGN) and Prof. Klaus Butterbach-Bahl (Aarhus University) at Land-CRAFT in Aarhus where you are expected to spend part of your time for laboratory experiments.

The PhD programme

You can undertake the PhD programme as a three year full-time study within the framework of the regular PhD programme (5+3 scheme), if you already have an education equivalent to a relevant Danish master’s degree.

Getting into a position on the regular PhD programme

Qualifications needed for the regular programme
To be eligible for the regular PhD programme, you must have completed a degree programme, equivalent to a Danish master’s degree (180 ECTS/3 FTE BSc + 120 ECTS/2 FTE MSc) related to the subject area of the project, e.g. [relevant educations]. For information of eligibility of completed programmes, see General assessments for specific countries and Assessment database.

Terms of employment in the regular programme
Employment as PhD fellow is full time and for maximum 3 years.

Employment is conditional upon your successful enrolment as a PhD student at the PhD School at the SCIENCE, University of Copenhagen. This requires submission and acceptance of an application for the specific project formulated by the applicant.

Terms of appointment and payment accord to the agreement between the Danish Ministry of Taxation and The Danish Confederation of Professional Associations on Academics in the State. The position is covered by the Protocol on Job Structure.

Application and Assessment Procedure

 Your application including all attachments must be in English and submitted electronically by clicking APPLY NOW below.

Please include: 

1. Motivated letter of application (max. one page)
2. Brief description of possible research ideas and relevant methods (max. one page, cited literature excluded) related to this specific project
3. Curriculum vitae including information about your education, experience, language skills and other skills relevant for the position
4. Original diplomas for Bachelor or Master and transcript of records in the original language, including an authorized English translation if issued in another language than English or Danish. If not completed, a certified/signed copy of a recent transcript of records or a written statement from the institution or supervisor is accepted.
5. Publication list (if possible)
6. Reference letters (if available)

Application deadline:

The deadline for applications is 16 August 2026, 23:59 GMT +2.

We reserve the right not to consider material received after the deadline, and not to consider applications that do not live up to the abovementioned requirements.

The further process
After deadline, a number of applicants will be selected for academic assessment by an unbiased expert assessor. You are notified whether you will be passed for assessment.

The assessor will assess the qualifications and experience of the shortlisted applicants with respect to the above-mentioned research area, techniques, skills and other requirements. The assessor will conclude whether each applicant is qualified and, if so, for which of the two models. The assessed applicants will have the opportunity to comment on their assessment. You can read about the recruitment process at https://employment.ku.dk/faculty/recruitment-process/.

Interviews with selected candidates are expected to be held in week 38.

Questions
For specific information about the PhD fellowship, please contact the principal supervisor.

General information about PhD study at the Faculty of SCIENCE is available at the PhD School’s website: https://www.science.ku.dk/phd/.

The University of Copenhagen wishes to reflect the surrounding community and invites all regardless of personal background to apply for the position.