Plant Physiological Ecology & Biogeochemistry

The focus of the Plant Physiological Ecology & Biogeochemistry research group is on climate change effects and anthropogenic impact on organisms, plant physiological and biogeochemical processes in natural and semi-natural ecosystems, mainly in the temperate and arctic zone. For more details regarding potential projects, internship etc., please see below, and feel free to contact Anders Michelsen.  


Group members

Professor Anders Michelsen (Group leader)

Post doc Signe Lett

Post doc Marianne Koranda 

PhD Student Laura Helene Rasmussen

PhD Student Emily Pickering Pedersen

MSc Students: 

Emil Sherman Andersen, Anne Marie Stevnsvig, Else Pedersen,

Elisabeth Larsen Kolstad, Julie Pedersen Festersen,

Kristine Skov, Maj Sofie Paornak D Christensen,

Simone Windfeldt-Schmidt, Frederik Grande Zimmermann,

Agnieszka Rzepczynska, Anna Polaskova, Maya Anne Nissen Olsen




The fields of research are within general and physiological ecology in terrestrial systems, including interactions between the ecosystem components, and the biodiversity of soil organisms and plants. Major approaches include investigation of plant physiological and biogeochemical responses to natural environmental variation and to global and regional environmental changes and disturbances (e.g. climate change, UV-B radiation and land use). We also study the interactions between aboveground processes such as photosynthesis, the relation to tissue chemistry, and to belowground processes, such as nutrient mineralisation and uptake by plants. The main approach of the research is experimental and generally has a process as well as an organism/population component. It spans over a hierarchy of temporal and spatial levels such as studies of

• use of stable isotopes in ecology

• gas exchange at leaf and whole plant level

• nutrient mineralisation, plant nutrient uptake and soil-microbe-plant-interactions
• nitrogen flow and carbon cycling, at community, ecosystem and landscape level

The research takes place in arctic and temperate ecosystem types. The group is using the facilities in the Ecological-Chemical Laboratory, the Isotope Ratio Mass Spectrometry and the Ecophysiology Laboratory. Field work takes place in Denmark, Sweden (Abisko),  Greenland (Zackenberg, Disko), and elsewhere.  


Current externally funded research projects include


Nitrogen fixation as a key function in contrasting ecosystems: Climatic and molecular controls (2016-2019)

• CENPERM -Center for Permafrost (2012-2022)



Current and future M.Sc/PhD/post doc projects may address questions as

• Does permafrost thaw lead to enhanced nutrient availability and plant N uptake?
• How far does ammonia emission from farms affect plants and sensitive ecosystems?
• Does climate change affect microbial and plant uptake of nitrogen?
• What is the role of ericoid and ectomycorrhizal fungi for carbon balance in northern ecosystems?
• Will arctic and danish heath ecosystems be future sources or sinks for CO2?
• Is more methane emitted from plants, soil and litter when temperatures increase? 
• To which extent does N2 fixation by microorganisms associated with plants lead to nitrogen enrichment in other ecosystem compartments?


The Ecological-Chemical Laboratory 

The Ecological-Chemical Laboratory carries out high precision physical and chemical analyses of soils, plants, gases and liquids. The laboratory is fully updated in analytical equipment and takes on analytical tasks for the scientific staff at the Dept. of Biology as well as for external reseachers. For instance we analyze:

Plant species composition
Plant biomass
Elements as C,N, P and heavy metals in soil, plants and liquids
Secondary metabolites as tannins and flavonoids
15N og 13C natural abundance and enrichment
Photosynthesis with Licor 6400XT
CH4, CO2 and BVOC
Microbial biomass CNP
Ergosterol, PLFA, Biolog plates
Screening for mycorrhiza fungi

The analytical equipment includes:

Hitachi U-2000 and U-2010 Spectrophotometers
Shimadzu Total Organic Carbon Analyzer TOC/TN
Perkin Elmer Atomic Absorption Spectrophotometer
Shimadzu GC-17A Gas Chromatograph
Fiastar 5000 Flow Analyzer
LECO TruSpec Carbon Nitrogen Determinator 
NIR Spectrometer
Eltra CS 500 Total Carbon Determinator
Aquatec 5400 Analyzer
EuroVector Elemental Analyzer EA3028-HT
Micromass IsoPrime Isotope Ratio Mass Spectrometre
Agilent GC/MS with thermal desorption
Picarro isotopic greenhouse gas analyser