Our research focuses on decomposer organisms, primarily fungi, and is driven by a demand to increase understanding of organic matter turnover in ecosystems.
Respiration measurements of decomposing pine needles colonized by Mycena epipterygia (photo by Johanna Boberg).
The rate limiting factor for degradation of organic macromolecules is the activity of extracellular enzymes, produced by micro-organisms. In order to understand how the production of degrading enzymes is regulated by abiotic and biotic factors in the environment, we need a better knowledge on the identity, genetics and basic eco-physiology of the microorganisms that produce enzymes.
With the ultimate aim to better understand factors regulating carbon sequestration, nutrient circulation and ecosystem production, we study how microorganisms interact with wood, litter components, crop residues and soil organic matter. Genome sequencing and expression analyses reveal mechanisms behind polymer degradation in different substrates. The unique capacity of fungi to transport resources in their mycelia has important implications for decomposition. In boreal and arctic ecosystems, we investigate the potential of ectomycorrhizal fungi to transport carbohydrates from living roots to power degradation of recalcitrant organic matter in soils. Another line of research focuses on degradation of crop residues in relation to crop protection and sustainable food production in developing countries.
Decomposition processes are investigated in laboratory microcosms as well as directly in the field. Our methods include tracer isotopes (13C and 15N), 14C dating, enzyme assays and molecular community analyses by 454-sequencing and qPCR, as well as genome and gene expression analyses.