Our team members Prof. Jukka Pumpanen (University of Eastern Finland) and Dr. Kajar Köster (University of Helsinki) are members of the Management Committee (country representatives) of the new COST Action CA18135, Fire in the Earth System: Science & Society (FIRElinks).

Dr Egle Köster (University of Helsinki) and Ms Christine Ribeiro-Kumara (University of Helsinki) are acting as Management Committee Substitutes.

FIRElinks will develop the EU-spanning network of scientists and practitioners involved in forest fire research and land management with backgrounds such as fire dynamics, fire risk management, fire effects on vegetation, fauna, soil and water, and socio-economic, historical, geographical, political perception and land management approaches. It will connect communities from different scientific and geographic backgrounds, allowing the discussion of different experiences and the emergence of new approaches to fire research.

The main aim of FIRElinks is to power synergistic collaborations between European research groups and stakeholders with the objective to synthesise the existing knowledge and expertise, and to define a concerted research agenda which promotes an integrated approach to create fire-resilient landscapes, taking into account biological, biochemical and-physical, but also socio-economic, historical, geographical, sociological, perception and policy constraints. This is an urgent societal need due to expected further intensification and geographical spreading of wildfire regimes under Global Change.

New paper by Aaltonen et al., 2019 determines how heterotrophic soil respiration (Rh), originating from the decomposition of SOM, and the Q10 of this process vary between different depths over the years following a forest fire in permafrost-affected soils. How the microbial biomass and qCO2 are affected by the fire, and what are the most important factors affecting the Q10 of SOM decomposition.

The results indicate that forest fires may facilitate the decomposition of permafrost SOM by increasing the active layer depth, but on the same time fire increased the temperature sensitivity of decomposition. The SOM in the permafrost surface was less temperature sensitive than the SOM in the soil surface. The post-fire decreases in ground vegetation were reflected in the SOM temperature sensitivity shortly after fire but seemed to return to original levels with forest succession.

The fire also increased the microbial qCO2, and these changes partly explain the lack of significant decrease in heterotrophic soil respiration after fire, as the microbes may use more C for respiration in the recently burned areas compared with the older areas. Even though fires increased the active layer depth, the decrease in SOM quality caused by fire may limit the decomposition rate to some degree.