Changes in fluxes of carbon dioxide and methane caused by fire in Siberian boreal forest with continuous permafrost

New paper by Köster et al., 2018 is dealing with the long-term effects of fires on the fluxes of two main C-based GHGs (CO2 and CH4) in boreal coniferous forest areas in central Siberia with underlying permafrost.

The results of the study indicate that fire significantly affected the fluxes of CO2, and the impact of fire lasted much longer than expected based on previous studies. There was a significant decrease in soil CO2 efflux shortly after the fire, but over time the emissions started to increase and this increase continued for more than 50 years after the fire. The effect of fire on the CH4 flux was not significant in Siberian boreal forest with a permafrost base, but all the studied areas acted as a CH4 sink. There was a clear negative correlation between CO2 emissions and depth of the active layer, while CH4 fluxes were not influenced by it. The results also confirmed that the role of recovering vegetation in CO2 emissions is significant as the main factors driving the CO2 flux were the biomass of birch and alder trees, and the biomass of the vascular plants in the ground vegetation.

Reindeer grazing alter soil fungal community structure and litter decomposition related enzyme activities in boreal coniferous forests in Finnish Lapland

New paper by Santalahti et al., 2018 is the first to describe detailed fungal community structure using a 454-pyrosequencing analysis in reindeer grazed and nongrazed
sites in northern boreal coniferous forest soils.

The results of the study indicate that reindeer grazing alters significantly the soil fungal community structures and the abundance of Ascomycota, as well as certain fungal genera and species. Within longer time scales, grazing may affect litter decomposition through changes in fungal community structure and enzyme activities in the northern boreal forest soils.