Climate change in Arctic ecosystems fosters permafrost thaw and makes massive amounts of ancient soil organic carbon ( OC ) available to microbial breakdown. However, fractions of the organic matter ( OM ) may be protected from rapid decomposition by their association with minerals. Little is known about the effects of mineral‐organic associations ( MOA ) on the microbial accessibility of OM in permafrost soils and it is not c...

Terrestrial ecosystems in northern high latitudes exchange large amounts of methane (CH 4 ) with the atmosphere. Climate warming could have a great impact on CH 4 exchange, in particular in regions where degradation of permafrost is induced. In order to improve the understanding of the present and future methane dynamics in permafrost regions, we studied CH 4 fluxes of typical landscape structures in a small catchment in the f...

Boreal permafrost soils store large amounts of organic carbon (OC). Parts of this carbon (C) might be black carbon (BC) generated during vegetation fires. Rising temperature and permafrost degradation is expected to have different consequences for OC and BC, because BC is considered to be a refractory subfraction of soil organic matter. To get some insight into stocks, variability, and characteristics of BC in permafrost soils...

During winter and early spring, evergreen boreal conifers are severely stressed because light energy cannot be used when photosynthesis is pre‐empted by low ambient temperatures. To study photosynthetic performance dynamics in a severe boreal climate, seasonal changes in photosynthetic pigments, chloroplast proteins and photochemical efficiency were studied in a Scots pine forest near Zotino, Central Siberia. In winter, downre...

The timing of the commencement of photosynthesis ( P * ) in spring is an important determinant of growing‐season length and thus of the productivity of boreal forests. Although controlled experiments have shed light on environmental mechanisms triggering release from photoinhibition after winter, quantitative research for trees growing naturally in the field is scarce. In this study, we investigated the environmental cues init...