Methane emissions from mires in all climate-vegetation zones of West Siberia (forest steppe, subtaiga, south taiga, middle taiga, north taiga, forest tundra and tundra) were measured using a static chamber method. The observed fluxes varied considerably from small negative values in forested bogs and palsa to hundreds of mgC m −2 h −1 in ponds and wet hollows. Observed data were consolidated in the form of the empirical model of methane emissions designated as the 'standard model'. The model is based on medians of CH 4 flux distributions of eight different micro-landscape types depending on their location and estimated duration of methane emission period within the climate-vegetation zone. The current version (Bc8) of the 'standard model' estimates methane flux from West Siberia mires at 2.93 ± 0.97 TgC CH 4 yr −1 that accounts for about 2.4% of the total methane emission from all mires or 0.7% of global methane emission from all sources.

This study compares seasonal and spatial variations in methane fluxes as sources of uncertainty in regional CH 4 flux upscaling from the wetlands of West Siberia. The study examined variability in summertime CH 4 emissions from boreal peatlands, with a focus on two subtaiga fen sites in the southern part of West Siberia (Novosibirskaya oblast). We measured CH 4 flux, water table depth, air and peat temperature, pH and electric conductivity of peat water during three field campaigns in summer 2011 (9-12 July, 26-28 July and 20-21 August). Fluxes were measured with static chambers at sites chosen to represent two of the most widespread types of wetlands for this climatic zone: soligenous poor fens and topogenous fens. In both sites the water table level acts as the primary control on fluxes. For the poor fen site with good drainage, water table controls CH 4 fluxes on the seasonal scale but not on a local spatial scale; for the fen site with weak drainage and microtopographic relief, the water table controls fluxes on the local spatial scale, but does not drive seasonal variations in the flux magnitude. This difference in hydrology shows the necessity of including detailed wetland type classification schemes into large-scale modeling efforts. From these three measurement periods, we estimated the relative seasonal variation in CH 4 emissions as 8% for the fen site and 26% for the poor fen site. These results were compared to estimates of other sources of uncertainty (such as interannual variation and spatial heterogeneity) to show that quantifying seasonal variability is less critical than these other variations for an improved estimate of regional CH 4 fluxes. This research demonstrates and ranks the challenges in upscaling measured wetland CH 4 fluxes across West Siberia and can guide future field campaigns.

The methane emission from typical bog landscapes of the West Siberian subtaiga was studied in the summer-autumn of 2007-2010. The lowest specific fluxes (the median value is 0.08 mg C CH 4 /m 2 per h) were recorded from ryams (raised bogs with dwarf shrub-sphagnum associations). From the ridges of the ridge-pool complexes, the fluxes were estimated at 0.49 mg C CH 4 /m 2 per h; from the oligotrophic hollows, eutrophic bogs, floating lake mats, and mesotrophic quaking bogs, they were estimated at 2.68, 3.36, 4.53, and 4.98 mg C CH 4 /m 2 per h, respectively. The maximal flux was determined from the lakes (the median is 17.98 mg C CH 4 /m 2 per h). The regional assessment of the methane flux from the bogs of Western Siberia (2.93 Tg C CH 4 /yr) was obtained on the basis of the authors' and literature data.

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