Russian boreal peatlands dominate the natural European methane budget

About 60% of the European wetlands are located in the European part of Russia. Nevertheless, data on methane emissions from wetlands of that area are absent. Here we present results of methane emission measurements for two climatically different years from a boreal peatland complex in European Russia. Winter fluxes were well within the range of what has been reported for the peatlands of other boreal regions before, but summer fluxes greatly exceeded the average range of 5-80 mgCH(4) m(-2) d(-1) for the circumpolar boreal zone. Half of the measured fluxes ranged between 150 and 450 mgCH(4) m (2) d (1). Extrapolation of our data to the whole boreal zone of European Russia shows that theses emissions could amount to up to 2.7 +/- 1.1 TgCH(4) a(-1), corresponding to 69% of the annual emissions from European wetlands or 33% of the total annual natural European methane emission. In 2008, climatic conditions corresponded to the long term mean, whereas the summer of 2011 was warmer and noticeably drier. Counterintuitively, these conditions led to even higher CH4 emissions, with peaks up to two times higher than the values measured in 2008. As Russian peatlands dominate the areal extend of wetlands in Europe and are characterized by very high methane fluxes to the atmosphere, it is evident, that sound European methane budgeting will only be achieved with more insight into Russian peatlands.