Annual Carbon Gas Emissions from a Boreal Peatland in Continuous Permafrost Zone, Northeast China. Issue 5 (1st February 2016) - Miao, Yuqing
Abstract : Peatland is a significant ecosystem that has accumulated one‐third of the soil carbon in boreal regions. However, the net carbon balance, particularly with current carbon emissions, remains unclear. In this study, the annual ecosystem respiration and CH4 fluxes from a peatland located in Northeast China are reported. Ecosystem respiration fluxes from the shrub‐moss‐ and Eriophorum ‐dominated communities in the peatland varied from 12 to 272 mg C m −2 h −1 during the snow‐free season, and the Eriophorum ‐dominated community emitted more CO2 . Rates of ecosystem respiration were strongly regulated by temperature and water table depth. The CH4 fluxes emitted from the peatland throughout a year varied with the type of the vegetation community during the snow‐free season. No distinct episodic CH4 efflux during the freeze–thaw cycles was observed from the shrub‐moss‐dominated community, whereas a subtle pulse of CH4 was found in the Eriophorum ‐dominated community. The annual ecosystem respiration and CH4 fluxes from the peatland were 356 and 1.51 g C m −2 per year, respectively. The contributions of CO2 and CH4 fluxes from the snowy season to annual emissions were much lower than those found in other boreal peatlands, whereas 24% of the annual methane flux was emitted during the freeze–thaw cycles. The results highlight the importance of gaseous carbon efflux in the estimation of carbon flux from peatlands, as well as the contribution of carbon efflux during the snow‐covered season. Abstract : The annual carbon greenhouse gas emission from a peatland in a continuous permafrost zone in Northeast China was studied. The Eriophorum community emitted more CH4 and less CO2 than the shrub‐moss community. CH4 fluxes during the freeze–thaw cycles accounted for an important part of annual CH4 emissions.