To examine the effects of soil warming on carbon dynamics in the wetland ecosystem

a field-warming experiment was conducted under flooded and regular conditions in a typical meadow﹝Calamagrostis angustifolia(TMC) wetland﹞of the Sanjiang Plain

Northeastern China.Electrical cables were used to simulate soil warming.Warming caused significant increases in aboveground biomass on most measuring dates

accounting for 85.12% and 49.37% more than the control under the two water conditions

respectively.Meanwhile

the root biomass also increased by 43.27% and 54.39%

respectively.Elevated temperature tended to improve soil nitrogen availability through the growing season

which was significantly correlated to the increase of aboveground biomass and root biomass.Compared to control

CO2 andCH4 fluxes of the average growing season increased by 30.55% and 31.39% respectively

and were positively correlated with 5 cm soil temperature.However

flood condition significantly reduced the aboveground biomass while increased the root biomass.However

it had no significant effect on soil NH4-N contents and CO2 and CH4 fluxes.The results indicated that soil warming would have direct effects on the fluxes of CO2 and CH4 and indirect effects on the biomass accumulation of C.angustifolia through improving soil NH4-N availability in TMC wetland ecosystem.However

little interaction between carbon sequestration and emission processes was found under soil warming conditions.