Abstract
Peat wetlands are considered to be the major sources of greenhouse gases. Many studies have been con-ducted to evaluate quantitatively greenhouse gases produc-tion and consumption in peat soils, however, only limited information on dynamics of greenhouse gases in peatland forest soils. In this study, emission, production, and con-sumption of greenhouse gases such as CO2, CH4, and N2O were investigated at a soil profile in the peatland forest by combining techniques of a closed-chamber method, annual monitoring of soil gas concentrations in the unsaturated zone, and laboratory measurements on water retention and gas diffusivity for soil core samples. Results show that the annual amounts of 725 g CO2-C m−2 were emitted from the soil surface and approximately 90% of the CO2 was produced at the depth interval less than 10 cm. On the other hand, the soil profile acted as a CH4 sink and the annual amounts of 0.47 g CH4-C m−2 were oxidized （consumed) within the 0–10 cm depth interval. For the dynamics of N2O, the annual amounts of 0.249 g N2O-N m−2 were emitted from the surface and both production and consumption occurred at each depth interval above the water table. Especially, the production and consumption of N2O was significant at the 22-cm depth from the surface. It was also revealed that the N2O was produced / consumed markedly even during the snowfall and snowmelt periods differing from the CO2 and CH4.
