2004 Volume 38 Issue 2 Pages 57-65
Measurements of CH4 emission and soil temperature on a small bog margin at 1,900 m elevation in the Tateyama Midagahara (36°34'N, 137°33'E) were made on a monthly basis from June to November during 1997-1998. The CH4 fluxes determined by a static chamber technique ranged from 0.31 to 270 mg CH4-Cm-2day-1 and were related to peat temperature. There was a positive relationship between precipitation and CH4 flux: larger precipitation led to larger fluxes. The CO2 flux ranged from 0.026 to 2.8 g CO2-C m-2day-1 and strongly correlated with CH4 flux. Determinations of carbon isotopic compositions in CH4 and CO2 revealed δ13C values of -60.9 to -72.9‰ and -19.2 to -24.9‰, respectively. Comparision of δ13C signatures between CH4 and CO2 suggested that CH4 oxidation is not an important overall control on CH4 emission and indicated that most of the CH4 was formed by mixture of acetate fermentation and CO2 reduction pathways.
