Temporal and spatial variation of soil CO/CH fluxes in two cool-temperate forests in Japan

Sun, L.*; Liang, N.*; Hirano, Takashi*; Takahashi, Yoshiyuki*; Teramoto, Munemasa*; Takagi, Kentaro*; Kondo, Toshiaki*; Koarashi, Jun   ; Atarashi-Andoh, Mariko  ; Ide, Reiko*; Zhao, X.*; Ishida, Sachinobu*; Takagi, Masahiro*; Yazaki, Tomotsugu*

To investigate soil CO/CH fluxes, we installed multi-channel automated chamber measurement systems in two cool-temperate forests of Tomakomai (natural recovered forest following the typhoon in 2004) of Hakkaido and Fuji-Hokuroku (65-year-old larch plantation) of central Japan. Soil carbon fluxes were continuously measured at hourly and two-hour intervals during snow-free season. In both forests, soil CO/CH fluxes showed high seasonal variation. Soil respiration increased exponentially with changing in soil temperature, whereas soil CH uptake was negatively correlated with soil moisture. Though both the soil temperature and moisture were not significant difference between two forests, we found significant larger soil respiration as well as CH absorption in Fuji-Hokuroku larch forest as compared with that of Tomakomai natural forest probably due to the higher root biomass and soil organic carbon.