Carbon dioxide exchange of a larch forest after a typhoon disturbance

Tomohito Sano, Takashi Hirano, Naishen Liang, Ryuichi Hirata, Yasumi Fujinuma
2010 Forest Ecology and Management  
A typhoon event catastrophically destroyed a 45-year-old Japanese larch plantation in southern Hokkaido, northern Japan in September 2004, and about 90% of trees were blown down. Vegetation was measured to investigate its regeneration process and CO 2 flux, or net ecosystem production (NEP), was measured in 2006-2008 using an automated chamber system to investigate the effects of typhoon disturbance on the ecosystem carbon balance. Annual maximum aboveground biomass (AGB) increased from 2.7 Mg
more » ... a -1 in 2006 to 4.0 Mg ha -1 in 2007, whereas no change occurred in annual maximum leaf area index (LAI), which was 3.7 m 2 m -2 in 2006 and 3.9 m 2 m -2 in 2007. Red raspberry (Rubus idaeus) had become dominant within 2 years after the typhoon disturbance, and came to account for about 60% and 50% of AGB and LAI, respectively. In comparison with CO 2 fluxes measured by the eddy covariance technique in 2001-2003, for 4.5 months during the growing season, the sum of gross primary production (GPP) decreased on average by 739 gC m -2 (64%) after the disturbance, whereas ecosystem respiration (RE) decreased by 501 gC m -2 (51%). As a result, NEP decreased from 159 ± 57 gC m -2 to -80 ± 30 gC m -2 , which shows that the ecosystem shifted from a carbon sink to a source. Seasonal variation in RE was strongly correlated to soil temperature. The interannual variation in the seasonal trend of RE was small. Light-saturated GPP (P max ) decreased from 30-45 μmol m -2 s -1 to 8-12 μmol m -2 s -1 during the summer season through the disturbance because of large reduction in LAI.
doi:10.1016/j.foreco.2010.09.026 fatcat:knb56ajex5dk5b7rlecjyoy5ia