HR: 13:40h
AN: B12E-01 INVITED     [PDF]
TI: Fire and Carbon in Canadian Forests
AU: Amiro, B D
EM: bamiro@nrcan.gc.ca
AF: Canadian Forest Service, Northern Forestry Centre 5320 - 122 Street, Edmonton, AB T6H 3S5 Canada
AU: Flannigan, M D
EM: mflannig@nrcan.gc.ca
AF: Canadian Forest Service, Great Lakes Forestry Centre 1219 Queen Street E., Sault Ste. Marie, ON P6A 2E5 Canada
AU: * Stocks, B J
EM: bstocks@nrcan.gc.ca
AF: Canadian Forest Service, Great Lakes Forestry Centre 1219 Queen Street E., Sault Ste. Marie, ON P6A 2E5 Canada
AB: Fire is the major stand-renewing agent in Canadian forests, affecting carbon sources and sinks. On average over the past 40 years, about 27 Tg carbon have been emitted directly through combustion of Canadian forest fires annually, but in some years, this can be over 100 Tg carbon. The overall impact is much greater because fire-killed vegetation decomposes and releases carbon through heterotrophic respiration. In addition, very young successional vegetation that replaces the burned forest is usually a weaker carbon sink until the forest canopy develops. The magnitude of these post-fire effects has not been well quantified, but models suggest that it is of a similar magnitude to the direct combustion emissions. Post-fire carbon fluxes are being measured using eddy covariance as part of FLUXNET-Canada on a chronosequence of burned forests. These long-term measurements, in conjunction with short-term aircraft measurements and modelling are helping to reduce the uncertainty in our estimates of the effect of fire on the forest carbon balance. The impact of fire on forest carbon is expected to become more important in the future since global circulation models and regional climate models suggest that the area burned could double in Canada under a 3xCO2 climate. This will be caused by warmer and drier conditions throughout much of the country. Although climate is a main driver of fire, landscape and fuel changes also need to be considered. Ongoing research is aimed at evaluating the potential to mitigate fire through landscape modifications and other fire management options. However it is most likely that we will need to adapt to the economic, social and ecological impacts of fire in a changing climate.
DE: 1615 Biogeochemical processes (4805)
DE: 3322 Land/atmosphere interactions
SC: Biogeosciences [B]
MN: 2003 Fall Meeting