HR: 16:45h
AN: B44C-04    [Abstracts]
TI: Holocene Fires and Atmospheric Carbon Emissions Modeling in Eastern Canada
AU: * Carcaillet, C
EM: carcaillet@univ-montp2.fr
AF: Ecole Pratique des Hautes Etudes (CBAE, UMR5059 - CNRS), Institut de Botanique 163 rue Broussonet, Montpellier, F-34090 France
AU: Boulant, N
EM: boulant@cefe.cnrs-mop.fr
AF: Ecole Pratique des Hautes Etudes (CBAE, UMR5059 - CNRS), Institut de Botanique 163 rue Broussonet, Montpellier, F-34090 France
AU: Richard, P J
EM: Pierre.Richard@UMontreal.ca
AF: Departement de G‚ographie, Universit‚ de Montr‚al, CP 6128 succ. Centre Ville, Montr‚al, Qc H3C 3J7 Canada
AB: We modeled the atmospheric carbon released by paleofires from Quebec and Ontario, eastern Canada. The terms of the model include the biome areas, the net rate of carbon released per biome from biomass burning and the fire anomaly per ka versus present-day (0ka) deduced from charcoal series of 37 lakes. Over the Postglacial, the Taiga zone does not matches the pattern of fire history and carbon released of Boreal, Boreal Atlantic Maritime and Mixed Wood Plains zones because of different air masses influences. Our focus on 6ka and 3ka shows that the role of the Mixed Wood Plains and the Boreal Atlantic Maritime zones on the total carbon emissions by fires is negligible both at 6 and 3ka. At 6ka, the Taiga zone plays a key role, while at 3ka the Taiga and the Boreal zones display equivalent contributions to the total carbon released to the atmosphere. The role of fires at 6ka and at 0ka is similar on the total atmospheric carbon mass emission despite changes in biomass burning activity. The role of Taiga at 6ka is compensated by Boreal zone at 0ka. However, the carbon emission at 3ka is significantly higher (ca 30%) than at 6 and 0ka because of sustained high fire activity both in Taiga and Boreal zones. Long-term climatic changes affect the biomass burning activity that acts together with vegetation cover on the global carbon cycle.
DE: 3344 Paleoclimatology
DE: 0330 Geochemical cycles
DE: 0400 Biogeosciences
SC: Biogeosciences [B]
MN: 2004 AGU Fall Meeting