PARENT SESSION
Oral Session #54: Vegetation: Controls on NPP, Global Climate Change. Presiding: W. Oechel.
Wednesday, August 8, 2001. 1:00 PM to 5:00 PM. Hall of Ideas G.
Modeling the carbon dynamics of a fire chronosequence in interior Alaska .
ZHUANG, QIANLAI1, MCGUIRE, DAVID2, HARDEN, JENNIFER3, O'NEILL, KATHERINE4, ROMONANVSKY, VLADIMIR5, YARIE, JOHN6, 1 2 3 4 5 6
ABSTRACT- Wildfire, a major disturbance in boreal forests, is a primary control on patterns of carbon storage and release in northern ecosystems. Fire causes the release of carbon to the atmosphere through the combustion of organic matter. Following fire, the loss of insulating moss layer and changes in the albedo of the soil surface causes permafrost to thaw and alters the rate of decomposition of dead organic matter. To simulate the successional carbon dynamics of burned black spruce ecosystems in interior Alaska, we reconfigured the hydrological dynamics of TEM to consider drainage issues, and coupled the Soil Thermal Model (STM) to TEM. We parameterized the new version of TEM-STM for a black spruce forest of LTER at Bonanza Creek Forest Experiment Station in interior Alaska. The model and parameterization were verified with soil temperatures and carbon fluxes of an old black spruce forests of BOREAS, and verified with the vegetation carbon data from survey inventory database for black spruce forests in Alaska. We then applied this version of TEM to a chronosequence of burned black spruce stands, which were 1, 3, 7, 10, 41, 80, 140, and 170 years old. The seasonal and successional patterns of simulated soil temperature, soil carbon storage, and soil respiration in 1997 compared well with measurements.
KEY WORDS: Fire disturbance, soil carbon dynamics, soil respiration, soil thermal dynamics