Composition and Chemistry
Seasonal and decadal patterns of soil carbon uptake and emission along an age sequence of burned black spruce stands in interior Alaska
Article first published online: 15 JAN 2003
Copyright 2003 by the American Geophysical Union.
Journal of Geophysical Research: Atmospheres (1984–2012)
Volume 108, Issue D1, pages FFR 11-1–FFR 11-15, 16 January 2003
How to Cite
Seasonal and decadal patterns of soil carbon uptake and emission along an age sequence of burned black spruce stands in interior Alaska, J. Geophys. Res., 108(D1), 8155, doi:10.1029/2001JD000443, 2003., , and ,
- Issue published online: 15 JAN 2003
- Article first published online: 15 JAN 2003
- Manuscript Accepted: 27 OCT 2001
- Manuscript Revised: 25 OCT 2001
- Manuscript Received: 6 FEB 2001
- mass balance model
 Postfire changes in the local energy balance and soil chemistry may significantly alter rates of carbon turnover in organic-rich soils of boreal forests. This study combines field measurements of soil carbon uptake and emission along a 140-year chronosequence of burned black spruce stands to evaluate the timescales over which these disturbance effects operate. Soil CO2 efflux increased as a function of stand age at a mean rate of 0.12 Mg C ha−1 yr−2 up to a maximum of 2.2 Mg C ha−1 yr−1 in the 140-year-old stand. During this same time period, organic soil horizons sequestered carbon and nitrogen at rates of 0.28–0.54 and 0.0076 Mg N ha−1 yr−1, respectively. A mass balance model based on field measurements suggests that postfire changes in root and microbial respiration caused these soils to function as a net source of carbon for 7–15 years after fire, releasing between 1.8 and 11.0 Mg C ha−1 to the atmosphere (12.4–12.6% of total soil organic matter). These estimates are on the same order of magnitude as carbon losses during combustion and suggest that current models may underestimate the effect of fire on carbon emissions by a factor of 2.