SREL Reprint #3454

Intermediate time scale response of atmospheric CO2 following prescribed fire in a longleaf pine forest

B. Viner1, M. Parker1, G. Maze1, P. Varnedoe2, M. Leclerc3, G. Starr4, D. Aubrey5,6, G. Zhang3,
and H. Duarte3

1Savannah River National Laboratory, Aiken, South Carolina, USA
2United States Forest Service–Savannah River, New Ellenton, South Carolina, USA
3College of Agricultural and Environmental Science, University of Georgia, Griffin, Georgia, USA
4Department of Biological Sciences, University of Alabama, Tuscaloosa, Alabama, USA
5Savannah River Ecology Laboratory, University of Georgia, Aiken, South Carolina, USA
6Warnell School of Forestry and Natural Resources, University of Georgia, Athens, Georgia, USA

Abstract: Fire plays an essential role in maintaining the structure and function of longleaf pine ecosystems. While the effects of fire on carbon cycle have been measured in previous studies for short periods during a burn and for multiyear periods following the burn, information on how carbon cycle is influenced by such changes over the span of a few weeks to months has yet to be quantified. We have analyzed high-frequency measurements of CO2 concentration and flux, as well as associated micrometeorological variables, at three levels of the tall Aiken AmeriFlux tower during and after a prescribed burn. Measurements of the CO2 concentration and vertical fluxes were examined as well as calculated net ecosystem exchange (NEE) for periods prior to and after the burn. Large spikes in both CO2 concentration and CO2 flux during the fire and increases in atmospheric CO2 concentration and reduced CO2 flux were observed for several weeks following the burn, particularly below the forest canopy. Both CO2 measurements and NEE were found to return to their preburn states within 60–90 days following the burn when no statistical significance was found between preburn and postburn NEE. This study examines the micrometeorological conditions during a low-intensity prescribed burn and its short-term effects on local CO2 dynamics in a forested environment by identifying observable impacts on local measurements of atmospheric CO2 concentration and fluxes.

SREL Reprint #3454

Viner, B., M. Parker, G. Maze, P. Varnedoe, M. Leclerc, G. Starr, D. P. Aubrey, G. Zhang, and H. Duarte. 2016. Intermediate time scale response of atmospheric CO2 following prescribed fire in a longleaf pine forest. Journal of Geophysical Research: Biogeosciences 121: 2745-2760.

This information was provided by the University of Georgia's Savannah River Ecology Laboratory (srel.uga.edu).