SREL Reprint #3736

The effect of rapid development on soil CO2 efflux in a cellulosic biofuel stand

Nicholas Wright-Osment1, Gregory Starr1, Doug P. Aubrey2,3, Benjamin M. Rau4,
and Christina L. Staudhammer1

1Department of Biological Sciences, University of Alabama, Tuscaloosa, AL 35487, USA
2Savannah River Ecology Laboratory, University of Georgia, Aiken, SC 29802, USA
3Warnell School of Forestry and Natural Resources, University of Georgia, Athens, GA 30602, USA
4USDA Forest Service Northern Research Station, Parsons, WV 26287, USA

Abstract: As awareness of climate change increases, the need for carbon neutral fuel sources is growing. Lignocellulosic biofuel derived from pine trees has been suggested as one potential energy source; however, it requires more research before its efficacy for climate change mitigation can be determined. Due to the large share of forest carbon held in soils and the extensive area of pine plantations in the southeast U.S., a better understanding of plantation soil carbon dynamics is critical for biofuel carbon accounting. This study evaluated the effects of canopy development and productivity on soil CO2 efflux, a proxy for soil respiration (Rs), in an intensively managed loblolly pine (Pinus taeda) stand over a period from May 2015 to December 2019. We found that leaf area index (LAI) and gross ecosystem production (GEP), as well as meteorological variables, had significant effects on Rs, but that both overall Rs and soil carbon pools did not increase over the course of the study. We thus hypothesize that GEP and LAI had intra-annual effects on Rs, and that the lack of change in Rs is the result of an increase in autotrophic respiration (Ra) that offset a decrease in decomposition of the previous stand’s organic matter.

Keywords: forest productivity; leaf area index; gross primary production; carbon; Pinus taeda

SREL Reprint #3736

Wright-Osment, N., G. Starr, D. P. Aubrey, B. M. Rau, and C. L. Staudhammer. 2023. The effect of rapid development on soil CO2 efflux in a cellulosic biofuel stand. Forests 14(258).

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