Due to the growing concern over increasing atmospheric CO2 concentrations, it has become increasingly important to understand the influence forest practices have on the global carbon cycle. The thinning of loblolly pine (Pinus taeda) plantations in the Southeastern United States is a common silvicultural practice and has great potential to influence carbon fluxes. In order to quantify the effects of thinning on CO2 efflux (Ec), measurements were taken monthly for 1 year, following the thinning of a 22-year-old loblolly pine stand. Soil moisture and temperature were measured concurrently with respiration. Ec measurements were taken at positions adjacent to trees and new stumps, as well as 1.22 m away. Ec appeared to exhibit a slight increase in thinned stands; however, all significant differences were explained by the higher temperatures in thinned stands. This suggests that other than through increasing temperature, thinning does not significantly affect soil Ec , as gains and losses in respiration from many altered biological processes may cancel each other out.
Selig, M.F.; Seiler, J.R. 2004. Soil CO2 Efflux Trends Following the Thinning of a 22-Year-Old Loblolly Pine Plantation on the Piedmont of Virginia. Gen. Tech. Rep. SRS–71. Asheville, NC: U.S. Department of Agriculture, Forest Service, Southern Research Station. pp. 469-472