HR: 0800h
AN: B51D-0242    [Abstracts]
TI: Inter-annual variation in the response of Pinus taeda tree growth to long term Free Air Carbon dioxide Enrichment (FACE)
AU: Moore, D J
EM: djmoore1@express.cites.uiuc.edu
AF: Program in Ecology and Evolutionary Biology, University of Illinois at Urbana - Champaign, Urbana, IL 61801 United States
AU: Aref, S
EM: saref@pop.vt.edu
AF: Department of Statistics, University of Illinois at Urbana - Champaign, Urbana, IL 61801 United States
AU: Ho, R M
EM: mho@psych.mcgill.ca
AF: Department of Statistics, University of Illinois at Urbana - Champaign, Urbana, IL 61801 United States
AU: Pippen, J S
EM: jspippen@acpub.duke.edu
AF: Nicholas School of the Environment and Earth Sciences, Duke University, Durham, NC 27708 United States
AU: Hamilton, J
EM: jspippen@acpub.duke.edu
AF: Department of Biology, Ithaca College, Ithaca, NY 14850
AU: * De Lucia, E H
EM: delucia@uiuc.edu
AF: Department of Plant Biology, University of Illinois at Urbana - Champaign, Urbana, IL 61801 United States
AB: Rising carbon dioxide is predicted to increase forest productivity, though the duration of the response and how it might be altered by annual variation in rainfall and temperature are not well understood. For eight years we measured the basal area of trees exposed to Free Air Carbon-dioxide Enrichment (FACE) in a rapidly growing Pinus taeda plantation and used these measurements to estimate monthly and annual growth. We coupled these measurements with a mathematical model to estimate the start and end of growth in each year. Elevated carbon dioxide increased the basal area increment (BAI) of trees by 13 to 27 percent. Exposure to elevated carbon dioxide increased the growth rate but not the duration of the growing season in most years. With the exception of one year following an extreme drought and a severe ice storm, BAI was positively correlated with the amount of rainfall during the growing season. The inter-annual variation in the relative enhancement of BAI caused by elevated carbon dioxide was strongly related to the combination of temperature and rainfall during the growing season. There was no evidence of a systematic reduction in the stimulation of growth during the first eight years of this experiment, suggesting that hypothesized limitation of the carbon dioxide response caused by nitrogen availability has yet to occur.
UR: http://www.life.uiuc.edu/delucia/index.htm
DE: 0414 Biogeochemical cycles, processes, and modeling (0412, 0793, 1615, 4805, 4912)
DE: 0428 Carbon cycling (4806)
DE: 0439 Ecosystems, structure and dynamics (4815)
DE: 0476 Plant ecology (1851)
SC: Biogeosciences [B]
MN: Fall Meeting 2005