|Prior, Stephen - Steve|
|Rogers Jr, Hugo|
Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 1/15/1999
Publication Date: N/A
Citation: Saxon, M.E., Dute, R.R., Pritchard, S.G., Prior, S.A., Mitchell, R.J., Davis, M.A., and Rogers, H.H. 1999. Species within a regenerating longleaf pine community respond differently to elevated atmospheric CO2.The Journal of the Alabama Academy of Science 70(1-2):19.
Technical Abstract: Atmospheric CO2 levels are rising and are predicted to double in the next century, due mostly to fossil fuel consumption. Since plants utilize CO2 as a substrate for photosynthesis, changes in atmospheric CO2 levels can potentially affect the growth and productivity of plants. Our study's goal was to assess how increased CO2 would affect plants at the individual species and community levels. Species were chosen to represent a model regenerating longleaf pine community like that found in the Coastal Plain region of the southeastern U. S. The samples were grown in outdoor experimental plots using open-top chambers to deliver either ambient atmospheric CO2 concentrations, 365 ppm, or elevated, 720 ppm. After a four month period, photosynthetic activity and plant morphological characteristics such as number of leaves, stem height, and leaf dry weight, were measured. Longleaf pine (Pinus palustris) showed significant increases in all but one morphological category when grown under elevated OC2. Sand post oak (Quercus margaretta), rattlebox- a legume (Crotalaria rotundifolia), and a C4 wiregrass (Aristida stricta), all showed no significant morphological or growth changes between the two treatments. Photosynthesis measurements made with a LICOR 6400 portable photosynthesis system showed no significant differences between CO2 treatments for wiregrass, oak or rattlebox. Pine, however, showed an increase in photosynthesis in the elevated CO2 plants. These preliminary results indicate that the pine responds positively to increased CO2 while the other species show limited response in these particular measurements.