Article,
A Quantitative-Analysis of Dark Respiration and Carbon Content as Factors in the Growth-Response of Plants to Elevated CO<sub>2</sub>
Aust. J. Bot., 40 (5): 501--513 (Jan 1, 1992)
Abstract
<P>An analysis of elevated CO<sub>2</sub> effects (2-4 times ambient) on dark respiration rate and carbon content was undertaken for a wide range of plant species, using both published reports and new data. On average, leaf respiration per unit leaf area was slightly higher for plants grown at high CO<sub>2</sub> (16\%), whereas a small decrease was found when respiration was expressed on a leaf weight basis (14\%). For the few data on root respiration, no significant change due to high CO<sub>2</sub> could be detected. Carbon content of leaves and stem showed a small increase (1.2 and 1.7\% respectively), whereas C-content of roots was not significantly affected. In both data sets direction of responses was variable. A sensitivity analysis of carbon budgets under elevated CO<sub>2</sub> identified changes in respiration rate, and to a lesser extent carbon content, as important factors affecting the growth response to elevated CO<sub>2</sub> in quite a number of cases. Any comprehensive analysis of growth responses to increased CO<sub>2</sub> should therefore include measurements of these two variables.
