Elevated CO2Does it Really Matter for Plants That Are Already Experiencing Higher than Ambient Levels?
Abstract:
Atmospheric concentration of CO2 has increased significantly over the past few decades and so have
the concerns about the greenhouse effect and global warming. One of the extensively explored aspects is the
response of ecosystem components in terms of performance and productivity. A host of information thus
generated suggests a positive effect of elevated CO2 on functioning of plants from seed germination through
maturation vis-a-vis rhizospheric microbial functions. Amazingly, most (if not all) of the researches deal with
plant responses to CO2 at levels twice that of ambient with a view that fossil fuel burning and increased
agricultural activity are adding substantially to the atmospheric CO2 . As such, hardly any attention has been
paid to the contribution of soil respiration (includes that of microbes and plant roots) to CO2 concentration
within the soil matrix as well as above the soil surface. This study presents an analysis of the available literature
to demonstrate that by default the plant communities are already functioning at elevated levels of CO2 . Any
further increase due to human intervention (especially fossil fuel burning) may not have a significant effect on
plant functions and productivity. Hence the potential dangers of elevated CO2 resulting from fossil fuel burning
should not be considered as alleviated through increased plant productivity.
How to cite this article
F. Azam and S. Farooq, 2005. Elevated CO2Does it Really Matter for Plants That Are Already Experiencing Higher than Ambient Levels?. Pakistan Journal of Biological Sciences, 8: 175-180.
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