Studying the Impact of Elevated CO2
on a Florida Scrub-oak Ecosystem

Plant Phyisologist Bert Drake and his colleagues at SERC's CO2 lab along with Dr. Peter Stiling of the University of Western Florida have have been conducting experiments on the effects of atmospheric CO2 concentration on this scrub oak ecosystem since 1996.

Responses of the mechanisms of carbon cycling in Florida Scrub Oak to elevated CO2 have been observed at virtually all levels of the ecosystem. Our main findings are that the ecosystem accumulates a lot of additional carbon in the high CO2 environment and, at the same time, uses less water to accomplish this. We also find that this additional carbon accumulates mainly in the roots. There are also effects on insects which consume more leaves in the elevated CO2 condition, but are more intensely attacked by their predators.

Our continuing research on effects of elevated CO2 in this Florida scrubland is organized around five questions that encompass the primary responses to rising atmospheric CO2 and climate change.

1. How important is acclimation of photosynthesis to CO2 fertilization of ecosystem carbon assimilation?

2. What are the mechanisms by which nutrient limitations mitigate growth response to elevated atmospheric CO2?

3. What are the mechanisms for improved water balance of plants to increase ecosystem CO2 fertilization? Does stimulation of growth by elevated CO2 deplete soil water?

4. Will elevated CO2alter partitioning of carbon between foliage, wood and roots?

5. Will elevated CO2 increase ecosystem carbon?

Research Questions