After more than 150 million years of isolation the podocarps that dominate the forests of the west coast of the south island of New Zealand have remarkably slow growth rates by comparison to most other forest tree species. The question is, why? In New York, the aging eastern deciduous forests continue to rapidly accumulate carbon. Could this be the result of the high levels of atmospheric N deposition this area receives? When plants are grown in elevated CO2 photosynthesis is stimulated initially but often this enhancement does not last and given time, a strong acclimation to the new growth environment can occur. Is there a reason why some plants acclimate to CO2 and others do not? Plant respiration is often thought of as the processes by which plants loose carbon during the night. How then can we estimate the contribution of respiration to the carbon balance of arctic plants which never experience night during the growing season? Plant cells from leaves of plants grown in elevated CO2 tend to have twice the number of mitochondria and chloroplast as cells from plants grown in ambient CO2. Is there a link between this structural observation and physiological function?
These are a few examples of the type of research questions my lab is currently working on. The objective of this research is to explain processes in plant and ecosystem ecology in terms of the physiological, biochemical and biophysical processes involved. Ultimately we hope to increase our understanding of both the role of the Earth's vegetation in the global carbon cycle and the interactions between the carbon cycle and the Earth's climate system.