University of Virginia
Department of Biology
Enrollment Year: 2006
Email Address: poikawa at yahoo.com
Atmospheric Mentor: John Mak, SUNY Stony Brook University
Biospheric Mentor: Manuel Lerdau, SUNY Stony Brook University
I am interested in plant physiological ecology and biosphere-atmosphere interactions. Specifically, I study the physiological and ecological mechanisms regulating biogenic volatile organic compound flux to the atmosphere. My current project focuses on the long-term volatile emission responses of trees to herbivory in temperate deciduous forests. I hope to elucidate the implications of plant physiological ecology for ecosystem level processes.
An investigation on mechanisms regulating biogenic methanol emissions
Methanol, the second most abundant organic gas in the atmosphere, has significant impacts on atmospheric chemistry. Biogenic methanol is the single largest source of methanol to the atmosphere (Jacob et al., 2004). Fundamental biological plant processes regulating methanol emissions are not clearly understood. Current literature indicates a positive correlation between methanol emissions and stomatal conductance, yet studies confirming the correlation do not explain how emissions are regulated (Fall 2003, Niinemets and Reichstein 2003). Studies investigating the effect of herbivory on methanol emissions are limited to a minority of plant species over short time scales (Fall et al. 1999, Warneke et al. 2002, Penuelas et al. 2005). I proposed to investigate both physiological relationships between stomatal conductance and methanol emission and between herbivory and methanol emission with the intention of improving biogenic methanol emission models.
I will elucidate physiological mechanisms responsible for the regulation of methanol flux by conducting direct measurements on methanol emissions, intercellular concentrations of methanol and methanol metabolism in a variety of species. Comprehensive study of herbivore effects on methanol emissions will also be conducted on a variety of volatile-emitting plant species and insect species.
Due to the fact that research on mechanisms regulating methanol flux is lacking, there are great uncertainties in atmospheric methanol budgets. The main objective of the study is to alleviate these discrepancies by providing a clear mechanistic understanding of methanol emission. The results of the experiment will allow a more accurate incorporation of biogenic methanol flux into climatic models and global carbon budgets.