Dr Malcolm Possell

Summary

Knowing how the biosphere affects the atmosphere and how the atmosphere affects the biosphere is one crucial component in understanding how the Earth works as a system and supports the life dependent upon it.

Research interests

My current research interests are on the flux of trace gases, such as CO₂, CO and volatile organic compounds, and particles between the biosphere and atmosphere and the mechanisms controlling these fluxes. Trace gases and particles have significant impacts on air quality and climate and subsequently on plant, animal and human wellbeing. My research in this area involves making laboratory and field studies of emissions directly from vegetation and determining how and why different biotic and abiotic stresses affect the biosynthesis and emission of these compounds. These stresses include herbivory, transient high temperatures, reduced and elevated CO₂, and elevated ozone. More recently, my work focuses on trace gas emissions as a consequence of wildfires and understanding the factors controlling the composition of smoke. Results from these studies allow us to better parameterise the observed responses and improve trace gas emission models. As trace gas emission models are used within Earth System science models we can then attempt to assess how changes in fluxes impact all the interconnected components of the Earth system now and in the future.

Background

Malcolm Possell graduated from the University of East Anglia (UK) with a B.Sc. (Hons) in Environmental Science and a Ph.D. in Environmental Science from Lancaster University (UK). Prior to working for the University of Sydney, he worked as a research associate at the University of Sheffield (UK) (2003-2004) and Lancaster University (2004-2010) on projects aimed at understanding the biosynthesis and emission of the volatile organic compound isoprene under different abiotic and biotic conditions.

Recent publications

• Possell M., Ryan A., Vickers C.E., Mullineaux P.M. & Hewitt C.N. (2010) Effects of fosmidomycin on plant photosynthesis as measured by gas exchange and chlorophyll fluorescence. Photosynthesis Research, 104, 49-59.
• Vickers C.E., Possell M., Hewitt C.N. & Mullineaux P.M. (2010) Genetic structure and regulation of isoprene synthase in Poplar (Populus spp.). Plant Molecular Biology, 73, 547-558.
• Possell M. & Hewitt C.N. (2009) Gas exchange and photosynthetic performance of the tropical tree Acacia nigrescens when grown in different CO₂ concentrations. Planta, 229, 837-846.
• Ryan A., Cojocariu C., Possell M., Davies W.J. & Hewitt C.N. (2009) Defining hybrid poplar (Populus deltoides x Populus trichocarpa) tolerance to ozone: identifying key parameters. Plant Cell and Environment, 32, 31-45.
• Vickers C.E., Possell M., Cojocariu C.I., Velikova V.B., Laothawornkitkul J., Ryan A., Mullineaux P.M. & Hewitt C.N. (2009) Isoprene synthesis protects transgenic tobacco plants from oxidative stress. Plant Cell and Environment, 32, 520-531.
• Laothawornkitkul J., Moore J.P., Taylor J.E., Possell M., Gibson T.D., Hewitt C.N. & Paul N.D. (2008) Discrimination of Plant Volatile Signatures by an Electronic Nose: A Potential Technology for Plant Pest and Disease Monitoring. Environmental Science & Technology, 42, 8433-8439.
• Laothawornkitkul J., Paul N.D., Vickers C.E., Possell M., Taylor J.E., Mullineaux P.M. & Hewitt C.N. (2008) Isoprene emissions influence herbivore feeding decisions. Plant Cell and Environment, 31, 1410-1415.
• Wilkinson M.J., Owen S.M., Possell M., Hartwell J., Gould P., Hall A., Vickers C. & Hewitt C.N. (2006) Circadian control of isoprene emissions from oil palm (Elaeis guineensis). Plant Journal, 47, 960-968.
• Heath J., Ayres E., Possell M., Bardgett R.D., Black H.I.J., Grant H., Ineson P. & Kerstiens G. (2005) Rising atmospheric CO₂ reduces sequestration of root-derived soil carbon. Science, 309, 1711-1713.
• Possell M., Hewitt C.N. & Beerling D.J. (2005) The effects of glacial atmospheric CO₂ concentrations and climate on isoprene emissions by vascular plants. Global Change Biology, 11, 60-69.

Contact

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