21 October 2009
Project Title: Tree Leaf - and Branch - Trait Coordination Along and Aridity Gradient
Supervisor: Derek Eamus
PhD conferred: 2009
I am a plant ecophysiologist working for the Terrestrial Ecohydrology Research Group (TERG) within C3. My research interests within plant science include the hydraulic function of leaf stomata (especially the mechanisms by which stomata respond to changes in humidity), hydraulic and chemical signalling (particularly in the response to variation in plant water availability), the links between leaf-level carbon assimilation and plant hydraulic architecture and the factors that influence stand water use.
I completed a Bachelor of Environmental Biology (Hons) at UTS in 2003 and have continued my research at UTS, attaining a PhD in Environmental Science in 2009. Prior to commencing a PhD, my research focused on the effect of variation in the leaf cuticular conductance, xylem sap abscisic acid concentration (a plant stress hormone) and xylem sap pH on the stomatal response to increasing atmospheric humidity. My doctoral work was concerned with how branch hydraulic architecture and ecosystem climate influence the relative use of water and nitrogen in leaves and the implications of this for CO2 assimilation rates.
This type of research is part of a bigger question about understanding the water balance of a site - so important in a country like Australia – because the more insight we have into what happens at the leaf and branch levelthe better we can predict what happens at a larger scale, for example a forest, and then we have better inputs for water balance models used by environmental managers and policy makers.
Post doctoral work at UTS:
I am currently employed as a Post Doctoral Research Fellow where the focus of my work is on measuring the water use of several woodland ecosystems located in NSW, WA and the NT. The team is using several methods for estimating water use, including Bowen ratio, eddy covariance and surface layer scintillometry. The Scintillometer project is especially interesting because this is a relatively new technology and it’s the first time a scintillometer has been used in Australia for this purpose.
The focus of this research is on comparing the estimated energy balances of each of these techniques, establishing the relative importance of environmental variables in terms of their effect on stand water-use, and developing and testing the generality of predictive models of tree- species- and stand transpiration. As part of this project, we are also examining the effectiveness of several revegetation strategies in restoring the hydrological function of waste disposal and mine sites. Ultimately the aim is for environmental managers to get data on evapotranspiration more quickly and cheaply by using more straightforward methods that don’t require difficult to measure variables.
It was a relief to be awarded my PhD after four years of intense work. I really enjoyed the problem solving aspect of my research and the way science helps you to think critically. I had to overcome a number of problems relating to developing self sustaining systems for the equipment in the field and it’s satisfying to get a good outcome.
I’ve done some undergraduate teaching and demonstrating and enjoyed that so it’s possible I’ll do more of this in the future. At the moment I’m enjoying being part of such a multi-skilled team and one that aims to make a difference to water management in Australia.