Dr Tarryn Turnbull

Summary

My research focuses on the eco-physiology of Australian native plants, specifically, how leaf structure and biochemistry underpins whole-plant carbon gain and water use.

Research interests

I am primarily a field-based plant physiologist, studying plants that comprise native Australian landscapes. My recent work is concentrated in sub-alpine ecosystems of ACT, NSW and VIC, however I routinely support other members of our lab group’s work in riparian regions of WA’s arid rangelands.

My research involves investigating how leaf physiological processes (e.g. photosynthesis and respiration) are coupled with plant, and ecosystem ecology. Broadly speaking this includes:

• ultra-structural analysis of photosynthetic and respiratory organelles;
• quantification of substances involved in photosynthesis;
• determination of limitations to photosynthesis (biochemical, substrate, temperature, nutrients and light quality);
• relationships between photosynthesis and within-plant allocation of biomass; and
• relating ecosystem-level water use to patterns of carbon assimilation.

The instrument which I rely most on is an infra-red gas analyzer, which I use to measure rates of photosynthesis and respiration. This is coupled to other field-based measurements including automated weather station records, whole-tree measures of sap-flow (heat ratio method sensors), stomatal conductance (porometers) and measures of leaf water status (pressure vessels). My field-work is complemented by a range of lab-based techniques including analysis of structural and ultra-structural attributes of leaf cells and tissues via light microscopy and transmission electron microscopy and analysis of leaf chemistry (primarily nitrogen and phosphorus fractions). These measures are then integrated into models to predict ecosystem-level dynamics of water and carbon fluxes.

Background

I completed a double Bachelor's degree in Forest Science (Hons) and Science at the University of Melbourne in 1999. Following a couple of years of employment in the private sector as a Forest Ecologist, I returned to university to complete a PhD titled “Photosynthetic responses to light, nitrogen, phosphorus and pruning of Eucalyptus in south-eastern Australia”, again at the University of Melbourne. This degree was granted in 2006.

My post-doctoral appointment was at the University of New South Wales (UNSW), where I was employed as a Tree Physiologist.

Currently I am a Research Fellow in Ecophysiology at the University of Sydney, and laboratory manager for the Adam’s lab group.

I have previously co-supervised an honours student at UNSW, and am also currently co-supervising another.

Recent publications

• Turnbull TL, Warren CR and Adams MA (2007) Novel mannose-sequestration technique reveals variation in sub-cellular orthophosphate pools do not explain effects of P nutrition on photosynthesis in Eucalyptus globulus seedlings. New Phytologist 176, 849 - 861.
• Turnbull TL, Kelly N, Adams MA and Warren CR (2007). Within-canopy nitrogen and photosynthetic gradients are unaffected by added fertiliser in field-grown Eucalyptus globulus. Tree Physiology 27, 1607 – 1617.
• Turnbull TL, Adams MA and Warren CR (2007) Increased photosynthesis and metabolism after partially defoliating Eucalyptus globulus is not attributed to increased allocation of leaf nitrogen to photosynthetic enzymes or pigments. Tree Physiology 27, 1481 – 1492.

Contact

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