Kirsty Milner

Supervisor/s: Dr Andy Leigh (primary), Associate Professor Stella Valenzuela (co-supervisor), Professor Kris French (co-supervisor, UoW)

Project title: The price of heat stress: functional and resource constraints of thermal tolerance in arid zone plants

Please describe your research project
Extreme climate events (like heat waves) are expected to become more frequent and intense under climate change. Extreme events are more likely to cause stress damage to living organisms than an increase in average annual temperatures. Nowhere will this be more apparent than in deserts where organisms are already living at the edge of what is biologically possible. In Australian deserts extreme events are coupled with nutrient-poor soil and highly unpredictable rainfall.

Terrestrial plants are unable to move from adverse conditions and Australian arid zone plants are mostly evergreen, meaning their leaves must endure extreme conditions year round. Plants have developed a suite of mechanisms in order to tolerate harsh environments but these may come at the cost of resource re-allocation. For Australian desert plants the challenge comes from assigning scarce resources to thermal tolerance versus other cellular processes, such as growth and reproduction. My project will consider the trade-offs that come with thermal tolerance.

What is the aim of your project?
My research aims to test how plants in nutrient-poor environments prioritise resource allocation during heat stress events. I will compare plants, from wetter versus drier microhabitats, nitrogen fixers versus non-nitrogen fixers, grown in common gardens under different experimental conditions (high versus low nutrients, high versus low water). I will use molecular techniques to answer ecological questions. I am interested in changes in plant species’ thermal damage threshold, production and regulation of heat shock proteins and other physiological stress responses. To quantify the cost of heat stress and drought I will measure effects on growth rates and reproduction.

Photo courtesy Carl Davies and CSIRO.

Why did you choose to pursue a research degree as opposed to going into the work force? Why this area of research?
I enjoyed my undergraduate study so much I did an honours year and enjoyed research so much I decided to continue with a PhD. Also, jobs in environmental science are competitive and a research degree is a way to get ahead. This degree gives me more than just disciplinary knowledge; I get the chance to learn skills that are applicable to many work place activities. 

The other reason to continue with a research degree is to learn more about my area of research—plants and plant ecology. Who wouldn’t want to get to know plants better? They are the base of the food chain, produce oxygen and capture carbon, provide habitat and are aesthetically pleasing. They don’t bite or move which makes them good to work with.

What is your daily activity?
At the moment I’m in the early stages of my PhD. This means I have many forms to fill in. I’m reading and reading a lot of background information. Trying to find where my research will fill a knowledge gap on how desert plants cope with heat stress. I’m getting down to specifics, with the kinds of questions I will ask and designing the experiments that will help me answer them.

Eventually I will get out into the field. It’s what I enjoy most. I’ll be working at the Australian Arid Lands Botanic Gardens in SA. I will collect leaf material to bring to UTS to analyse in the laboratory.

What attracted you to research at UTS Science?
I came to UTS as an undergraduate after attending the Open Day and meeting some lecturers who showed such enthusiasm for the course. That enthusiasm continued through my undergrad degree. I found the practical side of the undergrad hugely important, it helped prepare me for research. I have a good support network at UTS, I know this will be important when the research and PhD start to get tricky.

My future
I’m not entirely sure on my career direction, though conservation will have to be a big part of it. I would like to think my research will be used to better predict the impact of climate change on arid plant species. That my research may help direct conservation towards protecting species or areas that are most at risk in a changing environment.