Sharon Robinson Research Area
Antarctic plants and global change
Plants in Antarctica are already growing at the extremes of their physiological limits and have low genetic diversity compared to populations from temperate and sub-Antarctic sites reducing their capacity for adaptive change in the face of predicted regional climate change. My group is using a range of molecular and physiological techniques to predict how terrestrial biodiversity in Antarctica will change as a result of climate change.
Our work is providing important insights into the biology of these plants that survive and grow in conditions equivalent to a freezer. Plant growth in Antarctica is very slow, modern radiocarbon techniques to show that East Antarctic mosses have average growth rates between 0.6 and 1.3 mm yr -1 . Warming and increased precipitation predicted for the Antarctic over the 21 st century are likely to increase moss growth rates, whereas the already observed increase in wind speeds may reduce water availability and negatively impact the growth of mosses. The timing and balance between the positive influence of warming and the negative influence of high wind speeds are likely to determine the fate of East Antarctic moss communities.
Our research provides evidence that the Antarctic endemic moss Schistidium antarctici is likely to be more susceptible to climate change than two co-occurring cosmopolitan species Ceratodon purpureus and Bryum pseudotriquetrum (Robinson et al 2005 PDF 681k, Wasley et al 2006a, b). The cosmopolitan species have high levels of protection from UV-B radiation compared to the endemic and show less evidence of UV-induced DNA damage, indicating the endemic species may be disadvantaged under continuing springtime ozone depletion. Our results also suggest that cell wall compounds may be an important component of the UV defences of lower plants.
My group is investigating:
How Climate Change is altering plant communities in Antarctica. This work is focused on the impact of changes in water and nutrient availability on plant growth in Antarctica (see Robinson et al 2000, 178k PDF, Robinson et al. 2005 681k PDF, Wasley et al (2006a & b). These results feed into the only State of the Environment Indicator for Antarctic plants for which I am the custodian.
The impact of the ozone hole and the resultant increase in UV-B radiation on these communities (sunscreen pigments, DNA damage and persistence of genetic mutation in Antarctic plants). (see Lovelock, C.E. and Robinson, S.A. (2002) ; Robinson et al. 2005 )
Bioactive compounds that are responsible for the extreme desiccation and cold tolerance of Antarctic plants.
Using remote sensing to map Antarctic flora
Our research in Antarctica also involves a collaboration with colleagues at CSIRO Land and Water and at the University of Tasmania to assess the practicality of using remote sensing to map and monitor vegetation change in these sensitive communities. This work is focussed on the subantarctic Islands (Macquarie and Heard) (Lovelock, C.E. and Robinson, S.A. (2002)
Current students
Laurence Clarke - PhD
Mary Rosengren - DCA
Johanna Turnbull - MRes
Melinda Waterman - BBiotech Hons
Future opportunities for research
- How are climate change and humans influencing terrestrial vegetation dynamics in Antarctica ?
- How does UV-B effect Antarctic mosses?
- What UV screening compounds do they produce?
- How do Antarctic plants survive desiccation? What compounds are involved?
- Using remote sensing to map and monitor vegetation change on subAntarctic Islands (with University of Tasmania)
Related publications
Clarke, L.J., Robinson, S.A. (2008) Cell wall-bound UV-screening pigments explain the high ultraviolet tolerance of the Antarctic moss, Ceratodon purpureus. New Phytologist 179 776-783.
Clarke, L.J., Robinson, S.A., Ayre, D.J. (2008) Genetic structure of Antarctic populations of the moss Ceratodon purpureus . Antarctic Science ( online doi:10.1017/S0954102008001466).
Clarke, L.J., Robinson, S.A., Ayre, D.J. (2008) Somatic mutation and the Antarctic ozone hole Journal of Ecology 96 378-385. Editor's choice article for March 2008.
Dunn, J.L. Robinson, S.A. (2006) UV-B screening potential is higher in two cosmopolitan moss species than in a co-occurring Antarctic endemic moss - implications of continuing ozone depletion. Global Change Biology 12 2282-2296.
Hennion, F., Huiskes, A, Robinson, S., Convey, P. (2006) Physiological traits of organisms in a changing environment. In: Trends in Antarctic Terrestrial and Limnetic Ecosystems: Antarctica as a Global Indicator. ( Bergstrom, D.M., Convey, P. and Huiskes, A.H.L. (eds) Springer, Dordrecht , The Netherlands. 1-4020-5276-6 p129-155
Wasley, J., Robinson, S.A., Popp, M., Lovelock, C.E. (2006a) Climate change manipulations show Antarctic flora is more strongly affected by elevated nutrients than water. Global Change Biology 12 1800-1812.
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