Nikolaus Csaszar

Estimating Potential for Adaption of Corals to Climate Change


Nikolaus B. M. Császár Current Appointment: PhD Candidate Contact: Aquatic Photosynthesis Group Department of Environmental Sciences University of Technology, Sydney PO Box 123 Broadway NSW 2000 Australia Office: Building 4, Level 5, Room 66 (City Campus) Phone: 9514 8345 Fax: 9514 4079 Email: Nikolaus.Csaszar@student.uts.edu.au Reef building corals are known to harbour single-celled microalgae (also called “zooxanthellae”), which supply the coral host with organic products of photosynthesis in a unique and mutual symbiosis. The widely known phenomenon of coral bleaching is described as the expulsion of photosynthetically damaged zooxanthellae (Symbiodinium spp.) from coral host tissue or degradation of algal pigment within the host due to abiotic factors such as elevated seawater temperature and/or increased irradiance, thereby leading to the disruption of the obligate symbiosis between the animal and the algae. Coral bleaching events have increased worldwide in frequency and severity during the last two decades and simulation models using current data on bleaching incidence as well as scenarios under projected climate change; predict the ecological collapse of the world’s coral reefs within the 21^st century. The main focus of this PhD project is to find out whether the coral/algal symbiosis is able to adapt fast enough to global climate change. A major emphasise will be given on the photo-physiological characteristics of the single-celled symbiotic microalgae living within the corals. There is already evidence that the heat susceptibility of the zooxanthellae is characterized by the different ratios of direct damage to their photosynthetic apparatus versus the rates of its repair. Principal Supervisor Associate Professor PETER RALPH, University of Technology, Sydney, Australia Co-Supervisor Doctor MADELEINE VAN OPPEN, Australian Institute of Marine Science, Australia Alternate Supervisor Professor GREG SKILBECK, University of Technology, Sydney, Australia