I am a marine biologist who works in the Future Reefs Reseach Group as part of the C3 Climate Change Cluster. My current research focus is to understand how decreased oxygen availability (hypoxia) due to climate change and increasing human pressure on coastal systems, will affect tropical coral reefs into the future.
I also oversee the running of our state-of-the-art aquarium facility, where we grow and propagate a wide range of corals from the Great Barrier Reef (GBR) for use in cutting-edge research that allows us to make better predictions of how coral reefs may respond to climate change.
- Coral ecophysiology
- Aquaculture and captive proprogation of corals
- Photobiology of corals and algae
- Using bio-optics (e.g. Fast Repetition Rate fluorometry [FRRf]) to measure aquatic primary production
Hughes, D.J., Varkey, D., Doblin, M.A., Ingleton, T., Mcinnes, A., Ralph, P.J., van Dongen-Vogels, V. & Suggett, D.J. 2018, 'Impact of nitrogen availability upon the electron requirement for carbon fixation in Australian coastal phytoplankton communities', Limnology and Oceanography.View/Download from: Publisher's site
© 2018 Association for the Sciences of Limnology and Oceanography. Nitrogen (N) availability affects phytoplankton photosynthetic performance and regulates marine primary production (MPP) across the global coast and oceans. Bio-optical tools including Fast Repetition Rate fluorometry (FRRf) are particularly well suited to examine MPP variability in coastal regions subjected to dynamic spatio-temporal fluctuations in nutrient availability. FRRf determines photosynthesis as an electron transport rate through Photosystem II (ETR PSII ), requiring knowledge of an additional parameter, the electron requirement for carbon fixation (K C ), to retrieve rates of CO 2 -fixation. K C strongly depends upon environmental conditions regulating photosynthesis, yet the importance of N-availability to this parameter has not been examined. Here, we use nutrient bioassays to isolate how N (relative to other macronutrients P, Si) regulates K C of phytoplankton communities from the Australian coast during summer, when N-availability is often highly variable. K C consistently responded to N-amendment, exhibiting up to a threefold reduction and hence an apparent increase in the efficiency with which electrons were used to drive C-fixation. However, the process driving this consistent reduction was dependent upon initial conditions. When diatoms dominated assemblages and N was undetectable (e.g., post bloom), K C decreased predominantly via a physiological adjustment of the existing community to N-amendment. Conversely, for mixed assemblages, N-addition achieved a similar reduction in K C through a change in community structure toward diatom domination. We generate new understanding and parameterization of K C that is particularly critical to advance how FRRf can be applied to examine C-uptake throughout the global ocean where nitrogen availability is highly variable and thus frequently limits primary productivity.