Marine Biodiversity and Ecosystems

What we do: We aim to provide ground truth data of total primary productivity and biodiversity in Antarctic sea ice, and study the relationship between the extent of ice cover and total primary production along an extensive north-south transect of the western coast of the Ross Sea.

Why we do it: This study will be the first to assess the effect of global climate change on primary productivity in ice covered coastal ecosystems in the Ross Sea and will be used to predict future scenarios of reduced ice at southerly sites.

Some things we've found out so far: Several experiments on live algae and bacteria were carried out to determine their responses to the changes in salinity, temperature and light that they will encounter during the processes of ice formation at the start of winter and ice melting in summer.  Comparisons between bottom ice algae and those growing in brine within 30cm of the surface, showed distinctly different patterns of response to these treatments. Together, this information will enable us to describe the distribution and biodiversity of these organisms and to predict of the effect of future global warming on southern ocean ecosystems.

This research contributes to the Latitudinal Gradient Project (LGP).

Recent publications:
Ryan, K.G. et al. Comparison of the microalgal community within fast ice at two sites along the Ross Sea coast, Antarctica. Antarctic Science 18 (4): 583-594. 2006.

McMinn, A et. al. Spring sea ice photosynthesis, primary productivity and biomass distribution in eastern Antarctica, 2002–2004. Marine Biology doi: 10.1007/s00227-006-0533-8. 2006.

Ralph, P., McMinn, A, and Ryan, K.G. Short-term effect of temperature on the photokinetics of microalgae from the surface layers of Antarctic pack ice.  Journal of  Phycology 41: 763 – 769. 2005.

Martin, A. Antarctic bacteria, sea ice ecosystem dynamics, and global climate change. MSc. Victoria University of Wellington. 2005. View Abstract.