Response of antarctic marine diatoms to environment modification

Environmental manipulation and competition experiments on cultured and natural diatoms will identify the response of key taxa to environment modification. Understanding the environmental factors governing diatom distribution and natural variability will provide a basis to interpret palaeo-environment records, and allow predictions how this temperature-sensitive ecosystem will respond to future change.Environmental manipulation and competition experiments using diatoms will identify the response of key taxa to environment modification. Understanding the environmental factors governing their distribution and natural variability will provide a basis to interpret palaeo-environment records, and allow predictions how this temperature-sensitive ecosystem will respond to future change.Diatoms for the experiments were collected in 2002 (Aurora Australia, Voyage 1) and 2003 (Aurora Australis, Voyage 1). On each occasion water from the ship's online seawater tap was filtered through a 20 micrometre plankton net for up to one hour into a sample jar. A portion of the sample was preserved in lugol's iodine for later phytoplankton analysis, and the rest of the sample maintained alive in the dark in seawater at a constant low temperature. The live sample is maintained at the AAD for culturing and environment manipulation and competition experiments.Project 2364Twelve water samples were collected from 23/10/03 to 27/10/03, in open seawater between 60 degrees 45' S and 50 degrees 02' S. At each site, the following data were recorded from the ship's data logger: latitude, longitude, UTC time, local time, water depth, salinity, water temperature, fluorescence, UVB, and conductivity.