Heading south to Antarctica in search of sulphur
Four UTS scientists commence their journey to Antarctica this week working on a project supported by the Australian Antarctic Science Grant Program. The project is aimed at examining the role of sulphur compounds in Antarctic phytoplankton-bacteria relationships. Often referred to as the distinctive “smell of the sea” these compounds, such as DMSP (dimethylsulphoniopropionate), drive many marine food-web interactions and link ocean chemistry to global climate through the release of aerosols that influence cloud formation.
The team comprising Drs Katherina Petrou, Jean-Baptiste Raina, Daniel Nielsen and PhD student Eva Fernandez will explore how changes in environmental conditions, such as those expected from global warming, influence fundamental relationships responsible for ocean productivity.
“The Antarctic marine ecosystem is an important 'hot spot' of productivity, supporting global marine biodiversity through photosynthesis performed by phytoplankton. These microscopic marine plants support fisheries yields and help drive the cycling of chemicals that control our climate. Any shift in the way marine microbes interact will have a profound effect on the health of the planet,” says Chief Investigator, Dr Katherina Petrou, who leads the Marine Microphytology Lab in the UTS School of Life Sciences.
The researchers will conduct their research at Davis, the most southerly Australian Antarctic station, collecting offshore water samples for analyses in the on-site laboratory and deploying novel technology such as chemotaxis chambers designed by Dr Jean-Baptiste Raina from UTS Climate Change Cluster.
“We hope to measure how many different marine microbes are attracted to the specific sulphur compounds produced by algae and placed in the chambers. This will give us a real understanding of the importance of these compounds in the functioning of the marine food web,” Dr Raina says.
C3 PhD student Eva Fernandez will run a number of incubation experiments, including one that will investigate how increased ultraviolet light exposure affects phytoplankton production of DMSP and its subsequent fate. Scientists have hypothesized that ocean warming will cause ocean stratification, trapping algae in upper water layers where they will be exposed to more UV light than under current conditions.
Antarctic water samples will also make their way back to Australia for metagenomics analysis.
“This allows us to identify the microbial species present,” says Dr Daniel Nielsen.
The science just might be the easy part. The journey to and from Davis research station sounds straightforward on paper but is an intrepid adventure in itself. From Hobart the team fly to Casey research station, located just outside the Antarctic Circle, followed by a ride in a US Army Hercules to the plateau beyond Davis, where a helicopter will ferry them to the research facility that will be their home for the next four weeks. A two week stint on board the Aurora Australis will see them return to Hobart around mid-March.
Dr Petrou, a return visitor to the white continent, is gearing up for science communication via Twitter. While she may be excited to share images of the beautiful diatoms she sees down the microscope, those left turning green with envy at home are demanding penguin and seals feature every so often!
- Scientists hoping microbes key to fighting global warming (ABC TV, 2/3/17)
- Australian Antarctic Division
- Exposing a sulphur-mediated microbial liaison (Australian Antarctic Magazine 31: 10-11, 2016)
- Characterising the microbial interactions that drive organic sulphur cycling in Antarctic waters (Australian Antarctic Science project)