Two Rhodes University microbiologists will join a team of 50 researchers from 30 countries to participate in the first circumnavigation of Antarctica. The purpose of this project is to lay the groundwork for understanding how marine ecosystems in the ‘Southern Ocean, which surrounds Antarctica, function on a large scale. The Southern Ocean and Antarctica are part of the polar regions which are critically affected by climate change.
“This is a once in a lifetime research cruise, the first time it is ever being done. We want to use this opportunity to shine a light on the hidden life in the marine systems, and also increase awareness of the global importance of the Southern Ocean,” shared Professor Rosemary Dorrington, DST/NRF SARChI Professor in Marine Natural Products Research.
The Southern Ocean refers to the region where Atlantic, Indian and Pacific Ocean waters come together to encircle Antarctica. The importance of the Southern Ocean is that it absorbs heat and is a major sink for carbon dioxide, CO², playing a critical role in mitigating the effects of global warming. Microscopic organisms including algae and bacteria remove this CO²from the water and convert it to biomass that sinks to the bottom, allowing the ocean to absorb more greenhouse gasses from the atmosphere. This process is known as carbon sequestration. However, as the water warms, the ability to absorb and sequester CO² decreases, accelerating the rate of global warming.
These microorganisms that are doing all this work in the Southern Ocean, drive CO² capture and cycling of nutrients are the bedrock of marine ecosystems, are invisible to the naked eye. “And we know almost nothing about who they are, what they do, how they will respond to climate change and what the consequences will be for the food chain that supports the visible marine world that we rely on for food,” said Dorrington.
PhD candidate Samantha Waterworth and Prof Rosemary Dorrington, of the Biochemistry and Microbiology Department, will participate in Leg 1 and Leg 3 of the cruise, respectively. The Russian Polar Research Vessel, R/N Akademik Treshnikov,will set sail from Cape Town Harbour on 20 December. The expedition consists of three legs: the first leg is from Cape Town, South Africa to Hobart, Australia, the second leg continues to Punta Arenas, South America and the third leg returns to South Africa on 18 March 2017.
“We will be collecting more than 800 samples. We will use molecular tools to study the microbial communities to see who is there, what are they doing and try to figure out why?” explained Prof Dorrington. “We are also interested in the potential for these microbes to produce novel chemicals (marine natural products) that can have pharmaceutical potential.”
“While the terrestrial systems are relatively well characterised, we know almost nothing about microbial dynamics in the Southern Ocean, despite the biological importance of the microbial food webs. This expedition will lay the foundation for understanding the open ocean ecosystem and we really need to understand how it works if we want to be able to mitigate the effects of climate change in the region and in Southern Africa,” stated Prof Dorrington.
South African researchers have been working on the Subantarctic Prince Edward Islands, which are critically important as breeding grounds for marine top predators (seals, penguins, albatross) for more than 50 years. These islands, are regarded as “Sentinels for climate change” because their environment is changing rapidly. Average sea water temperatures have risen by approximately 1.5oC and further warming will have catastrophic effect on the ability of the islands to support their unique marine wild-life. And the marine microbial communities are the first to respond to these changes.
“South African researchers are already active in the Southern Indian Ocean but through the ACE project, we are looking forward to develop South-South partnerships with South American countries like Brazil, Chile and Argentina, to look at the physical and biological dynamics of the South Atlantic. So the next step will be to develop the linkages with our South American partners,” added Prof Dorrington.
The third leg will coincide with Scifest Africa, which begins on 8 March 2017 to 14 March 2017. The researchers hope to be able to interact by Skype and Satellite phone every day so that learners can interact with them about the cruise, life on the Treshnikov and the work that they are doing.
The ship docks in Cape Town on 16 December and the Swiss Embassy is hosting an exhibition at the V&A Waterfront with displays and talks about the expedition. The Treshnikov will be visible at its mooring on East Pier. The researchers will be posting videos and photographs and sharing these on Instagram and an ACE Project Blog. Follow them on Instagram at “sa_ace_project”