“This provides us with new boundary conditions on the limits for life,” said Peter Doran, professor of earth and environmental sciences at the University of Illinois at Chicago(UIC). “The low temperature or high salinity on their own are limiting, but combined with an absence of solar energy or any new inputs from the atmosphere, they make this a very tough place to make a living.”
The research team collected samples of brine within the ice by drilling out cores.
They found that the brine:
- has no oxygen
- is slightly acidic
- contains high levels of organic carbon and molecular hydrogen
- contains both reduced and oxidized compounds
Their findings were surprising, as the conditions beneath the ice are dark, cold, extremely salty, and completely isolated.
“Geochemical analyses suggest that chemical reactions between the brine and the underlying sediment generate nitrous oxide and molecular hydrogen,” said Fabien Kenig, also a professor at UIC. “The hydrogen may provide some of the energy needed to support microbes.”
“We’d like to go back and find if there is a proper body of brine without ice down there,” said Doran. “We’d also like to get some sediment cores from below that to better establish the history of the lake. In the meantime, we are using radar and other geophysical techniques to probe what lies beneath.”
To learn more:
- Read the full news release: UIC Scientists Find Ancient Microbes in Salty, Ice-Sealed Antarctic Lake
- Find the full study, published in the journal PNAS, here: Microbial life at −13 °C in the brine of an ice-sealed Antarctic lake
Copyright © 2012 by Marine Science Today, a publication of Marine Science Today LLC.