The researchers analyzed soil samples from the extremely dry Atacama desert.
Based on a new study, they found a rich biosphere under the Atacama Desert in Chile, reports Live Science. The living world consisting of bacteria can be found 2-4 meters below the surface, the discovery can also help in the research of Martian life.
Experts have previously recorded microbial life 80 centimeters deep in the desert soil, Lucas Horstmanna colleague of the GFZ German Institute of Earth Sciences and his colleagues, the new biosphere found in the bone-dry Yungay valley is at the same time completely isolated from the surface.
In communities it is Actinobacteria dominates, this group is very diverse, its members are also present in other extreme environments, such as the Arctic, hot springs and extremely salty seas.
As the researchers pointed out: very little is known about the microbial life found in deeper sediment layers. The communities just presented probably represent the upper limit of the deep biosphere beneath the hyperarid desert soil.
The team also found actinobacteria at a depth of 2-5 centimeters, and even lower a Firmicutes organisms belonging to the tribe. They can withstand high salt concentrations and do not require oxygen to survive.
The Atacama is the world’s driest hot desert, only a few animals can survive the harsh conditions, but resistant bacteria thrive in the salty, mineral-rich soil. To get to know these microorganisms better, the experts took soil samples from the Yungay Valley and then carried out genetic tests.
By looking for intracellular DNA, the team was able to detect traces of still-living microbes. The data revealed that microbes are present in large numbers up to 80 centimeters, but between 80 and 200 centimeters the salt concentration is too high even for them. A stable transition zone followed.
According to researchers, it is Actinobacteria its members may have settled in the river sediments about 19,000 years ago, which were then buried. The bacteria may survive by extracting water from the local plaster.
Due to its extreme environment, the Atacama Desert is often used as a terrestrial analogy for Mars. The new investigation may also contribute to the search for potential life on the red planet, as there are also gypsum deposits on the celestial body.
