Marine biologists have discovered a vibrant community of ecologically important microbes living at the bottom of the 7 mile (11 km) Mariana Trench — the deepest part of the Earth's surface.
Back in 2010, scientists sent an unmanned submersible to an area in the trench known as the Challenger Deep. It scooped up some muddy sediment and brought it back to the surface for further analysis. The biologists weren't sure about how much life they were going to find, thinking that the conditions were likely too severe. Water pressure at those depths are thousands of times greater than at sea level. But not only did they find life, they found plenty of it.
And in fact, the scientists found so much deep sea bacteria that they now suspect it plays a key role in the carbon cycle and the regulation of the planet's climate.
The Independent reports:
“These microbes may in fact be the ones that are the closest to the centre of the Earth, the deepest living organisms that we have seen. They are probably the deepest observed community of microbes below sea level,” said Professor Ronnie Glud of the University of Southern Denmark.
“We expected to see microbes there but we didn’t expect them to flourish and to be so efficient. What is really surprising is that we have seen bacteria that operate so efficiently at these depths,” Professor Glud said.
The microbes are feeding off the constant stream of organic matter that sinks to the seabed in the Pacific Ocean. In doing so, they play a crucial role in the global carbon cycle, which affects the amount of carbon dioxide circulating in the atmosphere, he said.
“We know very little about what is going on down there or what impact the deep-sea trenches have on the global carbon cycle as well as climate regulation,” he added
Read the entire study at Nature Geoscience.