Bacteria Thriving at World's Deepest Oceanic Trench

Researchers have found microbes in the deepest oceanic trench on Earth - the Mariana Trench, which is located at nearly 7 miles or 11 kilometers below sea level in the western Pacific.

The study of life in this inaccessible site revealed a community of bacteria that live in extreme pressures, which is 1,000 times higher than the pressure at the sea surface.

The expedition to Mariana Trench took place in the year 2010. Researchers have also sent a robot to bring data from the Japan Trench and the Kermadec-Tonga Trench near Fiji in the Pacific.

The microbes have to be evaluated at the site so that the researchers have accurate data about the conditions present in these trenches.

"If we retrieve samples from the seabed to investigate them in the laboratory, many of the microorganisms that have adapted to life at these extreme conditions will die, due to the changes in temperature and pressure. Therefore, we have developed instruments that can autonomously perform preprogrammed measuring routines directly on the seabed at the extreme pressure of the Marianas Trench," Ronnie Glud from Nordic Center for Earth Evolution at the University of Southern Denmark said in a news release.

Interestingly, the trenches had some 10 times more bacteria than the relatively shallow waters around them. Researchers say that the trenches are the "hot spots" for microbial life because these places have high amounts of dead and decaying matter.

"We have also made videos from the bottom of the Mariana Trench, and they confirm that there are very few large animals at these depths. Rather, we find a world dominated by microbes that are adapted to function effectively at conditions highly inhospitable to most higher organisms," said Glud.

The study is published in the journal Nature Geosciences.

Recently, a related study had found microbes living deep inside the Oceanic Crust.