The deepest natural trench in the ocean is the Mariana Trench located in the Western Pacific Ocean. Some parts go down 10,994 meters (36,070 feet) deep! To put it into perspective, that’s over 2,000 meters more than the height of Mount Everest. As you can imagine, it’s a completely different world down there. Most of it is still undiscovered. There is so much of the undersea world that scientists have yet to explore.
Little by little they find new things, unlike anything they’ve ever seen before. The latest of these fantastic finds from this subaqueous abyss has just been revealed. The most in-depth microbial analysis of the trench to date has turned up a new type of bacteria that munches on compounds similar to those found in oil. Scientists have never seen oil-chomping microorganisms before at these depths.
On that note, they have seen them before in different circumstances. However, the concentrations of this microbial plankton were found to be higher at the bottom of the Mariana Trench than anywhere else previously recorded on Earth. This could give us a new insight into how life exists and thrives at such depths – where the pressure is the equivalent of 1,091 kilograms (172 stone) being pressed against a fingernail.
One of the researchers, Jonathan Todd from the University of East Anglia (UEA) in the UK, said:
We studied the samples that were brought back and identified a new group of hydrocarbon-degrading bacteria. Hydrocarbons are organic compounds that are made of only hydrogen and carbon atoms, and they are found in many places, including crude oil and natural gas. So these types of microorganisms essentially eat compounds similar to those in oil and then use it for fuel. Similar microorganisms play a role in degrading oil spills in natural disasters such as BP’s 2010 oil spill in the Gulf of Mexico.
The researchers are interested in investigating how these bacteria feed so deep underwater – and maybe what feeds on them. Part of the study’s findings elaborates on where their food source – hydrocarbons – may be coming from. They believe it’s the pollution we’ve caused that is likely making its way into the trench.
Another one of the researchers from the team, Nikolai Pedentchouk from UEA, said:
We found that hydrocarbons exist as deep as 6,000 metres [19,685 feet] below the surface of the ocean and probably even deeper. A significant proportion of them probably derived from ocean surface pollution. To our surprise, we also identified biologically produced hydrocarbons in the ocean sediment at the bottom of the trench. This suggests that a unique microbial population is producing hydrocarbons in this environment.
The same sort of hydrocarbons the researchers were looking at have been spotted in algae on the ocean’s surface before, but they didn’t know they could be found way down there in the deepest parts of the ocean. The team was able to confirm through lab experiments that the bacteria could indeed consume hydrocarbons in extreme conditions. The research has been published in Microbiome.
What they plan to do next is gather more information on these microbes and where their food might be coming from, whether it’s natural or unnatural sources or both. They also want to explore more to find out if there are other types of bacteria that are able to feed on hydrocarbon compounds in the same way, which there probably are.
Lead researcher Xiao-Hua Zhang, from the Ocean University in China, said:
We know more about Mars than the deepest part of the ocean.
