Global warming has led to warming of the oceans which in turn has threatened the existence of many marine animals. However, a new study has presented a glimmer of hope after it found that microbes found in the ocean floor can absorb methane -a greenhouse gas that is largely responsible for warming up the planet.
Published in the Proceedings of the National Academy of Sciences journal, the study with a team of 10 scientists has revealed that microbes found in rocks underwater are more effective at absorbing methane. The team of scientists from Harvard University, California Institute of Technology, US Geological Survey Pacific Coastal and Marine Science Center, University of Southern California, Joint Genome Institute, found that microorganisms found in the carbonate rocks present in the ocean, like limestone and dolomite, can consume methane 50 times faster than microbes found in the sediments.
These methane sinks can help tackle the rising problem of global warming as greenhouse gas emissions continue to pollute the planet’s atmosphere. For their study, the scientists conducted a continental-scale survey of seven geologically diverse seafloor seeps. Their observation found that carbonate rocks from all sites hosted methane-oxidizing microbial communities with substantial methanotrophic potential.
Scientists also found that the carbonate rocks found underwater are unique in their formation which might contribute to their unique characteristic of consuming large quantities of methane. The study described the rocks as “chimney-like carbonates” that were extracted from the newly described Point Dume seep off the coast of Southern California. This rock exhibited the highest rates of anaerobic methane oxidation measured to date, found the study. After a thorough analysis of the rock that included physicochemical, electrical, and biological factors, the scientists attributed the substantial metabolic activity largely to higher cell density, mineral composition, kinetic parameters, and the presence of particular microbial lineages.
Leader of the team of scientists, Assistant Professor of Biology at Boston University, Jeffrey J. Marlow said that the chimneys exist in these rocks because some methane in fluid flowing out from the subsurface is transformed by the microbes into bicarbonate, which can then precipitate out of the seawater as carbonate rock. In a statement, senior author Peter Girguis, Professor of Organismic and Evolutionary Biology, Harvard University said that the microbes in these carbonate rocks are acting like a methane biofilter which consumes it all before it leaves the ocean.