Microbes may act as gatekeepers of Earth's Deep Carbon

[Judi Lynn]

Date:
April 24, 2019
Source:
University of Oxford

This groundbreaking study, published in Nature, shows that microbes consume and -- crucially -- help trap a small amount of sinking carbon in this zone. This finding has important implications for understanding Earth's fundamental processes and for revealing how nature can potentially help mitigate climate change.

At a subduction zone there is communication between Earth's surface and interior. Two plates collide and the denser plate sinks, transporting material from the surface into Earth's interior. Showing that the microbes at the near-surface are playing a fundamental role in how carbon and other elements are being locked up into the crust provides a profound new understanding of Earth processes and helps researchers model how Earth's interior may develop over time.

Co-author, Professor Chris Ballentine, Head of the Department of Earth Sciences at the University of Oxford, said: 'What we've shown in this study is that in areas that are critically important for putting chemicals back down into the planet -- these big subduction zones -- life is sequestering carbon. On geological timescales life might be controlling the chemicals at the surface and storing elements like carbon in the crust.'

This is the first evidence that subterranean life plays a role in removing carbon from subduction zones. It has been well established that microbes are capable of taking carbon dissolved in water and converting it into a mineral within the rocks. This study demonstrates that the process is happening on a large scale across a subduction zone. It is a natural CO2 sequestration process which can control the availability of carbon on Earth's surface.

More:
https://www.sciencedaily.com/releases/2019/04/190424153544.htm