Microbes Make the Best Climate Engineers

With the rising threat of global warming, you’d think humans are the best (or worst) climate engineers to arrive on planet Earth. But you’d be wrong. Tiny microbes have been modifying our climate for billions of years, and unless we learn how to work with them, we could be fighting a losing battle to get our greenhouse emissions under control.

For example, humans release tremendous amounts of methane into the atmosphere. But we do this indirectly through our livestock, rice fields and landfill. In each of these situations, it’s actually microbes producing the methane that makes such a potent greenhouse gas. We just give the microbes the environment they need to make the stuff.

In fact, unless we deeply understand how these microbes do their work, we might be fighting a losing battle to control climate change. This is based on a commentary published in the February 2008 issue of Microbiology Today. The article was written by Dr Dave Reay from the University of Edinburgh.

Much of the carbon cycle in the world involves the oceans, which breath carbon dioxide in and out of the atmosphere. But once again, it’s microbes which are taking in carbon from the atmosphere and releasing it again.

The trick, of course, is to learn how to work with them. If scientists can better understand the processes that go on, they could encourage microbes to pull more carbon out of the atmosphere, or break up methane generated in landfills. Plankton are already being used as feedstock for some biofuels, and cyanobacteria could provide hydrogen fuel.

For example, the wetlands of the Earth dump 100 million tonnes of methane into the atmosphere every year. This number would be much higher, but a significant amount is used by methanotropic bacteria before it can escape into the atmosphere. Compare this to the 150 million tonnes delivered directly to the atmosphere by human methods, like rice cultivation.

As we warm the planet, we don’t know what impact microbes might play to slow, or maybe even accelerate our actions.

“The impact of these microbially-controlled cycles on future climate warming is potentially huge,” says Dr Reay. “Microbes will continue as climate engineers long after humans have burned that final barrel of oil. Whether they help us to avoid dangerous climate change in the 21st century or push us even faster towards it depends on just how well we understand them.”

Original Source: Microbiology Today