New research claims burning forests could help save the planet

By Mark Waghorn via SWNS

Burning forests could save the planet, according to new research from Cambridge University.

Setting natural environments alight can increase carbon storage in the soil.

Prescribed ignitions actually locks in the greenhouse gas in temperate forests, savannahs and grasslands.

"Using controlled burns in forests to mitigate future wildfire severity is a relatively well-known process,"said first author Dr. Adam Pellegrini, of the University of Cambridge.

"But we have found that in ecosystems including temperate forests, savannahs and grasslands, fire can stabilize or even increase soil carbon."

"Most of the fires in natural ecosystems around the globe are controlled burns, so we should see this as an opportunity.

"Humans are manipulating a process, so we may as well figure out how to manipulate it to maximize carbon storage in the soil."

The finding in the journal Nature Geoscience points to a better method of manipulating the world's natural capacity for carbon capture.

It could boost ecosystems. Planting trees and suppressing wildfires are not necessarily the best option, said Dr. Pellegrini.

Fire burns plant matter and organic layers within the soil. Severe outbreaks leads to erosion and leaching of carbon.

It can take years or even decades for lost soil carbon to re-accumulate. But the study found fires can also cause other transformations within soils.

These can offset immediate losses - and may stabilize ecosystem carbon.

Fire creates charcoal, which is very resistant to decomposition, and forms 'aggregates.'

The physical clumps of soil protect carbon-rich organic matter at the center.

Fire can also increase the amount of carbon bound tightly to minerals in the soil.

"Ecosystems can store huge amounts of carbon when the frequency and intensity of fires is just right," saidDr. Pellegrini.

"It is all about the balance of carbon going into soils from dead plant biomass, and carbon going out of soils from decomposition, erosion, and leaching."

Frequent or intense fires in dense forests burn all the dead plant material that would otherwise decompose and release carbon into the soil.

They can also destabilize the soil, breaking off carbon-based organic matter from minerals and killing soil bacteria and fungi.

Without fire, soil carbon is recycled - organic matter from plants is consumed by microbes and released as carbon dioxide or methane.

But infrequent, cooler fires can increase the retention of soil carbon through the formation of charcoal and soil aggregates that protect from decomposition.

The scientists say ecosystems can also be managed to increase the amount of carbon stored in their soils.

Much of the carbon in grasslands is stored below-ground, in the roots of the plants.

Controlled burning, which helps encourage grass growth, can increase root biomass and therefore increase the amount of carbon stored.

"In considering how ecosystems should be managed to capture and store carbon from the atmosphere, fire is often seen as a bad thing," saidDr. Pellegrini.

"We hope this new study will show that when managed properly, fire can also be good - both for maintaining biodiversity and for carbon storage."

The study focused on carbon stored in topsoils, defined as those less than a foot deep.

"More carbon is stored in the world's soil than in the global vegetation and the atmosphere combined.

Natural fires occur in most ecosystems worldwide, making fire an important process in global carbon cycling.

The national parks of the Sierra Nevada Mountains have been using prescribed fire to thin forests for over a decade.

"Given 70 percent of global topsoil carbon is in fire-prone regions, using fire to promote soil organic matter stability may be an important nature-based climate solution to increase storage,"said Dr. Pellegrini.

The research was funded by the Gatsby Charitable Foundation which is committed to advancing knowledge in plant biology.