Tree-planting rush overlooks climate benefits from natural forest recovery

Michael Taylor, Thomson Reuters Foundation

Posted at Sep 24 2020 04:26 AM

An aerial view shows part of the Mpanga Forest Reserve, a rainforest that is now regenerating after it was degraded by illegal loggers, farmers and villagers cutting down trees for firewood within Mpigi District, Uganda September 11, 2020. Asaph Kasujja, Reuters

KUALA LUMPUR - Leaving cleared tropical forests to regrow naturally has the potential to absorb a quarter of global carbon emissions from burning fossil fuels each year, researchers said on Wednesday.

A study led by the World Resources Institute (WRI), a US-based think-tank, looked at and mapped the potential carbon-storing benefits of letting cut forests recover on their own.

To meet national climate pledges, many countries have launched big tree-planting programs, signing up to high-profile schemes like the Bonn Challenge.

But some deforested areas in the tropics may benefit more from allowing them to regrow naturally - which is often cheaper and more likely to benefit native wildlife, the study said.

The approach could absorb 8.9 billion metric tons of carbon each year through to 2050 - much higher than previously thought, said WRI researchers.

That is on top of the carbon sponge already provided by existing forests, which absorb about 30 percent of planet-heating emissions, mainly generated by burning fossil fuels, each year.

Nancy Harris, research manager at Global Forest Watch (GFW), an online monitoring system hosted by WRI, said the key was to identify where forests can grow back and store carbon faster.

"Now we have a map that says 'go to the tropics because those areas will recover carbon the quickest'," she told the Thomson Reuters Foundation.

Cleared forest areas with the most carbon-storing potential when left to regrow are located in Brazil, Indonesia and Liberia, among others, she said.

Central Europe and the Middle East have the lowest rates for young forests to absorb carbon from the atmosphere, the study said.

In 2019, tropical rainforests - whose preservation is considered crucial to curbing climate change - disappeared at a rate of one football pitch every six seconds, according to GFW.

Environmentalists say conserving existing forests and restoring damaged ones reduces the risk of flooding, helps limit global warming by storing more carbon and protects biodiversity.

Published in the journal Nature, the study looked at cleared tropical forests that were unused but unable to return to their former state due to activities like sporadic logging or farming.

In some deforested areas in the tropics, such land could be utilized with incentives for local people to help the cleared forests grow back, said GFW research associate David Gibbs.

"Natural forest regrowth was probably previously under-appreciated as a natural climate solution," he added.

Harris noted that natural solutions like this were just "one tool in the toolbox" for tackling climate change.

"Reducing fossil fuels is also a very important aspect to this entire problem," she said.