Quantcast
Climate
A team from Greenpeace Africa has been studying tropical peatland near Lokolama. Kevin McElvaney / Greenpeace

Climate Change and Deforestation Threaten World’s Largest Tropical Peatland

By Daisy Dunne

Just over a year ago, scientists announced the discovery of the world's largest intact tropical peatland in a remote part of the Congo's vast swampy basin.

The Cuvette Centrale peatlands stretch across an area of central Africa that is larger than the size of England and stores as much as 30 billion tonnes of carbon.


Now, the same research team has published a new study finding that future climate change, along with deforestation, could threaten the peatlands' ability to soak up and store large amounts of carbon.

If left unaddressed, these threats could cause the Congo peatlands to turn from a carbon sink into a carbon source, the study says. This means that the peatlands could contribute to climate change by releasing more carbon than they are able to absorb.

Protecting the peatlands from climate change will require "an international effort to reduce greenhouse gas emissions," the lead author told Carbon Brief.

Peat Power

The Cuvette Centrale, which spans both the Republic of the Congo and the Democratic Republic of Congo (DRC) (see map below), is the second-largest tropical wetland in the world.

Location of the Cuvette Centrale wetlands in Africa (in green)Dargie et al (2017)

The peatlands within the Cuvette Centrale covers 145,500 sq km and contains 30 percent of the world's tropical peatland carbon, according to the 2017 Nature paper. This is equivalent to about 20 years' worth of U.S. CO2 emissions from burning fossil fuels.

Across the world, peat covers just 3 percent of the land's surface, but stores one-third of the earth's soil carbon.

Peat is a wetland soil made of partially decomposed plant debris. It is usually found in cooler, waterlogged environments, explained Dr. Greta Dargie, a research fellow from the University of Leeds and lead author of the study published in the journal Mitigation and Adaptation Strategies for Global Change. She told Carbon Brief:

"Under waterlogged conditions, the usual decomposition of dead trees and leaves is slowed, meaning there is a build-up of carbon-rich material which we call peat. A long slow build-up means that peatlands store enormous quantities of carbon."

Future climate change presents one of the largest threats to the Congo peatlands, the new study finds.

The latest assessment report (pdf) from the Intergovernmental Panel on Climate Change (IPCC) finds that the region could warm by around 0.5°C from 2000 to the end of the century under a low-emissions scenario (RCP2.6) and by 4.5°C under a high-emissions scenario (RCP8.5).

It is less clear how global warming could affect rainfall in the region, but research (pdf) suggests that the peatlands could experience an overall reduction in rainfall and an increase in the number of dry periods as the climate warms.

A combination of less rainfall and higher temperatures could cause parts of the peatlands to dry out, which could reduce the rate of plant decomposition and, therefore, the rate that the peatlands can absorb carbon from the atmosphere.

Drier conditions could also prompt the peatlands to start releasing larger amounts of carbon, said professor Simon Lewis, a study author from the University of Leeds and University College London, and one of Carbon Brief's contributing editors. He told Carbon Brief:

"The critical insight here is that the central Congo peatlands are probably maintained by rainwater. So, even modest reductions in dry season water-logging, perhaps through rising temperatures and increasing evaporation rates, would mean the whole system moves from a carbon sink to a carbon source."

In other words, climate change could cause the Congo peatlands to start releasing more carbon into the atmosphere than it is able to absorb.

Forest Under Threat

Another threat to Congo's peatlands could come from a potential rise in deforestation for wood and palm oil production in the region, the study notes.

The removal of trees from above peatlands can leave large areas of ground exposed to the sun, which can cause the boggy ground to dry out. This can cause the peatlands to release carbon at a faster rate.

At present, government officials from the DRC have granted logging access to 20 percent of the forested peatlands. The extent of the logging concession agreements (red outlines) is shown on the chart below, where dark grey indicates peatland and light grey shows other types of land cover.

At least one concession agreement (shown in shaded red) has also been approved for the construction of an oil palm plantation in the Republic of the Congo part of the peatlands, which would take up 4,200 sq km of forested peatlands.

Extent of logging concessions (red outlines) and oil palm concessions (shaded red) granted in the Cuvette Centrale. Dark grey shows the location of the Cuvette Centrale peatlands, while light grey shows other types of land cover. Dargie et al. (2018)

Despite these agreements being reached, logging operations are yet to commence in the peatland forests. This is likely to be because the DRC introduced a national ban on logging in 2002, the study notes.

However, the country's government is currently considering lifting this ban, which would mean logging could be permitted across large areas of the peatland region.

Plans to lift the ban are being driven forward by the French Development Agency (AFD) with financial support from the Norway-led Central African Forests Initiative (CAFI), Lewis said. These groups argue that lifting the ban could aid social development in the region and make it easier to curb illegal and unregulated deforestation.

On top of this, the peatlands could also be affected by plans to construct hydroelectric dams in region, including the Grand Inga hydropower project. Such projects could divert water away from the wetlands, the study notes.

Overall, the peatlands face an immediate risk from deforestation and land-use change and a more long-term threat from climate change, Lewis said:

"The competing threats of direct land-use change and climate change are difficult to compare. The speed with which land can be converted is fast and can quickly kill large areas of swamp forest. But other areas would probably remain unaffected. The speed of climate change is slower than the movement of bulldozers, but could affect the entire peatland."

Protecting Peat

To protect the peatlands in the short term, policymakers should consider introducing new environmental protections to the region, the authors wrote in their paper:

"Further research, therefore, needs to integrate knowledge from local communities, the natural sciences and social sciences, to develop a more holistic understanding of the Cuvette Centrale peatlands and facilitate local communities and their governments to manage and protect this globally significant region."

However, protecting the peatlands from the threat of climate change will require a long-term "international effort," Dargie said:

"With climate change, there is also the added complication that Republic of the Congo and DRC government policies and interventions alone will not be enough to avoid any negative impacts on the Congo Basin peatlands. That will require an international effort to reduce greenhouse gas emissions."

Reposted with permission from our media associate Carbon Brief.

Show Comments ()

EcoWatch Daily Newsletter

Sponsored
Politics
Jess Lundgren / CC BY 2.0

The Trump Administration’s ‘Dishonest’ Attack on Fuel-Economy Standards

By John R. Platt

The Trump administration's plan to freeze fuel-economy standards is "the most spectacular regulatory flip-flop in history," said a retired EPA engineer who helped to develop new the standards under the Obama administration.

Keep reading... Show less
Adventure
Lizzie Carr traveling down the Hudson River on her stand-up paddleboard. Max Guliani / The Hudson Project

Her Stand-Up Paddleboard Is a Platform for Campaigning Against Plastic Pollution

By Patrick Rogers

Lizzie Carr was navigating a stretch of the Hudson River north of Yonkers, New York, recently when she spotted it—a hunk of plastic so large and out of place that she was momentarily at a loss to describe it.

Keep reading... Show less
Science
The Ross Ice Shelf at the Bay of Whales. Michael Van Woert, NOAA

Scientists Study Ice Shelf by Listening to Its Changing Sounds

By Marlene Cimons

Researchers monitoring vibrations from Antarctica's Ross Ice Shelf were flabbergasted not long ago to hear something unexpected—the ice was "singing" to them. "We were stunned by a rich variety of time-varying tones that make up this newly described sort of signal," said Rick Aster, professor of geosciences at Colorado State University, one of the scientists involved in the study.

Keep reading... Show less
Politics
DSLRVideo.com / Flicker / CC BY-SA 2.0

'Go Out and Vote' Patagonia Endorses Candidates For First Time in Its History

Outdoor brand Patagonia is endorsing candidates for the first time in its history in an effort to protect the country's at-risk public lands and waters.

The civic-minded retailer is backing two Democrats in two crucial Senate races: the re-election of Sen. Jon Tester of Montana; and Rep. Jacky Rosen, who is trying to unseat Republican Sen. Dean Heller in Nevada.

Keep reading... Show less
Sponsored
Animals
Desert Bighorn Sheep in Joshua Tree National Park. Kjaergaard / CC BY 3.0

Leaked Trump Administration Memo: Keep Public in Dark About How Endangered Species Decisions Are Made

In a Trump administration memorandum leaked to the Center for Biological Diversity, the U.S. Fish and Wildlife Service is directing its staff to withhold, or delay releasing, certain public records about how the Endangered Species Act is carried out. That includes records where the advice of career wildlife scientists may be overridden by political appointees in the Trump administration.

Keep reading... Show less
Popular
Disposable diapers add staggering amounts of waste to landfills. Pxhere

Dirty Diapers Could Be Recycled Into Fabrics, Furniture Under P&G Joint Venture

Disposal diapers can take an estimated 500 years to decompose. That means if Henry VIII wore disposables, they'd probably still be around today.

Although throwaway nappies are undoubtedly convenient, these mostly-synthetic items cause never-ending steams of waste that will take centuries to disappear.

Keep reading... Show less
Sponsored
Popular
The swelling barrier lake after a landslide forced evacuations along the Yarlung Zangbo River. YouTube screenshot / CCTV+

6,000 Evacuated After Tibet Landslide

Six thousand people have been evacuated after a landslide in Tibet Wednesday blocked a river that flows downstream into India, creating a lake that could cause major flooding in the subcontinent once the debris is cleared, The Associated Press reported.

Chinese emergency officials announced the evacuations Thursday. The landslide impacted a village in Menling County, but no one was killed or injured, Chinese officials said.

Keep reading... Show less
Climate
Pexels

Carbon Capture: What We Don’t Talk About When We Talk About Climate Change

By Daniel Ross

The latest Intergovernmental Panel on Climate Change (IPCC) report lays out a rather grim set of observations, predictions and warnings. Perhaps the biggest takeaway? That the world cannot warm more than 1.5 degrees Celsius (1.5°C) over pre-industrial levels without significant impacts.

Keep reading... Show less
Sponsored

mail-copy

The best of EcoWatch, right in your inbox. Sign up for our email newsletter!