News / Asia

Coastal Trees Help Fight Global Warming

Mangroves found to store more planet-warming carbon dioxide than previously thought

A tall mangrove forest on the island of Borneo. Mangroves often reside on thick sediment layers rich in organic matter, resulting in carbon storage exceeding most tropical forests.
A tall mangrove forest on the island of Borneo. Mangroves often reside on thick sediment layers rich in organic matter, resulting in carbon storage exceeding most tropical forests.

Multimedia

Audio

A new study says the world's tropical coastal forests store more planet-warming carbon dioxide than almost any other ecosystem.

But rapid loss of these forests - known as mangroves - is releasing substantial and previously unrecognized quantities of greenhouse gases into the atmosphere.

Mangroves provide rich breeding grounds for fish, and they help buffer coastal areas from storm surges. But their role in trapping climate-warming carbon dioxide has not been studied much.

A new study in the journal "Nature Geoscience" provides a first look.

More carbon per hectare than tropical rainforests

Daniel Donato with the Forest Service of the U.S. Department of Agriculture and his colleagues surveyed tree mass, dead wood, and soil carbon in 25 mangrove ecosystems around the tropical Indian and Pacific Oceans.

A mangrove landscape on the Ganges River Delta, Bangladesh. Mangroves are being rapidly deforested globally.
A mangrove landscape on the Ganges River Delta, Bangladesh. Mangroves are being rapidly deforested globally.

Donato says study shows, "They are right up there with the most carbon-rich forests in the world."

Donato's results showed mangroves store about three to four times more carbon per hectare as temperate forests or even tropical rainforests. But Donato says most of it is hidden.

"Carbon in mangroves is really about the below-ground story," he says. "Most of the carbon stored in that ecosystem is in the soil and the tree roots."

Mangroves stored about five times as much carbon in deep soils compared to temperate or tropical forests.

Rapid loss

But the researchers note that a third to a half of the world's mangroves have been cut down in the last half-century for timber, coastal development and aquaculture.

The researchers estimate that the amount of greenhouse gases released each year from mangrove deforestation may be equivalent to as much as 10 percent of the global toll from deforestation.That's despite the fact that mangroves make up less than 1 percent of the tropical forest area.

Donato says the research should get the attention of policymakers."It shows mangroves are probably pretty good candidates for things like carbon-market trading to encourage sustainable forest management."

Dollar value

Carbon markets, where industries buy the right to emit carbon dioxide in exchange for protecting forests or other offsets, could be a powerful force for conservation, environmentalists say.

Many developing countries, especially in Asia, are clearing mangroves for fish and shrimp aquaculture because it can be profitable. The value of the mangrove often is not immediately obvious to policymakers, says Emily Pidgeon, director the marine climate change program at the environmental group Conservation International.

"By suddenly having an actual mechanism to value these systems in dollars, it gives you a potentially very large new mechanism for countering the other financial and economic arguments," she says.

Consumer standards

Other groups are approaching the economics of mangrove conservation from the buyer's side. They are encouraging Western supermarkets and other large consumers to only buy farmed seafood that meets certain standards, including limited impact on mangrove loss.

Pidgeon says it works well in some places. But other developing countries are not equipped to meet or enforce the standards.

"The government structures are not very strong," she says, "and the expertise and capacity to apply some of these approaches is often very challenging."

Mosaic of services

One of the most important ways to help local communities value the mangroves, Pidgeon says, is to see them as part of a mosaic that provides a whole range of services, including nurturing the fisheries that many developing-world coastal fishing communities depend on for their livelihoods.

"Although you may catch your fish in one particular piece of the mosaic, the fish are only there to catch because of the time they spend in all the other pieces," she adds.

For many coastal communities, carbon storage is just the latest service they may see mangroves providing.

You May Like

Video One Year After Thai Coup, No End in Sight for Military Rule

Since carrying out the May 22, 2014 coup, the general has retired from the military but is still firmly in charge More

Goodbye, New York

This is what the fastest-growing big cities in America have in common More

Job-Seeking Bangladeshis Risk Lives to Find Work

The number of Bangladeshi migrants on smugglers’ boats bound for Southeast Asian countries has soared in the past two years More

This forum has been closed.
Comments
     
There are no comments in this forum. Be first and add one

Featured Videos

Your JavaScript is turned off or you have an old version of Adobe's Flash Player. Get the latest Flash player.
Turkey's Main Opposition Party Hopes for Election Breakthroughi
X
May 22, 2015 10:23 AM
Turkey’s main opposition Republican People’s Party has sought an image change ahead of the June 7 general election. The move comes after suffering successive defeats at the hands of the Islamist-rooted AK Party, which has portrayed it as hostile to religion. Dorian Jones reports from the western city of Izmir.
Video

Video Turkey's Main Opposition Party Hopes for Election Breakthrough

Turkey’s main opposition Republican People’s Party has sought an image change ahead of the June 7 general election. The move comes after suffering successive defeats at the hands of the Islamist-rooted AK Party, which has portrayed it as hostile to religion. Dorian Jones reports from the western city of Izmir.
Video

Video Europe Follows US Lead in Tackling ‘Conflict Minerals’

Metals mined from conflict zones in places like the Democratic Republic of Congo are often sold by warlords to buy weapons. This week European lawmakers voted to force manufacturers to prove that their supply chains are not inadvertently fueling conflicts and human rights abuses. Henry Ridgwell reports from London.
Video

Video Class Tackles Questions of Race, Discrimination

Unrest in some U.S. cities is more than just a trending news item at Ladue Middle School in St. Louis, Missouri. As VOA’s Kane Farabaugh reports, it’s a focus of a multicultural studies class engaging students in wide-ranging discussions about racial tensions and police aggression.
Video

Video Mind-Controlled Prosthetics Are Getting Closer

Scientists and engineers are making substantial advances towards the ultimate goal in prosthetics – creation of limbs that can be controlled by the wearer’s mind. Thanks to sophisticated sensors capable of picking up the brain’s signals, an amputee in Iceland is literally bringing us one step closer to that goal. VOA’s George Putic reports.
Video

Video Afghan Economy Sinks As Foreign Troops Depart

As international troops prepare to leave Afghanistan, and many foreign aid groups follow, Afghans are grappling with how the exodus will affect the country's fragile economy. Ayesha Tanzeem reports from the Afghan capital, Kabul.
Video

Video Poverty, Ignorance Force Underage Girls Into Marriage

The recent marriage of a 17-year old Chechen girl to a local police chief who was 30 years older and already had a wife caused an outcry in Russia and beyond. The bride was reportedly forced to marry and her parents were intimidated into giving their consent. The union spotlighted yet again the plight of many underage girls in developing countries. Zlatica Hoke reports poverty, ignorance and fear are behind the practice, especially in Asia and Africa.
Video

Video South Korea Marks Gwangju Uprising Anniversary

South Korea this week marked the 35th anniversary of a protest that turned deadly. The Gwangju Uprising is credited with starting the country’s democratic revolution after it was violently quelled by South Korea’s former military rulers. But as Jason Strother reports, some observers worry that democracy has recently been eroded.
Video

Video California’s Water System Not Created To Handle Current Drought

The drought in California is moving into its fourth year. While the state's governor is mandating a reduction in urban water use, most of the water used in California is for agriculture. But both city dwellers and farmers are feeling the impact of the drought. Some experts say the state’s water system was not created to handle long periods of drought. Elizabeth Lee reports from Ventura County, an agricultural region just northwest of Los Angeles.
Video

Video How to Clone a Mammoth: The Science of De-Extinction

An international team of scientists has sequenced the complete genome of the woolly mammoth. Led by the Swedish Museum of Natural History in Stockholm, the work opens the door to recreate the huge herbivore, which last roamed the Earth 4,000 years ago. VOA’s Rosanne Skirble considers the science of de-extinction and its place on the planet
Video

Video Blind Boy Defines His Life with Music

Cole Moran was born blind. He also has cognitive delays and other birth defects. He has to learn everything by ear. Nevertheless, the 12-year-old has had an insatiable love for music since he was born. VOA’s June Soh introduces us to the young phenomenal harmonica player.

VOA Blogs