This article is from the In-Depth Report The Future of Climate Change

Peat and Repeat: Can Major Carbon Sinks Be Restored by Rewetting the World's Drained Bogs?

Bogs, swamps and mires help keep 500 billion metric tons of carbon out of the atmosphere, so preserving peatlands is emerging as a new priority

Courtesy of Global Forest Watch

The logging of palm trees grown atop the decaying peatlands of Borneo and Sumatra helps drive the economy of Indonesia, and this fact alone is starting to make the nation a top global priority for efforts to mitigate the warming climate. The problem is three-pronged: First, cheap pulp and paper produced in Indonesia winds up in the glossy coated products we know as junk mail, luxury shopping bags or children's books. Then, once the original trees are gone, palm oil plantations are often planted in their place. Finally, and most importantly from the perspective of the global climate, all of this is happening on top of peat—essentially dead plants that have remained wet under swampy conditions—which is drained as a result of all this activity. Globally, such degraded peatlands emit nearly three billion tons per year of carbon dioxide that was previously locked up in the decaying matter, or roughly 6 percent of all such greenhouse gas emissions from human activity.

"Peatlands only cover about 3 percent of the Earth but they accumulate more carbon than tropical rainforests," says biogeochemist Nancy Dise of Manchester Metropolitan University in England. "In terms of sitting there kind of quietly year after year packing away massive amounts of carbon, nothing tops these peatlands."

In fact, such peatlands store as much as 500 billion metric tons of carbon—or twice as much as is incorporated into all the trees in all the world's forests—roughly 1,450 metric tons of carbon per hectare. And the United Nations Environment Programme estimates that reducing global deforestation, especially that occurring on top of peatlands, could restore some 50 billion metric tons of CO2, or nearly two years of global emissions. Although peatlands do emit methane—a potent greenhouse gas—this is more than outweighed, in terms of the overall balance of greenhouse gases in the atmosphere, by the carbon dioxide they sequester.

Drainage of peatlands and their deforestation actually makes Indonesia the third-largest emitter of greenhouse gases in the world, behind China and the U.S. The country's emissions of CO2 from peat degradation—1.9 billion metric tons per year—are 1.5 times larger than those from all of its fossil fuel burning.

But with the world's growing demand for cheap paper products and thirst for palm oil, can the peatlands of Indonesia and far beyond be saved? And what will happen in the peatlands of Canada's far north as development of the unconventional fossil fuels known as tar sands takes off there?

In the bog
Belts of land where peat forms circle the globe in its boreal regions—in Canada and Russia, primarily, but also Alaska and Scandinavia. It also forms in the tropics—Indonesia, Brazil and the Congo—and in the far Southern Hemisphere where there is land—Chile, Argentina and various Southern Ocean archipelagos. The key is humidity, which is, of course, linked to the global climate and weather patterns. "Peat is conserved because of humid conditions," explains peat scientist Hans Joosten of the University of Greifswald in Germany. "Peatland is 95 percent water. This means that peat is wetter than milk but you can walk over it. It's the closest you can get to Jesus Christ."

That water is the key to the formation of the peat itself, which is a product of submerged plants that cannot be decomposed by microbes quickly. "Oxygen travels about 10,000 times slower in water than air. So the oxygen won't dissolve fast enough for the aerobic microbes to be able to use it to chew up all the organic carbon that's there," Dise says. But once that water is drained away, she adds, "the bugs that use oxygen have a party. They've got carbon, oxygen, they've got a few nutrients. They take carbon that's been sitting there for hundreds or thousands of years and they metabolize it, like you eating a ham sandwich. It turns into CO2."

And the primary thing humans do to peatlands is drain them, often by cutting canals—65 million hectares of peatlands worldwide have been transformed this way. In the Netherlands a millennia or more of drainage has taken land that ranged from five meters above to 10 meters below sea level and necessitated the development of such Dutch technologies as polders (low-lying patches of land encircled by embankments) and windmills to keep or pump the water out. In essence, ditches are cut into the peat in order to drain it for conversion to farmland, to float out logs or for other human activities. The peatland subsides and the ditches become shallower. To continue draining, the ditches have to be dug deeper and the cycle begins anew. "They call this the Devil's circle of peatland exploitation," Joosten notes, and it is occurring globally, including millions of hectares drained in Russia and Scandinavia to boost forest growth.

The other problem with drained peatlands is that they burn (peat can be used as a fuel directly and is often "mined" for that purpose). "If you have drained peat laying there and it is not water-saturated anymore, then it burns for months," Joosten says. And that's exactly what's happening from Belarus to Indonesia, billowing carbon dioxide into the atmosphere.

Peatlands for pulp, paper and palm oil
The peatlands of Borneo, Java, Sumatra and other islands of the Indonesian archipelago are central to the economic development of that country, from illegal loggers cutting canals to float out wood growing in peatlands to major pulp or palm oil concessions granted to international conglomerates. The peatlands are also among the last reservoirs of relatively untouched forest in the nation, where tigers live and other uncatalogued biodiversity still thrives. But the Indonesian government intends to at least double such development in the next decade, according to official figures.

The trees harvested from this land go into the pulp and paper mills, either for export directly to the U.S. and Europe or to China, where the pulp or paper is processed again into inexpensive paper products that are then also exported to the developed world. Much of the palm oil—a cooking oil but also a key ingredient in everything from cosmetics to cookies—gets shipped to Europe. "Just like China launders Indonesian pulp, Europe launders Indonesian palm oil," says Lafcadio Cortesi, forest campaign director at the Rainforest Action Network, a San Francisco–based environmental advocacy group.

Joosten adds that "as a result of palm oil, five times more CO2 is emitted [in Indonesia] than can be saved by burning biofuel in the West," even though the Netherlands, among other European countries, offers subsidies for burning more palm oil as fuel in power plants as part of its efforts to combat climate change. The UNEP estimates that burning palm oil releases three to nine times more CO2 than even burning coal.

"These areas are carbon gifts or carbon bombs," Cortesi says. "The pulp and paper industry and [the] palm oil industry are currently making them carbon bombs."

Climate change
It remains unclear what impact climate change will have on peatlands, though. When untouched, the ecosystems are relatively resilient to change thanks to shifting species composition and other feedback mechanisms that can help the peatland cope with changing conditions, Manchester's Dise says.

Plus, whereas warmer temperatures may encourage the release of more methane—an even more potent greenhouse gas—and drive drying of peatlands in some areas, it may also allow new peatlands to form in the northern latitudes. "In the north there is a lot of land that could sequester much more peat," Joosten notes. "It is not necessarily so that climate change could work out negatively for peatlands."

Efforts to reduce deforestation under a global climate treaty being negotiated in Copenhagen next week might also help prevent further loss of existing peatlands. "Any effective and affordable response to climate change should include preserving the world's remaining, carbon-rich old-growth forests," says Steve Kallick, director of the Pew Environment Group's International Boreal Conservation Campaign—including the vast northern forest that sits atop peatlands.

But what is sure is that human activity at present is largely working out negatively for peatlands, whether they are the ones transitioning to desert as a result of overgrazing in Mongolia or the 1.6 million hectares of boreal forest and peatlands in Canada that have been destroyed in pursuit of tar sands. In Alberta the development of such tar sand deposits of fossil fuel require the destruction of the overlying boreal forest and peatlands. A report from Global Forest Watch Canada estimates that the current destruction adds 8.7 million metric tons of CO2 to the atmosphere every year, in addition to the 36 million metric tons released by tar sands production directly.

"Keeping that carbon in place by protecting boreal forests is an important part of the climate equation," says climate scientist Andrew Weaver of the University of Victoria. "If you cut down the boreal forest and disturb its peatlands, you release more carbon, accelerating climate change."

Saving peatlands
Of course, Canadian provinces, including Ontario and Quebec, have protected nearly 130 million hectares of such boreal forest and peatlands, including the Hudson Bay Lowlands. Protecting all of the boreal forest in just Ontario would save 49 billion metric tons of carbon—or roughly 250 years of Canada's annual emissions of more than 202 million metric tons. All told, remaining boreal forests in Canada store some 208 billion metric tons of carbon—71 billion tons in the trees and 137 billion tons in the peat, or 26 years worth of global emissions from burning fossil fuels.

And U.S. companies ranging from PAK 2000—a New Hampshire–based packaging maker—to office supply chain store Staples have either cut ties with Indonesian pulp and paper producers or put in place voluntary safeguards to eliminate procurement from such places. U.S. paper companies have also filed a dumping complaint with the U.S. Department of Commerce objecting to cheap Indonesian pulp and paper products.

Of course, similar livelihoods would need to be found for developing countries such as Indonesia and the developed countries of the world largely became affluent doing the kinds of things—such as draining peatlands—they are now trying to prevent. "The Netherlands has gained its prosperity because of peat," Joosten notes.

But the Netherlands is part of a new effort to actually rewet some of the drained peatlands and thus restore them to function as carbon sinks, an effort covering thousands of hectares in Europe and the U.K. and even Indonesia, although not draining them in the first place is a lot easier than rewetting a canal-strewn landscape. "We are not able to rewet the centers of these mini domes in Indonesia," notes Joosten, who is involved in many of the rewetting projects. "You can only rewet a small part by damming the canals." Even the U.S. Geological Survey has similar projects to create "carbon farms" by increasing such wetlands in the Sacramento–San Joaquin River Delta in California.

But if drainage is reduced or reversed, already drained peatlands continue to decompose and emit carbon dioxide. "Even if you reduce the rate of peatland drainage, you still increase the emissions from peatland drainage," Joosten says. "It's not only the ones draining now but also peatlands you have drained before. It is a cumulative process."

Plus, in an effort to prepare for looming regulations on greenhouse gases, peatland deforestation and drainage is actually being accelerated by everyone from villagers to major companies so that, in the future, such areas can make sure they have enough degradation to qualify for any funds made available down the line to prevent further damage.

Perhaps preserving peatlands in the first place should be a priority. "The peatlands are keeping us from a lot of trouble, storing a massive amount of carbon for us," Dise says. "Anything we can do to mitigate or lessen or halt the loss of those peatlands we should do. That means stopping converting them to plantations for things like rice or oil palms."

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