TUDU, EstoniaWhat
looks like a typical Northern European forest of scrubby Scotch pine,
blueberry bushes, and ferns, about 15 miles inland from the Baltic Sea,
turns out on closer inspection to be a peat bog—one
that’s been drained and mined. A 10-foot-deep drainage ditch, now
covered in foliage, still fills every time it rains. Furrows reveal
where heavy equipment cut the peat into rectangular blocks, about the
size of toaster ovens, which were dried and later burned in homes
throughout the former Soviet Union.
“We are taking measurements to plan how big the dams are that we need,” he says, hopping into the ditch and plunging a five-foot long wooden stick into the neon-green muck. “The ditch is already covered with sphagnum moss and tussocks of cotton grass. If we get the water higher, there is a good potential these species will spread out and make it suitable for conservation.”
“We are taking measurements to plan how big the dams are that we need,” he says, hopping into the ditch and plunging a five-foot long wooden stick into the neon-green muck. “The ditch is already covered with sphagnum moss and tussocks of cotton grass. If we get the water higher, there is a good potential these species will spread out and make it suitable for conservation.”
Along with a group of Estonian environmental scientists,
Salm, a stocky ex-graduate student now at the forefront of environmental
policy here, is hoping to restore this bog to what it looked like
before the 50 years of Soviet rule that ended in 1991. During that
occupation, thousands of peat bogs across Estonia were drained, leaving
an opening for forest trees and shrubs.
While that might seem like a good thing, the problem is that
these old peat bogs are leaking greenhouse gases—nearly 8 million
metric tons per year of carbon dioxide, according to a 2015 report by the Nordic Council of Ministers. That’s more carbon emissions than all of Estonia’s cars and trucks combined.
The CO2 comes from the thick layers of peat, mostly dead
sphagnum moss, that is preserved in bogs by the wet conditions and by
chemicals contained in the sphagnum, both of which suppress bacterial
decomposition of the organic matter. When bogs dry out, the cap of
living sphagnum dies, and bacteria start rapidly digesting the organics
below. That turns the bog from a CO2 sink into a copious source.
Turning back the clock is simple in principle, says Salm: You just close the drainage ditches, so that rainwater and snowmelt raise the water table back to the surface. Then you allow sphagnum and other native plants to recolonize the marshy ground. This year, with $8 million in funding from the European Union, Estonia is hoping to restore more than 50,000 acres of abandoned bogs at 89 sites. If successful, the “LIFE Mires” project will be scaled up to abandoned peatlands in Latvia, Lithuania, Germany, and Poland.
For other countries, cutting carbon emissions over the next
few years might mean switching from coal to natural gas power plants,
driving clean electric cars or installing solar panels on rooftops. But
for tiny Estonia, home to only 1.3 million people, it means restoring
the peatlands that cover nearly one-quarter of the landscape.
To Salm and other scientists here, bringing back the bogs is
an environmental two-for-one: it shrinks Estonia’s carbon footprint,
and it creates new habitat for rare bog creatures like the Western
capercaillie (Tetrao urogallus) and the moor frog (Rana arvalis).
“When we restore these areas, we keep carbon in the soil and
recreate conditions so that carbon is absorbed,” says Salm. “But these
bogs are also habitats for certain plants and animal species that live
nowhere else.”
Old Industry, New Trick
The 457 residents of Lavassaare are a living legacy of
Estonia’s four-century-old peat-harvesting industry. Homes and apartment
buildings are heated with peat burned in a bio-energy plant operated by
Tootsi Turvas, the country’s largest peat company. An old peat-hauling
narrow-gauge railway line runs through the center of town. The
Soviet-era train was running until three years ago, when tensions with
Russia made it impossible to get replacement parts. There’s even a museum with black-and-white photos of horse-drawn wagons carrying blocks of hand-cut peat.
Tiit Saarmets started work at Tootsi Turvas in 1987, when it
was Estonia’s state-owned peat enterprise. He’s close to retirement now
and is the Finnish-owned firm’s environmental manager. He takes me on a
tour of the vast commercial peat harvesting area—nearly 10 square miles
of dirt-brown fields.
The harvesting process takes several steps. In the fall,
excavators remove the surface vegetation and cut the top layer of
sphagnum moss into blocks. Stacks of the dun-colored blocks freeze and
dry in the winter. In spring they thaw and are shipped for use in garden
beds and as insulation.
Removing the top few feet of sphagnum exposes the ancient,
dark-brown peat soil underneath—the result of twelve thousand years of
accumulated organic material decomposing in an acidic and oxygen-starved
environment. As the peat accumulates, it sucks up water and expands. To
harvest it, the bogs are drained. Specially designed tractors roll over
the surface on buoyant balloon tires, sucking up the dark soil with
giant vacuum cleaners.
The peat is dried, packaged, and shipped to the rest of
Europe as fertilizer. Some of it gets compressed into briquettes and
sold as a fuel to a few Estonian communities. Tootsi has been working
this site since the 1970s, and there’s enough peat to last another 10
years.
“After that we finish, close it, and start to recultivate,” Saarmets says.
Just across an embankment from the production area, in one
part of the sprawling complex, company officials have blocked drainage
ditches and begun to let nature take its course. It’s a slow process.
Saarmets shows me one place where restoration began about three years
ago. Only a few sparse patches of sphagnum moss cover the bare dirt.
Nature Needs Help
Europe’s commercial peat industry is watching Estonia’s
EU-sponsored bog restoration project with wary support. Peat is big
business: Holland’s global flower industry, for example, relies on
Estonian peat. But in recent years some green groups have called for a
boycott on peat, saying the harvesting contributes to global warming.
“The customers want us to be more environmentally friendly,”
says Elar Asram, site manager for Kraver AS, a Belgian-owned firm based
in Estonia. Asram worries about new environmental regulations in
Estonia that kick in by 2019. Just like strip mines for coal in the
United States, Kraver, Tootsi and other firms will have to reclaim the
peatlands once they finish harvesting.
“We have to restore all the areas,” Asram tells me in his office near the Tassi bog production area. “But how is the big question.”
The answer, says Edgar Karofeld, an ecologist at the
University of Tartu, is that it isn’t enough just to let nature take its
course. Since 2012 Karofeld and a team of students have been restoring a
10-acre plot adjacent to Kraver’s commercial harvest area. They’ve
taken care to keep the water table high—but instead of relying on
sphagnum to colonize the restored area on its own, they’ve carefully
transplanted the moss from other protected areas.
“Now there are 100 percent bog species here,” says Karofeld during a visit to the site. “If you do it correctly, you can good results after three years. It depends on how much rain you have during the summer.”
Karofeld’s team have sunk PVC cylinders into the squishy peatland and
covered them with glass chambers to measure the flux of greenhouses
gases. Emissions of methane rise slightly as the water returns, they
find. But in places where the sphagnum returns quickly, emissions of all
three greenhouse gases combined—CO2, nitric oxide, and methane—go down.
“Some of our restoration areas are already a sink for carbon,” Karofeld says.
Bog Trailblazer
Estonia’s big ambition make it an ecological trailblazer, but it’s
not the only country restoring bogs. Scientists from Canada and other
Baltic nations are also experimenting with the process. It’s one of
trial and error, says Marku Lamp, who oversees Estonia’s restoration
project as the government’s deputy secretary of conservation.
At Viru bog, the closest nature area to Tallinn, the capital, and a
popular spot for busloads of foreign tourists, a three-year restoration
failed because dams weren’t built correctly. There wasn’t enough water
to keep the mosses wet.
“We are learning from our mistakes,” Lamp says. “We can share our
experiences to find the best solutions.” But he and his colleagues are
starting with one crucial advantage. “Estonia is a very wet country,”
says Lamp.
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