The Peat Report: Breaking Down Bog Restoration
In addition to harvesting peatland, producers are responsible for returning them to functioning ecosystems. Learn more about the seven steps they take in restoring peatlands.
October 21, 2010
The Bois-des-Bel peatland in Quebec, Canada, serves as a 27-acre outdoor laboratory where researchers have spent the last decade fine-tuning restoration techniques.
Behind door number one of that outdoor laboratory is a narrow strip of land - a control experiment - that shows exactly what happens when peatlands are abandoned after years of harvesting. Twenty years since Bois-des-Bel harvesting was completed and another 11 years since it became a project site, little vegetation is present on that abandoned control strip. Among the vegetation present are a few invasive plants. Add in the fact that peat is not reaccumulating because the strip is not wet enough, and this Bois-des-Bel control area offers a glimpse at what our world would be like if peatlands were not being restored.
Behind door number two at Bois-des-Bel is a completely different world - a peatland full of vegetation and one that's redeveloped the sphagnum peat mosses that are necessary to sequester carbon from the atmosphere. To a peat industry outsider, the restored peatland has the look of a peatland untouched by mankind. And, according to peat industry insiders, Bois-des-Bel is a classic example of a harvested peatland once again becoming a fully functional ecosystem.
"Sphagnum peat mosses are some of the most efficient organisms we have here on the planet to sequester carbon," says Line Rochefort, the senior chair of the Industrial Research Chair in Peatland Management at Université Laval in Quebec. "So we feel it's important to have a responsible management strategy. Once you finish harvesting peat, it's important to restore so you have a functioning ecosystem that will fulfill ecological services provided by peatlands."
The Ecosystem Is Everything
Restoring a functional ecosystem is not an overnight process, though. In fact, it can take several years. But because researchers have invested their time and peat producers have been proactive in their commitments to restore peatlands they've previously harvested, restoration is now common practice in Canada.
The peat industry, however, believes few people are aware of the extent to which restoration takes place. So despite the competitive nature of their businesses, producers work together with groups like the Canadian Sphagnum Peat Moss Association and the Quebec Peat Moss Producers Association to reach their restoration goals.
"We're a very small industry by the standards of a big industry," says Clarence Breau, vice president for Sun Gro Horticulture's east region. "The best way to have success is to stick together. We may fight like cats and dogs in the marketplace, but restoration is a common goal the industry has because we want to protect our industry.
"The only thing we may not have done enough of is to promote the work we've done so far with the environment and the restoration of peatlands. We do have growers visit our operations, and we show them how we harvest and produce our product. We show them the care we take putting it into the bag and having the right quality. But very seldom do we show our restoration bogs."
Adds Valerie Berger, the corporate director of sales and marketing at Berger Peat Moss: "As we move on, more emphasis will be put on sharing and showing our bog restoration practices."
A peatland restoration effort actually involves seven steps: 1) preparation of peat fields; 2) creation of pools; 3) gathering of plant material from a borrow area; 4) spreading of plant material; 5) spreading of mulch; 6) fertilizing with phosphate; and 7) blocking drainage.
The creation of pools is an optional step, but it's one researchers took at Bois-des-Bel to increase the water supply for wildlife. A low phosphate fertilization can be used to facilitate the establishment of mosses and vascular plants.
But before pools are created and phosphate is applied, a peat field's surface needs a refresher in order to redistribute water and rewet the site. Once peatlands are leveled and berms are built, plant material needs to be gathered to replenish the restoration site.
"If you just abandon the site, plants don't recolonize by themselves," Rochefort says. "You can go to an offsite place to collect the material or gather the material somewhere on site."
Université Laval, for example, has been operating a sphagnum farm in New Brunswick since 2004, and any producer in need of plant material for restoration has access to it. One of the most challenging parts of gathering material, however, is transporting it. Rochefort says it's the biggest cost of the restoration process. But spreading the plant material and straw mulch is important, too.
"You need to protect the plant material from drought and frost heaving, and we do that by using a straw mulch," Rochefort says. "Straw mulch creates a nice microclimate."
The last restoration step, blocking drainage, is vital so water sits on the peatland and sphagnum mosses return. After only a few years, a peatland's vegetative surface will return and mirror the peatland that originally existed. The accumulation of peat will also ensue.
"Before peat accumulates the sphagnum carpet has to be established," says Jacques Gagnon, Premier Tech Horticulture's peatland restoration director. "After that, there will be a portion of the fiber that will die and accumulate the peat. Usually, you'll see 1 millimeter accumulate per year.
We want to make sure the land returns to a functioning wetland, that the surface looks as it once did and so the surface can absorb carbon."