Plastic bottles and bags, car emissions, meat-eating – all are well known as major contributors to climate change. But outside the scientific community, less is understood about peatlands and the enormous impact they can have on our future.
The landscapes of vegetation decomposing into dense brown soil known as peatlands comprise just 3 percent of the global land surface, and yet they store the world’s largest terrestrial carbon stocks, making their restoration and preservation vital in the fight against climate change.
The World Resource Institute (WRI) estimates that every hectare of tropical peatland drained for plantations emits an average of 55 tons of carbon dioxide, equal to burning more than nearly 23,000 liters of gasoline.
One of the largest areas of tropical peatland in the world can be found in Indonesia, where devastating fires destroyed 2.6 million hectares of land in 2015. According to research conducted by the Center for International Forestry Research (CIFOR), it is estimated that 1.2 billion tons of emissions were released into the atmosphere.
One cause of the devastating fires was the canals that were built in the 1990s to drain natural peat swamps for agriculture. In the Kalimantan provinces in Indonesian Borneo, it’s estimated that more than 4,000 kilometers of these drainage canals had been dug.
DOWN TO THE WATER
The first step to rehabilitating these degraded peatlands is to restore the water table and rewet the surface area, providing a more fertile base for reforestation to begin.
“Degraded peatlands are subject to severe fires,” says CIFOR senior scientist Himlal Baral. “Restoration of degraded peatlands with rewetting by blocking canals is one of the most effective strategies to preventing fire and associated emissions reduction.”
Indonesia’s Peatland Restoration Agency (BRG), which is tasked with restoring 2 million hectares of degraded peatlands by 2020, has been working along with non-governmental organizations to block these canals. This will, in effect, help promote good peatland hydrology, which is key to restoring drained ecosystems.
A recent study conducted by the BRG and researchers from several universities looked at the effectiveness of canal blocking in rewetting tropical peatlands in Riau, a province on the island of Sumatra.
The team installed water loggers to monitor groundwater fluctuation around the canal block during a three-week period of a yearly dry season. They also measured water table levels from five dipwells located between 20 and 220 meters from the canal and collected rainwater data.
The results of this study show that the impact of canal blocking “could raise the water table in the peatland at a radius of about 170 meters from the canal” depending on the hydrotopography and land cover in the area.
The local community also reported that there have been no fires since they blocked the canals, and as an additional benefit, the sago plantation located near the canal has flourished due to proper irrigation.
Similar research in West Kalimantan compared blocked and unblocked canals. The scientists found that peatland in the blocked areas was able to retain water longer. “The water table can be maintained in the short term and it is expected to restore the hydrological function of peatland in the long term.”
BACK TO NATURE
These studies contribute to a much larger challenge: managing groundwater levels throughout a vast landscape. This can only be achieved through good forestry management practices, including ensuring vegetation is restored on degraded peatlands.
Research conducted over the past several years in Central Kalimantan shows that there are “very limited possibilities for natural regeneration.” The researchers say this is because once the natural canopy is lost, the area below becomes hot and dry, and nutrients in the soil are lost. They also note that without regulating vegetation, “both flooding and drought are also more pronounced.”
Planting the right species in the right places is key to successful peatland restoration. The BRG is focusing on local species as part of the re-vegetation program.
POWER TO THE PEOPLE
Restoring peatlands can not only prevent fires and the massive release of greenhouse gases but also help the livelihoods of communities through bioenergy. Biomass produced through the process of peatland restoration can be used to make bioenergy, and certain types of marketable bioenergy tree species can be grown to provide financial incentives to local communities to restore and sustainably manage their peatlands.
“Peatlands restoration, bioenergy and food production can be integrated on a landscape scale,” says Baral. However, he points out that “to achieve this, communities need to be involved. They cannot volunteer forever for nature and environmental conservation. They need some economic incentives to support their livelihoods.”
Earlier this year, scientists from CIFOR and the U.S. Forest Service urged countries to protect peatlands as part of their climate change strategies. In a special issue of the journal Springer, researchers compared tropical peatlands in Indonesia, the Congo Basin and the Peruvian Amazon.
The authors concluded that policies must recognize peatlands as unique and vulnerable carbon sink ecosystems, and protecting and restoring peatlands is vital not only in the fight against climate change but also in preserving biodiversity, increasing clean water, boosting the livelihoods of local communities and controlling both fires and floods.