Piles of un-decomposed, waterlogged plant material known as peatlands cover about 3 percent of Earth’s land and freshwater surface area. But scientists and conservationists are just beginning to fully understand the role of peatlands in the environment.
“Peatlands are relatively little studied compared to other ecosystems, partly because of the difficulty of access due to their high water table and often soft surface,” said Faizal Parish, director of the Malaysia-based Global Environment Centre.
The organization maintains an online database that serves as a clearing house of information for the global peatland conservation community. Peatland studies, Parish added, also suffer from a lack of awareness about their importance and function.
But Harri Vasander, a professor of peatland forestry at the University of Helsinki in Finland, said peatland studies are on the increase.
“Peatlands and peat itself are really important and fascinating,” he said.
“During the last 15 years we have started to understand better their roles in regulating hydrology and the climate.”
What is Peat?
According to Larry Smith, an associate professor of geography at the University of California, Los Angeles, peat is simply layer upon layer of undecomposed plant material.
“Peat accumulates anywhere in the environment where you have plants growing and forming biomass faster than their remains can be decomposed,” he said.
Smith likens a peat bog to a coral reef: Living mosses, sedges, shrubs, and trees lie on a deep bed of un-decomposed, soggy plant matter like living corals on top of a bed of hardened calcium deposits from dead corals. Peatlands are found on all continents except for Antarctica and from sea level to high altitudes. Northern latitudes are particularly well suited for peat, because decomposition rates are slow in cold, wet environments, Smith said.
Smith’s research recently showed that the world’s most extensive peatlands are located in the west Siberian lowlands, covering 232,000 square miles (600,000 square kilometers). He is now trying to tease out how these peatlands help govern the mix of greenhouse gases in the atmosphere.
According to Parish, peatlands around the world store 25 to 30 percent of all the carbon in terrestrial ecosystems and regulate the flow of water.
“Peatlands store significant amounts of fresh water and release it to maintain groundwater and surface-water supplies. Peatlands also absorb water during heavy rainfall and release it slowly to rivers, playing a role in flood control,” he said.
In Malaysia and other tropical regions, Parish said peatlands are home to more than 1,500 plant species and 150 fish species. In more northern latitudes the variety of species is less, but the peatlands serve as an important refuge during periods of climate instability.
Peat Uses
Scientists estimate about 80 percent of the world’s peatlands are relatively intact, primarily in North America and Siberia. However, they are under increasing pressure from human activities, especially in populated regions of Europe and the tropics.
“They have been wastelands and people have wanted to change them to productive lands,” Vasander said. For hundreds of years peatlands have been drained to make room for agriculture. In the last 30 years, Parish said, the pace of peatland destruction has accelerated, primarily to meet the needs of the timber and pulp and paper industries.
For example, in northern Finland, 14 million acres (5.7 million hectares) of peatlands have been drained for forestry to increase tree growth on peat, Parish said.
“In the tropics the naturally forested peatlands have been badly degraded by extensive drainage as part of operations to extract the timber,” he added.
Peatlands are also harvested for use by gardeners as potting soil, and in some parts of the world peat is mined to burn as a fuel.
“This is a very intensive way of using peatlands, but the percentage worldwide is quite small,” Vasander said. “There are, however, countries like Finland and Ireland, which use a lot of peat for energy. In Finland, the share of peat is 6 to 7 percent of the country’s total energy consumption.”
Smith said he and his colleagues used Russian maps drawn up for potential peat mining operations to calculate the extent of peatlands in the western Siberian lowlands. The Russians never mined the Siberian peat; they went for the oil and natural gas beneath it.
Peat Conservation
According to Smith, the rush to extract the oil and natural gas beneath the vast peatlands of Siberia is spurring a fledgling conservation movement.
“There are concerns among Russians scientists about their pristine ecology being damaged. But [the peatlands] are huge, and nothing is going to stop the economy of the area,” he said.
At the global scale, however, the peatland-conservation movement is picking up steam, Parish said. For example, an action plan for peatland conservation is being developed under the Convention on Wetlands, signed in Ramsar, Iran, in 1971. The convention is an intergovernmental treaty which provides the framework for national action and international cooperation for the conservation and wise use of wetlands and their resources.
“In those areas where [peatlands] have become rare, people start to understand [peatlands’] different functions and values,” Vasander said. “But still, in many places they are considered to be wastelands, and the conversion continues.”