Russia — The fires in Russia this summer made headlines mostly because of the smoke, haze and human health effects in large metropolitan areas like Moscow. But there is a disturbing story behind this story. Most fires are burning peat that is tens of thousands of years old. These slow burning, smoldering fires dont provide the dramatic photo ops that forest fires do.
But peat fires spew enormous amounts of carbon dioxide and other greenhouse gases into the atmosphere and may be a significant contributor to global warming.
Peat, which covers an estimated 2 percent of the planets land surface, has served as a fuel for humans over millennia (even today peat provides a significant source of energy in nations such as Ireland and Finland). Peat fires are a natural part of the worlds carbon cycle; they have always been with us and they always will be.
The problem is that human mismanagement of peat bogs has created more and larger peat fires. And Russia, which has experienced a summer of blistering heat, drought, failed crops as well as fires, is a perfect example. Russian land-use decisions have exacerbated the risk of peat fires. Nearly a century ago, swamps were drained to extract peat to provide electricity to Moscow. Never reflooded, the remaining dry peat was kindling for the fires.
However, ecosystems with large peat deposits (the largest are in Russia, Canada, Indonesia, and the United States) dont typically experience fires that cause extensive burning of the peat itself. Most fires in peat systems burn over the surface of typically water-saturated peat deposits, only burning the dry vegetation litter above the peat. In most systems, peats are typically found to be saturated, cold and wet, and as a result, they dont readily catch fire or burn. Most peat fires occur in altered landscapes where ditches or tiles have been dug into the peats to dewater these substrates. This is usually done so that the peat itself can be harvested as fuel (Russia), crops can be grown in the substrates (Indonesia), or for manufacturing soil amendments for agricultural or horticultural uses (United States and Canada).
The mere act of dewatering peat also allows peats to begin deteriorating and to release GHGs, much like when a compost pile of leaves and garden waste rots down. This process of deterioration, even in the absence of wildfires, is well known to many Midwestern U.S. farmers who crop peat soils. In the late 1800s and early 1900s many of these farmlands were installed with deep ditches and clay tiles to dewater these peats. Dewatering was necessary to use the peat substrates for growing crops. In most such settings the decomposition of the peats has resulted in the subsidence of the landscape surfaces, and as the surface of the substrates approaches the shallow water table, farmers have to deepen ditches and add a new, deeper layer of drainage tiles. Even without fires, this deterioration process has been estimated to have released many hundreds of millions of tons of GHGs into the atmosphere.
Peat substrates are found in locations where the annual plant matter produced on the landscapes accumulates, rather then decomposing. This often occurs in wetland ecosystems or systems that remain saturated through most of the year. As plant matter accumulates, depending on the degree of degradation, different types of peat are produced. Some peats are called fibric because by looking at the intact plant fibers you can identify the original types or species of plants. The sphagnum moss, for instance, found in garden centers and used in the floriculture industries, is a typical fibric peat. When the fibers decompose further, and a black, gluey constituency remains, they are called muck peats.
All peat substrates are an accumulation and concentration of carbon-rich substrates. Often, peat deposits contain 50 percent to 80 percent carbon, so that when they combust, they liberate huge quantities of GHGs: carbon dioxide, but also nitrous oxide and methane (vastly more potent greenhouse gases than CO2). Thus, peat substrates, next to all other soils in general, are one of the largest concentrations of stored carbon on Earth and serve as crucial carbon sinks.
The danger of peat fires is much closer to home than Russia or Indonesia. For most of the summer of 2008 a huge peat fire burned in coastal North Carolina, releasing an estimated 22 million tons of carbon into the atmosphere and creating dense haze and smoke that covered areas as far away as Raleigh and Durham. This occurred in North Carolinas Pocosin wetlands, which were ditched and drained starting in the 1950s for agricultural purposes.
Guillermo Rein, an assistant professor at the University of Edinburgh in Scotland and an expert on peat fires, told environmental journalist Andrew Revkin recently that such fires have received very little research attention . The lack of knowledge on smoldering fires is a barrier to tackle the problem, noting that a much larger international effort is required from society and scientists.
Its in this spirit that my firm, Applied Ecological Services Inc., and its partner organization, The Earth Partners, have joined forces with a group of federal, university, and nonprofit organizations to study GHG emissions from dewatered peats in North Carolinas Pocosin wetlands.
It is clear, however, that the best assurance to stopping the fires in the first place can only be done by resaturating the peats. The peat mining industries, including the sphagnum peats mined for the floriculture industry, represent an increasing risk of fire. This industry is now developing plans to reduce and protect their harvesting areas against the risk and threat of fires.
Still, many previously disturbed peat lands are not being restored or actively protected from this fire risk. They pose a serious threat to the health of humans and the planet, and, as Professor Rein points out, there remains much work to done.