We asked for questions about the amazing carbon-storage capabilities of peatlands, and how these ecosystems keep the planet breathing. Readers sent us more than a thousand. Here are some answers.
Credit Illustrations by Eden Weingart
What exactly is a peatland?
Line Rochefort: You cannot really define a peatland without defining peat. Peat is an organic soil largely consisting of dead organic matter and visible plant remains. Peat accumulates, and is not deposited by water or ice or wind.
Rod Chimmer: Peatlands are very diverse, and found across the planet. Their many names can become very confusing to ordinary people and scientists alike, which is why “peatlands” is a better term to use most of the time.
Different kinds of peatlands are often classified by their source of water. For example, bogs are peatlands that are supported by precipitation only, while fens have groundwater in them. Bogs and fens often occur together, and most bogs are created from fens.
Miriam Jones: You have to look below the surface to know whether a wetland is a peatland. In the northern boreal hemisphere, peatlands can be composed of sphagnum mosses and sedges. Temperate and tropical peatlands are often swamps, which are forested wetlands. Some coastal marshes — which are dominated by grasses, sedges and rushes — and mangrove forests also accumulate peat.
Peatlands can also evolve with time. For example, many boreal peatlands began as fens, and once peat accumulation reached a certain point transitioned to bogs. Not all wetlands accumulate peat, so not all wetlands are peatlands, but all peatlands are wetlands.
Besides mosquitoes, what lives in a peatland?
Jorge Hoyos-Santillan: Peatlands are biodiversity hot spots in some regions of the planet. Patagonian peatlands hold more than 200 species of insects and a wide variety of amphibians. They are also home to foxes, guanacos, pumas, and migratory birds such as flamingos. On the other hand, lowland tropical peatlands — peatlands found in and around rainforests — are incredibly biodiverse both in flora and fauna. For example, the peatlands located in Panama are among the most biodiverse ecosystems in America. Hundreds of bird species migrate through these peatlands every year. In addition, they are home to mammals (e.g., jaguar, tapir, ocelot), reptiles, amphibians (e.g., poisonous frogs) and insects. Flora in these ecosystems is so biodiverse that most of it has not yet been discovered.
Scott J. Davidson: Up close, peatlands are a patchwork quilt of different types of vegetation, including certain species of tree, sphagnum moss, lichens, sedges, dwarf shrubs such as blueberry and cranberry and some of the famous carnivorous plants, like the pitcher plant and the sundew.
Miriam Jones: Carnivorous plants are most common in bogs that are fed only by precipitation, and are therefore more nutrient poor. Various pitcher plant species are found in nutrient-poor peatlands across the world, and Venus flytraps are most commonly found in North and South Carolina. A variety of sundew species are found from the Arctic to the tropics.
How do peatlands capture carbon, and why is it so important to the planet?
Edward Struzik: Peatlands represent just 3 percent of the world’s terrestrial surface, but store twice as much carbon as all the world’s forests combined. Canada’s Hudson Bay Lowlands, the largest intact peatland in the world, stores as much as five times more carbon than the equivalent area in the Amazon rainforest.
Miriam Jones: Plants growing at the peat’s surface take up carbon dioxide from the atmosphere. In most other ecosystems, when plants die, they decompose, returning that carbon to the atmosphere. In peatlands, however, the water at or close to the surface limits oxygen. Without oxygen, decomposition is slow. Much of this plant matter only partially decomposes, then accumulates in layers, turning into peat. Peat sequesters carbon because the decomposition is slower than the accumulation, and over time peat can accumulate to be several meters thick.
Gusti Anshari: Major factors that directly affect the degradation of tropical peats are land use and peat fires. The Intergovernmental Panel on Climate Change forecasts that the tropical peat ecosystem could become a large contributor to atmospheric carbon dioxide.
Jones: Destroying the world’s peatlands could double the amount of carbon in the atmosphere. Peatlands have accumulated this carbon since the last ice age, about 20,000 years ago, but mostly in the last 11,500 years or so. Globally, damaged peatlands are net carbon sources — that is, they release carbon into the atmosphere — through disturbances like drainage or fires, or the drying of the peat surface and thawing of permafrost due to climate change. Some peatlands, however, especially in the northern high latitudes, remain net carbon sinks.
Struzik: When frozen peatlands in the Arctic and sub-Arctic begin to thaw, they reach a point where they can no longer absorb and store carbon, and start emitting it instead. This is already happening. Wildfires and climate change are accelerating this thawing. In 2007, the largest recorded tundra fire to occur in the Arctic, which burned 401 square miles, released as much carbon into the atmosphere as the tundra has stored in the previous 50 years.
Why can’t we create, build or plant new peatlands?
Edward Struzik: Bog gardens can be created, so long as there is lots of water, shade and seeds. The Wildlife Trusts can help you get started if you want to create a bog, and the conditions in your area are suitable. But be careful of what you wish for in a garden. Mosses such as sphagnum are the master builders of peat. They are, for want of a better term, serial killers. They snuff out vascular plants. Tulips and turnips, beware!
Steve Frolking: Peatlands store carbon as peat slowly accumulates, so constructing peatlands may be a long-term approach to addressing carbon in the atmosphere, but it cannot be a short-term solution. Peatlands can lose their stored carbon much more quickly than they can store it, particularly if disturbed by fire, drainage, or a harvest, for example.
Scott J. Davidson: Creating peatlands from scratch is a difficult task, but there have been some projects that looked at reclaiming previous peatland landscapes and restoring the conditions needed for peat accumulation and carbon sequestration. One such project that I have been involved with looked at building a fen on a landscape previously disturbed by oil and gas activities in the Athabasca Oil Sands Region in Alberta, Canada.
Sophie Wilkinson: The Athabasca Oil Sands Region project attempted to create a landscape that would feed water into a “new” peatland, built from stockpiled peat. In this way, rather than merely restoring peatland vegetation on the ground surface, the project engineered the environment to function in a sustainable, long-term manner to support the development of peatland species, as well as ecosystem services such as water filtration and carbon uptake. Despite some issues surrounding salt intrusion, this project has shown promise, and provided many vital lessons for future peatland reclamation.
How do we preserve or restore peatlands?
Rod Chimner: In general, the less disturbed the peatland is, the faster it can usually be restored. For instance, peatlands can be restored with little cost in a few weeks, using simple techniques and volunteers, if the peatland is lightly disturbed. It can take decades and millions of dollars to restore more seriously damaged ones, as is happening with projects in Indonesia and the Everglades.
Not all aspects of a peatland will recover at the same rate. Peatland hydrology can recover within weeks after ditch blocking or other rewetting techniques, whereas plants may take a few years or decades to recover, depending on how degraded the vegetation was and the type involved. Recovery of biodiversity can also take a long time as plants, animals, insects and microbes need to make their way back into the site.
Edward Struzik: Several conservation organizations in North America have taken up the challenge of protecting peatlands. The Nature Conservancy is leading many restoration efforts, in places such as the Great Dismal Swamp in southeastern Virginia and northeastern North Carolina. The Wildlands League, a chapter of the Canadian Parks and Wilderness Society, is working with Audubon and indigenous organizations to protect the Hudson Bay Lowlands, the largest intact peatland in the world, from mining developments. Ducks Unlimited is working with landowners and indigenous people all over North America to protect peatlands. There are also a growing number of small local groups dedicated to this effort. Most of them, however, don’t have the resources to do what needs to be done.
Sophie Wilkinson: The United Nations Environment Program is working hard to help connect different groups, from nations to communities, to protect peatlands. In fact, the Global Peatlands Initiative has been formed to promote conservation and best practices in management and restoration, in particular of tropical peatlands.
How much peat is used for gardening?
Miriam Jones: Peat that is harvested today can be hundreds or thousands of years old. It can be harvested much faster than it accumulates, so one problem with a horticultural peat harvest is that a nonrenewable resource is being depleted.
Jorge Hoyos-Santillan: Nowadays, most of the imports and exports of peat are related to agriculture, horticulture and flower packing. Unfortunately, to extract peat it is necessary to remove the vegetation cover and it usually requires draining the peatlands to ease the extraction. By altering the hydrology and removing the vegetation, the overall carbon balance in the peatland usually shifts from carbon sink to carbon source. In terms of climate change mitigation, peat extraction is a net contribution to global warming. Worldwide peat extraction is a massive economic activity; Canada and the European Union are the largest exporters.
Sophie Wilkinson: Peatland conservation and its enormous potential to help mitigate climate change is gaining traction across many countries. Last year the U.K. laid out a plan to ban the use of sphagnum peat in commercial compost. This will reduce the need for peat harvesting. However, given that there are few affordable or sustainable alternatives to peat compost, there is a worry that compost producers will import peat to fill the demand, leading to a negative effect on peatland conditions globally, even if those in the U.K. are better conserved. This exemplifies the need to embed peatland conservation into policy on an international scale, to ensure that real progress is made and sustained.
Edward Struzik: There are alternatives to peat, like blends of coconut and wood fiber, but they tend to be expensive, not as widely available in North America as in Europe and not as effective as natural peat. But in recent years, the quality of these products has greatly improved, so it’s worth giving them a try, including the new compost made from household waste.
Exactly where are all the peatlands in the world?
Steve Frolking: Although they occupy only about 3 percent of the earth’s land surface, peatlands are widespread, occurring from the tropics to the arctic.
Edward Struzik: Peatlands are highly diverse and vary widely under permanently waterlogged, predominantly acidic conditions all over the world. They are most dominant in the temperate and boreal regions of the Northern Hemisphere. But the recent discovery of a massive tropical peatland in Congo, several thousand smaller ones in the southern Rockies and the Andes, still functional remnants in the Mojave and other deserts and untold numbers yet to be sufficiently identified in the Arctic speak to the fact that mapping these unique ecosystems is a work in progress. They may well represent more than just that 3 percent.
Jorge Hoyos-Santillan: As awareness grows about the importance of peatlands as a fundamental component in a country’s climate strategy, national estimations of peatlands’ overall extent have improved. In Chile, prior to the COP25 summit, the uncertainty regarding the extent of peatlands was high. Estimates ran from 2.3 to 6.1 million hectares. Since Chile included peatlands in its national climate strategy, and committed to developing a national peatland inventory, research has been conducted to address this knowledge gap, and many wetlands are now being recognized as peatlands. Another example is Panama. Until now, the only peat deposits in the country were identified in the Caribbean. But this year another peat deposit was discovered on the Pacific shore, in the Darien Province. The global area of peatlands is expected to increase as these ecosystems become widely included in climate strategies throughout the world.
Meet the Bog Squad
The Bog Squad is a group of scientists, researchers, academics, writers and educators Headway convened to help shape its peatland coverage, including providing answers to the following questions.
This FAQ was a collaborative effort among the Bog Squad and the Headway team. We will continue to add to this page as more questions are asked. If you have more queries, you can ask us here.
The Bog Squad members that answered these questions include:
Gusti Anshari, Ph.D., is a professor of tropical peatlands at Tanjungpura University in Indonesia. Anshari is collaboratively working on peatland conservation, restoration, and sustainability.
Rod Chimner, Ph.D., is a professor of wetland ecology at Michigan Technological University. Chimney’s research program focuses on peatland ecology and restoration in temperate, mountain, and tropical peatlands. He also teaches a senior level wetland ecology and management course and a graduate level restoration ecology course.
Scott J. Davidson, Ph.D., is a lecturer in ecosystem resilience at the University of Plymouth in the United Kingdom. Davidson’s research is focused on the response, recovery and resilience of peatland ecosystems to both climate change and disturbance regimes. He is also co-founder of PEAT: Peatland ECR Action Team, which connects early career peatland scientists to develop a diverse, inclusive, and supportive research community.
Steve Frolking, Ph.D., is a research professor at the Earth Systems Research Center at the University of New Hampshire’s Institute for the Study of Earth, Oceans, and Space. Frolking develops and uses simulation models to study the carbon balance of peatlands over tens to thousands of years, and to assess the climate trade-offs of simultaneous carbon sequestration into peat and methane emissions.
Jorge Hoyos-Santillan, Ph.D., is a researcher at the University of Magallanes Environmental Biogeochemistry Lab in Chile, an adjunct researcher at the Center for Climate and Resilience Research and an associate professor at the University of Nottingham in the United Kingdom. Hoyos-Santillan’s research interests focus on the study of biogeochemical cycles.
Miriam Jones, Ph.D., is a research geologist at the Florence Bascom Geoscience Center for the U.S. Geological Survey. Jones is a paleoecologist and paleoclimatologist, viewing peatlands and other wetlands as archives of past vegetation and climate change.
Line Rochefort, Ph.D., is the Director of the Peatland Ecology Research Group at Université Laval in Canada. Rochefort specializes in peatland ecology and restoration.
Edward Struzik is the author of “Swamplands: Tundra Beavers, Quaking Bogs and the Improbable World of Peat,” and a fellow at Queen’s Institute for Energy and Environmental Policy, Queen’s University in Canada. Struzik is a book and magazine writer, university researcher and lecturer, and an occasional rapporteur who spends much of his time exploring varied and often unappreciated landscapes beyond our towns and cities.
Sophie Wilkinson, Ph.D., is a Natural Sciences and Engineering Research Council of Canada postdoctoral fellow at the University of Toronto. Wilkinson works at the interface of science and management, characterizing peatland-wildfire behavior and impacts and developing management techniques to reduce peatland fire severity.
Many more “peatheads” have participated in conversations with Headway about its peatlands project. If you’d like to join the Bog Squad or have any questions, let us know below.
Read at The New York Times.