Peatlands
Peatlands are wetlands where waterlogged conditions slow decay and let partially decomposed plant material build into peat. They cover a small share of land but store vast amounts of carbon, shape water flows, support specialized species, and become major emission sources when drained or burned.
What peatlands are
Peatlands are wetland ecosystems defined by peat: layers of partly decomposed plant material preserved in saturated, low-oxygen soil. They include bogs, fens, mires, peat swamp forests, and other wet landscapes. What unites them is not a single look, but a process: plants grow, die, and accumulate faster than microbes can fully break them down.
How peat forms
Peat forms slowly when water keeps oxygen away from dead roots, mosses, sedges, leaves, and wood. In many northern peatlands, sphagnum moss helps hold water and acidify the surface. In tropical peatlands, flooded forests can build deep organic soils from woody vegetation. The result may take centuries or millennia to develop, which is why peat loss is hard to replace on human timescales.
Carbon storage
Because peat is built from plant material, it stores carbon that was once taken from the air by photosynthesis. Global estimates vary by definition and mapping method, but major conservation sources agree that peatlands store a disproportionately large share of the worldเน€เธยเนยเธเธขยs soil carbon compared with their land area. Keeping peat wet slows decomposition and helps keep that carbon underground.
Water and landscape functions
Healthy peatlands act like living water infrastructure. They can hold water, slow runoff, buffer floods, support stream flows during dry periods, and influence water quality. These services depend on local setting: a blanket bog, a boreal fen, and a tropical peat swamp forest do not behave identically. But in each case, the water table is central to the ecosystemเน€เธยเนยเธเธขยs function.
Biodiversity and archives
Peatlands support specialized plants, insects, birds, fish, amphibians, mammals, fungi, and microbes adapted to wet and often nutrient-poor conditions. They also preserve records. Pollen, plant remains, charcoal, and sometimes human artifacts can survive in peat, giving researchers evidence about past climates, vegetation, fire, and land use.
Damage and emissions
Drainage for farming, forestry, peat extraction, infrastructure, and development lowers the water table and exposes peat to oxygen. The stored organic matter then decomposes, releases carbon dioxide, and can subside or become vulnerable to severe fires. In some regions, drained peatlands have become a major source of greenhouse gases and smoke pollution despite occupying a small share of land.
Restoration
Peatland restoration usually starts with water. Blocking drainage channels, rewetting soils, reducing fire risk, and allowing peat-forming vegetation to recover can reduce emissions and restart ecosystem functions. Restoration is not instant: a rewetted peatland may take years to stabilize and far longer to rebuild deep peat. Protection of intact peatlands is therefore usually the cheapest and least risky option.
Why it matters
Peatlands connect climate policy, biodiversity conservation, water management, Indigenous and local livelihoods, agriculture, forestry, and public health. Their value is easy to miss because much of it sits below the surface. Once drained or burned, however, that hidden store becomes visible as carbon loss, land subsidence, haze, habitat decline, and higher restoration costs.