Peatlands

Peatlands are wetlands in which thick layers of partially decayed vegetation, known as peat, accumulate over long timescales. They form in waterlogged environments where oxygen is scarce, slowing decomposition and allowing plant material to build up faster than it decays. While often found in cool temperate and boreal regions, tropical peatlands occur in Southeast Asia, Africa, and South America as peat swamp forests. Peatlands cover roughly 3% of the world’s land surface and contain a large fraction of the planet’s soil carbon.

Two major types are bogs and fens. Bogs are ombrotrophic, receiving most of their water and nutrients from precipitation, which makes them acidic and nutrient-poor. Fens are minerotrophic, fed by groundwater or mineral-rich water, and typically support a higher nutrient status. In addition to these, tropical peat swamps and blanket peat landscapes occur in various climates. The hydrology of peatlands—especially a high water table near the surface—drives their distinctive chemistry and ecology.

Peatlands support specialized plant and animal communities. Sphagnum mosses are important in many northern bogs, contributing to acidity and peat preservation. The ecosystems provide services such as long-term carbon storage, water filtration, flood mitigation, and habitat for diverse flora and fauna.

Threats include drainage for agriculture or forestry, peat extraction, and fires, all of which can release stored carbon and degrade structure and function. Climate change can intensify drying, warming, and fire risk. Restoration efforts focus on rewetting drained areas, reestablishing hydrology, and promoting peat-forming vegetation to recover carbon storage and ecological integrity.