akar.earthPeatland: Definition
What is peatland? How tropical peat stores carbon, why drained peat burns and emits, how peat carbon is measured, and Indonesia's peat rules and projects.
Peatland is land with a layer of peat, a soil made of partly decomposed plant material that has built up over thousands of years under waterlogged conditions. Tropical peatlands, often covered by peat swamp forest, store very large amounts of carbon, mostly in the peat itself rather than in the trees.
Why it matters
Peat stays stable only while it is wet. Draining it for plantations, agriculture or logging canals lets it decompose and subside, releasing CO2 for decades. Dry peat also burns, sometimes for weeks underground, producing huge emissions and regional haze. Protecting and rewetting peat therefore avoids some of the highest per-hectare emissions in the land sector.
How peat carbon is measured
- Depth mapping: probes at many points to map peat thickness.
- Carbon density: bulk density and carbon content from core samples, applied by depth.
- Emissions: water table depth drives emission factors in the IPCC Wetlands Supplement.
- Fire: burned area and burn depth mapping.
- Methane: rewetting can raise methane, which must be counted.
Peat projects usually combine REDD+ on peat swamp forest with WRC rewetting. See our peatland REDD+ guide and the WRC entry.
Indonesia angle
Indonesia has some of the world’s largest tropical peat areas, concentrated in Sumatra (notably Riau, Jambi and South Sumatra), Kalimantan and Papua. Large peat fires in El Niño years, especially 2015, drove national reforms: peat protection regulations, a moratorium on new peat licences and a national restoration agency. Canal blocking and rewetting are core restoration tools. An Indonesian peatland project’s credit price nearly doubled after a one-band rating upgrade from ‘A’ to ‘AA’ in February 2025. See peat restoration rules.
Common mistakes
- Treating peat like mineral soil and sampling only the top 30 cm.
- Ignoring subsidence and fire in the baseline.
- Rewetting without accounting for methane.
Related terms
See WRC, soil organic carbon and REDD+, or explore the blue carbon hub.
Frequently asked questions
Why do drained peatlands emit carbon?
Draining lowers the water table, letting oxygen reach the peat. Microbes then decompose it, releasing CO2, and dry peat becomes highly flammable.
How is peat carbon measured?
By measuring peat depth at many points with probes, plus bulk density and carbon content from samples. Emissions are estimated from water table depth, subsidence and fire mapping.