Nepedia
Back to Discover
Advanced Reader
🌍

Peatland

earth science Maturity 9-11 Next article →

Peatlands are unique wetland ecosystems defined by thick layers of organic matter known as peat.

Avaste soo põhjaosa vaated %283%29
Avaste soo põhjaosa vaated %283%29

This peat forms when dead plant material fails to decompose completely. In most environments, bacteria and fungi break down dead vegetation quickly. However, peatlands remain saturated with water, creating a state called anoxia. Anoxia means there is a lack of oxygen in the soil. This lack of oxygen prevents microbes from fully breaking down the organic matter. Consequently, the dead plants pile up over thousands of years to form deep soil layers.

The formation of a peatland follows a specific biological and physical sequence. It often begins through paludification, where mineral soil forests become waterlogged. It can also happen through terrestrialisation, which is the process of a lake filling with organic matter. Once the peat begins to accumulate, it can actually raise the ground surface. This accumulation can eventually lift the land above the surrounding landscape. A peatland that is actively growing new peat is called a mire.

Ruwenzori Upper Bigo Bog
Ruwenzori Upper Bigo Bog

If the peatland is drained or dried out, it may still contain peat, but it is no longer considered a mire.

Ecologists classify mires into several distinct types based on their water sources. A bog is an ombrotrophic mire, meaning it receives all its water from precipitation like rain or snow. Because rain is low in minerals, bogs are always acidic and nutrient-poor. In contrast, a fen is a minerotrophic mire. Fens receive water from groundwater or surrounding mineral soil. This allows fens to be neutral or alkaline and can make them nutrient-rich. Some peatlands also include swamps, which are characterized by a forest canopy or dense vegetation like papyrus.

PEATMAP
PEATMAP

Peatlands are critical to the Earth's climate because they are the largest natural carbon store on land. Although they cover only about 3% of the Earth's surface, they store over 600 gigatons of carbon. This is more carbon than is stored in all other vegetation types, including all the world's forests combined.

PEATMAP
PEATMAP

They also sequester approximately 0.37 gigatons of carbon dioxide every year through photosynthesis. Beyond carbon storage, peatlands provide ecosystem services like purifying water and reducing flood risks. They act as a natural cooling mechanism for the atmosphere by keeping greenhouse gases locked in the soil.

These ecosystems are distributed globally, but their characteristics change with the climate. The largest concentration of peatlands, making up about 64% of the total, is in the Northern Hemisphere. These are found in temperate, boreal, and subarctic zones. In polar regions, mires are often shallow due to slow accumulation rates. In the tropics, peatlands are rarer but can be massive. For example, Indonesia contains about 24 million hectares of peatland. The Central Congo Basin also holds the world's largest tropical mire, covering 145,500 square kilometers.

Burned Peatland in Indonesia
Burned Peatland in Indonesia

Human activity and climate change pose significant threats to these environments. Many peatlands are drained for agriculture, such as the conversion of land for palm oil plantations.

Kunak-District Sabah Oil-palm-plantation-01
Kunak-District Sabah Oil-palm-plantation-01

Others are harvested for commercial peat use. When peatlands are drained, the water table falls and oxygen enters the soil. This allows aerobic microbes to accelerate decomposition, which releases stored carbon dioxide back into the atmosphere. Furthermore, drying peatlands are highly susceptible to fires.

Unseasonal peat fire in Russia (Copernicus)
Unseasonal peat fire in Russia (Copernicus)

These fires release massive amounts of greenhouse gases, further driving climate change.

Scientists also use peatlands as a window into the Earth's history. Because peat accumulates in layers, it traps pollen, metals, and macrofossils. Researchers can use carbon-14 dating to determine the exact age of these layers. This allows them to reconstruct past climates and study historical pollution levels. However, if these lands are destroyed by dredging, this irreplaceable scientific record is lost forever. Understanding the complex chemistry of peat, such as its high cation-exchange capacity, remains vital for protecting these global carbon sinks.

Research in to response of northern peatlands to increases in temperature and atmospheric carbon dioxide (9358)
Research in to response of northern peatlands to increases in temperature and atmospheric carbon dioxide (9358)
631 words

Where will your curiosity go next?

Keep exploring at your chosen reading level.

🖼️ Images & Media (12)
File:ARG-2016-Aerial-Tierra del Fuego (Ushuaia)–Valle Carbajal 01.jpg
ARG-2016-Aerial-Tierra del Fuego...
File:Avaste soo põhjaosa vaated %283%29.JPG
Avaste soo põhjaosa vaated %283%29.JPG
File:Ruwenzori Upper Bigo Bog.jpg
Ruwenzori Upper Bigo Bog.jpg
File:PEATMAP.jpg
PEATMAP.jpg
Carbon Cycle in Peatlands.pdf
File:Research in to response of northern peatlands to increases in temperature and atmospheric carbon dioxide (9358).jpg
Research in to response of northern...
File:Peat cuttings near Unasary - geograph.org.uk - 176303.jpg
Peat cuttings near Unasary -...
File:Borneo fires and smoke, 2002.jpg
Borneo fires and smoke, 2002.jpg
File:Burned Peatland in Indonesia.jpg
Burned Peatland in Indonesia.jpg
File:EE-Lahemaa-Bagno Viru.jpg
EE-Lahemaa-Bagno Viru.jpg
File:Kunak-District Sabah Oil-palm-plantation-01.jpg
Kunak-District Sabah Oil-palm-plantation-01.jpg
File:Unseasonal peat fire in Russia (Copernicus).jpg
Unseasonal peat fire in Russia (Copernicus).jpg
More to explore

✨ What else?

Related topics you might enjoy

🔬 Go deeper

More advanced topics to explore

🪜 Step back

Simpler topics to build understanding

What is Nepedia?

A free, ad-free encyclopedia for children. Every article is written at five reading levels, so the same page works for a five-year-old and a fifteen-year-old — use the level switcher above to see this one change. No account needed to read.