Slow decomposition of dead plant material
Indonesia and Malaysia are home to the world’s largest areas of tropical peat swamps. The peat swamps were formed over thousands of years, by dead organic matter falling in layers on soil soaked – or saturated – by fresh water. The water saturation makes the soil low in oxygen, which causes the decomposition of dead plant parts to be extremely slow. That’s why dead leaves, grass, moss and rotting tree trunks pile up on top of each other to form peat. The dead plant parts contain large amounts of carbon – which is stored in the peat for thousands of years, instead of being released into the atmosphere as carbon dioxide.
Tropical peat swamps are slowly decomposing soils saturated with water. The water turns dark and is called blackwater - due to its high content of humic acids from the soil.
Photo: Christian-Hinz-CC-BY-SA
Peat consists of dead plant material, which decomposes slowly, due to the soil's low oxygen content.
Photo: Jonas-Barandun-CC-BY-SA
A river running through a tropical peat swamp on Borneo.
Photo: Ruanda-Agung-Sugardiman-CC-BY
The dark, acidic water in a tropical peat swamt creates a unique habitat.
Photo: S.J.D, Parosphromenus Project
The free water in tropical peat swamps can be very shallow, but the water saturated peat below can be as deep as 20 meters.
Photo: Mankdhay-rahman-CC-BY-SA
As acidic as vinegar
The water in tropical peat swamps is dark and acidic. This is due to the acidic substances, known as humic acids, in the peat. In some peat swamps, it can be as acidic as vinegar, and that’s completely natural. The free water can be shallow, perhaps only a few centimetres deep. But the water-saturated peat below can be as deep as 20 metres. Tropical peat swamps are a unique habitat. That’s why many species of fish in swamps are exclusive to their particular area.
This satellite picture shows smoke from the forest fires on Borneo 2019. The wildfires got very extensive, because of the dry and highly flammable peatlands.
Fire-fighters working hard trying to extinguish the wildfires in Indonesia 2015. The photo shows a ditch, which has been part in draining the surrounding peat swamp.
Photo: NASAs-Earth-Observatory-CC-BY
Tropical peat burned in Indonesia during the great wildfires of 2019.
Photo: DenY-Krisbiyantoro-CC-BY-SA
When the peat burns
It takes thousands of years to form a tropical peat swamp, but destroying one doesn’t take long. Many companies grow palm trees for palm oil in Southeast Asia, digging ditches through the peat to get land for cultivation. The ditches drain the soil of water, and the peat dries out. After draining, the forest growing on the peatland is burnt down. When the peat meets oxygen from the air, decomposition begins. It happens quickly – and carbon that has been trapped in the soil is released into the atmosphere. When the forest is burned during dry periods, the peat can easily catch fire – and burning peat is difficult to extinguish. The fire can penetrate deep into the ground, smoulder for several years and sometimes flare up. The fires emit so much carbon dioxide that Indonesia is now ranked as the world’s third largest emitter of greenhouse gases.
A tropical peat swamp in Indonesia, destroyed to set up palm oil cultivation.
Photo: Aidenvironment-Wakx-CC-BY-SA
When tropical peat swamps are destroyed, so is the habitat for many species such as the endangered liquorice gourami.
Photo: S.J.D, Parosphromenus project
Sweden and other European countries also destroy their peatlands, to make way for forestry and agriculture. The peat is also used as a fuel, burned to produce heat and electricity. The destruction of European peatlands also has a negative impact on the climate.
Photo: Lars-Falkdalen-Lindahl-CC-BY-SA
Peat extraction in Ireland.
Photo: Pamela-Norrington-CC-BY-SA
Important habitat
Tropical swamps are home to forests, which are an important habitat for many large endangered species, such as Sumatran tigers and orangutans. Of the unique fish species that live in swamps, no one knows how many have already been wiped out by deforestation. A single scoop with an excavator can, in the worst case, wipe out an entire species. Important research is now underway in Indonesia and Malaysia to find as many species as possible and save them before it’s too late.
A dam blocking a canal in a peat swamp forest in Indonesia. This dam will help maintain water levels in the forest.
Photo: Josh-EsteyAusAID-CC-BY
The endangered orangutans, among many other species, depend highly of the tropical peat swamps in Indonesia and Malaysia.
Photo: diego_cue-CC-BY-SA
Liqourice gouramis are a group of fish living their lives in the dark and acidic waters of the tropical peat swamps. All liqourice gourami species are highly endangered, due to destruction of the tropical peat swamps.
Photo: Martin-Fischer-CC-BY-SA
What can I do about it?
Palm oil is found in food, sweets, cakes, make-up and many other products. Look for palm oil-free products in the store!
Join WWF and other organisations campaigning in Malaysia and Indonesia, or get politically involved in environmental issues.
Write to the head offices of stores trading in products containing palm oil and to EU politicians, regardless of which EU countries they come from, who are working with environmental issues and trade.