Peatlands in Asia that are being deforested to grow crops, are haemorrhaging carbon from deep within their peat soils, with potentially serious consequences for the environment.
Tropical peatlands form vast stores of organic carbon, tens of metres thick. The majority are in Indonesia, where the natural swamp forest are increasingly being destroyed to make way for agriculture – in particular oil palm for biofuels and food.
Dr Sam Moore, lead author of the study and former Open University PhD student, explained: “We measured carbon losses in channels draining intact and deforested peatlands, and found it is 50 per cent higher from deforested swamps, compared to intact swamps.
"Dissolved organic carbon released from intact swamps mainly comes from fresh plant material, but carbon from the deforested swamps is much older – centuries to millennia – and comes from deep within the peat column.”
Carbon lost from the drainage systems of deforested and drained peatlands is often not considered in ecosystem exchange carbon budgets, but the research team found it increased the estimated total carbon loss by 22 per cent.
Dr Vincent Gauci, Senior Lecturer in Earth Systems and Ecosystem Science at The Open University, and corresponding author, said: “Essentially, ancient carbon is being dissolved out of Asian peatlands as they are increasingly being turned over to agriculture to meet global demands for food and biofuels.
"This has led to a large increase in carbon loss from Southeast Asian rivers draining peatland ecosystems – up by 32 per cent over the last 20 years, which is more than half the entire annual carbon loss from all European peatlands.
"The destruction of the Asian peat swamps is a globally significant environmental disaster, but unlike deforestation of the Amazon, few people know that it is happening."
More information and related courses
- Deep instability of deforested tropical peatlands revealed by fluvial organic carbon fluxes
- Peatland forest destruction raises climate concern
- Open University media release
- S396 Ecosytems
- S288 Practical Science
- S216 Environmental Science
Image: Oil palm plantation. The cultivation of oil palms for food and biofuels is a significant cause of peatland deforestation. Image source: Thinkstock
