This picture shows the location of a peat dome in the flood plain in between two lowland rivers. A substantial part of the peat dome is located above river water surface. These forms of peatlands are called bogs, they are oligotrophic (poor in nutrients) and rain water fed. The peat lies like a gigantic drop a water on the lowland plain, held together by the dead organic material and protected by a blanket of living forest that maintains a humid micro-climate and prevents direct solar impact.
Nepenthes grows in soils with N deficiencies. It compensates this by capturing insects in its cup-shaped leaves. Many indigenous peat swamp forest plants and trees can survive long-inundation. They can form floating islands, such as the Pandanus, or have aerial roots or pneumatophores, that help them to breath.
Drainage - aeration of the peat soil – aerobic decomposition of peat (carbon content of 60kg/m3) – sustained release of CO2 and subsidence of peat dome – flooding downstream Loss of carbon sink capacity, at least 40Mt/yr due to present loss of peatswamp forests
Melling’s study is often used to claim that peat swamp forests would emit more CO2 than palm oil plantations. The study did, however, not measure the ecosystem carbon balance but only the soil emissions without distinguishing between CO2 emissions from peat oxidation and CO2 emissions from root respiration. It is logical that the latter will significantly impact on results. If peat swamp forest would indeed lead to a net higher CO2 emission, peat could never have been formed. The proof is in the peat.
Palm oil plantations are rapidly expanding in Malaysia and Indonesia due to increasing global demands for vegetable oil. Part of this is caused by the expected opportunities in the biofuel market.
Current national legislation does not protect carbon rich ecosystems (forests, peatlands).
Many tropical peatlands are being reclaimed and drained for palm oil; annual expansion 150,000 – 200,000 ha per year in SE Asia
Whether in intact peatswamp forests of in logged areas, additional emissions caused by the plantations are significant, adding tens of tons of carbon dioxide per hectare per year.
Emissions from drained peatland areas continue for decades or even centuries (depending on peat depth) until the entire stock is gone.
Several studies are conducted on the impact of drainage of peatlands on greenhouse gas emissions. While average emission totals of the irregular and fluctuating peatland fires occurrences are under discussion, there is widespread consensus on the emissions from peat decomposition due to drainage.