Tropical Peat Swamp Forests of Southeast Asia

Abstract

Tropical peatlands of Southeast Asia occupy an estimated area of 248,000 km² (56% of the global resource). They store ^∼50 gigatonnes (Gt = t ×10⁹) of carbon. Lowland tropical peat consists of organic matter from the partially decomposed remains of trees that accumulates to a thickness of 10 m or more. It is characterized by low ash and nutrient contents and high acidity. Under natural conditions, the water table is close to or at the peat surface for much of the year. The natural vegetation is forest that forms a continuum of different types from the edge to the centre of the peat dome. Many of the trees show adaptations to the waterlogged environment, for example, buttress and stilt roots and pneumatophores. Peat swamp forests have high biodiversity and are important habitats for many species of mammals, birds, fish and amphibians, some of which are endangered. In addition, they provide an array of other important ecosystem services. Land use changes are causing rapid loss and degradation of peat swamp forests driven by timber extraction and plantation establishment. Peat oxidation and fire have contributed substantially to global greenhouse gas emissions. Prospects for peat swamp forests are not promising, although initiatives such as the UN REDD+ programme may ensure that some remaining forests are safeguarded.