The
Borneo peat swamp forests is a
tropical moist forestTropical and subtropical moist broadleaf forests , also known as tropical moist forests, are a tropical and subtropical forest biome....
ecoregion on the island of
BorneoBorneo is the third largest island in the world and is located at the centre of Maritime Southeast Asia. Administratively, this island is divided among Indonesia , Malaysia and Brunei . Indonesians refer to the island as Kalimantan...
, which is divided between
BruneiBrunei , officially the State of Brunei Darussalam or the Nation of Brunei, the Abode of Peace , is a country located on the north coast of the island of Borneo, in Southeast Asia...
,
IndonesiaThe Republic of Indonesia is a country in Southeast Asia and Oceania. Indonesia comprises 17,508 islands. With an estimated population of around 237 million people, it is the world's fourth most populous country, with the world's largest population of Muslims.Indonesia is a republic, with an...
and
MalaysiaMalaysia is a country in Southeast Asia that consists of thirteen states and three Federal Territories, with a total landmass of . The capital city is Kuala Lumpur, while Putrajaya is the seat of the federal government. The population stands at over 28 million inhabitants...
.
Peat swamp forestPeat swamp forests are tropical moist forests where waterlogged soils prevent dead leaves and wood from fully decomposing, which over time creates thick layer of acidic peat...
s occur where waterlogged soils prevent dead leaves and wood from fully decomposing, which over time creates thick layer of acidic
peatPeat is an accumulation of partially decayed vegetation matter. Peat forms in wetlandbogs, moors, muskegs, pocosins, mires, and peat swamp forests...
. Peat swamp forests occur in coastal lowlands, behind the brackish or salt-water
mangrove forestsMangroves are trees and shrubs that grow in saline coastal habitats in the tropics and subtropics – mainly between latitudes N and S. The saline conditions tolerated by various species range from brackish water, through pure seawater , to water of over twice the salinity of ocean seawater,...
that lie near the coast, and bounded by the Borneo lowland rain forests on better-drained soils.
Over the past decade, the government of
IndonesiaThe Republic of Indonesia is a country in Southeast Asia and Oceania. Indonesia comprises 17,508 islands. With an estimated population of around 237 million people, it is the world's fourth most populous country, with the world's largest population of Muslims.Indonesia is a republic, with an...
has drained over 1 million hectares of the Borneo peat swamp forests for conversion to agricultural land under the
Mega Rice ProjectThe Mega Rice Project was initiated in 1996 in the southern sections of Kalimantan, the Indonesian section of Borneo. The goal was to turn one million hectares of unproductive and sparsely populated peat swamp forest into rice paddies in an effort to allieviate Indonesia's growing food shortage....
. The dry years of 1997-8 and 2002-3 (see El Niño) saw huge fires in the peat swamp forests. A study for the
European Space Agency|owner = |headquarters = Paris|spaceport = Guiana Space Centre|image = ESA LOGO.svg|size = 240px|acronym = ESA|established = 1975|administrator = Jean-Jacques Dordain...
found that the peat swamp forests are a significant carbon sink for the planet, and that the fires of 1997-8 may have released up to 2.5 billion tonnes, and the 2002-3 fires between 200 million to 1 billion tonnes, of carbon into the atmosphere.
Indonesia is currently the world's third largest carbon emitter (when deforestation and land use changes are included), to a large extent due to the destruction of its ancient peat swamp forests (Pearce 2007).
About 62% of the world’s tropical peat lands occur in the Indo-Malayan region (80% in Indonesia, 11% in Malaysia, 6% in Papua New Guinea, with small pockets and remnants in Brunei, Viet Nam, the Philippines and Thailand: Rieley et al. 1996; Page et al. 2006). They are unusual ecosystems, with trees up to 70 m high - vastly different from the peat lands of the north temperate and boreal zones which are dominated by Sphagnum mosses, grasses, sedges and shrubs. The spongy, unstable, waterlogged, anaerobic beds of peat can be up to 20 m deep with low pH (pH 2.9 – 4) and low nutrients, and the forest floor is seasonally flooded (Yule 2008). The water is stained dark brown by the tannins that leach from the fallen leaves and peat – hence the name ‘blackwater swamps’. During the dry season, the peat remains waterlogged and pools remain among the trees. Despite the extreme conditions the forests are highly diverse with as many as 927 species of flowering plants and ferns recorded from the peat swamp forests of Borneo (Anderson 1963). A biodiversity study in the Pekan peat swamp forest in Peninsular Malaysia report 260 plant species (Latiff 2005). Although most of the tree families recorded in lowland dipterocarp forests (including Dipterocarpaceae) also occur in peat swamp forests, many species are only found here. Many trees have buttresses and stilt roots for support in the unstable substrate, and pneumatophores and hoop roots and knee roots to facilitate gas exchange. The trees have thick, root mats in the upper 50 cm of the peat to enable oxygen and nutrient uptake.
The lowland peat swamps of the region are mostly geologically recent, (< 5000 years old), low lying coastal formations above marine muds and sands (Rieley et al. 1992; Page et al. 2006), but some of the peat forests of Central Kalimantan (Indonesian Borneo) are up to 11,000 years old and occur at higher elevations over riverine sediments.
One reason for the low nutrient conditions is that streams and rivers do not enter these forests (if they did, nutrient rich freshwater swamps would result), they only flow out of them, so the only input of nutrients is from rainfall, marine aerosols and dust. In order to cope with the lack of nutrients, the plants invest heavily in defences against herbivory such as chemical (toxic secondary compounds) and physical defences (tough leathery leaves, spines and thorns). It is these defences that prevent the leaves from decaying and so they build up as peat. Although the cellular contents quickly leach out of the leaves when they fall, the physical structure is resistant to both bacterial and fungal decomposition and so remains intact, slowly breaking down to form peat (Yule and Gomez 2008). This is in stark contrast to the lowland dipterocarp forests where leaf decomposition is extremely rapid, resulting in very fast nutrient cycling on the forest floor. If non-endemic leaf species are placed in the peat swamp forests, they break down quite quickly, but even after one year submerged in the swamp, endemic species remain virtually unchanged (Yule and Gomez 2008). The only nutrients available for the trees are thus the ones that leach from the leaves when they fall, and these nutrients are rapidly absorbed by the thick root mat. It was previously assumed that the low pH and anaerobic conditions of the tropical peat swamps meant that bacteria and fungi could not survive, but recent studies have shown diverse and abundant communities (albeit not nearly as diverse as dry land tropical rainforests, or freshwater swamps) (Voglmayr and Yule 2006; Jackson, Liew and Yule 2008).
See also
- Peninsular Malaysian peat swamp forests
The Peninsular Malaysian peat swamp forests are a tropical moist forest ecoregion of the Malay Peninsula, which includes portions of Malaysia and southern Thailand.-Setting:...
- 1997 Southeast Asian haze
The 1997 Southeast Asian haze was a large-scale air quality disaster which occurred during the second half of 1997, its after-effects causing widespread atmospheric visibility and health problems within Southeast Asia...
- Sabangau River
- Tropical peat
Areas of tropical peat are found mostly in South East Asia although are also found in Africa, Central and South America and elsewhere around the Pacific Ocean. Tropical peatlands are significant carbon sinks and store large amounts of carbon and their destruction can significantly impact on the...
References
Anderson JAR (1963) The flora of the peat swamp forests of Sarawak and Brunei. Including a catalogue of all recorded species of flowering plants, ferns and fern allies. Garden’s Bull. Singapore 29: 131-228
Latiff A (2005) An overview of the significant findings of the biodiversity expedition to the peat swamp forest of Sungai Bebar, Pahang. In: Latiff A, Hamzah KA, Ahmad N, Said MNM, Toh AN, Gill SK (eds) Biodiversity Expedition Sungai Bebar, Pekan, Pahang, Summary Findings. Peat Swamp Forest Project, UNDP/GEF Funded, in collaboration with the Pahang Forestry Department and University Kebangsaan Malaysia
Jackson, C.R., Liew, K.C. and Yule, C.M (2008) Structural and functional changes with depth in microbial communities in tropical peat swamp forest sediments. Microbial Ecology DOI: 10.1007/s00248-008-9409-4
Page SE, Rieley JO, Wüst R (2006) Lowland tropical peatlands of Southeast Asia In: Martini IP, Martínez Cortizas A, Chesworth W (eds) Peatlands: Evolution and Records of Environmental and Climate Changes. Elsevier BV pp 145-172
Pearce F (2007) Bog barons: Indonesia's carbon catastrophe. New Scientist 1 December 2007.
Rieley JO, Ahmad-Shah AA Brady MA (1996) The extent and nature of tropical peat swamps. In: Maltby E, Immirzi CP, Safford RJ (eds) Tropical lowland peatlands of Southeast Asia, proceedings of a workshop on integrated planning and management of tropical lowland peatlands held at Cisarua, Indonesia, 3-8 July 1992. IUCN, Gland, Switzerland
Rieley JO, Sieffermann RG, Page SE (1992) The origin, development, present status and importance of the lowland peat swamp forests of Borneo. Suo 43: 241-244.
Yule CM (2008) Loss of biodiversity and ecosystem functioning in Indo-Malayan peat swamp forests. Biodiversity and Conservation DOI: 10.1007/s10531-008-9510-5
Yule, C.M. and Gomez, L. (2008). Leaf litter decomposition in a tropical peat swamp forest in Peninsular Malaysia. Wetlands Ecology and Management. DOI: 10.1007/s11273-008-9103-9
Voglmayr, H. and Yule, C.M. (2006)
Polyancora globosa gen. et sp. nov., an aeroaquatic fungus from Malaysian peat swamp forests. Mycological Research. 110:1242-1252.
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