Peninsular Malaysian peat swamp forests

The Peninsular Malaysian Peat Swamp Forests, though not as diverse in species as the surrounding lowland rain forests, are home to many of Malaysia's endangered species. Asian elephants, Sumatran rhinoceros, tigers, clouded leopards, and Malayan tapir all inhabit these rapidly shrinking forests.

Location and General Description This ecoregion represents the disjunct peat swamp forests in peninsular Malaysia and southern Thailand. Based on the Köppen climate zone system, this ecoregion falls in the tropical wet climate zone.

The peat swamp forests of peninsular Malaysia have edaphic and vegetative characteristics similar to those in Sumatra and Borneo. The soil is infertile and primarily organic matter. Peat deposits found behind mangroves are recent in origin. They are formed when rivers drain into the inland edge of a mangrove and trap the sediments within their tangle of roots. As these areas build up, they flood less frequently. The peat deposits can extend between 50 centimeters (cm) and 20 meters (m). Because peat swamps are not drained by flooding, they are acidic (pH usually is less than 4) and nutrient deficient. Compared with other lowland rain forest ecoregions, peat forests are not as species-rich and have fewer endemic species.

The ecoregion plays a significant role in acting as a sink for water from surrounding habitat. The edge of this forest is characterized by strangler figs (Ficus spp.), whose fruits provide an important source of food for many of the mammal, bird, and fish species. The vegetation is not dominated by a single dipterocarp (such as Shorea albida in Borneo), but Shorea macrophylla (bintangor) is an important timber tree. Pandan and the sealingwax palm (Cyrtostachys lakka) give the understory a characteristic appearance.

Biodiversity FeaturesThe freshwater swamp forest, fauna is much more diverse than the fauna of peat swamp forests, being more similar to lowland rain forests. Many of the characteristic species of lowland rain forests are also found here. There are five large endangered mammals found in this ecoregion: the tiger (Panthera tigris), Asian elephant (Elephas maximus), Sumatran rhinoceros (Dicerorhinus sumatrensis), Malayan tapir (Tapirus indicus), and clouded leopard (Pardofelis nebulosa). The avifauna is not as diverse as that of the Malaysian lowland rain forests and does not include any endemic species, but the grey-headed fish eagle Ichthyophaga ichthyaetus and brown fish owl Ketupa zeylonensis are thought to be specialists in this habitat. The importance of peat swamp forest for freshwater biodiversity, and in particular small fish diversity (e.g., species of Betta), has recently been demonstrated by surveys by Wetlands International.

Current StatusMore than half of this small ecoregion has been cleared or degraded. Most of the remaining habitat is found along the eastern coast of peninsular Malaysia. The ecoregion does not receive any formal protection. These forests did not escape the pervasive forest fires that raged through Malaysia and Indonesia in 1997-1998.

Types and Severity of Threats These forests are threatened by logging, tin mining, and clearance for agriculture including rice, rubber, coconut, and oil palm. Coastal swamp forests continue to be cleared for development, and drainage of neighboring land can draw down the water table. Until recently water extraction has been an unlicensed activity; attention has been drawn to this problem by water use for eel farming in Pahang. The combination of disturbance, lowering of the water table, and surrounding activities has increased risks of fire; significant areas near the Pahang coast were burnt in 1997-1998.

Justification of Ecoregion DelineationThe Peninsular Malaysian Rain Forests ecoregion represents the large extent of the lowland broadleaf rain forests extending south of the Kangar-Pattani line to Singapore. The tropical montane evergreen moist forests above 1,000 m were placed in the Peninsular Malaysian Montane Rain Forests. We also extracted the large areas of peat swamp forests along the coast of peninsular Malaysia into the Peninsular Malaysian Peat Swamp Forests. Thus, we created three ecoregions within MacKinnon's Malay Peninsular subunit (07a). Udvardy combined all of Borneo into the Borneo biogeographic province