North Selangor Swamp Forest
Location:
3°25'-3°42'N, 101°05'-101°27'E; north of Sungei Selangor and northeast of Kuala Selangor, Selangor State.
Area:
74,823 ha.
Altitude:
Sea level.
Biogeographical Province:
4.7.1.
Wetland type:
11 & 21.
Description of site:
A low-lying, flat, peat-swamp forest bordered on the eastern side by somewhat hillier land with oil palm and rubber plantations. In the northern part, the forest is crossed by Sungei Tengi. Much of the forest has already been extensively logged, but some virgin tracts remain. Freshwater swamp forest formerly occurred in the Sungei Tinggi area (Wyatt-Smith, 1963), but this has now disappeared. The swamp forests lie in the Kuala Selangor hydrological region, which is defined in general terms as having loose clayey and sandy deposits with the lowest category of potential water run-off (Goh, 1974). The soils are defined by Wong (1970) as being of the Inland Swamp Association. Peat depths of over 5.5m have been recorded in the Kuala Selangor area. In the deep peat areas, there is usually a metre or so of peaty water between the true fibrous peat and the alluvial clay below. Virtually the whole area has been classified in soil suitability class 4 (more than one serious limitation to crop growth and suitable for a very restricted range of agricultural and forest crops). At the edges of the area, the soil is classified in class 2 (moderate limitation to crop growth and suitable for a not too wide range of agricultural and forest crops), class 3 (one serious limitation to crop growth and suitable for a restricted range of agricultural and forest crops), and class 5 (at least one serious limitation to crop growth and best retained under forestry use).
Climatic conditions:
Humid tropical climate with an average annual rainfall of less than 2,000 mm. The wettest months are April and October-December, the driest, January-February and July. The climate is generally equatorial, with rain from both the northeast and southwest monsoons, although the latter is mitigated by the mountains of Sumatra.
Principal vegetation:
Mixed swamp forest, according to the classification of Anderson (1961). Wyatt-Smith (1959) describes the west coast peat swamp forests as exceedingly rich and especially so where the peat is deep. The generalized forest structure consists of a fairly level upper tree storey which reaches a height of about 30 metres. The density of forest varies, but is less than that of lowland evergreen rain forest, and frequently has an open non-continuous canopy. Emergents are normally absent. The understorey consists of a fairly continuous canopy extending from about six to 18 metres above peat level. Beneath this is a shrub layer and relatively poor ground flora. The dominant larger trees are usually Calophyllum scriblitifolium, Gonystylus bancanus, Koompassia malaccensis, Myristica lowiana, Shorea rugosa and Tetramerista glabra. There are extensive oil palm and rubber plantations in adjacent areas, extensive rice-growing areas to the west, and lowland dipterocarp forest and marine alluvial swamp forest to the northeast.
Land tenure:
The southern part is State Land (Government of Selangor); Sungei Dusun Game Reserve is state owned.
Conservation measures taken:
The North Selangor Swamp Forest is in the process of being gazetted into two large Forest Reserves comprising a total of 74,823 ha (the Sungei Karang and Raja Musa Forest Reserves). About 400 ha of forest along the northeastern edge of the site overlap with the Sungei Dusun Game Reserve (Strict Nature Reserve). The Game Reserve was established in 1964 and covers 4,280 ha.
Conservation measures proposed:
The Sungei Karang and Raja Musa Forest Reserves would be suitable for classification as "Flood Control Forest" under the National Forestry Act 1984, in view of the vital role that peat swamps play in flood mitigation in northern coastal areas. This same function makes it essential that peat swamp forests never be cleared without a thorough environmental impact assessment of likely hydrological effects (SPSSM, in prep).
The presence of remnant virgin tracts provides an excellent opportunity for Jabatan Perhutanan, perhaps with assistance from the Forest Research Institute of Malaysia, to plan a system of Virgin Jungle Reserves and Research Forest plots. These could include selected examples of forest where the peat extends to different depths and where different harvesting regimes (or no harvesting) have prevailed in the past (SPSSM, in prep). At present there are no Virgin Jungle Reserves or Research Forests in northern Selangor.
The site has particular value in being large enough to hold areas that might be conserved as representative natural communities. Virgin Jungle Reserves set within buffering production forest may play a role here, but wildlife protection would not be adequate without an extension of Sungei Dusun Game Reserve (SPSSM, in prep).
Future decisions on land use in the area should take a holistic planning approach, taking into account agricultural, forestry, conservation and hydrological considerations, amongst others.
Land use:
Commercial timber production; cultivation of oil palms, rubber and rice in surrounding areas. The western and eastern edges of the area are gazetted as Malay Reserves. An area of about 400 ha around 3°34'N, lOl°9'E has been alienated for agricultural purposes (EPU, 1980).
Possible Changes in Land use:
Conversion for agricultural uses and mining.
Disturbances and threats:
The area is seriously threatened by over-exploitation and reclamation for agriculture. Much of the forest has already been extensively logged. In the southeastern corner, an area of about 3,600 ha is covered by extant mining leases or mining certificates; this whole area is currently used for mining or has mining potential. The northern half of the area is mapped as potentially productive forest (EPU, 1980). Disruption of the water table will affect water supply to the nearby Sekincan rice paddies. There is some hunting with shotguns, probably for fruit bats at night.
Economic and social values:
The site plays a critical role in the hydrology of the area, reducing local flooding and probably acting as an important water supply to the Sekincan rice paddies. The swamp forest also has significant forestry value, mainly in terms of timber production and forestry research. The area is of outstanding value for scientific research on peat swamp ecology, hydrology and forestry.
Fauna:
The forest supports a considerable variety of bird species, including raptors such as Haliaeetus leucogaster, Falco peregrinus, Microhierax fringillarius, and the hornbills Buceros rhinoceros and Anthracoceros malayanus convexus. Fruit bats (Pteropodidae) are common, and the highly endangered Sumatran Rhinoceros Dicerorhinus sumatrensis is still present on the eastern side. The adjacent Sungei Dusun Game Reserve supports healthy populations of Cervus unicolor, Muntiacus muntjak, Sus scrofa, Tragulus javanicus, primates, civets and rodents. Other mammals present in the reserve in smaller numbers include Panthera tigris, P. pardus, Tapirus indicus, Helarcios malayanus and D. surnatrensis.
Special floral values:
The swamp forest contains many commercially valuable tree species. With virgin tracts still remaining, the site is a good example of a west coast peat swamp forest and is of great value as a gene pool.
Research and facilities:
The Department of Wildlife and National Parks has conducted a study of the ecology of Dicerorhinus surnatrensis in Sungei Dusun Game Reserve. Few studies have been carried out on the vegetation, although detailed investigations have been made in the nearby Hutan Melintang Forest Reserve and in the south Selangor peat swamp forests.
References:
Anderson (1961); EPU (1980); Goh (1974); IUCN (in prep); Marsh & Wilson (1981); Ministry of Forestry (1986); SPSSM (in prep); Whitmore (1984); Wong (1970 & 1974); Wyatt-Smith (1959).
Criteria for Inclusion:
1b, 2a, 2b.
Source:
Department of Wildlife and National Parks (Peninsular Malaysia), SPSSM and Asian Wetland Bureau.