The Sumatran Tropical Pine Forests are not as species-rich as the surrounding montane forests but do contain similar species as well as those adapted to the vegetation.
Location and General Description
This ecoregion represents the tropical pine forests in northern Sumatra near Lake Toba and along the Barisan Mountain Range. These forests occur within the montane zone of Sumatra. About 150 million years ago Borneo, Sumatra, and western Sulawesi split off from Gondwanaland and drifted north. Around 70 million years ago India slammed into the Asian landmass, forming the Himalayas, and an associated thrust formed Sumatra's Barisan Mountains, which run the length of Sumatra.
Based on the Köppen climate zone system, Sumatra falls in the tropical wet climate zone. The montane forests of the Barisan Range receive more rainfall on their western slopes than their eastern slopes, which are in a rainshadow. However, most of Sumatra experiences less than three consecutive months of dry weather (less than 100 millimeters rainfall/month), and rainfall in the montane rain forests averages more than 2,500 millimeters/year. However, the pines exploit the drier areas in the mountain range, mostly on the eastern slopes.
It is in the drier areas that forests are dominated by the Sumatran pine (Pinus merkusii). This species originally was an early pioneer of disturbed land (such as landslides). However, repeated burning of the montane forests by natural and human-made disturbance has caused thick pine forests with a pauce ground layer to become established.
The flora and fauna of the pine forests are not as diverse as those of the surrounding montane or lowland rain forests. There are no endemic or near-endemic mammals in this [[ecoregion]. Only 3 to 4 percent of the bird species found in the surrounding rain forests were also found in pine forests. A large majority of the bird species found in these forests are common to disturbed or secondary forests. Twelve near-endemic bird species are attributed to this ecoregion (Table 1).
|Table 1. Endemic and Near-Endemic Bird Species.|
|Phasianidae||Bronze-tailed peacock-pheasant||Polyplectron chalcurum|
|Campephagidae||Sunda minivet||Pericrocotus miniatus|
|Irenidae||Blue-masked leafbird||Chloropsis venusta|
|Turdidae||Shiny whistling-thrush||Myiophonus melanurus|
|Muscicapidae||Rufous-vented niltava||Niltava sumatrana|
|Muscicapidae||Sunda robin||Cinclidium diana|
|Pycnonotidae||Cream-striped bulbul||Pycnonotus leucogrammicus|
|Pycnonotidae||Spot-necked bulbul||Pycnonotus tympanistrigus|
|Pycnonotidae||Sunda bulbul||Hypsipetes virescens|
|Zosteropidae||Black-capped white-eye||Zosterops atricapillus|
|Timaliidae||Sunda laughingthrush||Garrulax palliatus|
|Timaliidae||Rusty-breasted wren-babbler||Napothera rufipectus|
|An asterisk signifies that the species' range is limited to this ecoregion.|
The pine forests are found in montane areas, and large portions of the ecoregion are within two national parks, Kerinci Seblat and Lingga Isaq (Table 2). This ecoregion burns frequently from anthropogenic and natural causes.
|Table 2. WCMC (1997) Protected Areas That Overlap with the Ecoregion.|
|Protected Area||Area(km2)||IUCN Category|
|Ecoregion numbers of protected areas that overlap with additional ecoregions are listed in brackets.|
Types and Severity of Threats
The pine forests are under much less threat than the lowlands and surrounding montane forests. More than a third of the ecoregion is in protected areas, and the ecoregion lacks high-value dipterocarp tree species. Therefore, these forests are under less threat from logging than the surrounding landscape.
Justification of Ecoregion Delineation
The Pinus merkusii-dominated conifer forests along the Gunung Leuser Range are shown and identified as a distinct ecoregion, the Sumatran Tropical Pine Forests. These forests are the only stands of Pinus found south of the equator. Another tropical pine forest, the Luzon Tropical Pine Forests ecoregion, also occurs in the Philippines, and it developed under similar conditions. MacKinnon's biounit 21 largely corresponds to Udvardy's Sumatra biogeographic province. However, Udvardy did not include the Nicobar Islands. There are eight ecoregions that overlap Udvardy's Sumatra biogeographic province: Sumatran Lowland Rain Forests, Sumatran Montane Rain Forests, Mentawai Islands Rain Forests, Sumatran Peat Swamp Forests, Sumatran Freshwater Swamp Forests, Sundaland Heath Forests, Sumatran Tropical Pine Forests, and Sunda Shelf Mangroves.
Additional Information on this Ecoregion
- For a shorter summary of this entry, see the WWF WildWorld profile of this ecoregion.
- To see the species that live in this ecoregion, including images and threat levels, see the WWF Wildfinder description of this ecoregion.
- World Wildlife Fund Homepage
- Whitten, A. J., M. Mustafa, and G. S. Henderson. 1987. The Ecology of Sulawesi. Yogyakarta, Indonesia: Gadjah Mada University Press. pp xxi + 779, 64 pls.
- National Geographic Society. 1999. National Geographic atlas of the world: seventh edition. Washington, DC: National Geographic Society.
- Whitmore, T. 1984. A vegetation map of Malesia at scale 1:5 million. Journal of Biogeography 11: 461-471.
Disclaimer: This article is taken wholly from, or contains information that was originally published by, the World Wildlife Fund. Topic editors and authors for the Encyclopedia of Earth may have edited its content or added new information. The use of information from the World Wildlife Fund should not be construed as support for or endorsement by that organization for any new information added by EoE personnel, or for any editing of the original content.