Sumatran lowland rain forests
The Sumatran lowland rain forests ecoregion covers the lowland forests running the length of the island of Sumatra in Indonesia. The region is one of exceptionally high biodiversity, similar to Borneo and New Guinea islands. Many endangered mammals species are present, and over 450 species of birds have been found in the region. In recent years, illegal logging and human encroachment have put great strain on this ecoregion.
Location and description
The ecoregion runs for 1,600 km down the northeast and southwest sides of the Barisan Mountains on the island of Sumatra. The ecoregion thus surrounds the higher elevation Sumatran montane rain forests ecoregion. The lowlands rainforest is at an average elevation of, and a maximum of. Also in this region are the islands of Simeulue, Nias, and Bangka Island off the east coast.Climate
This ecoregion has a tropical rainforest climate. This climate is characterized as hot, humid, and having at least 60 mm of precipitation every month. The lowland rain forests on the west side of the Barisan Mountains are wetter than those on the east side.Flora and fauna
The characteristics trees in the lowland rain forest are those of family Dipterocarpaceae . On Sumatra, 111 species of these trees have been recorded, six of which are endemic. These trees in the canopy can reach 90 meters in height. The dipterocarps in the understory are joined by smaller trees of the 'peacock flower' family. Other trees include torchwood trees, evergreens of the family Sapotaceae, member of the coffee family, members of the soursop family, laurels, and the nutmeg family. Trees of the mulberry family are also common, with over 100 species. Epiphytes are common. There is little ground vegetation, mostly saplings of canopy trees. The soils are commonly Podzols in the lowland rain forest.Mammals and birds are very diverse, with species similar to Borneo and the Malaysian Peninsula as all three landmasses were connected in the last ice age. Mammals of conservation interest include the endangered Asian elephant ', the endangered Lar gibbon ', the endangered Malayan tapir ', and the critically endangered Sumatran rhinoceros '. Over 450 species of birds have been recorded. Many endemic species are found in the biodiversity hotspot around Lake Toba, located in the caldera of a supervolcano.