The archipelago that connects Southeast Asia with Australia contains all of the major kinds of tropical rainforest, including extensive heath forests and huge areas of peat swamp forest in Sumatra, Malaysia and Borneo.
While the rainforests of the Africa and the Americas lie on large continents, there is no place within the Far Eastern rainforests that is more than a couple of hundred miles from the sea.
The rainforests of the Far East are also much more mountainous than the African and American Rainforests
Sunda and Sahul Shelves
The Malay Peninsula and the western islands of Sumatra, Java and Borneo lie on the Sunda continental shelf, an extension of Asia.
In the east, New Guinea and its associated islands lie on a second shelf, the Sahul, which extends from Australia.
The biogeographical boundary that separates these two regions is known as the Wallace Line.
Both of these shelves have been dry during the low sea levels of the Ice Ages of the last two million years.
The rainforest animals of Sundaland are Asian; those of the Sahul shelf are Asian. There are also important, though less extreme, differences in plant life.
An important difference between forests of the west and east is the abundance of trees belonging to the dipterocarp family in Sundaland.
Dipterocarps occur in all kinds of lowland and in lower montane rainforest. They are most diverse in dry land rainforest, such as in parts of Borneo and the Philippines, where they dominate the upper canopy.
In the eastern part of the region, dipterocarp species are less common.
The southern outlying rainforests of Queensland, Australia, and the eastern outliers of the Solomon and New Hebrides archipelagos are no more abundant in species and no taller than some temperate forests.
On New Guinea, the main bastion of the eastern rainforest block, instability of the land due to landslides on the steep, immature mountain slopes, frequent earthquakes and volcanic activity has a profound effect on the forests.
Malaysia, Borneo and Sumatra in the western bastion are much less prone to catastrophic disturbance.
Products of the Rainforest
World crops that come from this region include teak, bananas, citrus fruits and sugarcane.
Southeast Asian dipterocarp forests supply a large number of tropical hardwoods for international trade.
The Asian rainforests have long provided many other valuable commodities including rattans and climbing palms for furniture, diverse tree fruits, including the durian, rambutan and mangosteen, and various gums and resins.