Welcome to the site about the Indonesian Tropical Rainforest!
Please take your time to look over all the interesting facts about it.
- The tropical rainforest is earth's most complex biome in terms of both structure and species diversity.
- It only occurs under optimal growing conditions: abundant precipitation and year round warmth.Sunlight is the major limiting factor.
- Climate is mean monthly temperatures are above 64¡ F; precipitation is often in excess of 100 inches a year. There is usaully a brief season of reduced precipitation. In monsoonal areas, there is a real dry season, but that is more than compensated for with abundant precipitation for the rest of the year.
- Vegetation: A vertical stratification of three layers of trees is apparent. These layers have been labeled A, B, and C
- Since only 1% of the light that hits the top of the canopy enters the bottom part of the forest there are many different types of plants on the bottom: Epiphytes, Lianas, Climbers, Stranglers, and Heterotrophs.
- Common characteristics of tropical trees. Tropical species frequently possess one or more of the following attributes not seen in trees of higher latitudes.
Buttresses: many species have broad, woody flanges at the base of the trunk. Originally believed to help support the tree, now it is believed that the buttresses channel stem flow and its dissolved nutrients to the roots. Large leaves are common among trees of the C layer. Young individuals of trees destined for the B and A layers may also have large trees. When the reach the canopy new leaves will be smaller. The large leaf surface helps intercept light in the sun-dappled lower strata of the forest. Drip tips facilitate drainage of precipitation off the leaf to promote transpiration. They occur in the lower layers and among the saplings of species of the emergent layer (A layer).
- Other characteristics that distinguish tropical species of trees from those of temperate forests include: Exceptionally thin bark, often only 1-2 mm thick. Usually very smooth, although sometimes armed with spines or thorns. Cauliflory, the development of flowers (and hence fruits) directly from the trunk, rather than at the tips of branches. Large fleshy fruits attract birds, mammals, and even fish as dispersal agents.
- Soil: Oxisols, infertile, deeply weathered and severely leached, have developed on the ancient Gondwanan shields. Rapid bacterial decay prevents the
accumulation of humus. The concentration of iron and aluminum oxides by the laterization pro cess gives the oxisols a bright red color and sometimes produces
minable deposits (e.g., bauxite). On younger substrates, especially of volcanic origin, tropical soils may be quite fertile.
- Subclimaxes: Distinct communities (varzea) develop on floodplains. Jungles may line rivers where sunlight penetrates all layers of the forest. Where forests have long been cleared and laterites have developed to cause season waterlogging of the sub strate, tropical grasslands and palm savannas occur.
- Fauna: Animal life is highly diverse. Common characteristics found among mammals and birds (and reptiles and amphibians, too) include adaptations to an arboreal life (for example, the prehensile tails of New World monkeys), bright colors and sharp patterns, loud vocalizations, and diets heavy on fruits.
- Distribution of biome: The tropical rainforest is found between 10 ¡ N and 10 ¡ S latitude at elevations below 3,000 feet. There are three major, disjunct formations:
Neotropical (Amazonia into Central America)
African (Zaire Basin with an outlier in West Africa; also eastern Madagascar)
Indo- Malaysian (west coast of India, Assam, southeast Asia, New Guinea and Queensland, Australia. The species composition and even genera and families are distinct in each. They also differ from species of temperate forests. Species diversity is highest in the extensive neotropical forest; second in the highly fragmented Indo-Malaysian formation; and lowest in Africa. Where 5 to a maximum of 30 species of tree share dominance in the Temperate Broadleaf Deciduous Forest, there may be 40 to 100 different species in one hectare of tropical rainforest. Tropical species of both plants and animals often hav e very restricted distribution areas.
Footnotes - Fauna: Animal life is highly diverse. Common characteristics found among mammals and birds (and reptiles and amphibians, too) include adaptations to an arboreal life (for example, the prehensile tails of New World monkeys), bright colors and sharp patterns, loud vocalizations, and diets heavy on fruits.