Tropical Rainforest

Tropical rainforests are essential to the global ecosystem and human survival.

They form a world like no other and are incomparable in terms of their biological diversity. Tropical rainforests are a natural reservoir of genetic diversity which offers a rich source of therapeutic plants, high yield foods, and a myriad of other useful forest products. They are an important habitat for nomadic animals and continue as much as 50 percent of the species on Earth, as well as a number of diverse and unique cultures. Tropical rainforests play an elemental role in regulating global weather in addition to maintaining regular rainfall, while buffering against floods, droughts, and erosion. They store vast quantities of carbon, while producing a significant

The sheer range of numbers alone suggests the limited extent of our knowledge of these forests. For example, whereas temperate forests are often conquered by a half dozen tree species or fewer that make up 90 percent of the trees in the forest, a tropical rainforest may have more than 480 tree species in a single hectare (2.5 acres). A single bush in the Amazon may have more species of ants than the entire British Isles. This diversity of rainforests is not a chaotic event, but is the result of a series of unique circumstances.A tropical rainforest is typically divided into four main layers, each with different plants and animals modified for life in that particular area: the emergent, canopy, understory, and forest floor layers.

Emergent layer

The emergent layer contains a small number of very large trees called emergents, which grow above the general canopy, reaching heights of 4555 m, although on occasion a few species will grow to 7080 m tall. They need to be able to endure the hot temperatures and strong winds in some areas. Eagles, butterflies, bats, and certain monkeys inhabit this layer.

Canopy layer

The canopy layer contains the majority of the largest trees, typically

These mega rivers are fed by countless smaller tributaries, streams, and creeks. For example, the Amazon alone has some

1,100 tributaries, 17 of which are over 1,000 miles long. Although large tropical rivers are fairly uniform in appearance and water composition, their tributaries vary greatly. Many tropical rivers and streams have extreme high and low water levels that occur at different parts of the year.

In addition to rivers, rainforests have predictable, freestanding lakes and so called oxbow lakes, formed when a river changes course. These lakes are home to species adapted to the quiet, stagnant conditions. Tropical waters, whether they be giant rivers, streams, or oxbow lakes, are almost as rich in animal species as the rainforests that surround them. But they, too, are progressively more threatened by human activities, including pollution, siltation resulting from deforestation, hydroelectric projects, and overharvesting of resident