Sunday, August 14, 2011

Basic Knowledge of Tropical Rainforest

A tropical rainforest is a place roughly within 28 degrees north or south of the equator. They are found in Asia, Australia, Central America, Mexico and on many of the Pacific Islands. The rainforest is humid. Tall, broad-leaved evergreen trees are the dominant plants, forming a leafy canopy over the forest floor. Taller trees, called emergents, may rise above the canopy. The upper portion of the canopy often supports a rich flora of epiphytes, including orchids, bromeliads, mosses, and lichens, who live attached to the branches of trees. The undergrowth or understory in a rainforest is often restricted by the lack of sunlight at ground level, and generally consists of shade-tolerant shrubs, herbs, ferns, small trees, and large woody vines which climb into the trees to capture sunlight. The relatively sparse under story vegetation makes it possible for people and other animals to walk through the forest. In deciduous and semi-deciduous forests, or forests where the canopy is disturbed for some reason, the ground beneath is soon colonized by a dense tangled growth of vines, shrubs and small trees called jungle.

The rainforest is divided into five different layers and they are the emergent layer, canopy, understorey layer, shrub layer and forest floor.

The emergent layer contains a small number of very large trees which grow above the canopy layer, reaching heights of 45-55 m, although on occasion a few species will grow up to 40 m or 50 m tall. They need to be able to withstand the hot temperatures and strong winds. Eagles, butterflies, bats and certain monkeys inhabit this layer.

The canopy is the primary layer of the forest and forms a roof over the two remaining layers. Most canopy trees have smooth, oval leaves that come to a point. It's a maze of leaves and branches. Many animals live in this area since food is abundant. Those animals include: snakes, toucans and tree frogs.

Little sunshine reaches the understorey layer, so the plants have to grow larger leaves to obtain sufficient sunlight. The plants in this area seldom grow to 3 m (10 feet). Many animals live here including jaguars, red-eyed tree frogs and leopards. There is a large concentration of insects here.

The shrub layer and forest floor are very dark. Few plants grow in this area, as a result. Since hardly any sun reaches the forest floor things begin to decay quickly. A leaf that might take one year to decompose in a regular climate will disappear in 6 weeks. Giant Anteaters live in this layer.

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