The tropical rainforests are found primarily near the equator in areas such as the Pacific Islands, Africa, Asia, and South America. They are the oldest living ecosystems of the earth. The Amazonian rainforest in South America is the largest. Rainforests are characterized by a stable, warm, wet climate. The temperature ranges between 68 degrees F (20 degrees C) and 93 degrees F (34 degrees C) with the average yearly rainfall being at least 160 and up to 400 inches, according to The Nature Conservancy. For this reason, tropical rainforests lack seasons, remain green and are very humid (about 80%).
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Rainforest canopy as seen from the air.
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The tallest trees (which form the emergent layer) attain heights of
about 200 feet (61m). The tops (or crowns) of other shorter trees form a leaf cover habitat called the upper canopy. A range of even shorter trees form one or two levels called the lower canopies or the understory. The canopies are so thick that very little light reaches the forest floor. As a result, only a few plants are able to thrive in this area and walking through a tropical rainforest is easy. In some places, more sunlight does filter through to create dense undergrowth. This is called a jungle and it is more commonly found along rivers or in areas which have been cleared in the past.
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Rainforest canopy.
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All tropical rainforests have the same characteristics. Yet each individual range has different species living within it. The biodiversity of these ecosystems is astonishing. According to the National Academy of Sciences, “A typical four square mile patch of rainforest contains as many as 1500 species of flowering plants, 750 species of trees, 125 mammal species, 400 species of birds, 100 of reptiles, 60 of amphibians, and 150 different species of butterflies. In one study, one square meter of leaf litter, when analyzed, turned up 50 species of ants alone”. Only 1% of these organisms have ever been studied. Many of these species are becoming extinct even before scientists have a chance to discover them. Haiti, Bangladesh, India, and Sri Lanka have lost their rainforests already.
According to the Rainforest Action Network, “Rainforests cover 2% of the Earth’s surface, or 6% of its land mass, yet they house over half the plant and animal species on Earth. They originally covered at least twice that area”. The rainforest also provides shelter and food for more than 140 million people of approximately 1000 tribes. To destroy the rainforests is to destroy their homes and way of life.
WHO LIVES IN THE RAINFORESTS?
To name just a few:
- Jaguar
- Harpy eagle
- Howler monkey
- Toucans
- Deer
- Green anaconda
- Three-toed sloth
- Colobus monkey
- Iguana
- Long-tailed hermit hummingbird
WHAT DOES MAN USE FROM THE RAINFOREST?
- Food—coffee, nuts, bananas, spices, vanilla, corn, sugar, cocoa, etc.
- Medicine—According to the World Resources Institute, “One out of four pharmaceuticals used by western chemists comes from a tropical plant”.
- Fuel—Many people in Third World countries rely on the forests for wood (cooking and heating).
- Raw materials—oils, gums, latex, waxes, dyes, and tannins.
WHY ARE RAINFORESTS DESTROYED?
- Logging
- Agriculture
- Population resettlement
- Ranching---beef cattle
- Roads
- Hydroelectric plant and dams
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