Rain forests: Can we save them?

 prepared by Pran Gupta
April 12, 1999
This beautiful Amazon rain forest is thick with plants, trees, and animals.

What is a rain forest?

Rainforests are some of the most complex ecosystems on the earth. They consist of forests of tall trees in warm climates with plenty of rain. The temperature averages around 80 degrees farenheit year round, so there is no autumn, and they stay green year round. They receive an average of between 65 to over 165 inches of rain per year. Rainforests generally lie in a thick green belt near the equator, and between the tropics of Cancer and Capricorn, all around the earth. There are rainforests in Africa, Asia, Central and South America, and on the islands of the Pacific ocean.

Tropical rainforests contain the most dense combinations and varieties of plants and animals found anywhere on earth. There are hundreds of species of trees, small bushes and plants, and dozens of species of large and small vines. In fact, over 50% of all the different kinds of plants and animals on earth may live in tropical rain forests. They contain insects, mammals, reptiles, birds, and amphibians.

One main feature of the rainforests is the height of the trees and the thickness of the foliage at the top. Rainforest trees commonly grow to heights of over 100 feet! At the top the foliage is thick and green, and is called the upper canopy. It shades out much of the sunlight and creates a special environment below, where plants and animals live in the trees and on the ground. Some plant species, called "epiphytes," actually live on the branches of the trees, without soil. These include algae, moss, ferns, orchids, bromeliads, and even some kinds of cactus!

This South American parrot lives in the rain forest, along with thousands of other birds and animals. To save them we need to save the rain forest. Photo ( Copyright 1998, World Book.

The Forest Beneath the Canopy

Since there is so little light beneath the canopy, trees and plants that grow there have adapted to low light levels. Some plants, such as the epiphytes prefer lower light levels. Tree seedlings can sprout and grow slowly in low light, waiting for a larger tree to fall and open up some sunlight. Then the smaller tree can grow rapidly towards the sky. Without much light, the vegetation beneath the canopy is not thick, and a person can easily walk through the forest.

Rainforest are always very humid. Thundershowers may occur more than 200 days a year.1 Not only does it rain most days, but the trees and leaves give off moisture, in a process called transpiration. Much of the water found in the rainforest comes from this process.

Walking through the rainforest, it is hot and humid and very shady. You would see many different kinds of plants and animals in the trees and on the ground. There are many small streams and rivers.


Rain forests: Can we save them?
F o o t n o t e s :
1 1999 World Climatological Reference, UN Press, New York; pp 178-179.