Tropical Rain Forests
Rainforests are very dense, warm, wet forests. They are havens for millions of plants and animals.
Rainforests are extremely important in the ecology of the Earth. The plants of the rainforest generate much of the Earth’s oxygen. These plants are also very important to people in other ways; many are used in new drugs that fight disease and illness.
Areas in Africa, Central and South America, and Southeast Asia are dense with green growth,
unusual insects, colorful birds, and exotic animals. From these rain forests people harvest
beautiful wood, delicious fruits and nuts, and powerful medicines. A single hectare of Amazon rain
forest in Brazil, for example, might support as many as three hundred different types of woody
plants, a great range of biodiversity.
All rain forests share certain characteristics. They grow in very wet, humid places where the
annual rainfall exceeds 1.000 millimeters. Also they have very closed canopy. Because of this, as
little as one or two percent of the sun light reaches the floor. Another characteristic of most
tropical rain forests is poor, thin soil. Only forests in volcanic areas might have somewhat better soil. Rain forests are being eliminated for timber, minerals, agriculture, and human settlement. Other motives, such as the desire to conquer nature or to control unoccupied territory, also are factors in deforestation.