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Rainforests Rainforest- a hot humid jungle, mostly found near the equator Equator- an imaginary line around the center of the Earth Many tribal people have called the rainforest home for hundreds and thousands of years. • They’ve taught us about many of the medicines and foods we use today. • They know how to find and use wild plants. A rain forest has a great diversity, or variety, of plants and animals. • In fact, a rain forest has more species of plants and animals than any other ecosystem on Earth. Many of the plants from the rainforest are used for medicine. • One-fourth of the drugs that you can buy at the drugstore have products that come from the rainforest. It is almost always raining in a rainforest. • Rainforests get over 80 inches of rain each year. • The rain is evenly distributed throughout the year in a tropical rainforest. The temperature in a rainforest never freezes and never gets very hot. • The range of temperature is usually between 75-80 degrees Fahrenheit. The soil of a tropical rainforest is only about 3-4 inches thick. • Thick clay lies underneath the soil. • Once damaged, the soil of a tropical rainforest takes many years to recover. The Forest Floor- the ground floor of the rainforest • The Forest Floor is a fairly open area, carpeted with moss and decaying leaves. • Small plants that need little light, such as ferns and moss grow here. The Forest Floor, continued • Higher up there is a dense ceiling of leaves and branches that blocks out most of the sunlight. • The leaves also keep rain and wind from reaching the forest floor. The Forest Floor, continued Most of the forest floor inhabitants are decomposers that live on leaf litter and other debris. The Forest Floor, continued On the forest floor of a rainforest in Central America, you might see: • an anaconda • an armadillo • a poison arrow frog • a wood turtle • a fer-de-lance • a jaguar • a caiman • army ants • leafcutter ants • flightless birds The Understory- the next layer above the forest floor • The Understory is a tangle of shrubs, young trees, palms and woody plants that can grow in the shade of the taller trees. The Understory, continued • The leaves of many of the plants in the Understory are especially large, so that they can absorb as much sunlight as possible. • The plants in this layer of the forest rarely grow higher than twelve feet. The Understory, continued In the Understory of a rainforest in Central America you might see: • bats • snakes • birds • a red-eyed tree frog • an iguana • a tarantula • spider monkeys • a jaguar • insects The Canopy- the third layer from the bottom • Trees as high as 100 feet form a continuous green roof over the forest below. • This roof is like a canopy, or an umbrella. The Canopy, continued • This layer gets much of the rainfall, and it keeps the rain from falling on the Understory. • There is abundant food and sunlight for thousands of animals and plants. The Canopy, continued In the canopy of a rainforest in Central America, you might see: • three-toed sloths • toucans • parrots • macaws • spider monkeys • howler monkeys • butterflies • snakes • orchids • large-leafed vines • hummingbirds The Emergent Layer- the top level of the rainforest • This layer has trees that grow to heights of 250 feet. • These trees receive the full brunt of the hot sun, wind and rain. • They often have thick, waxy leaves to help them retain water and protect themselves from the sun and wind. The Emergent Layer, continued In the Emergent Layer of a rainforest in Central America, you might see: • a harpy eagle • other birds of prey Rainforests are very important. • They recycle and clean water. • The trees and plants remove carbon dioxide from the atmosphere and store it in their roots, stems, leaves and branches. Many of our favorite foods and plants were discovered in rainforests. • Rainforest plants are used to make such products as skin lotion, herbal tea and life-saving drugs. • Cashew nuts, bananas, pineapple, cucumber, cocoa, coffee, vanilla, lemons and coconuts were originally from rainforests. Rainforest Benefits Table Helping the environment Community resources -source of carbon -clean and regular water -drives water and climate -fresh air cycles -tourism -helps stop flooding -recreation -prevents erosion -genetic resources -replenishes groundwater -scientific discoveries -animals and insects -education pollinate plants -source of plants for -plants feed animals horticultural industry -animals eat insect pests -food -habitat -pharmaceutical products -refuge for rare species -hydroenergy -breaks down waste -shade and shelter -soil fertility Personal enjoyment -serenity -scenic views -bushwalking -bird watching -camping -lifestyle -sense of place -national identity -cultural identity -sense of history However, rainforests are threatened. • Rainforests used to cover 14% of the Earth’s land. • Now they cover less than 6%. Rainforests are being destroyed at a rate of about 75 million acres per year. • Trees are being used for their wood. • Land is being cleared for roads, farming and grazing. The destruction of the rainforests is affecting the Earth’s climate. • The burning of rainforests releases carbon dioxide. • With fewer trees to take in carbon dioxide and transpire water back into the air, the Earth’s warmth could be trapped inside a growing layer of these gases. Flooding is another threat. • Without the protection of rainforest plants, soil is washed away by rain and wind. • Without vegetation to slow the rain down, it rushes into streams and rivers, causing them to rise and flood vast areas. The people are forced to leave the rainforests. • They can no longer eat the food they found in the forest. • They are exposed to new diseases that were not in the forest. Many animals can only survive in the rainforests. • If their homes are destroyed, they will become extinct forever. Many people are working hard to save the rainforests. One way is to create protected places called reserves. Selective cutting is done in some places. • This means that loggers and farmers can cut down certain trees, but others must be left to grow. Extractive reserves could also help. • In these reserves, people are allowed to take only limited amounts of fruit, plants, nuts, latex for the production of rubber, and other natural products.