rainforests
DESCRIPTION
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. - PowerPoint PPT PresentationTRANSCRIPT
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, continuedOn 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, continuedIn 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, continuedIn 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 Personal enjoyment -source of carbon -clean and regular water -serenity -drives water and climate -fresh air -scenic views cycles -tourism -bushwalking -helps stop flooding -recreation -bird watching -prevents erosion -genetic resources -camping-replenishes groundwater -scientific discoveries -lifestyle -animals and insects -education -sense of place pollinate plants -source of plants for -national identity -plants feed animals horticultural industry -cultural identity-animals eat insect pests -food -sense of history -habitat -pharmaceutical products-refuge for rare species -hydroenergy -breaks down waste -shade and shelter -soil fertility
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.