rain forest - melissamonti

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Saving the Rain Forests
By
Sally Morgan
Genre: Expository Nonfiction
Rain Forests:
A rain forest is a special kind of forest that grows in warm, wet places
• Trees are tall and grow close together
• Three types of rain forests are:
• Tropical
• Cloud
• Temperate
Authors Opinion: The future of the rain forest is important to everyone
Tropical Forest
• Grows near equator
• Climate is hot & rain falls
nearly every day!
• EVERGREEN trees – (they
have leaves all year long)
The largest area of rain forest is the Amazon rain
forest
• Located in the Amazon River basin in South
America
• Central Africa, Southeast Asia and Australia also
have tropical rain forests.
Cloud Forests
• These are rain forests that cover mountains in tropical regions
• Up in the clouds and air is cooler - higher up the mountain
• Trees are shorter than those in tropical forests (deciduous trees are here)
• Deciduous trees drop their leaves once a year
Temperate Forests
• Grow farther from the equator where climate is cooler
• There are different seasons
• Some parts of year are cool & others are warm
• Conifer trees needlelike leaves that drop gradually all through year
• Trees covered in mosses & lichens
Found in: Australia
New Zealand
North America
and parts of South America
Rain Forests at Risk
• In the last few years there have been huge fires in Brazil & Indonesia
Millions of plants & animals
• Rain forests are home to nearly 2/3 of the approximate ten million different
types of plants & animals that live on Earth!
Water & Climate
• Water from rain forests is important because the rain forests release so much
water into the air that it affects the climate of the tropics
• Plant roots draw up the water from the ground, a lot of the water evaporates
and helps to form rain clouds.
Rain Forests at Risk – (con’t)
Gases in the Air
• Leaves use energy of the sun to join water & carbon dioxide gas from air
to make food – thus giving off oxygen
• Most living things (including trees) need oxygen to convert food material
into energy for their bodies
• Removing the rain forests cuts down the amount of oxygen in the air
which threatens the lives of many plants & animals
Disappearing Forests
Half of the world’s rain forests have been destroyed to provide timber
or farmland.
It will take centuries for them to grow back
Land for farming
In Central & South America, land that was once forest is now pasture
for cattle.
• In many countries, the best farmland outside the forest is owned
by rich people
• The poorer farmers need somewhere to live so they clear
forestland for farms
• They grow crops and use wood as fuel
• Wood is the only fuel available for cooking and heating
water
Tropical Woods
Used a lot in building
( VALUABLE TIMBER!!!)
In Southeast Asia & Africa, logging for timber is the main reason for clearing the
forests
Timber companies build roads into the forests so they can bring machinery in to cut
down trees & pull out the logs
The logs are exported all over the world to make tables & other furniture
Big Business – Money ! Money! Money!
Huge areas are burned to clear land to plant cash crops
• Cash crops (crops grown for sale) such as coffee, bananas & rubber are grown
instead of fruit & vegetables for local people
* Mining, industrial development, building large dams & tourism are big business
and threaten the rain forests.
Washed Away
• Heavy downpours of rain every day!
• About 6 inches can fall in just a few hours
•
•
•
•
A Huge Sponge
Plants soak up most of the rainwater
It evaporates from the leaves – creating mist & low clouds
Water in clouds falls back on to the forest as rain (RECYCLED!)
Then drains into streams & rivers
Soil Erosion
• If trees are cleared away, there are no roots to hold the soil
• The soil washes into streams and rivers and chokes them up with mud
Less Rain
• With fewer trees, rainwater drains away quicker.
• Less water evaporates so less falls as rain The climate of the rainforest changes
Instead of reliable rainfall
there could be droughts!
Rich Resources
Rain forests are rich in materials used in industry
• Wood is used in building and making furniture
• Rocks beneath the forest may contain oil & metals such as gold, silver & zinc
Logging
• Many rain forests produce hardwood which is tough & long lasting
(makes it good for building and making furniture)
….BUT…..
• The best trees are scattered and hard to get to.
• Loggers damage other trees & the soil, which makes it hard for young trees to
grow.
Mining
• Mining companies clear the rain forests to
reach rock that contains oil & valuable metals
• In doing this, they can remove whole hillsides!
• All this digging produces a lot of waste
material which is usually dumped on nearby
land
• Water running off this waste may pollute
rivers & streams and harm the aquatic life in
them
New Finds
• Scientists believe that they have only found about 1/10th of the animals & plants
in the world’s rain forests
• New species are being discovered every day!
• Many forest plants could be the source of new medicines or foods
New Medicines
• About 1/4th of all modern medicine came originally from rain forests
• Forest people discovered most to these long ago
• Used meds to treat headaches, fevers, cuts, snakebites, toothaches & skin
infections
***** It is important to continue to test new things found in
rain forests because they may help to cure many diseases *****
•
•
Exotic Foods
Rice, coffee, bananas, & peanuts all originally came
from the rain forests
There could be around 75,000 types of edible plants
in the world HOWEVER, we eat only a few 100 of
them!
Why • Our diets could be more varied & healthy if we used
more rain forest plants
Test
Rainforests?
Making Discoveries
• There are some fruits that contain more vitamin C
than oranges
• One tree produces a kind of oil that can be used in
diesel engines
• Some plants contain insecticides (substances that kill
insect pests)
Eco Thoughts
• More than one billion people depend on the water
that falls in the rain forest. They need it for
drinking, cooking & watering crops
In a -4- mile area of rainforest, there can be 1500 species
Of flowering plants, 400 species of birds, 150 species
of butterflies,100 species of reptiles & 60 species of amphibians.
After logging, as many as -3- out of -4- trees left
behind in the forest may have been badly
damaged. It takes hundreds of years for them to
regrow fully
What Can We Do?
• The future of the rain forests is important to everyone
• People and government need to work together to make sure the precious
resource of the rain forests is used well
The Earth Summit
• 1992 – in Brazil
• Politicians & experts from 150 countries discussed biodiversity, importance of
rain forests, and global warming
• Created a biodiversity action plan - listed plants & animals found in their
own countries
• Set up more nature reserves & national parks
• Management of forests in a better way
Rain Forest Charities
• Some charities raise money to use to save
the rain forests.
• Some charities use money to set up nature
reserves to protect wildlife
• We can help by supporting these charities
Challenge
• Find ways for people to live in rain forests
• Find sufficient food in them
• Earn a living from them
• Protect them
• ALL AT THE SAME TIME! !!
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