Tropical Rainforest
Tropical rain forests are woodlands around the equator with a lot of vegetation that is evergreen. It is very warm and rain falls throughout the year.
Although only 7 % of the land surface are covered with rainforests , more than half of the world’s plants and animal species live there.
Rainforests are very important for human beings. Plants produce food and medicine and we get industrial products out of some of them. Trees produce timber , help control the earth’s climate and supply us with fresh air.
Despite these advantages, people cut down thousands of square kilometres of rain forest every year.
Climate
Temperatures stay the same the whole year round—about 20 to 30 degrees Celsius.
Around the equator there are two rainy seasons with heavy rainfall — up to 10 metres. When you move away from the equator it gets a bit drier in some months , but there is still more than 2 metres of rain a year.
The weather hardly changes from one day to the next. In the morning it is clear . The sun starts heating up the ground and warm, humidair starts to rise. In the afternoon clouds get blacker and there are thunderstorms for an hour or two before it starts to clear up again .
Most of the rain stays in the rain forest . It evaporates , creates clouds and falls down again.
Rain forest soils are not very fertile because the rain washes out most of the nutritients.
Daily weather cycle in the tropcial rainforest
Structure of the rain forest
Rainforests have four layers.
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The top layer is the canopy. It consists of the tallest trees of the rain forest. They may get over 50 metres tall. But only very fewreach this height. This is the part that gets most of the sunlight.
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The subcanopy is a layer of trees that is below the canopy. More than 70 % of rainforest animals and plant species live in the canopy and subcanopy. Lianas often climb around trees.
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The understory is the shadowy lower area. It has young trees and plants like ferns or palms that do not need much light. Only 1 or 2 per cent of the sunlight reaches the understory.
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The floor has a thin layer of leaves, seeds or fruits and branches that fall from the trees. It decomposes fast and new material takes its place.
When large , tall trees die and fall to the ground they leave a gap in the rain forest. Very quickly, smaller trees take this place and theircrowns grow larger. That’s why the layers of the rain forest always change.
Plants and animals
About half of the world’s plant species can be found in the rain forest. Because it is warm and rains the whole year, forests stay green. Trees lose their leaves andimmediately grow new ones. The rain forest is the home of many plants : lianas, ferns, orchids and many kinds of tropical trees.
Fish, reptiles, birds and insects also live in the rain forest and its rivers. Plants and animals need each other to survive. Insects pollinate the flowers of the rain forest. Animals get food from the flowers’ nectar . Seeds from trees are often taken away by other animals and birds and dropped in far away areas.
Value of the rain forest
People benefit from the rain forest in many ways :
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Economic value
Wood is the most important product of the rainforest. About 80 % of it is used for energy and 20 % is sold to make furniture. The forests produce other valuable goods like fruits, nuts, different kinds of oils and rubber.
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Scientific value
Scientists study the rainforest as an ecosystem. They learn a lot about how plants and animals live together. Tropical plants are used to cure diseases like malaria.
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Environmental value
Rain forests help to regulate our environment. Trees control the water that reaches the ground. They also take up a lot of rain. Much of this water evaporates and gets into the atmosphere again as vapour . Then it turns into rain and comes down to earth. Without rain forests, floodsand droughts would be very extreme. Rainforests also help our atmosphere from becoming too warm.
People of the rain forest
Most of the world’s rainforests are populated by indigenous people. These are people who have been living there for thousands of years . They depend on the rainforests for survival. Some people live in places that you can get to only by boat.
Many people collect fruits, nuts and firewood. They hunt and fish for food to stay alive. They burn down small areas of rainforest and grow crops there. When the soil gets too bad , they go to other places and plant new crops. This method of farming is called shifting cultivation.
Today, the living areas of these indigenous tribes are in danger, because other people have come here to chop down trees, raise cattle or mine gold and silver.
Deforestation
People are destroying the world’s rain forests at a very fast rate. One of the reasons is deforestation. More and more trees are cut down every year because
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the world’s population needs more and more wood
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people in the tropical rain forest need energy. They can’t buy oil or gas because it’s too expensive.
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governments find valuable raw materials in these areas—like iron ore, gold or silver.
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dams are built along tropical rivers.
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big companies get land to grow meat and produce food.
Rainforest burned down in South America
How we can save the rain forests
Many environmental organisations like the World Wildlife Fund , are working to save rainforests all over the world. They help to create national parks or otherprotected areas. But this costs a lot of money and not all governments want to spend it.
It is also important to tell the public how valuable rainforests are and what will happen if they are completely destroyed.
Animals and Plants of the Rainforest
Palm Tree
Palm trees grow in the hot and wet climate of the tropics. They give us food, drink and sometimes building material. Most palm trees are found in southeast Asia, South America and on islands in the Pacific.
There are over 2,000 kinds of palms. They grow straight and tall and most of them carry fruits, like the coconut, which can be up to two feet big.
Rubber Tree
Rubber is one of our most important raw materials. Natural rubber comes from the juice of the rubber tree. It grows best in hot climates. The tree can be about 20 metres tall. It has smooth, shiny leaves. A white, milky fluid comes out of the bark if you cut into it. This is called latex.
Today, most rubber comes from plantations in southeast Asia.
Orchid
Wild orchids grow in places with a lot of rainfall. Most species grow on trunks or branches of trees. In cooler regions, orchids are grown in greenhouses. Most of them grow in a mixture of fascinating colours
Orchid
Piranha
The piranha is a fish with sharp teeth that lives in the lakes and rivers of the Amazon valley. It attacks and eats other fish and water animals. In some cases, it even attacks humans. Piranhas have flat bodies and can grow up to 30 cm long.
Toucan
Toucans are typical birds of the tropical rainforests. They have big and long bills that are brightly coloured , so that they can attractother birds. The largest toucans can get up to 65 cm long. Most of them live in hollow trees.
Gorilla
Gorillas are the largest members of the ape family. They have huge shoulders, long arms and short legs. They may weigh up to 200 kg.
Gorillas live in Africa near the equator. Although most of them live in the lowlands there are some highland types.
People have hunted gorillas for a long time . As a result , they have become very rare and only about 1,000 gorillas live in the wild today.
Words
- advantages = the good sides of something (= Vorteile)
- although =while
- attack =it wants to damage or hurt someone
- attract = to make themselves interesting for other birds
- bark = the outer part of a tree
- basin = an area of land that is lower in the middle. Usually, a big river runs through it.
- benefit = if something helps you
- bill = the hard , pointed mouth of a bird
- branch = part of the tree that grows out from the trunk
- building material = materials like wood or stone , that you use to build huts, houses or buildings
- carry =have, hold
- cattle = cows that are kept on a farm
- chop down = to make a tree fall
- clear up = it becomes sunny again
- consist =made up of
- create = make
- crops = plants like corn, wheat or rice that are grown by farmers and used as food
- crown =top part of
- cure =to make an illness go away
- dam = a wall built across a river. Most dams are built to make electricity
- decompose = to decay
- deforestation = the cutting or burning down of all trees in an area
- depend = if you need the help of something
- despite = the same as “although”
- drought = a long period of very dry weather
- ecosystem =all the animals and plants that live in an area
- environment = the world around us
- equator =line around the middle of the earth which the divides it into two halves
- evaporate = to change from liquid to gas
- evergreen = when a plant or tree does not lose its leaves in the winter
- fern = a plant with green leaves that look like feathers , but with no flowers
- fertile =able to produce crops and other food
- firewood = wood that you collect to make a fire
- flat =even, level, smooth
- flood =a lot of water that covers a place that is usually dry
- fluid = the same as “liquid”
- furniture = large objects in the house that are mostly made of wood , like chairs, tables, cupboards etc..
- gap = a small space between two objects
- hardly = almost not
- height =how high something is
- hollow = an object with a hole inside
- huge = very big
- humid = very wet
- immediately = at once, very quickly
- indigenous = people who have always been in the same place all the time
- iron ore =rock or earth which has iron in it
- juice = a liquid that comes from a fruit, tree or vegetable
- layer =material between two other things
- liana = long vines that grow up trees
- mine = to dig big holes in the earth and get out coal , gold or other things
- mixture = a combination of two or more
- nectar = the liquid that insects collect from flowers
- nutritient = a chemical or food that gives plants what they need to grow
- plantation = a large group of trees that are grown to produce rubber
- pollinate = to give a flower or a plant pollen so that it can produce seeds
- protect = guard, defend
- public =the people
- raise = to look after animals and help them grow, so that they can be sold
- rare = you can’t see it very often or it something doesn’t happen very often
- rate = speed
- raw materials =things that exist in nature and can be used by people, like oil or wood
- reach = get to
- regulate = to control
- reptile = an animal like a snake, whose body temperature always changes
- rise = to go up
- seed = a small hard object that is in a fruit or plant
- shadowy = very dark
- shifting cultivation =farmers grow crops on a piece of land, but only for a short time; When the soil is too bad to grow food they move on to the next piece of land
- shoulders = a part of the body between your neck and your arm
- smooth =flat, soft, with no bumpy parts
- soil = the top part of the earth on which plants grow
- species = a group of animals or plants that are like each other
- straight =not bent or curved
- supply = give
- surface =top layer of an object
- survival =to live on
- survive =to live on after a dangerous situation
- throughout = all over
- timber = the wood that you use to build houses
- tribe =a group of people who are of the same have the same language ; they are often ruled by a leader
- trunk = the thick, middle stem of a tree
- valuable = very important
- vapour =very small drops of liquid that float in the air
- weigh = how heavy something is
- wild = in nature
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