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The Amazon Rainforest The Amazon rainforest_ also known as

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					                  The Amazon Rainforest


The Amazon rainforest, also known as Amazonia, is one of the
world's greatest natural resources. Because its vegetation
continuously recycles carbon dioxide into oxygen, it has been
described as the "Lungs of our Planet". About 20% of earth's
oxygen is produced by the Amazon rainforest.
The Amazon rainforest gets its name from the Amazon River.
The Amazon River begins in the Peruvian Andes, and goes east
over the northern half of South America. It meets the Atlantic
Ocean at Belem, Brazil. The main river is about 4,080 miles
long, and lies in the countries of Brazil, Columbia, Peru,
Venezuela, Ecuador, Bolivia, and the three Guyanas. Twenty
eight billion gallons of water flow into the Atlantic every minute
from The Amazon River.
High temperatures and the amount of rain are the same
throughout the year in The Amazon Rainforest. The climate is
warm and humid, with average temperatures around 79° F. The
difference between day and night time temperatures is greater
than those between seasons.


                                   Temp (℃)
       29.5

         29

       28.5

         28

       27.5                                                     Temp (℃)
         27

       26.5

         26
              Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
It rains almost the whole year in the Amazon forest. But two
seasons could be the rainy season and the not-so-rainy season.
                            The rains start just as suddenly as
                            they stop.
                                    The Amazon Rainforest gets about
                                    9 feet of rainwater a year, but 50%
                                    of that can’t get through the foliage
                                    of the trees.




                         Rainfall (mm)
 350

 300

 250

 200

 150                                                     Rainfall (mm)

 100

  50

   0
       Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec




There are many species of plants in the Amazon Rainforest, and
many of them we haven’t even discovered or recorded yet.
Many plants living in the rainforest have somehow adapted to
it. One of the ways in which they have adapted is to grow very
tall; to actually reach the sunlight and live, plants in the
rainforest have to fight against each other for a place in the sun.
Because it is so hot and wet in the tropical rainforests, trees
don’t have thick bark to slow down moisture loss. Instead they
have thin, smooth bark. Most trees in the rainforest have wide
buttress roots. This is to support them as they grow very tall
(sometimes over 200ft) as there is great competition for
sunlight. The leaves of many trees are waxy and have drip tips
to allow water to run off them (so that water does not gather on
leaves and cause them to rot. It also allows water to reach the
roots on the forest floor). Leaf stems are also extremely flexible
to allow leaves to move with the sun to maximise
photosynthesis.
In the rainforest, there are many different species of vines,
ferns and mosses that grow on the trees. Linia is a type of vine,
and this grows up and around a tree to support it and help it
reach the sunlight. Other "strangler" vines will use trees as
support and grow thicker and thicker as they reach the canopy,
strangling its host tree. They look like trees whose centres have
been hollowed out.
Some tropical rainforest plants are carnivorous, or meat-eating.
They have a cavity filled with either nice or nasty smelling
nectar that attracts insects, especially ants and flies. Inside, the
sides are steep and lined with downward pointing hairs. Insects
enter and lose their footing or are prevented from leaving
because of the hairs. Rafflesia, in Indonesian rainforests,
produces the biggest flower in the world.
                  Strangler Vines




Rafflesia
Rainforests have been divided into ‘layers’. The diagram below
shows how they are divided up:




  The layers of the rainforest are named; the Emergent Layer at the top, then the
 Canopy Layer just below. Underneath that is the Understory Layer, and finally the
                                 Forest Floor.



The Ayahuasca vine is a tropical climbing vine, best known for
its psychoactive properties and use in Peruvian shamanic
rituals. Sometimes called "the vine of the dead," this thick-
rooted plant grows long leaves and small flowers. The
Ayahuasca receives its psychoactive properties from the
chemical harmaline, a compound that stimulates the nervous
system, produced naturally in the vine.
Tohe is a small tree with large, bell-shaped white flowers that
give off a strong perfume at night. This plant is a natural source
of atropine and scopolamine. Atropine was used by Italian
people in the past to dilate their pupils, creating the mysterious,
wide-eyed look such as found in Leonardo da Vinci's "Mona
Lisa." However, excessive use often led to madness, and the
fashion trend went out of style. Atropine is used today to
control muscle spasms, for example when setting broken bones,
and is found in medicines such as Lomotil. Scopolamine, also
found in this plant, was once given to women during labour.
Achiote or Annato is a small tree that produces a spiny fruit
with waxy reddish-orange seeds that are used as natural
colorants in foods and cosmetics around the world. The native
people of the Amazon first used Achiote as a bright red paint for
adorning the face and hair. Achiote is cooked with sap from the
rubber tree to make a durable latex paint that sticks to the skin
for several days.




     Animals, birds, fish and insects of the Amazon
I am going to tell you about two species of animal, one species
of bird, one of fish and one of insect.
The Poison Arrow Frog
This frog gets its name from the native Amazonians. They use
the poison of this frog to go on the tips of their spears. They
then use these to hunt. The poison frog is normally small
enough to sit on a penny! Poison frogs are brightly coloured so
to warn predators they are poisonous. Poison arrow Frogs eat
insects and live on the understory of the forest floor.
Bushmaster
The bushmaster hunts small animals that scavenge on the
forest floor. It is a venomous snake, which means it injects
poison when it bites. The bushmaster is one of the most feared
snakes in South America. Its bite can kill a person within
hours. Luckily the snake is shy, and not often seen.


Toucan
A toucan’s beak is very light, because it is hollow, and each
toucan’s beak is patterned differently, so they can tell one from
the other. Their beaks are made from the same material as our
fingernails, Keratin. Toucans live in small flocks and are very
playful.


Tambaqui
The Tambaqui, also known as the Black Pacu, can grow to a
ginormous 3 ½ feet and can weigh over 60 pounds! This
species of fish is a freshwater fish, found mainly in the Amazon
River. This species is usually solitary. Adults stay in flooded
forests during the first 5 months of flooding and consume fruits
and grains. This species feeds on zooplankton, insects, snails
and decaying plants.
Wolf Spider
The Wolf spider is a predatory spider that normally feeds off
small insects, crickets, or other spiders. This spider has adapted
to life in the Amazon Rainforest, one way being that the spiders
carry young on their backs to prevent them being washed away
by the forest floods.
Pictures:




                         Poison arrow Frogs




                                                            Toucan


            Bushmaster


                                              Wolf spider




 Tambaqui
                  The Cycle of the Forest Floor
The forest floor is the lowest layer and almost no plants grow
here. Only about 2% of the sunlight filters through. The floor is
littered with decomposing vegetation and organisms that are
broken down into usable nutrients. Tree roots stay close to the
surface to suck up these nutrients. So, despite all of its
abundant richness, The Amazon's giant trees grow in really
poor quality soil. The top two inches of soil contains 99% of the
nutrients. Nine tenths of the forest's energy are in the leaves of
the trees themselves. The forest floor is a porous mass that
prevents minerals and nutrients from being washed away and
lost. As soon as a tree falls, or a creature dies, decomposers
begin to turn it into a food source and mulch. The vegetation to
renew the cycle quickly absorbs the nutrients that are released.
This is the tightest, most efficient ecosystem in nature. The
destruction of one part of the system can spell the destruction
of the whole system.

				
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posted:8/15/2011
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