sec 1 - all about geography - chapter 3 - tropical rainforests
TRANSCRIPT
““ ””““ ””All About Geography, Chapter 3, p.72
1. Identify where tropical rainforests are found
2. Describe the characteristics of a tropical rainforest biome
3. Explain the uses and importance of the rainforest
Why/why not?
Why? Why not?
Why? Why not?
““””
How are Tropical RainforestsHow are Tropical Rainforests
from other types of forests?from other types of forests?
FACT!FACT!
Rainforests are very thick and luxuriant forests. They are found in areas with high rainfall and high temperatures. The trees in the rainforest have broad leaves which are evergreen. It is estimated that about half of all the earth’s plant and animal life lives in rainforests.
Tropical Rainforests are found in areas which experience the Equatorial Climate.
These areas are found 20°North and 20°South of the Equator! The average temperatures here are above 26°C and the total annual rainfall is between 1500 to 2000 millimetres (mm)!
Where are tropical rainforests found?
Example of countries with rainforests:
- Mexico- Venezuela- Suriname- Columbia- Brazil- Peru- Bolivia
- Congo- Indonesia- Papua New Guinea
Amazon Basin!
Congo Basin!
South East Asian Countries!
Refer to
p.88
““””
What are the typicalWhat are the typical
of a tropical rainforest?of a tropical rainforest?
Emergent > 50 m
Canopy20 – 30 m
Undergrowth< 20 mStructure of a TRF
Emergent The tallest trees in the
forest. They rise several meters above the canopy.
Key Feature 3:Large buttress roots to
support the tree
EmergentThe tallest trees in the
forest. They rise several meters above the canopy.
Key Feature 1:Tall straight trunks that
can grow > 50m to compete for sunlight
Key Feature 2:Smooth bark
allows water to drain off easily
Buttress roots can grow 1 – 5 metres above the ground
However, they are also shallow (do not grow deep into the ground) as nutrients in the TRF soil is mostly found in the top layer
Canopy20 – 30 m
The CanopyThe Canopy
Also known as the ‘roof’ of the rainforest. This layer is very thick and dense.
Interlocking top crowns of the trees block up to 90% of the sun’s rays.
Numerous vines (lianas) and other ‘cling-on’ plants (epiphytes) can also be found here.
The Canopy LayerViewed from inside
Epiphytes are plants that grow on other plants. Examples include ferns and orchids
The Canopy LayerViewed from inside
Lianas are thick woody vines that climb up tree
trunks to reach sunlight.
Undergrowth< 20 m
Dark and dense Little sunlight reaches the ground
(due to the canopy) Plants in this layer are small and
thin (e.g. fungi, mosses etc) Many dangerous animals can also
be found here!
A voracious eater, it will attempt to swallow anything that moves close to its wide mouth.
When threatened by humans, these frogs will jump and deliver a painful bite
Very small in size, but poisonous enough to kill up to 100 people!
It has one of the most powerful poison known to man, but harmless if left alone.
Also come in red, yellow and green
Both fungi and mosses obtain their nutrients from dead plants and animals.
Some are poisonous. Through their decomposition,
the nutrient cycle is restored.
1
2
3
4
deathdeat
h
death
Emergent > 50 m
Canopy20 – 30 m
Undergrowth< 20 mStructure of a TRF
LeavesoWide and broad – to compete for sunlightoWaxy or hairy surface –
minimizes water lossoDrip-tips – allow excess water to run off easily and prevent growth of bacteria
Fruits and flowers
o Colourful and strong-smelling –
to attract animals to help
disperse the seeds
Can you name some
examples of fruits and
flowers found in the tropics?
““””
Why should we save the Why should we save the world’sworld’s
All About GeographyAll About Geography, p.80 - 85, p.80 - 85
Water Catchment Area
Refers to an area drained by a river and the tributaries
When rain falls on a forest, the water helps it to slowly seep into the ground where it can be stored as groundwater
The forest also helps to filter off any impurities so that the groundwater is kept clean.
Rainforests are responsible for 28% of the world's oxygen!
More than 20% of the earth’s oxygen is generated by the Amazon rainforest alone!
They are vital to the stability of the Earth’s climate
Many unique animals live there…
Pink River Dolphin!
Giant Leaf Frog
Tree Kangaroo
Tapir
Thousands of plants can be found there!No other place on Earth has such rich BIODIVERSITY (the range of plants and animals found in the area)
Over 3000 species have been found to have cancer fighting properties in the Amazon!
