This document discusses the uses and importance of tropical rainforests. It explains that rainforests play a key role in the water and oxygen cycles by reducing surface runoff and absorbing carbon dioxide during photosynthesis. Rainforests are also incredibly biodiverse, providing habitat for over 2 million species of flora and fauna. They are an important source of resources for indigenous people as well as timber, fuel, medicines, and more. Deforestation threatens these benefits and species.

1. Unit 3 Part 2
Uses of Tropical Rainforests
2016

2.  By the end of this section, you will be
able to:
1. Explain what is water catchment
2. Describe the role of rainforests in the
oxygen cycle
3. List and explain the importance of
rainforests

3.  An area that is drained by a river and the
tributaries (smaller rivers that flow into it).
 Trees in a rainforest reduce surface runoff.
 Rain is dripped into the ground via the
trees.
 Groundwater storage is large in rainforests.
 Impurities in rainwater are filtered by soil
before entering reservoirs.
◦ Seletar and Peirce Reservoirs.

4. PG 80

5.  Visit the website on Pg 80 to learn how
Singapore increased its water catchment from
half to two-thirds of our land surface in
2011.

6.  Rainforests help recycle oxygen.
 In the day, photosynthesis takes place
 Rainforest take in carbon dioxide and
produce oxygen
 This helps reduce the total amount of carbon
dioxide in the environment.
 Human industrial activity releases large
amount of carbon dioxide, we need the
rainforests.
 Rainforests absorb 2.4 billion tonnes of
carbon dioxide in a year.

8.  Flora
◦ Plants species
 Fauna
◦ Animals, insects species
 Rainforest are home to over 2 million species
of Flora and Fauna.
 Many of these species have yet to be properly
studied by mankind.
 Deforestation leads to the loss (extinction) of
many species

9. 1. Ample sunlight in the rainforests
allow for rapid flora growth.
2. The large amount of flora serves
as food for fauna. The
continuous canopy also serves as
a habitat of flora and fauna

11.  Humans who live in the rainforest.
 Original inhabitants of the
country.
 Rainforest provide them with their
daily necessities
◦ Food, clothing, medicine

12. Click on
pictures to
watch videos

13.  People who do not grow food.
 Engage in hunting of animals for
meat by the men.
 Gathering of wild fruits and
vegetation for food by women and
children.

14.  People who grow their own plants for food
and medicine.
 Clearing of small plots of land through
burning.
 Ash from burning provides fertilizer for
crops.
 When land is no longer fertile, it is allowed
to fallow.
 New plot is selected and process is
repeated.

15. Click on
picture to
watch video

16.  Rainforest provide wood for fuel
 Rainforest provide 20% of global
industrial timber
◦ Tropical hardwood (teak, ebony,
mahogany, meranti)
◦ Very expensive and valuable
◦ Durable and strong.
◦ Used for furniture, doors, construction.

18.  Tropical rainforests are also
known as the world’s largest
pharmacy
 Source of the world’s medicines
 Many plants have yet to be
studied for their medical
properties.

19.  Turn to Pg 84 of your textbook
 Read the newsreport by Tom
Phillips.
 Answer the 3 questions on pg 85
on your own.
◦ Write the answer down in your
textbook.
◦ 10 minutes

20. 1. What is water catchment?
2. Describe the role of
rainforests in the oxygen
cycle.
3. List and explain the
importance of rainforests.

21. Review Section 2
Next lesson you will have
a mini test for Section 2