Sec 1 geog unit 3 lesson 2

Chong Boon Secondary School

Sec 1 GeographyUnit 3 Part 2

Uses of Tropical Rainforests

By the end of this section, you will be able to:

1. Explain what is water catchment2. Describe the role of rainforests in

the oxygen cycle3. List and explain the importance of

rainforests

Section objectives

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.

Water catchment

PG 80

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

Online task

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.

Green lungs of the earth

The oxygen cycle

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

Flora and Fauna

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

Factors that encourage diversity in species

Humans who live in the rainforest.

Original inhabitants of the country.

Rainforest provide them with their daily necessities◦Food, clothing, medicine

Indigenous People

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.

Hunter Gatherers

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.

Shifting Cultivators

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.

Source of timber

Tropical rainforests are also known as the world’s largest pharmacy

Source of the world’s medicinesMany plants have yet to be studied for their medical properties.

Medical Application

Turn to Pg 84 of your textbookRead the newsreport by Tom Phillips.

Answer the 3 questions on pg 85 on your own.◦Write the answer down in your textbook.

◦10 minutes

Casestudy reading

1. What is water catchment?2. Describe the role of

rainforests in the oxygen cycle.

3. List and explain the importance of rainforests.

Section Summary

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

Homework