2011 year 8 geography - rainforests - deforestation

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Transcript of 2011 year 8 geography - rainforests - deforestation

Rainforests Deforestation

Year 8 Geography- Topic 1 – Global Environments - 2011

Deforestation

Deforestation is the process of

destroying forest areas

According to recent data, between

2000-2005, over 10.4 million

hectares of tropical rainforests

were destroyed each year

Deforestation

Brainstorm why the world’s

rainforests are being cut down

Deforestation

Reasons for Deforestation

Logging Agriculture Population

Pressure Mining

Dam Building

Fire

Deforestation - Logging

Kilometre's and

kilometres of

trees have been

cleared by large

timber

companies with

profit a main

driver

Deforestation - Logging

Deforestation - Logging

Deforestation - Logging

But it will just grow

back so why do

we need to worry?

Deforestation - Logging

But it will just grow back so why

do we need to worry?

It can take 100’s of years for

regrowth and it will never grow

back to its original beauty and

variety of plant and animal species

Deforestation - Logging

Two options for the logger:

1)Clear-Felling which

removes all trees over a

large area

2)Selective Logging

involves loggers selecting

particular trees to be cut

down with the idea to give

the rainforest a better

chance at growing back

Deforestation - Agriculture

Shifting

Cultivation

This involves

farming in one

place for a few

years before

moving on to a

new site

Deforestation - Agriculture

Deforestation - Agriculture

Cash Cropping

This includes

things such as

coffee, rubber

and tobacco

Deforestation - Agriculture

Cattle Grazing

Large areas of rainforest are cleared to become

pastures for cattle.

Most cattle produced is exported to wealthy countries

for use in fast food outlets

Deforestation – Population Growth

Population Growth & Poverty

Limited amounts of rainforest cannot support the

needs of a growing population.

Many people turn to shifting cultivation and the use

of trees as a source of fuel and building material

Deforestation – Population Growth

Deforestation – Mining

Mining

Large sections of rainforest areas are rich in minerals

and precious metals. In response, large areas of

rainforests are cut down and the ecosystem

destroyed.

Deforestation – Dams

Dams

Dams are a serious threat to rainforests. Huge areas

of rainforests are cut down to construct the dam and

large areas are flooded to create reservoirs

Deforestation – Fire

Fire

Loggers cut through the rainforest and set up logging

roads. These roads cut the rainforest into sections

and they dry out. As a result, they are prone to fire

What’s the Impact?

What is the

impact?

How does

deforestation

affect

rainforests?

What’s the Impact?

Did you know that an average of 137

species of life forms are driven into

extinction every day

That’s over 50,000 per year

This means a significant loss of

biodiversity

What’s the Impact?

What’s the Impact?

Did you know that many

indigenous people have

lost their homes as a

result of rainforest

destruction?

Between 1900 and

1950, 87 indigenous

groups in Brazil were

destroyed

What’s the Impact?

What’s the Impact?

What’s the Impact of Deforestation?

Loss of Biodiversity

Soil erosion and loss of nutrients

Loss of homes for indigenous

people

Changes to climate

True or False?

1)Some species of bamboo have been found to

grow up to 91 cm’s per day in the rainforest

2)Trees in tropical rainforests are so densely

packed, that rain falling on the canopy can take up

to 10 minutes to reach the ground

3)The Rafflesia is the world’s largest single flower

and releases a foul smell like rotting flesh