Year 9 Science Term 4 review 4

Challenges
facing the

Murray-Darling

River Basin

Year 9 Humanities

Term 3

1

3

The Murray–Darling Basin is the catchment for
Australia's largest river system. The Murray
and the Darling rivers are Australia's longest
rivers.

The Basin covers an area of more than 1
million square kilometers, which is equal to
14% of mainland Australia and is home to 2.6
million people. The Basin includes:
• 75% of New South Wales
• More than 50% of Victoria
• 15% of Queensland
• 8% of South Australia
• all of the Australian Capital Territory.

The Basin area is the 20th largest river catchment in the world.

Multiple Choice

The Murray Darrling Basin covers more than

• 10 million square km

• 100 square km

• 10 thousand square km

• 1 million square km

Multiple Select

Which states does the Murray-Darling basin go through?

• Western Australia

• Queensland

• South Australia

• Victoria

• New South Wales

Murray-Darling

Basin background

• Compared with other rivers of the world, the rivers of the Basin have carved winding courses across the landscape and are slow flowing, in areas that are very dry, hot and receive little rainfall, which leads to high evaporation rates . The Basin is one of the flattest catchments in the world.

Fill in the Blank

The rivers of the Murray-Darling Basin have carved winding courses across the landscape and are ____ flowing

• The Australian Constitution gives control of water resources to the states, but this makes it complex to administer because it involves cooperation between the four states.

• Since Europeans arrived in Australia, expanded settlements and agricultural activities have significantly affected the health of the river system.

Fill in the Blank

The Australian Constitution gives control over water to the

Importance of the Murray-Darling River Basin

• The Murray-Darling River Basin is Australia’s ‘food bowl’.

• Agriculture (and associated industries) has helped create and continues to support important regional communities.

• One third of all food produced in Australia comes from the MDB and it generates 39% of national income.

• 52% of agricultural, industrial and domestic water used in Australia comes from the MDB (2005 data).

• The Basin produces $22 billion worth of food and fibre every year, feeding the nation and the world.

• Food security is dependent on the health of the basin.

Reorder

Reorder the following

• The Murray

• Darrling basin

• is Australia's

• 'food bowl'

1

2

3

4

• 1
• 2
• 3
• 4

Dropdown

The Murray Darling Basin supports the production of roughly one ​

Select answer

of our food and ​

Select answer

% of our income.

Australia's food security is dependent on the health of the basin.

​+

​=

Fill in the Blank

Australia's food ------- is dependent on the health of the basin.

Key challenges to
Murray-Darling Basin

In spite of the river system being
one of the major river systems of the world, the water flow is the lowest of all the world’s river
systems.

It receives only about six per cent
of Australia’s total rainfall, and over
94 per cent of the water that enters
the system is lost to evaporation.

Environmental challenges exist
even without agricultural activity, so
with agriculture , significantly more
pressure is put on an already fragile
ecosystem.

Water
quality

Salinity

Blue green
algae

Population

growth

Natural
climate

Different
states/
different
policies

Invasive
species

Erosion

Water flow

Precipitation

Multiple Select

Choose any which are key challenges for the Murray Darling basin

• evaporation

• money

• invasive species

• farming

Blue-green algae

.

Blue-green algae

Contaminates the surface
of leaves, fruit and vegetables, causing illness

Contaminated drinking water can cause illness in animals

Reduced productivity of crops

Crops grown to provide feed for livestock may cause illness

Multiple Choice

Blue-green algae contaminates the surface
of leaves, fruit and vegetables, causing ----

• price rises

• pests

• orange spots

• illness

Fill in the Blank

Blue-green algae _______ the productivity of crops

Salinity

.

Less productive, waterlogged
soils where irrigation occurs
cause the water table to rise.

Loss of vegetation leads to increased erosion of stream banks

Surface runoff of salt leads to reduced water quality

An increasing area of non-productive land is due to the presence of surface salts

Hotspot

Where are the salts now that irrigation and land clearing has lifted them?

Multiple Select

How does land clearing effect salinity

• Means you need less water

• Means water rises in the water table

• Salts rise up to the surface

• Means less habitat for animals

Population growth

.

Population growth

Rapidly increasing population needs more food

Loss of farmland and quality fresh water are results of increased urban development.

Increased renewable energy demands increases demand for farmland for biofuels.

Increased land clearing results in loss of topsoil and nutrients

Match

Match the following

• Population growth

• Increased urban development

• More renewable energy

• More land clearing

Need more food

Less land for farming

Need more farms for biofuels

Loss of soil nutrients

• Need more food

• Less land for farming

• Need more farms for biofuels

• Loss of soil nutrients

Match

Match the activities and water pollutants they produce

• Agriculture

• Forestry

• Marine recreation

• Mining

• Urban runoff

fertilisers

sediment

fuel oils and rubbish

heavy metals andacids

chemicals and rubbish

• fertilisers

• sediment

• fuel oils and rubbish

• heavy metals andacids

• chemicals and rubbish