Focus Area 5A3 Issues in Australian Environments

Land and water management

Syllabus: Land and water management

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Students learn about: At least TWO geographical issues affecting Australian

environments, (one study must include fieldwork):  the geographical processes relevant to the issue  the perceptions of different groups about the issue  individual, group and government responses to the issue  decision-making processes involved in the management of the issue  management of the issue and implications for sustainability, social justice and equity

Syllabus: Land and water management

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Students learn to:

 explain the interaction of the physical and human elements of the environment  recognise the responsibility of the levels of government to the issue  propose actions that promote: ◦ sustainability ◦ ◦ social justice equity  evaluate the success of individuals, groups and the levels of government in managing the issue

Water Management

Introduction

 Every person on Earth depends on land and water.  Water is essential for life, there are no substitutes.

 Land is: ◦ Where we live ◦ ◦ Provides us with most of our food Provides products like minerals, metals and timber.

 People’s social and economic well-being and their health are dependent on land and water ecosystems.

 It is essential for our quality of life that these two resources are managed sustainably so that they will be available for future generations to use.

Lingo List

        Algal bloom Catchment Desalination Great Artesian Basin Grey water Ground water Hydroelectricity Per capita         River regulation Salinity Total catchment management Underground water Water catchment Water quality Water quantity Water table

What's Your Water Footprint?

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Read http://www.connectedwaters.unsw.edu.au

/resources/articles/waterfootprints.html

Then go to http://www.waterfootprint.org/index.php?

page=cal/WaterFootprintCalculator to calculate your own water footprint

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Land Resources

Australia has a land area of about 7.6 million square kilometres. Source Sue van Zuylen, Glyn Trethewy, Helen McIsaac Geography Focus 2 Page 178  A large percentage of the land is arid or semi-arid and not suitable for intensive agricultural production, urban development or industry.

 Regions with wetter climates and good soils suitable for agriculture and supporting populations have consequently experienced intensive use and degradation.

Land Diversity

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Water Resources

Activity – Skills - Water and its Management worksheets 2 & 3.

In Australia, water management is an important issue due to the low and unreliable rainfall combined with high evaporation rates ◦ Little water collects in rivers, lakes and storage areas compared to other continents. Rivers have highly variable flows and droughts are common.

◦ Many Australians are concerned about the overuse, degradation and management of water.

◦ Inappropriate management strategies have contributed to issues like salinity, pollution, algal blooms and water shortages.

 There is an imbalance in the availability of water in Australia. ◦ Water resources are concentrated in northern Australia and Tasmania, which have high rainfall, whereas most of the population lives in the south eastern states of New South Wales, Victoria and southern Queensland. ◦ Freshwater supplies include rivers, streams, wetlands, lakes, groundwater and springs  Australia has the highest water storage capacity per capita in the world at 4000 kilolitres per person ◦ There are 447 large dams that contain 79 000 gigalitres of water when they are full.

◦ Eighty per cent of the water used is surface water. .

◦ ◦ ◦ ◦ ◦ ◦ ◦ ◦ ◦ ◦

Murray Darling Quick Facts

The Murray-Darling river system is a key source of fresh surface water. 3.3 million Australians in SA, Victoria, ACT and NSW depend on it for water Catchment area for the Murray and Darling rivers and their tributaries Total of 23 river valleys Basin area over 1 million square kilometres 14% of total area of Australia Annual average rainfall 530,618 gigalitres 94% of rainfall evaporates; 2% drains into the ground; 4% ends up as runoff Basin generates 39% of the national income derived from agricultural production Produces 53% of Australian cereals grown for grain, 95% of oranges, and 54% of apples Supports 28% of the nation’s cattle herd, 45% of sheep, and 62% of pigs.

http://www2.mdbc.gov.au/about/basin_statist ics.html

The Great Artesian Basin

 The Great Artesian Basin (GAB) is one of the largest artesian groundwater basins in the world. It extends 2400 kilometres (km) from Cape York in the north to Dubbo in the south. At its widest it is 1800 km from the Darling Downs to west of Coober Pedy. With an area of over 1.7 million square kilometres the basin underlies approximately one-fifth of the Australian continent. (See

GAB (Great Artesian Basin)

The GAB stores a huge volume of water that is estimated to be 64 900 million megalitres. It is enough water to fill Sydney Harbour 130 000 times.  Twenty per cent comes from underground sources, particularly the Great Artesian Basin (GAB). The Great Artesian Basin is one of the largest underground water reservoirs in the world. It underlies approximately 22 per cent of Australia — occupying an area of over 1.7 million square kilometres beneath the arid and semi-arid parts of Queensland, New South Wales, South Australia and the Northern Territory.

  Problems with the use of groundwater include declining water availability, rising and falling water tables and salinity.

On 21 February 2011, ABC Four Corners revealed that significant concerns were being expressed about depletion and chemical damage to the Great Artesian Basin as a result of coal seam gas extraction. In one incident, reported in the program, the Queensland Gas Company (QGC) 'fracked' its Myrtle 3 well connecting the Springbok aquifer to the coal seam below (the Walloon Coal Measures) in 2009, in the process releasing 130 litres of a potentially toxic chemical into the Great Artesian Basin At the end of the Triassic period, uplift on the margins of these basins occurred and erosion of these areas led to sedimentation. Throughout the period, sand and gravel was deposited by streams and rivers and clays and clayey sands were laid down by floodplains and lakes. This process produced a profile of alternating layers. As rivers eroded the steeper slopes, the land began to flatten, and deposition in lakes and large floodplains became more dominant. The sandy sediments consolidated to form the permeable sandstone from which the artesian water is now tapped and the clayey sediments became the impermeable layers. Thickness of the combined layers varies from less than 100 metres on the basin extremities to over 3000 metres in the deeper parts. (See Figure 2). During the Cretaceous period (about 100 million years ago), down warping and high sea levels created a shallow sea over much of inland Australia. This sea deposited mainly muddy sediments, which later consolidated, forming the rolling downs that can be seen today. As the Cretaceous period ended, about 65 million years ago, uplift ended sedimentation in the region of the GAB. Further uplifting and erosion resulted in the exposure of the permeable sandstones in the marginal areas of the Basin. This occurred mainly along the western edge of the present day Great Dividing Range. Rainfall began to infiltrate into the sandstones that led to the accumulation of the vast groundwater reserve.

Figure 1—The Great Artesian Basin How the basin was formed

Ref: http://www.derm.qld.gov.au/factsheets/pdf/water/w68.pdf

Over many millions of years, the GAB was created by the deposition of sediments that eventually formed alternating layers of permeable sandstone and impermeable siltstones and mudstones. The deposits occurred in three major depressions; the Carpentaria, Eromanga and Surat basins which together form the GAB.

Figure 2—Generalised cross-section of the Great Artesian Basin Artesian water

Artesian water is underground water confined and pressurised within a porous and permeable geological formation. Formations that store and transmit water are referred to as aquifers. When one of these aquifers is tapped by a bore, artesian water may flow naturally to the surface.

Sustainability, Social Justice and Equity Issues

 Sustainability is the capacity to endure. For humans, sustainability is the long-term maintenance of well being, which has environmental, economic, and social dimensions   Social Justice generally refers to the idea of creating a society that is based on the principles of equality and solidarity, that understands and values human rights, and that recognizes the dignity of every human being Equity is a perception of satisfaction in terms of fair/unfair distributions of resources

How do these apply?

Activity

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Given some of the issues explored via the Murray Darling and GAB write down one example of a social justice, equity and sustainability issue for each region

How is it used?

 80 per cent of Australia’s water is used in the agricultural sector each year. ◦ The bulk is used in irrigating food crops including rice, vegetables, fruit, grapes, sugar, wheat and other grains. ◦ Water is used to improve pastures and provide stock water for dairy cattle and other livestock.

 Settlements may have limited water supply if: ◦ Located in low rainfall areas, ◦ Have inadequate storage or ◦ Experienced extended periods of drought.