Issues

Political opinion - marketed and priced.

Social - human right.

World water gap between rising demands and dwindling supplies:

Global population growth
Economic development - RICs
Rising standards of living
Climate change

Water supplies are spread unevenly. 2/3 of the world receive less than 25% of worlds annual rainfall = scarcity. This made worse as they're generally in LEDCs which lack the capital to extract the water. Other areas have a water surplus.

There is an imbalance in usage - MEDCs use 10x more per head than LEDCs.

Pollution of water supplies - MEDCs, manufacturing and agriculture.

Areas of concern include Middle East, sub-Saharan Africa and SE USA.

What physical factors determine the supply of water?

Precipitation - doesn't fall evenly. Areas can get rainfall regularly (equatorial areas like the rainforest), whereas other gets irregular rainfall (monsoon prone areas and Sahel).

Temperature - higher temperature means higher evaporation rates.

Shape of land - mountainous areas have high levels of precipitation.

Rock type - impermeable soils offer storage opportunities which prevents evaporation loss.

Location - closer to the sea means greater chance of rainfall, unless near a cold ocean current (G3 Deserts 1.1).

How does human activity influence the supply and demand?

Depletion of supply - Aral Sea (Kazakhstan) extracted water and a faster rate than it was being replenished = shrunk in size to 10% of original size - damaged local economy, communities and ecosystem UNSUSTAINABLE.

Population growth

Rising standards of living

Migration - strain on local water supplies e.g. tourism in Southern Spain.

Economic development - RICs have to maintain agriculture, growing industry and domestic industry through urbanisation.

=

Untreated sewage disposal in LEDCs = water-borne diseases like cholera
Chemical fertilisers contaminate groundwater and rivers.
Industrial waste like heavy metals and chemical leftovers give the water supply toxins.

How can the water supply and demand be managed sustainably?

Management of supplies

INCREASE STORAGE CAPACITY AND SUPPLIES - construction of dams and technology that catches rainwater in tanks. Dams have led to some rivers storing water that exceeds the annual flow e.g. Colorado, which has meant a lack of supply near the mouth. However, dams offer a multi-purpose - irrigation, flood control and HEP. Yet cause environmental destruction. African countries can benefit from small scale dams which involve a lower cost, community participation and less of an environmental impact.
WATER TRANSFER SCHEMES - diversion f water from one drainage basin to another. Controversial as it involves large scale and high tech involvement. May lead to long-term un-sustainability as encourages more development in water deficit areas.
GROUNDWATER SOURCES AND REPLENISHMENT - Long Island, New York has faced groundwater over abstraction so new projects of development legally have to collect rainwater to replenish groundwater supplies.
DESALINATION - conserves fresh water supplies for future generations. Recent breakthrough in technology has led to a more cost effective and less energy intensive method. However, it is still extremely costly and creates a major ecological impact on marine life as salt concentrations in the sea rise = effect of food chain and corals.

Management of demands

AGRICULTURE:

'More crop per drop initiative' - automatic sprinklers and advanced drip irrigation e.g. Israel's smart irrigation.

Recycled urban water usage for agriculture has a low cost.

NGOs - WaterAid - Magic Stones.

GM are pest, disease and salt tolerant.

Murray Darling river basin - government has limited amount of water that can be extracted from the surface and the ground to 10%. Government has bought land to prevent over use by farmers.

Hydroponics - drip fed nutrients and water, reduced growing time means less water and soil usage. Difficult for LEDCs due to cost aeroponic is similar.

Plastic sheeting over crops - UK and Spain. Reducing water usage as water is trapped from plastic sheeting and falls back down on crops.

Industry:

20% of water use and if left unsustainable the global economy will falter.

Rapid industrialisation, especially in LEDCs has led to the contamination of water supplies.

TNCs have tried to reduce water consumption - increased recycling of water - laws prohibiting use of groundwater and rising costs of water.

Domestic - mainly in MEDCs where standards of living are higher and RICs through urbanisation.

Social approach - change attitudes and lifestyle e.g. installing water metres instead of fixed tariffs. Smart meters increase when temperatures are higher and rain is scarce (will companies be trusted to relier prices?). Rain harvesting in gardens. Purchasing appliance that are water efficient - discounts. Ban activities that use water e.g. car washes and certain times.

Singapore has filtration systems that catch rainfall and rear sewage water. Psychologically hard to drink.

Fixing leaks from broken main (is it negative as water gets replenished into groundwater?) encouraged through subsidies or rising prices if private. Treat and reuse industrial and waste water.

Can sustainable water supplies be maintained in the future?

People in LEDCs will suffer greatest.

Water consumption needs to decrease in all sector. Food production needs to occur in areas where there is a water surplus and distribute production evenly. Agricultural needs scientific investment e.g. to make seeds demand less water. Globally educated the importance of a sustainable water supply. Water prices to increase and highlight conservation and recycling. Water extraction must be monitored.

Are TNCs and governments prepared to invest into LEDCs?

If this does occur there will be social implications that are unacceptable - e.g. closing of golf courses and swimming pools won't be socially accepted.

Other solutions may have environmental impacts e.g. construction of dams.

Must be a international and political agreement that water is necessity to all that must be managed sustainably for future demands - is this possible? No, not all countries are stable to co-operate, blinded by short-term prosperity and may be no initiative to help other countries.

	Creado por 09shor1r hace casi 9 años

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G4 - Sustainability