the aralsea
Post on 12-May-2015
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The ARAL SEA
How poor water management has had disastrous environmental, economic
& social consequences.
Location
• The Aral Sea lies on the border of Kazakhstan & Uzbekistan, in Central Asia.
• It is part of what was until 1991 the old Soviet Union.
• It was the World’s 4th largest inland sea.
Location• The Aral sea is in the
middle of the Central Asian Desert.
• Summer temperatures rise to over 40oC.
• The Aral Sea is fed by 2 rivers Syr Dar’ya & Amu Dar’ya. These rivers rise in the mountains to the South.
• There is no outlet river.
The Problem• The Aral Sea is
gradually shrinking & drying up.
• The sea has now divided into 2 smaller seas, shortly to be 3.
• Why?
Causes• In one word – Cotton
• During the Soviet era Uzbekistan was designated as a major cotton growing region of the USSR. Cotton is known as “white gold” & is highly profitable to grow.
• The Fergana Valley became a huge cotton growing area.
Causes• To make cotton grow in a desert large quantities of water are needed (Irrigation).
• Dams were constructed on the rivers & canals diverted the water to the cotton growing farms.
• This reduced the flow of water reaching the Aral Sea.
The Second Problem
• The water quality in the Aral Sea began to decline rapidly
Causes
• The sea became saltier due to evaporation.
• As the sea shrank the remaining salt was concentrated in less water
Causes• More serious was
pollution from a range of toxic chemicals.
• Large quantities of fertilizer, insecticides, herbicides, defoliants etc were applied to the cotton.
• These chemicals were returned to the rivers with the remaining irrigation water & eventually ended up in the Aral Sea.
Impacts• The wetlands of the river deltas dried out, drastically affecting the wildlife of the area.
• Large areas of the former Aral Sea were reduced to barren lifeless salt plains.
• The fish numbers & the birds which fed on them declined rapidly.
ImpactsOnce prosperous seaside villages were left “high & dry” many kilometres from the receding sea this caused further problems.
• Local wells have dried up as the water table has dropped.
• The fishing industry collapsed.
• Fish processing factories closed or had to be supplied from outside areas.
• Unemployment rose rapidly, people began to migrate away from the area.
Impacts
As the sea shrank boats were left “high & dry” the area is now littered with rusting hulks.
• Perhaps the biggest problem has been a decline in the health of the local inhabitants.
• The chemicals have seeped into the local water supply causing a wide range of health problems such as cancer, tuberculosis, deformities in babies, liver & kidney failure, anaemia, lung disease & high infant mortality etc.
Signing up for health care
A TB sufferer
Polluted water
Infant Mortality & childhood illnesses have increased.
The remaining Issues• The scheme is no longer under the control of one government.
International co-operation is required to reach sustainable solutions.
• Local populations are in desperate need of safe drinking water.
• The sustainability of growing cotton under irrigation in desert regions needs to be considered. Economic activities that are less dependent on large quantities of water need to be considered.
• Agricultural efficiency needs to be reviewed. There are significant loss of cotton and rice in storage and transpiration. Crop rotation and appropriate technologies need to be used to improve efficiency.
• Irrigation systems need to be redesigned to reduce water loss and the allocation of water needs to be rationed.
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