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The destruction of the Aral Sea is now a wellknown example
of unsustainable development. Atlases used to describe the
sea as the world's fourth largest lake, with an area of 66
000 km2 and a volume of more than 1 000 km3.
Its waters supplied local fisheries with annual catches of
40 000 tonnes, while the deltas of its tributaries hosted
dozens of smaller lakes and biologically rich marshes and
wetlands covering 550 000 ha.
In the 1960s, planners in the former Soviet Union assigned
Central Asia the role of supplier of raw cotton. Irrigation
was imperative, and the Aral Sea and its tributaries seemed
a limitless source of water. Irrigated land was expanded from
about 4.5 million ha in 1960 to almost 7 million ha in 1980.
The local population also grew rapidly, from 14 million to
about 27 million in the same period, while total water withdrawal
almost doubled to an annual 120 km3, more than
90 per cent of it for agriculture.
The result was the collapse of the prevailing water balance
in the basin. Waterlogging and salinization eventually affected
about 40 per cent of irrigated land. Overuse of pesticides
and fertilizer polluted surface water and groundwater, and
the delta ecosystems simply perished: by 1990, more than 95
per cent of the marshes and wetlands had given way to sand
deserts, and more than 50 delta lakes, covering 60 000 ha,
had dried up.
The surface of the Aral Sea shrank by one-half and its volume
by three-quarters. The mineral content of the water has increased
fourfold, preventing the survival of most of the sea's fish
and wildlife. Commercial fishing ended in 1982. Former seashore
villages and towns are now 70 km from the present shoreline.
Communities face appalling health problems. In Karakalpakstan,
Uzbekistan, drinking water is saline and polluted, with a
high content of metals that causes a range of diseases. Over
the past 15 years, there has been a 3 000 per cent increase
in chronic bronchitis and in kidney and liver diseases, especially
cancer, while arthritic diseases have increased 6 000 per
cent. The infant mortality rate is one of the world's highest.
Five newly independent Central Asian states have now established
a joint commission for water coordination. Several international
organizations and bilateral agencies are providing assistance,
and an International Fund for the Aral Sea and the Interstate
Council for the Aral Sea Problem have been set up to coordinate
initiatives.
The Central Asian republics have decided to focus on demand
management, aiming to reduce water withdrawal by raising irrigation
efficiency. The primary objective is to satisfy crop water
requirements. Total water withdrawal in the basin has now
stabilized at 110-120 km3/year but environmental
degradation continues.
Source: FAO 1998
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