The destruction of the Aral Sea ecosystem has been sudden and severe.
Beginning in the 1960s, agricultural demands deprived this large Central
Asian salt lake of enough water to sustain itself, and it has shrunk rapidly.
Uzbekistan, Kazakhstan, and other Central Asian states used this water
to grow cotton and other export crops, in the face of widespread environmental
consequences, including fisheries loss, water and soil contamination,
and dangerous levels of polluted airborne sediments.
The Aral Sea is one of the greatest environmental catastrophes ever recorded.
Humans have made use of the waters of the Aral basin for thousands of
years, borrowing from its two major rivers: the Amu Darya, which flows
into the Aral Sea from the south; and the Syr Darya, which reaches the
sea at its north end. The Kara Kum Canal opened in 1956, diverting large
amounts of water from the Amu Darya into the desert of Turkmenistan, and
millions of hectares of land came under irrigation after 1960. While the
sea had been receiving about 50 km3 of water per year in 1965,
by the early 1980s this had fallen to zero. As the Aral shrank, its salinity
increased, and by the early 1980s commercially useful fish had been eliminated,
shutting down an industry that had employed 60 000.
|Photo above shows an abandoned fishing boat
in what was once the Aral Sea. Satellite images below show how the
sea shrank between 1973 and 1999
The declining sea level lowered the water table in the region, destroying
many oases near its shores. Over-irrigation caused salt build-up in many
agricultural areas. By the beginning of the 1990s, the surface area of
the Aral had shrunk by nearly half, and its volume was down by 75 per
cent. Winds picked up sediments laced with salts and pesticides, with
devastating health consequences for surrounding regions (see also box).
|Landsat data: USGS/EROS Data Center
Compilation: UNEP GRID Sioux Falls
Photo: UNEP, Topham Picturepoint