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Aral Sea

Current situation



Comparison of the North Aral Sea before (below) and after (above) the construction of Dike Kokaral.



Abandoned ship near Aral, Kazakhstan



A former harbor in the city of Aral, Kazakhstan


The sea's surface area shrank by approximately 60%, and its volume by 80%. In 1960, the Aral Sea was the world's fourth-largest lake, with an area of approximately 68,000 km² and a volume of 1100 km³; by 1998, it had dropped to 28,687 km², and eighth-largest. Over the same time period its salinity has increased from about 10 g/l to about 45 g/l. As of 2004, the Aral Sea's surface area was only 17,160 km², 25% of its original size, and still contracting.
Even the recently discovered inflow of submarine groundwater discharge into the Aral Sea will not in itself be able to stop the desiccation. This inflow of about 4 billion cubic meters per year is larger than previously estimated. This groundwater originates in the Pamirs and Tian Shan mountains and seeks its way through geological layers to a fracture zone at the bottom of the Aral Sea.
In 1987, the continuing shrinkage split the lake into two separate bodies of water, the North Aral Sea (the Lesser Sea, or Small Aral Sea) and the South Aral Sea (the Greater Sea, or Large Aral Sea); an artificial channel was dug to connect them, but that connection was gone by 1999 as the two seas continued to shrink. In 2003, the South Aral further divided into eastern and western basins; the evaporation of the North Aral has since been partially reversed.
Work is being done to restore in part the North Aral Sea. Irrigation works on the Syr Darya have been repaired and improved to increase its water flow, and in October 2003, the Kazakh government announced a plan to build a concrete dam (Dike Kokaral) separating the two halves of the Aral Sea. Work on this dam was completed in August 2005; since then the water level of the North Aral has risen, and its salinity has decreased. As of 2006, some recovery of sea level has been recorded, sooner than expected.[3] "The dam has caused the small Aral's sea level to rise swiftly to 38 m (125 feet), from a low of less than 30 m (98 feet), with 42 m (138 feet) considered the level of viability."[4] Economically significant stocks of fish have returned, and observers who had written off the North Aral Sea as an environmental catastrophe were surprised by unexpected reports that in 2006 its returning waters were already partly reviving the fishing industry and producing catches for export as far as Ukraine. The restoration reportedly gave rise to long absent rain clouds and possible microclimate changes, bringing tentative hope to an agricultural sector swallowed by a regional dustbowl, and some expansion of the shrunken sea.[5] "The sea, which had receded almost 100 km south of the port-city of Aralsk, is now a mere 25 km away." There are plans to build a new canal to reconnect Aralsk with the sea. Construction is scheduled to begin in 2009, by which time it is hoped the distance to be covered will be only 6 km. A new dam is to be built based on a World Bank loan to Kazakhstan, with the start of construction also slated for 2009.[6]
The South Aral Sea, which lies largely in poorer Uzbekistan, was largely abandoned to its fate. Projects in the North Aral at first seemed to bring glimmers of hope to the South as well: "In addition to restoring water levels in the Northern Sea, a sluice in the dike is periodically opened, allowing excess water to flow into the largely dried-up Southern Aral Sea."[7] Discussions had been held on recreating a channel between the somewhat improved North and the desiccated South,[3] along with uncertain wetland restoration plans throughout the region, but political will is lacking. Uzbekistan shows no interest in abandoning the Amu Darya river as an abundant source of cotton irrigation, and instead is moving toward oil exploration in the drying South Aral seabed.[8] Vast salt plains [9][10] exposed with the shrinking of the Aral have produced dust storms,[11] and making regional winters colder and summers hotter.[12] Attempts to mitigate these effects include planting vegetation in the newly exposed seabed. In the Northern Aral, recently higher sea levels have slightly moderated these effects in some areas, and the spring season now sees long-missing rainfall.[8]
In January 1994, the countries of Kazakhstan, Uzbekistan, Turkmenistan, Tajikistan and Kyrgyzstan signed a deal to pledge 1% of their budgets to helping the sea recover. By 2006, the World Bank's restoration projects especially in the North Aral were giving rise to some unexpected, tentative relief in what had been an extremely pessimistic picture.[13]

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