Aral Sea(redirected from Voz Island)
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Aral Sea (ărˈəl), salt lake, SW Kazakhstan and NW Uzbekistan, E of the Caspian Sea in an area of interior drainage. To the north and west are the edges of the arid Ustyurt Plateau; the Kyzyl Kum desert stretches to the southeast. As recently as the 1970s it was the world's fourth largest lake, c.26,000 sq mi (67,300 sq km) in area and c.260 mi (420 km) long and c.175 mi (280 km) wide. Fed by the Syr Darya and Amu Darya rivers, it was generally very shallow, attaining a maximum depth of c.180 ft (58 m). In the 1950s the Soviet Union decided to cultivate cotton in the region, and since the early 1960s the Syr Darya and Amu Darya have been used for large-scale irrigation, causing a drop in the flow of freshwater into the sea. The sea is, as a result, now greatly reduced. Since 2009 the only areas of the lake permanently filled with water have been in extreme W and N portions of its former lakebed, about a tenth or less of its former size in area.
The sea formerly supported local fishing and was navigable from Moynaq (Muinak) to Aral. As the Aral has retreated from its former shores, due to the combined effects of evaporation and water diversion, major environmental problems resulted. The quality of the remaining water deteriorated as the concentration of salts and agricultural chemicals increased, increased salinity and toxicity killed the fish, and the health of those living along the shore suffered, in part from duststorms carrying contaminated former lakebed soil. Regional weather has been affected as well, becoming harsher as the sea's moderating climatic influence has diminished. Vozrozhdeniye, the site of a Soviet germ warfare waste dump, is a former island that is no longer isolated from the surrounding region; in 2002 the United States and Uzbekistan cleaned up the site.
Geologically separate from the Caspian Sea since the last Ice Age, the Aral Sea was once only slightly saline. Mentioned in Arab writings of the 10th cent., it was called the Khwarazm (or Khorezm) Sea by later Arab geographers. It was reached in the 17th cent. by Russians, who called it the Sinyeye More (Blue Sea). The United Nations has estimated that what remains of the sea will essentially disappear by 2020 if nothing is done to reverse its decline. The Kok-Aral Dam (completed 2005) was constructed to enclose the small northern section (in Kazakhstan), which has revived, but it is a fraction of the former sea, and further increases in the northern section's size are limited by the height of the dam. Portions of the former lakebed have been planted with salt-tolerant trees to stabilize the contaminated soil.
a salt lake in the southwestern Asiatic part of the USSR. The sea’s name is derived from the Turkic word aral, which means island. This was the original name of the region near the mouth of the Amu Darya, and later, of the entire lake. The sea has no outlet and lies 53 m above sea level. Its area with the islands is 64,500 sq km. It is 428 km long and 235 km wide, and the area of the basin is 690,000 sq km. The average volume of water is approximately 1,000 cu km. The depression of the Aral Sea formed as a result of the flexure of the earth’s crust in the Upper Pliocene. The terrain of the sea bottom is leveled. The average depth is 20–25 m, with the greatest depth being 67 m. There are more than 300 islands in the sea, occupying 3.5 percent of its area. The largest islands are Kokaral (Kugaral), Barsakel’mes, and Vozrozhdenie. The northern shore, which is high in some places and low in others, is broken by deep bays. The eastern shore is low and sandy with a large number of shallow bays and off-shore islands. The southern shore is formed by the Amu Darya delta. The western shore, which is practically unbroken, is formed by a precipice of the Ustiurt Plateau, with elevations of up to 250 m.
The two largest rivers of Middle Asia—the Amu Darya and the Syr Darya—empty into the Aral Sea. The climate is continental. The average temperature of the air varies from 24° to 26°C during the summer and from -7° to - 13.5°C in the winter. The annual precipitation is approximately 100 mm. The sea’s water balance is maintained as follows: precipitation, 5.9 cu km; continental runoff, 54.8 cu km; and evaporation, 60.7 cu km. Seasonal variations in the level average 25 cm, and long-term (centuries-long) variations reach 3 m. At the end of the 1950’s, the level of the Aral Sea began to drop perceptibly as a result of extensive use of the waters of the Amu Darya and Syr Darya for irrigation.
The water’s surface temperature ranges from 26° to 30°C in the summer and falls below 0°C during the winter, when ice forms in all parts of the sea. The salinity far from the mouths of the rivers is 10–11 parts perthousand, increasing to 14 parts per thousand at the southeastern shores. The water is transparent to a depth of 25 m. The currents form eddies, which move in a clockwise direction. The fish of the Aral include sturgeon, carp, barbel, roach, ide, and asp. The sea is navigable for about seven months. The chief ports are Aral’sk and Muinak.
The shores of the Aral Sea are sparsely populated. The main occupation of the local inhabitants is fishing and, to a lesser degree, stock raising, muskrat breeding, and vegetable and melon growing. Fisheries are located in the basin of the Aral Sea and on the rivers emptying into it. The chief economic centers are Aral’sk and Muinak, which attract many fishing kolkhozes and fisheries. Fish-salting factories are located in the Amu Darya delta, in the settlements of Avan (on Kokaral Island) and Bugun’ (on the eastern shore), and on the islands of Uialy and Uzynkair.
The Aral Sea was first explored and mapped by A. I. Butakov in 1848–49.
REFERENCESBerg, L. S. Aral’shoe more. St. Petersburg, 1908.
Nikol’skii.G. V. Ryby Aral’skogo moria. Moscow, 1940.
Blinov, L. K. Gidrokhimiia Aral’skogo moria. Moscow, 1957.
Lymarev, V. I. Berega Aral’skogo moria—vnutrennego vodoema aridnoi zony. Leningrad, 1967.
V. I. LYMAREV