The tragedy of the Aral sea

the aral sea tragedyAbout the Aral Sea region

The Aral fleet used to furrow the sea and river ports from Termez to Aralsk. People used to feed wild pheasants in their hen-coops. Couples of tame swans spend winters on numerous lakes of the Aral Se region, wite gulls accompanied white steamboats in the sea. Beautiful goitered gazelles lived in the Kyzylkums, swift-footed saigas galloped across the Usturt.

But behind this placatory scenery indistinctly appeared the decline of a civilization when the Aral Sea began suffering of the human intervention. The sea has been decreasing since 1950-s influencing on the climate. Winters become more and more severe, summers – hotter and more arid. From the naked bottom of the sea called Aralkum the salty storms started to rage brining tons of poisoned dust to the green kands of the Central Asia. The first victims to suffer from the Aral masn-cuased disaster were not only the beautiful flora but the valuable fauna. Sturgeons are extinct, musk-rat and nutria farms are closed, most birds are registered in the Red Book.

Urga village, Uchsay and Muynak sea port have need erased from the geographic map. People started to move away. Population of Muynak region almost decreased almost twice.

Newborns pushed away the mothers’ breast rejecting improper milk of their mothers. Children and maternal death left beyond all conceivable norms of survival.

High unemployment in the region urged to create new jobs. With this aim several textile enterprises have been launched, foreign direct investments were attracted for constructing the Kyngrad soda plant and developing oil and gas fields in Usturt and Aralkum.

During the last several years almost all urban and rural healthcare facilities were provided with modern equipment and medical supplies. New colleges and academic lyceums are being lunched in various settlements of the region.

All across the world human kindness and mercy support the people facing ecological and social disasters caused. The situation in Aral us aggravated by реу fact that the gene pool of a whole nation of the Aral Sea region is disappearing.

Water Balance Changes

As in the past, the cause of the modern recession of the Aral is a marked diminution of inflow from the Syr Dar'ya and Amu Dar'ya, the sea's sole sources of surface water inflow, that has increasingly shifted the water balance toward the negative side. The trend of river discharge has been steadily downward since 1960.

A shrinking body of water is dominantly a negative feedback mechanism, that is, one that resists change and promotes stability. Evaporative losses significantly diminish as area decreases, pushing the water balance system toward equilibrium. Hence, in the future, assuming some level of surface- and ground-water inflow, the Aral should stabilize. However, this is not likely to occur for decades. The primary determinant of level change, the difference between inflow and net evaporation, is currently large and negative. It will only decrease slowly as the sea shrinks to a much smaller size.

The causes of reduced inflow since 1960 are both climatic and anthropogenic. A series of dry years in the 1970s, particularly 1974-75, lowered discharge from the zones of flow formation of the Amu Dar'ya and Syr Dar'ya around 30 km3 per year (27%) compared to the average during the preceding 45 years (8; 12, p. 227). The 1982 to 1986 period has also suffered low flows (12-14). Nevertheless, the most important factor reducing river flow has been large consumptive withdrawals (that is, water withdrawn from rivers that is not returned to them), overwhelmingly for irrigation. Average annual river flow in the zones of formation of these rivers (high mountains to the southeast of the Aral Sea) averaged 111 km3 from 1926 to 1970 (12) . Under "natural" conditions only about half of this would reach the Aral because of losses to evaporation, transpiration, and filtration as these rivers cross the deserts and flow through their deltas (12).

Irrigation has been practiced in the lower reaches of the Amu Dar'ya and Syr Dar'ya for several millennia (4). In 1900 more than 3 million hectares were under irrigation in the Aral Sea basin, growing to 5 million by 1960 when consumptive withdrawals for it reached an estimated 40 km3 (1, 15). However, irrigation withdrawals before the 1960s did not measurably reduce inflow to the Aral. These artificial losses were compensated by correspondingly large reductions of natural evaporation, transpiration, and filtration, particularly in the deltas of the Syr Dar'ya and Amu Dar'ya where truncated spring floods diminished floodplain inundation, the area of deltaic lakes, and the expanse of phreatophytes (12, 15, 16). Also, the installation of drainage networks increased irrigation return flows to these rivers.

By 1980, the irrigated area in the Aral Sea basin had grown to nearly 6.5 million hectares (17; 18, pp. 226-230). Withdrawals from the Amu Dar'ya and Syr Dar'ya for all purposes were 132 km3 with consumptive use, including evaporation from reservoirs, of 85 km3 (18, pp. 212-215). Irrigation accounted for 120 km3 of withdrawals (91%) and for 80 km3 of consumptive use (94%). Extrapolation, from data on area and rates of growth of irrigation for administrative units in the Aral Sea basin for the period 1980 to 1984 and 1980 to 1986, indicates that in 1987 about 7.6 million hectares were irrigated (17). Between 1980 and 1987, there was a major improvement in irrigation efficiency in the Aral Sea basin which lowered average withdrawals from 18,500 to 13,700 m3/ha (19). Thus a 17% larger area was irrigated with considerably less water (104 km3). Information on consumptive use in 1987 is not available but it probably remained near the 1980 figure because of the efficiency gains (that is, a higher percentage of withdrawn water was used by crops and a lower percentage was return flows).

Factors that compensated the earlier growth of consumptive withdrawals reached their limits in the 1960s (2, 12, 15, 16). Hence, as irrigation expanded during the past three decades, the increase in water use has not been balanced by commensurate reductions in natural losses. Furthermore, the irrigation of huge new areas such as the Golodnaya (Hungary) Steppe along the Syr Dar'ya consumed huge volumes of water to fill soil pore spaces (20), newly created giant reservoirs required filling and heightened evaporative losses, increased flushing of soils to counteract secondary salinization raised water use, and new irrigation systems discharged their drainage water into the desert or large hollows where it evaporated.

The Karakum Canal has been the single most important factor contributing to the diminution of inflow to the Aral in recent decades. The largest and longest irrigation canal in the Soviet Union, it stretches 1300 km westward from the Amu Dar'ya into the Kara-Kum Desert. Between 1956 and 1986, 225 km3 were diverted into it as annual withdrawals rose from less than 1 km3 to more than 14 km3 (21). All of the water sent along the Karakum Canal is lost to the Aral.

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