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Effects of Shrinking Aral Sea
Disclaimer: Material given in this presentation is directly taken from various websites / sources
Location and Size of Aral SeaAral Sea BasinDesiccation ProcessCauses of DesiccationEffects of Aral Sea DisasterEfforts / Planned Projects to Solve the ProblemMeasures to Save Aral Sea (Way Forward)
Scheme of Presentation
Aral Sea
Kyzlorda
Aktobe
Krakalpakstan
Lies between Kazakhstan (Aktobe and Kyzlorda provinces) in the North and Krakalpakstan, in the South
Aral Sea
Aral Sea translates into "Sea of Islands", referring to more than 1,500 islands that once dotted its waters, Syr and Amu Darya are its sources of water
Amu Darya
Syr Darya
Aral Sea
Aral Sea
In 1960 Aral Sea was one of the four largest lakes in the world with an area of 68,000 sq km, Average depth 16.1 M and Maximum depth 68 M
Aral Sea BasinBasis for life in Aral Sea Basin area always was
agriculture and livestock farmingDependence of region on water storage and land
resources exists from times immemorialEcosystem of the region is very vulnerable to manmade
impacts because of arid conditions Extensive method of economic activity and significant
population upsurge prompted occurrence of numerous regional environmental, social and economic problems, including global scale catastrophe as Aral Sea tragedy
Aral Sea is recognized by world community to be one of the greatest catastrophes of the 20th century
Causes of Aral Sea Desiccation
Causes of Aral Sea DesiccationFrom late 1950s to 1990 large-scale programmes on land
development were implemented in the Aral Sea BasinBy 1960 water diverted from rivers that feed the Aral Sea
irrigated 11 million acres, most of it former desert, producing enough cotton to make the Soviet Union a net exporter of “white gold”
Karakum Canal; 1400 km through desert (Turkmenistan)From 1974 to 1986 almost no water reached the Aral Sea
from Syr Darya While the sea had been receiving about 50 cubic km of
water per year in 1965, by the early 1980s this had fallen to zero
Causes of Aral Sea DesiccationFor more than 30 years, about 90% water from the Amu
Darya and the Syr Darya diverted to irrigate millions of acres of land for cotton and rice production
Now these rivers irrigate 20 million acres landExcessive irrigation substantially decreased inflow to
Aral, and the Aral’s shoreline began to recede rapidlyMismanagement / wastage of waterSeepage because of unlined water channelsEvaporation due to very high temperature
Aral Sea Desiccation Process
Aral Sea 1853
Formerly one of the four largest lakes in the world with an area of 68,000 sq km, the Aral Sea has been steadily shrinking since the 1960s after the rivers that fed it were diverted by Soviet Union irrigation projects
By 2007, Aral Sea declined to 10% of its original size, splitting into four lakes – the North Aral Sea and the eastern and western basins of the once far larger South Aral Sea and one smaller lake between North and South Aral Sea
Aral Sea 1989
Vozrozdeniye Island
Aral Sea 2000
By 1990s, surface area of the Aral had shrunk by nearly half, and the volume was down by 75%
Aral Sea 2001
Aral Sea 2002
Water flow into the Aral Sea decreased and water-level lowered more than 21 m
Aral Sea 2003
Aral Sea 2004
Aral Sea 2005
Aral Sea 2006
Aral Sea 2007
Aral Sea 2008
Aral Sea 2009
By 2009, the south-eastern lake had disappeared and the south-western lake retreated to a thin strip at the extreme west of the former southern sea
Aral Sea 2010
Contaminated Aral dust storms have been reported as far away as the Arctic, fertile Fergana Valley and Pakistan
Effects of Desiccation of the Aral Sea
Effects on LandEffects on HealthEffects on Fishing IndustryHydrological EffectsEffects on ClimateEffects on Ecology
Effects of Aral Sea Desiccation
Effects on LandOver-irrigation and use of chemical fertilizers / pesticides
caused toxic salt buildup in many agricultural areasAs the water retreated, salty sea bed soil was exposedMore than 4 million hectares of lands turned into desertDeltas of Amu Darya and Syr Darya are worst hit regionsAridity of climate, natural supplies of salts in deposits of
alluvial plains, land erosion, salt-dust transfer from drying bottom of the Aral Sea accentuated the problem
Loss of vegetation
Effects on LandContamination of water and soil with industrial and
household wastes, pesticides etc Major part of the region has changed as a consequence
of manmade activity (deforestation, water deficit, irrigation, steppes ploughing)
Decrease of number of flora and fauna speciesCollapse of Tugai Forests in Aral near-shore zonesDust storms have blown up to 75,000 tons of exposed
soil annually, dispersing its salt particles and pesticide residues
Effects on Population Health Population health was changed for the worse because of
environmental problems including water contamination
and air pollution, lack of potable water, poor sanitation
More than 5 million people living in Amu Darya and Syr
Darya deltas affected directly
Airborne salt and dust is linked to a rising incidence of
respiratory illnesses and may be a cause of throat and
esophageal cancer
Cancers have increased by 30 times; arthritis by 60 times; chronic bronchitis by 30 times
Effects on Population Health Poor quality drinking water, frequently obtained from
rivers and irrigation canals, has a high salt content and
contains pesticides, defoliants, and fertilizers
Drinking water contaminated with viral and bacterial
pathogens is responsible for high rates of typhoid,
paratyphoid, viral hepatitis, and dysentery
Maternal and infant mortality rate in epicentre of the
disaster zone is one of the highest in CARs
Decrease of life expectancy, high rate of tuberculosis,
anemia, cancer, asthma, dysfunction of thyroid gland etc
Vozrozhdeniye Island In 1952, the former Soviet Defence Force started to
conduct experiments with biological agents and aerosols for a range of military purposes
Due to its remoteness, Vozrozhdeniye Island in the Aral Sea was selected for open-air testing.
World's largest biological-warfare testing ground Experiments conducted on horses, donkeys, sheep,
monkeys and on laboratory animals, such as white mice, guinea pigs and hamsters
Vozrozhdeniye Island
Vozrozhdeniye Island
Lab Complex Vozrozhdeniye Island
Vozrozhdeniye IslandSparsely populated deserts and semi-deserts
surrounding the Aral Sea, the island’s climatic
conditions and the isolation from the neighbouring
mainland reduced propagation and transmission risks
Agents tested at the Island included anthrax, tularemia,
brucellosis, plague, typhus, Q fever, smallpox,
botulinum toxin
Vozrozhdeniye Island In 1992, the Russian Government declared the closure of
facilityStructures were dismantled, and the island was
decontaminated and transferred to Kazakh control In August 1995, specialists of the US Department of
Defense confirmed this after site visitsBecause of the tests, environmental specialists have for
many years been concerned about the contamination of the island by pathogenic micro-organisms, some of them resistant to standard antibiotics
Anthrax spores can survive in soil for decades, creating a lasting source of contamination
Vozrozhdeniye IslandDesiccation of Aral Sea resulted in the increase of
Vozrozhdeniye Island’s surface Its initial surface of 200 km sq expanded to 2000 km sq
in 1990Vozrozhdeniye Island connected to the mainland which
undermine safety aspectsContamination poses continuous and increasing threat
to the environment and the health of the population around the Aral Sea
Vozrozhdeniye Island In 2001, the Kazakh government announced with great
fanfare that the Aral Sea region contains major oil deposits
Effects on Fishing Industry Increasing salinity became intolerable for various kinds of
fish beginning in the 1970s, and some species unique to the Aral Sea are now extinct
As the Aral shrank, its salinity increased, and by 1977 the formerly large fish catch had declined by over 75%
By the early 1980s, commercially useful fish had been eliminated, shutting down an industry that had employed 60,000
Region's once prosperous fishing industry has been virtually destroyed, bringing unemployment and economic hardship
Ships lie abandoned on salt-encrusted sea beds, and fishing villages are now up to 50 km from water
Abandoned Aral Fish Harbour
Abandoned Ships / Fishing Trawlers
Abandoned Ships / Fishing Trawlers
Effects on ClimateLocal climate has shifted
Aral Sea used to absorb heat during summers, maintain humidity in the region and during winters large water body helped maintaining temperature to a reasonable level
Desert land has spread; wetlands have dried up; and sandstorms, stirring up pesticide-laden dust, are more common
Summers are hotter and dryer and winters colder
Hydrological EffectsAral Lake's salt concentration increased from 10% to
more than 23%Ground-water level dropped resulting into drying wells
and springs and degrading natural plant communities, pastures, and hayfields
Deterioration of EcosystemDiminished flow of the Syr Dar'ya and Amu Dar'ya has
had devastating effects on rivers' deltas Prior to 1960, these oases surrounded by desert not only
possessed great ecological value because of the richness of their flora and fauna but provided a natural feed base for livestock, spawning grounds for commercial fish, reeds harvested for industry, and opportunities for commercial hunting and trapping
Between 1960 and 1974, the area of natural lakes in the Syr Dar'ya Delta decreased
11 of the 25 largest lakes disappeared and 4 of the remainder significantly receded
Effects on Natural HabitatLivestock raising suffered considerable damage
because of a decline in yields and a reduction of suitable areas
Between 1960 and 1980 the area of hayfields and pastures decreased by 81% and yields fell by more than 50%
At one time 173 animal species lived around the Aral, mainly in the deltas; 38 have survived
Commercial hunting and trapping have largely disappeared
Harvest of muskrat skins in the Amu Dar'ya Delta has fallen to 2,500 per year from 650,000 in 1960
Projects to Save Aral Sea
Soviet planners prepared a plan to transfer waters from
Siberia's Ob-Irtysh and the Volga Rivers
Canals would drain water from each of these rivers and
move it south to the Aral Sea
Ob River pours 385 cubic km of water into the Arctic
Ocean, the Volga River pours 240 cubic km of water per
year into the Caspian Sea
This is about 10% above normal and has gone on for
years
Projects to Save Aral Sea
Plan to Transfer Water from Ob-Irtyshand Volga Rivers
Mikhail Gorbachev's glasnost put an end to this scheme, as the Soviet populace became aware of ecological disasters, and began to have the freedom to petition and protestIn 1988, the Soviet Central Committee decreed that cotton growing was to be reduced, so that the Aral Sea could receive water in gradually increasing amounts of water
There was some reduction in water diversion as a resultDissolution of the Soviet Union at the end of 1991 ended
central authority and Aral Crisis was in the hands of the five Central Asian nations
Projects to Save Aral Sea
Projects to Save Aral SeaThey signed an agreement in 1992 pledging efforts
toward Aral rehabilitation, but little action has been takenEfforts to address the crisis have focused on preventing
further shrinkage of the Aral Sea International Fund to Save Aral SeaNumerous Studies
Another meeting, in January 1994, resulted in offers to reduce water consumption, and promises of money for an Aral Fund
Projects to Save Aral SeaFull restoration of entire Aral Sea would require a large
scale regional changes, such as a shift away from
agriculture and huge amount of funds which under the
prevalent environment may be a difficult proposition
An effort to save and replenish the North Aral Sea was
made by Kazakhstan
As part of this effort, a dam project was completed in
2005; and by 2008, the water level in this lake had risen
by 24 m from its lowest level in 2007
Measures to Save Aral Sea
Measures to Save Aral SeaDamage is so severe that it is practically irreversible
Sea can be stabilized with improvements in the efficiency
of irrigation, but would remain incapable of supporting
most fauna, and the current problems of pollution and
lost habitat is likely to go unaddressed
Substantial but feasible irrigation improvements, and
some reduction in cropland, would allow partial
restoration of the sea, though it would still be incapable
of supporting its former fisheries
Measures to Save Aral SeaUrbanization, combined with large revenues from oil and
gas projects, might facilitate shift from existing
irrigation practicesWasteful and inefficient Irrigation System developed
during the Soviet era needs to be modernizedGenetically engineered crops that need less water
Israeli engineers experimenting on an Uzbek cotton farm
claimed they had increased yield by 40% while reducing
water consumption by two thirds
Thank You
Amu Darya
Syr Darya
North Aral Sea