Introduction to Aral Sea

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INTRODUCTION

The Aral Sea (Kazakh: Aral Teizi; Uzbek: OrolDengizi;

Russian: Aral'skoye More; Tajik: Bahri Aral; Persian:

Daryocha-i Khorazm) is a saline endorheic basin in Central Asia; it lies

between Kazakhstan (Aktobe and Kyzylorda provinces) in the north and

Karakalpakstan, an autonomous region of Uzbekistan, in the south. The name roughly

translates as "Sea of Islands", referring to more than 1,500 islands that once dotted its

waters.

Once among the four largest lakes of the world with an area of 68,000

square kilometres (26,000 sq mi), 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 it had declined to 10% of its original size, splitting into three lakesthe North

Aral Sea and the eastern and western basins of the once far larger South Aral Sea. 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. The maximum depth of the

North Aral Sea is 42 metres (138 ft) (as of 2008).

The region's once prosperous fishing industry has been virtually destroyed,bringing unemployment and economic hardship. The Aral Sea region is also heavily

polluted, with consequent serious public health problems. The retreat of the sea has

reportedly also caused local climate change, with summers becoming hotter and drier,

and winters colder and longer.

There is now an ongoing effort in Kazakhstan to save and replenish the

North Aral Sea. As part of this effort, a dam project was completed in 2005; in 2008,

the water level in this lake had risen by 12 metres (39 ft) from its lowest level in

2003. Salinity has dropped, and fish are again found in sufficient numbers for some

fishing to be viable. However, the outlook for the remnants of the South Aral Sea

remains bleak. It has been called "one of the planet's worst environmental disasters".


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1. General Description of the Region

The Aral Sea is one of the largest inland saltwater bodies in the world. In

1960, with a surfacearea of more than 67,000 km2, the Aral Sea was the worlds

fourth largest inland water body. Thebrackish lake with a salinity averaging near 10

g/l (less than a third of salinity of the ocean) wasinhabited by mostly freshwater

species. The sea supported a major fishery and functioned as a keyregional

transportation route. The extensive deltas of the Syr Darya and Amu Darya sustained

diverseof flora and fauna. They also supported irrigated agriculture, animal

husbandry, hunting andtrapping, fishing, and harvesting of reeds, which served as

fodder for livestock as well as buildingmaterials.The Aral Seas drainage basin

encompasses a total area of 1,549,000 sq. km, of which nearly590,000 sq. km are

arable land. The Aral Sea is situated in the center of the Central Asian great deserts

(Kara-Kum, Kyzyl-Kum, and Betpakdala) at an altitude of 53 meter above the sea

level and functions as a gigantic evaporator. About 60 km3 of water evaporates

peryear from the sea and its rivers. The Aral Sea size and water balance are

fundamentally determinedby river inflow and evaporation from its surface. Over the

past four decades, this water body hasrapidly and steadily shrunk and salinized ascountries inthe Aral Sea Basin have increasingly taken inflow from its two influents,

the Syr Darya and AmuDarya, for expansion of irrigation.

Amu Darya is the largest river in the region. The rivers main catchment

area is in Tajikistan, fromwhere it flows along the border between Afghanistan and

Uzbekistan, crosses Turkmenistan, flowsback into Uzbekistan and finally in the

territory of Uzbekistan the river flows into the Aral Sea.

In terms of silt content, the Amu Darya clearly ranks first in Central Asia

and one of the first inthe world. The Syr Darya River ranks second in terms of water

flow, even though it is actually thelongest river in Central Asia. Its sources are in the

Central Tian Shan Mountains. The river is at itsfullest in spring and summer, starting

in April and reaching its peak in June. Its main catchmentarea is in Kyrgyzstan, from


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where the river crosses Uzbekistan and Tajikistan and flows into theAral Sea in

Kazakhstan.Seven countries share the Aral Sea Basin: Afghanistan, Kazakhstan,

Kyrgyz Republic, Tajikistan,Turkmenistan, Uzbekistan and Iran. Up to 25.1% of the

entire flow in the Aral Sea basin is formed inKyrgyzstan, 43.4% in Tajikistan, 9.6%

in Uzbekistan, 2.1% in Kazakhstan, 1.2% in Turkmenistan,and 18.6% in Afghanistan

and Iran (Diagnostic Analysis, 2002). There is a very small part of thebasin located

on the territory of Iran. Only Kazakhstan and Uzbekistan are riparian states on

theAral Sea, with each possessing an approximately equal length of shoreline. It

should be noted thatthe interests of Kyrgyzstan, Kazakhstan and Turkmenistan

relating to the use of water resourcesare not restricted only to the Aral Sea area.

Kazakhstans share of irrigated lands within the AralSea basin stands at just 35%,

while the share of Kyrgyzstan does not exceed 40%. Different countriesin the Central

Asia region have very different populations, economic interests and activities,and

exercise different approaches to water management from a firmly market-oriented

approach in Kazakhstan to a full state property of water resources in Turkmenistan.


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2. Water Use in the Aral Sea Basin

Water usage, primarily for potable and irrigation, started more than 6,000

years ago. In the 20thcentury, and especially since 1960, the intensity of water use

increased under the pressures ofthe rapid population growth, industrial development

and, most of all, irrigation. Between 1960and 1990 the water use increased almost 2

fold. Irrigation accounts for 90% of the regions waterwithdrawal.

The shrinking of the Aral Sea

Aral Sea from space, August1985

Aral Sea from space,1997 Aral Sea from space, August

2009

In the Syr Darya Basin, water needs of the four republics conflicting

economic priorities of individualcountries have led to clashes of interest over water

release schedules from the ToktogulReservoir. Kazakhstan and Uzbekistan have been

insisting on giving priority to irrigation, whileKyrgyzstan and partly Tajikistan prefer

using water for electric power generation. As a result,since 1993, the Toktogul

cascade of reservoirs has been applying schedules that make for a sharpincrease in

summer storage and water drawdown in winter to suit the needs of the Kyrgyz hydro-

power industry. Since 1994 the water regime in the Syr Darya basin has been the

main theme ingovernment talks. To meet Kyrgyz demands for increased supplies of

heat-producing energy andthe needs of Kazakhstan and Uzbekistan in the summer

season, in 1998 a decision was made todefine mutual obligations of these countries in

fuel and energy exchange. This approach, however,does not account for all the

environmental problems in the watershed because releases from theSyr Darya will be


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falling below minimum discharge levels that have been recorded in the lasthundred

years of observation. On the other hand, the irrigation and water supply concerns of

thedownstream countries will only be met if the three upstream states fully comply

with the terms ofsigned agreements on fuel and power supply and the purchases of

excess electricity. The slightestnon-compliance will undermine sustainable water

supply. Actual implementation has revealed thatconflicting power and irrigation

needs of the four states have hindered the fulfillment of agreedwater allocation terms

and necessitate further talks.

Up until 1992, the allocation of the Amu Darya waters among the four

Central Asian republics wasbased on the water development master plan for the Amu

Darya basin. The allocation plan was approvedby resolution 566 of the Science and

Technological Council of the USSR Water ManagementMinistry in 1987. The

resolution fixed the following allocation of surface waters (% of projectedflow in the

main stem of the Amu Darya): Kyrgyzstan, 0.6%; Tajikistan: 15.4%;

Turkmenistan,35.8%; Uzbekistan, 48.2%. The quota principle has survived till now,

with Turkmenistan and

Uzbekistan getting equal shares of the so-called adjusted run-off measured

at the Kerky hydrographicsection, including diversion to the Karakum Canal. This

provision was reiterated in thebilateral agreement signed by the heads of these two

states in Cherdzjev (Turkmenabad) in 1996.


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An important issue in discussing the water use in the Aral Sea Basin is its

efficiency that is inadequatefor all economic sectors, especially irrigation farming.

Statistics indicate that principal waterlosses occur in the on-farm delivery networks

and directly in the field. According to WUFMAS(SIC/IWMI, 2002), water losses in

these two cases may account for 37% of the total supply tofarm contours. On average,

about 21% of irrigation supply is wasted directly in the field. Sincemost losses occur

in the field and in deliveries among farms, water user associations, along withcharges,

may be an effective way of streamlining the use and conservationof water. The next

sectiondiscusses diverse effects of the desiccation of the Aral Sea.

3. Ecological, Economic, Health Consequences of Aral Sea Desiccation

The four basic problems in water and environmental management of the

basin were formulatedby the World Bank/Global Environmental Facility Aral Sea

Basin Program Project Document(Global Environmental Facility, 1998):

environmental degradation, with the increase in land andwater salinization; the

gradual drying up of the Aral Sea, with huge adverse socio-economic

andenvironmental effects; water management in the basin, with its built-in potential

threat to peacein the region; and instruments for interstate cooperation, with the

commitment of sovereign statesthe big challenge. Despite the fact that this list of


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regional issues was produced in 1998, the sameissues of concern remain very relevant

today.

Environmental degradation, with the increase in land and water salinization

Salt loads in drainage water from irrigated lands in one state and is fully or

partially returned to therivers and passed to downstream states. The salinization

occurred because of the salt mobilizationin subsoil triggered by irrigation and

drainage practices, salt pick-up in upper watersheds and inadequatedisposal of

drainage water. Increasing salinization of the land and rivers threatens

entireeconomies and millions of people throughout the basin and results in:

1. Erosion and sedimentation that in turn threatens the basin water regulationinfrastructure. As a result of the increasing soil erosion in upper watersheds due to

deforestation and overgrazing of mountain pastures, changes in performance of

the basin water regulation infrastructure take place that affects the water

allocation and distribution in the basin;

2. Soil contamination. On all irrigated land in Central Asia pesticides and fertilizerswere used to an amount that by far exceeded the norms of the former Soviet

Union (Water Related Vision, 2000);

3. Diminishing wetlands and biodiversity. Desiccation of the deltas has significantlydiminished the area of lakes, wetlands, and their associated reed communities;

and

4. Environmental problems in mountain areas where water flow originates,including preservation of glaciers and glacier feed of rivers; sustainability of

mountain forests; erosion ofmountain slopes, especially as conditioned by the

development of irrigation in alpine valleys.


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The gradual drying up of the Sea and its adverse socio-economic and

environmental effects

As a consequence of the drastically reduced water flow from the rivers into

the sea, the Aralseparated into two water bodies in the end of 1988 beginning of

1989 - a Small Aral Sea in the north and a Large Aral Sea in the south. The Syr Darya

flows into Small Aral Sea, and the Amu Darya into the Large Aral Sea. Between

1960 and January 2003, the level of the Small Aral fell by 13 meters and the Large

Aral by 23 meters. A channel (river) has intermittently connected the two lakes, with

the flow from the Small Sea to the Large. The area of both seas taken together

diminished by 75 % and the volume by 90%. Salinity in the small sea is estimated to

have doubledwhereas in the western part of the large sea it has increased by more

than 6 fold. The Two lakeshave evolved in different ways. Salinization increased

from 10 g/l to 40-50 g/l because of lack of fresh water inflow.

The Small Aral Sea, located in the North, receives run-off of theSyr Darya

River and began to overfill due to positive water balance. The surface area of this

lake issmall, and evaporation from its surface is less than inflows from the Syr Darya,

atmospheric precipitationand ground waters. As for the Large Aral Sea in the south,

its water balance is negative,and evaporation from its huge surface is still higher than

the small inputs of the Amu Darya River,atmospheric precipitation and ground waters


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(Aladin, Plotnikov, Potts, 1995). These differences inthe hydrological regimes of the

two new lakes have led to stabilization of the Small Aral Sea leveland the continued

desiccation and salinization of the Large Aral Sea.The mainly human-induced

desiccation of the Aral Sea has had severe negative impacts. Strikingecological,

social and economic problems have arisen in the Pre-Aral area, including:

1. Desertification. Greatly reduced river flows through the deltas, the virtualelimination ofspring floods in them, due to both the reduced river flow and

construction of upstream storagereservoirs, and declining ground water levels,

caused by the falling level of the AralSea, have led to spreading and intensifying

desertification.

2. Dust and salt winds. One of the results of the sea drying and the desertification isthatstrong winds blow sand, salt and dust from the dried bottom of the Aral Sea,

now largely abarren, salt covered desert with an area near 50,000 km2, onto

adjacent lands. Estimates ofthe total deflated material, which were made in the

late 1980s, ranged from 13 million toas high as 231 million metric tonnes/year

(Glazovskiy, 1990, p. 22). The salt and dust alsohave ill effects on wild and

domestic animals by directly harming them and by reducingtheir food supply

(Palvaniyazov, 1989).

3. Changes in the regional climate. Owing to the seas shrinkage, climate haschanged in aband up to 100 km wide along the former shoreline in Kazakhstan

and Uzbekistan (Micklin,1991, pp. 52-53; Glazovskiy, 1990, pp. 19-21).

Maritime conditions have been replacedby more continental and desertic regimes.

4. Health problems of the population. The population living in the ecologicaldisaster zonesuffers acute health problems (Micklin, 1992; Medicins sans

Frontieres, 2000). In an interviewmade by Manchester Guardian Weekly in

November 2003 (Brown, 2003) an aidworker who was one of the last to visit the

southern Aral region said: The people are ina terrible state, drinking out of

muddy ditches, which is all that remains of a once mightyriver. We had a plan to


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relocate the people but Uzbekistan refused to agree and threw usout. No one has

any idea what happened to the people we were trying to help.

Local health experts also consider airborne salt and dust as a factor

contributing to high levelsof respiratory illnesses and impairments, eye problems, and

possibly even throat and esophagealcancer in the near Aral region (Abdirov et. al,

1993; Tursunov, 1989). More recent field work bya British-led group indicates that

salt and dust blowing from the dried bottom (and likely from irrigatedfarmland in

regions adjacent to the Aral Sea) is laced with the heavy use of toxic chemicals(e. g.,

pesticides and defoliants for cotton) in irrigated agriculture, mainly during the Soviet

era.

However, the most serious health issues are directly related to thirdWorld

medical, health, nutritionand hygienic conditions and practices. Bacterial

contamination of drinking water is pervasiveand has led to very high rates of typhoid,

paratyphoid, viral hepatitis, and dysentery. Tuberculosisis prevalent as is anemia,

particularly in pregnant woman. Liver and kidney ailments are widespread;the latter

is probably closely related to the excessively high salt content of much of thedrinking

water. Medical care is very poor, diets lack variety, and adequate sewage systems arerare.

Health conditions in the Karakalpak Republic in Uzbekistan, with the possible

exception of placesin the formerly civil war-torn Tajikistan, are likely the worst in the

Aral Sea Basin. Surveys conductedin the mid to late 1980s showed the average infant

mortality rate at more than 70/1000 livebirths whereas several districts adjacent to the

former seashore ranged from 80 to over 100/1000live births (Micklin, 1992). These

rates are three to four times the national level in the formerUSSR and 7-10 times that

of the U. S. Although efforts have been made in the post-Soviet periodto improve

health conditions here, it is doubtful these rates have declined in any substantial way.


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The Pre-Aral area is characterized by a complex spatial structure of

ecosystems. These are influenced by the physical and geographical conditions of the

region, the consequences of its economic utilisation during many centuries, and the

active influence of modern anthropogenous processes. Pre-Aral ecosystems are

developing in extreme conditions of desert. The factors limiting biota development

were established by nature itself. The Pre-Aral area has suffered from

anthropogenous processes for a long time, both regionally and locally.Anthropogenous impacts have caused transformations of natural ecosystems which

finally led to dramatic changes and degradation.

The ecosystems of delta valleys have been transformed greatly by

agricultural land use for many centuries. Irrigated or cultivated fields, rice fields and

non-cultivated agricultural lands which are characterized by different stages of soil

and vegetation cover rehabilitation, are singled out. The following anthropogenic

factors that brought about changes in the ecosystems should be considered according

to their significance: pastures, land-use, agriculture, transport, city, rural, military

objects, hydrotechnical (artificial reservoirs, dams, canals, sewage accumulators), and

cattle-breeding.


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REFERENCES

Aladin N. V., Plotnikov I. S., Potts W. T. W. (1995).The Aral Sea desiccation and

possible waysof rehabilitating and conserving its Northern part, Int. J.Environmetrics6, 17-29.

Philip P. Micklin. Project SPECA, Almaty, Kazakhstan, email: [email protected] Michigan University, USA.

WEB ADRESSES

Anonim. 2010. Aral, the Drying Sea. http://unimaps.com/aral-sea/index.html.Accessed on May 30 2010.

http://www.worldlakes.org/lakedetails.asp?lakeid=9219

http://www.aralvision.unesco.kz/contents_r.htm

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Introduction to Aral Sea