Due to the extensive agricultural activities devised by the Soviet government in the region, the former fourth-largest lake of the world is now the world's eighth largest lake. This has resulted in perhaps the world's most prominent man-made ecological disaster.
1. Geography/Facts about Sea
The Aral Sea is located in the Central Asian Republics of Uzbekistan and Kazakhstan, with the southern section located in the Autonomous Republic of Karapakalstan. Due to its location in the center of a vast mainland far from oceans, the Aral Sea maintains a continental climate. Temperatures in the region reach 40 degrees centigrade in the summer and in winters temperature falls down to -20 degrees centigrade with minimal precipitation. The main volume of surface waters is consisted of thaw water from high glaciers, feeding the two recently largest rivers of the region:
Amu Darya
Located in Eastern Central Asia. It is c.1,600 mi (2,580 km) long and flows generally northwest from sources in the snow-capped Pamirs along the border of Afghanistan and Tajikstan, Uzbekistan, and Turkmenistan through the Kara Kum desert in E Turkmenistan to a large delta on the Aral Sea in NW Uzbekistan. The waters of the river are used for irrigation in Turkmenistan and Uzbekistan.
Syr Darya
It is c.1,380 mi (2,220 km) long, used extensively for irrigation. It is formed in the Fergana Valley in Eastern Uzbekistan, by the confluence of the Naryn and Kara Darya rivers (which rise in the snowy Tian Shan) and flows west through northern Tajikistan, then northwest through E Uzbekistan and along the edge of the Kyzylkum desert to the northern end of the Aral Sea.
Countless lagoons and shallow and narrow straits between islands were the main characteristics of the Aral landscape. More than 1,100 islands had made the name of the sea: in Kazakh language the word "Aral" stands for "island". Vast lake systems of the deltas (about 300,000 sq. km.) played a great role in reproduction of fish sources and in fishery.
2. Regional Economy
Since before 1000 years B.C., settlers in the Uzbekistan territory used irrigation systems for agriculture. Before the Soviet domination, the region's economy was based on large-scale fisheries, livestock-breeding and agriculture. In 1970-1980s the fish catch from the Aral was 40,000 tons.
Under Khrushchev, however, there was a greater push towards agricultural and industrial production in the region. It was then that the massive agricultural activities that ultimately have led to the death of the sea began. During this period, the Aral region produced 1/4 of the natural gas extraction, 40% of rice and 90% of cotton in the former USSR. The Aral Sea Basin is rich with natural resources: iron ore, non-ferrous metals, oil and gas, large deposits of coal, copper, lead, tin, tungsten, molybdenum, fluorite, lithium, gold, silver, antimony, and mercury.
1. Diversion Projects Undertaken by Soviets
1. Agricultural Diversion
Under the Soviet empire, the amount of acreage under irrigation in the Aral region nearly tripled. This resulted in the diversion of almost 100% of the waters of the Syr and Amu Darya Rivers before they reached the Aral Sea.
Irrigation efficiencies in the region are said to be no better than 40 or 50 per cent - the rest is lost before it reaches the fields; the water soaks into unlined canals, or is evaporated. In other areas, standing pools of water mark the groundwater level, which has risen dramatically over the past 30 years, another result of poor drainage
2. Effects
http://news1.thls.bbc.co.uk/hi/english/special_report/1998/water_week/newsid_70000/70460.stm, "The Aral Sea Crisis"
http://ntserver.cis.lead.org/aral/toc.htm, "Aral Sea Case Study"
http://www.geology.sdsu.edu/facilities/carre/carre_study.html, "The Aral Sea Area Desertification Change-Detection Study"
Once fourth largest lake of our planet - the Aral Sea - has been drying up during four decades. By 1995 the Sea lost 3/4 of its water volume, surface area shrank by half, water level fell by 19 meters. The Sea runoff its shores by 100-150 km and exposed more than 33 sq. km. of its seabed, where more than 100 million tons of salty dust are being carried out faraway from the sea line annually. It is consisted of grains in form of aerosol with impurities of agricultural poisonous inputs, fertilizers, and other harmful industrial and household drains. Waters from rivers do not reach the Sea because they gradually disappear in desert sands.
The drying up of the Aral Sea is also negatively affecting the region's climate. Earlier, the Aral Sea acted as a climate regulator for the region: it softened cold Siberian winds in winters and acted as a conditioner lowering heat in summer months. The sea's shrinkage has resulted in drier and shorter summers, and in longer and colder winters. The growing season has been shortened to 170 days (while 200 is necessary for cotton production). Precipitation on shore in the Aral region has decreased by a factor of 10, the humidity of air has decreased by 10%, summer temperatures have increased and winter temperatures decreased by + 2-3 degrees centigrade. The productivity of pasture-grounds half its previous level.
The pollution effect is aggravated by the fact that the Aral Sea is situated on the "highway" where strong currents of air are blowing from the West to the East. This promotes carrying up of aerosols to higher layers of atmosphere and spreading of them around the Earth. That is why pesticides from the Aral region are found out in blood of penguins in the Antarctic Continent. The distinctive Aral dust is falling on glaciers of Greenland, on forests of Norway, and on fields of Belorussia, which are remote from Central Asia by thousands kilometers.
The other dangerous consequence of desiccation of the Aral Sea is a degradation of mountain glaciers of the Himalayas, the Pamirs, the Tien Shan and the Altais, which feed the Syrdarya and the Amudarya Rivers. An increase of toxic dust on the surfaces of glaciers and mineralization of precipitation are promoting melting of the glaciers. This is a dangerous process for an arid region because mountain glaciers of Central Asia are the only ancient reserves of fresh water and the main place for condensation of atmospheric moisture in the region. If the "cover" of sedimentation continues to accrue, the glaciers will not be condensers of moisture any more and there will be a decrease in drainage to the rivers.
In the region there were 500 species of birds, 200 species of mammals and 100 species of fishes lived in fresh, slightly saline or saline water. Insects and invertebrates were countless.
What affects nature, however, also affects humans. The process of environmental degradation in the Aral region has led to a socioeconomic crisis. As a result of the pollution and ensuing poverty, the region has highest rates of children mortality in the former Soviet Union (75 for 1,000 births) and high rates of maternal mortality (about 120 for 10,000 confinements). Diseases of destitution are widespread: infectious and parasitic ones, such as typhus, paratyphus, hepatitis, and also tuberculosis. In epicenter of the ecological disaster there are widely spread anemia, malfunction of thyroid gland, diseases of kidney and liver. Additionally, there are abnormally high levels of blood diseases, cancer, asthma, and heart disease, all of which can be linked to the ecological disaster.
Furthermore, in the Aral region there is a shortage of water. A rural inhabitant receives only 15 liters instead of the normal 125 liters, and an urban one receives 40 liters while in the country the average rate is 550 liters. In the crisis zone people fail to receive water sometimes for several days at a time.
It has also led to an economic disaster as the main industries of the region have all collapsed. Changes in salt content of the Aral Sea and loss of the biota have led to complete crash of fishery and processing industries and that resulted in unemployment of 60,000 people connected with sea jobs. In 1996 only 547 tons of fish were caught in the destroyed deltas of the Syrdarya and Amudarya rivers and 100 tons of this amount were plaices. A high content of poisonous pesticides is found in those fish that are caught.
1. Environmental/Economic
* Degeneration of the delta ecosystems
* Total collapse of the fishing industry (originally 44,000 t/a)
* Decrease of productivity of agricultural fields
2. Health
* Increase of serious diseases( e.g. cholera, typhus, gastritis, blood cancer)
* Increase of respiratory system diseases (asthma, bronchitis)
* Birth defects and high infant mortality
3. Climatic
* Mesoclimatic changes (increase of continentality)
* Increase of salt and dust storms
* Shortening of the vegetation period
1. Recovery Efforts
1. Brief Overview of Projects
Under Gorbachev, the Aral catastrophe was made public. The Aral Sea also helped to spur on the fall of the Soviet Union as a strong grassroots movement grew up around it, perhaps the strongest movement in all of the former Soviet Union. The sea has also attracted a multitude of international aid aimed at restoring the sea. Significant contributions have come from US AID, UNDP, the World Bank (WB is providing more than $240 million for seven different projects).
http://www.unops.org/5proin/5pi2001.html, "Project Information: Aral Sea"
One attempt they have made is to build a dike between the two lakes that have developed. The larger lake grows drier by the year and appears to be beyond saving, while the smaller, northern lake may be salvageable according to local and international experts. In 1997 the town of Aralsk built a dike 12 miles long and 85 feet wide between the two lakes. Protected from the larger, contaminated body, the smaller lake's shoreline began to stretch again toward the ships' cemetery. Birds reappeared, including gulls, swans, and pheasants. Danish scientists analyzed fresh sole from its waters and were amazed to find them clean enough to eat. The water went gone from a depth of 115 feet to 125 feet.
But solutions are complicated: while researchers are mindful of the need to minimize demands on the Aral, they must also work to preserve the irrigation-based economy of the region and try to balance the water demands of the various regions. Presently, there are conflicting water demands between the mountainous, upstream countries of Kyrgyzstan and Tajikistan, which provide 90 percent of the water resources in the CAR and which want to continue using water from the Amudarya and Syrdarya Rivers for energy production, and the downstream, lowland countries of Kazakstan, Turkmenistan, and Uzbekistan, which presently use 60 percent of the CAR's water resources for irrigation.
2. Future
Many feel that it is beyond hope. Due to protection efforts, however, the sea level has not shrunk as much as had been forecasted. Nonetheless, the problems will continue well into the future. One unforeseen problem that has received international attention lately is the possibility that a land bridge will emerge between the shore and an island in the middle of the sea upon which the Soviet government conducted biological and chemical tests. This means that humans and animals could have walking access to such toxic substances as anthrax
Saturday, September 25, 2010
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