During the s, the Amu Darya and Syr Darya were increasingly diverted to contribute to more irrigation schemes to support cotton and rice farming, decreasing the area of the sea to slightly less than 60, km2 by FAO, Water withdrawal in the Aral Sea basin increased from about 90 km3 in to over km3 by the end of the decade, peaking in at km3 FAO, This further decreased surface area and volume and prevented runoff from the rivers to reach the Aral Sea from to Bortnik, With the division of the Aral Sea, the NAS reduced to half its area in by the early s from 6, km2 to a range of 2, to 3, km2 Bortnik, To prevent the western portion of the NAS from drying up and to increase water levels, a series of dams was constructed on the southeast coast of the NAS throughout the decade.
The dams did not last for long, as storms repeatedly destroyed them; the breach of a dam in Breckle and Geldyeva, led to a significant decrease in volume of the NAS with volume dropping to As Figure 2c shows, by the island in the northern part of the SAS joined the main land mass and a significant portion of the eastern SAS retreated, leaving behind the beginnings of a salt desert, referred to as the Aral-kum Low et al.
In the s, the Aral-kum continued to grow in size with the construction of a more stable and permanent dam that once again prevented Syr Darya outflows from reaching the SAS. The dam caused the NAS to fill up more quickly than expected, peaking in volume in Gaybullaev et al. This allowed for water to start slowly flowing back to the SAS World Bank, by way of a small intermittent river that flows primarily during the spring or early summer, when runoff from the Syr Darya to the SAS is greatest Micklin, The dam stabilised water levels of the NAS allowing for the fishing industry to begin its return World Bank, , but the minimal flow of water to the SAS was not enough.
By , the SAS had split into several bodies of water with two prominent lobes that were barely connected: an eastern lobe and a western lobe Figure 2d.
The total surface area of water of the SAS declined almost 50 per cent from to Figure 3. At present, seasonal fluctuations, variations in wet and dry years and annual fluctuations in the flow of the Amu Darya NASA, dictate water levels of the two lobes of the SAS as demonstrated by the satellite image time series in Figure 4. Figure 4 shows how much the eastern lobe of the SAS can fluctuate, including nearly disappearing in but rebounding to more than 10, km2 by Figure 3.
The surface area of the NAS remained relatively stable and some fluctuations in the Syr Darya delta are visible Figure 3.
Gaybullaev et al. Figure 3: Changes in total surface area of the Aral Sea for select years from to The changes in the area and volume of the Aral Sea have a serious impact on the environment, livelihoods and the economies of local populations in Central Asia. Some of these jobs, and fish catch, have been reclaimed due to the stabilisation of water levels in the NAS in the past decade and the replenishment of surrounding lakes.
Fishery output in the late s reached an estimated range of 2, to 3, t of fish, as compared to only 52 t caught in World Bank, The diversion itself has proved relatively successful economically, as irrigated lands, which cover only 10 per cent of all agricultural land in Uzbekistan, account for more than 95 per cent of gross agricultural products Botman, However, any and all benefits have come at a cost to local populations and the environment.
The Aral-kum is nearly 60, km2 of sandy, salty soil, most of which is contaminated with fertilisers remnant from the agricultural lands, that is fuel for dust storms Low et al. The surface area of salty soils and bare areas surrounding the Aral Sea, the surface types that generate the greatest potential for dust storms, increased to 54 per cent in from 40 per cent in Low et al.
Its increase in size has also contributed to a more arid local climate with hotter summers and colder winters Gaybullaev et al. Spivak et al. The salt-dust clouds can be up to km long and finer particles can travel up to 1, km away Semenov, The densely populated areas south of the Aral Sea in the Amu Darya delta are most vulnerable to these storms because of their location downwind from the Aral-kum source area Low et al.
These dust storms have negative implications for agricultural and pastoral land. As for local populations, increased respiratory and kidney disorders have been reported and the dust affects visibility for air and vehicle traffic UNEP et al. Further studies regarding implications of land cover change and increased salt and dust loads are needed Low et al. Additionally, more regional weather observations and models are needed to more effectively quantify impacts Low et al.
Widespread afforestation of the Aral-kum is needed to reduce ecological tension in the southern Aral region. Increased vegetation cover could help reduce the number dust storms Novitskiy, In the past decade or so, several international organisations have initiated afforestation projects in the Aral Sea region Simonett and Novikov, ; Vildanova, ; EC-IFAS, , creating forest plantations on the dried seabed of the Aral-kum to help stabilise soil Micklin, ; Botman, Local environmental health could be increased and maintained through the continued facilitation of afforestation projects Novitskiy, Involving local populations in afforestation could also make the projects more sustainable and less expensive to implement Botman, Increased agriculture has been accompanied by an increase in use of fertilizers and pesticides, which has compromised the quality of ground and surface water, contaminated seabed sediment and led to rising groundwater levels UNEP et al.
Granit et al. Water quality, especially for drinking, has also decreased because of increased salinity, bacterial contamination and the introduction of pesticides and heavy metals UNEP et al.
Low-energy and low-cost desalinisation techniques to increase quality of drinking water have yet to be developed or widely adopted in Uzbekistan Khaydarov and Khaydarov, Diversion of the Amu Darya and Syr Darya has not only resulted in lower water levels of the Aral Sea, but also in the disappearance of smaller lakes and deltas that these rivers once supported and of riparian habitats such as tugai forests and reed beds UNEP et al.
The Amu Darya delta supported about 2, lakes in the s, but the number had fallen to by Kreuzberg-Mukhina, Tugai forests and reed beds once covered more than , ha and now only about 10 per cent remains, having been replaced with irrigated cropland or having disappeared because of lack of water regeneration UNEP et al.
To restore the ecological situation of the surrounding deltas, numerous man-made lakes or reservoirs have been constructed.
As a result, wetland cover has increased and some migratory waterbirds have taken refuge Kreuzberg-Mukhina, Diversity remains low, but some species of waterbirds have expanded their breeding ranges along valleys of the Amu Darya and Syr Darya Kreuzberg-Mukhina, Transboundary co-operation is needed to address the future use of water resources between upstream Tajikistan and Kyrgyzstan and downstream countries Kazakhstan, Turkmenistan and Uzbekistan in the Aral Sea basin Eshchanov et al.
Attempts for transboundary co-operation for water and land management within the basin dates back to the early s when the Aral Sea first showed signs of decline FAO, A deeper integration of the critical issues at hand into institutional frameworks is needed to encourage co-operation Granit et al.
A lack of regional coordination to implement restoration effectively and awareness projects has been cited as the reason some attempts at cooperation have proved unsuccessful Sojamo, ; UNDP, Several committees, organisations and institutions have been created and third-party donors have been engaged to cope with the consequences of the loss of the Aral Sea.
Most recently, the High-Level International Conference on Water Cooperation held in Tajikistan addressed implementation of policies and highlighted the outcome of a multi-agency project that included a tangible set of analytical policy tools related to the water, agriculture and energy sectors adopted by all participating member countries FAO, Historically, countries across the globe have leaned toward co-operation in response to transboundary water competition UNDP, ; Mirumachi and Allan, Competition for water in the Aral Sea basin has led to the desiccation of the Aral Sea and a multitude of negative consequences for people, economies and the environment.
The ecosystems and livelihoods supported by the Aral Sea may never be what they were five decades ago, but they have a chance for revitalization Walters, with proper attention to water resource management, ecosystem health, human and energy needs and political will EC-IFAS, ; Granit et al.
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Fact Sheet — Nuclear Arsenals of the U. The Crisis in Mali. Protecting Yourself from Disinformation in Stay up to date! The salty dust blew off the lakebed and settled onto fields, degrading the soil.
Croplands had to be flushed with larger and larger volumes of river water. The loss of the moderating influence of such a large body of water made winters colder and summers hotter and drier.
In a last-ditch effort to save some of the lake, Kazakhstan built a dam between the northern and southern parts of the Aral Sea. The Kok-Aral dike and dam, finished in , separates the two water bodies and prevents flow out of the North Aral into the lower-elevation South Aral. The dam has led fisheries in the North Aral to rebound, even as it has limited flow into the South Aral. Between and , water levels in the North Aral rebounded significantly and very small increases are visible throughout the rest of the time period.
The differences in water color are due to changes in sediments and water depth.
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