Aral Sea desiccation: Environmental and economic impact

Bilal Afridi

Aral Sea is located in Central Asia between Uzbekistan and Kazakhstan, which serves as natural boundary of the two countries. It was the fourth largest inland lake in the world till 1960s. The major sour of filling the reservoir of the sea were two major rivers, Syr Darya and Amu Dasrya. Water from melting snow and glaciers on the southern Pamir Mountain in Tajikistan and the Tien Shan Mountain that border Kirgizstan and China are the contributory sources of water supply to these rivers.

The human induced degradation of environment in the shape of diverting water flow of Amu Darya and Syr Darya through irrigation projects for cotton plantations has led to enormous depletion of water level in Aral Sea reservoir, shrinking of its surface area and abnormally increased water salinity density. Aral Sea covers now 10 percent of its former surface area. It holds less than 10 percent volume of its former water storage and it receives 10 times less water from the two rivers it used to be six decades ago.

In 1960s, government of former Soviet Union had decided to divert bulk of the water flow from Amu Darya and Syr Darya for irrigating the arid regions surrounding the Aral Sea for mainly growing cotton crop. The implementation of lopsided programme of agriculture development deprived Aral Sea from its two major sources of water inflow, which led to arriving less water into the sea. Not only was all water inflow diverted into canals at the expense of Aral Sea supply but the soaking up of desert areas by way of flood irrigation method resulted in colossal waste of precious water resources between 25 to 75 percent.

The water level in the Aral Sea started lowering drastically from 1960s and onwards as in normal weather condition rainfall provides one fifth water supply to its reservoirs and the same amount then gradually evaporates. Hence bulk of water supply was delivered by Amu Darya and Syr Darya. The diversion of water flow of these rivers is the origin of imbalance that caused desiccation of the sea over the past four decades. As the flow of water from rivers substantially decreased and the supply from rainfall was evaporating, small lakes appeared in the Aral Sea, which contained high density of salinity, confronting all types of fish and other creatures with survival threat. Even the reintroduced varieties of fish in 1990s could not survive. The re-watering of drying lakes did not help reduce the salinity level that has increased over the years. In 1998, water level dropped by 20 meters with a total volume of 210 cubic meters as compared to 1,063 cubic meters in 1960s.

The Aral Sea region had a wide variety of flora and fauna with 38 species of fish and a number of species of rare animals that inhabited the sea basin. The number of Saigas had reached one million and the floristic composition comprised 638 species of higher plants. The sea played an important role in the development of the region’s economy. Aral Sea was among the richest fishing ground in the world with annual catch of fish 30-35 thousand tonnes. More than 80 percent of inhabitants of the sea coast were engaged in production, processing and transportation of fish and fish products. With desiccation of Aral Sea, the fishing industry has declined and 40,000 t0 60,000 people have lost their jobs. Fertile lands of the delta of Amu Darya and Syr Darya and lush green pastoral landscape had provided employment to more than 100,000 people in the spheres of livestock, poultry farming and growing different crops.

Aral Sea also served as climate adjusting reservoir by mitigating the impact of acute weather fluctuations throughout the region, which had favourable effect on the life of people, agriculture production and maintaining ecological balance. The glaciers shrinkage on the surrounding mountains is already occurring to reduced runoff and the region could experience greater climate change impact. As a consequence of desiccation of Aral the Sea the unprecedented environmental change is felt not only in the Central Asia but other regions of the world as well. On the back part of the Aral Sea, a new salt desert with an area of 5.5 million hectare has appeared. Every year for 90 days dust storm rages over the salt desert that spreads 100 million tonnes of dust and poisonous salt particle into the atmosphere over thousands of kilometers each year. The threatening impact of Aral Sea catastrophes is now witnessed all over the world today. According to international experts, poisonous salt from the Aral Sea region are found on the coast of Antarctica, on the Glaciers of Greenland, in the forests of Norway and many other parts of the globe.

The cotton growing culture and excessive use of insecticides and pesticides through Ariel spray has led to toxic pollution in Central Asia. The contaminated water and bad air quality has increased the rate diseases such as anemia, tuberculosis, respiratory infections, allergies, kidney diseases and cancer.

Realising the gravity of environmental degradation caused by Aral Sea desiccation, the government of Uzbekistan initiated the establishment of special fund for the Aral Sea and its Zone under the auspices of United Nations during the Un General Assembly Sustainable Development Summit. Establishment of fund is aimed to provide finances for the protection of health, preservation of gene pool of population and implementing programmes of socio economic uplift. The fund will also cater for the restoration of ecological balance by taking sustained measures to combat desertification and ensure judicious use of water resources, especially in the trans-boundary waterways. Moreover, financial resources shall be made available for restoration of biodiversity of animals and plants life, besides preservation of universal flora and fauna, which is at the verge of extinction.

Diversion of water sources has substantially reduced the volume of water in the reservoir of Aral Sea. It has broken it into smaller seas, leaving behind a vast desert and created numerous environmental, economic and social problems. Although the water level of Aral Sea may never return to pre 1960s level, yet the trans-boundary cooperation for the water conservation, using technology of drip irrigation instead of flood irrigation and crops substitution by switching over to olive plantation and Jojoba can reduce the magnitude of environmental impact over the region and beyond.

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