Vital Caspian Graphics - Challenges Beyond Caviar

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than sodium sulphate. In the 1940s and 1950s the industry moved from the exploitation of open-air reserves to underground resources trapped below several metres of sediment. The story came to a happy end. Well almost. After destruction of the dam, the water flowed in at a rate of 700 cubic metres a second and it only took a few months to refill the lagoon (during which time the level of the Caspian happened to go on rising). The crust of salt dissolved and the pink flamingos, ducks and pelicans returned. The Kara Bogaz almost completely recovered its ecological balance. Only the chemical industry, which de- pended on a system of management that had dis- appeared, did not survive this unusual episode in the life of the lagoon.

cal industry. Exploitation started at the beginning of the 20th century along fairly traditional lines and only switched to more industrial techniques in the early 1930s. Annual production capacity is enormous: 400,000 tonnes of sodium sulphate (used in the glass industry, feed for livestock and detergents), 100,000 tonnes of bischofite (a defoli- ant used for machine-harvesting of cotton), 35,000 tonnes of epsomite (used in paper-making, tanning – to treat leather – and the textile industry), 10,000 tonnes of glauberite (pharmaceutical industry) and 20,000 tonnes of sodium chloride (cooking salt). From the 1930s onwards the drop in the level of the Caspian and the change in the chemical conditions led to a deterioration in the quality of the salt. As the brine thickened it accelerated precipitation of the salt as sodium chloride, a less valuable product

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