咸海的消失 英语PPT资料课件.ppt

The Aral Sea,Outline,Location,The Aral Sea is a saline basin in Central Asia and it lies between Kazakhstan in the north and Uzbekistan in the south.The name roughly translates as Sea of Islands, referring to more than 1,500 islands that once dotted its waters.,Early Days,Once among the four largest lakes of the world with an area of 68,000 square kilometers, The Aral Sea was especially prosperous in its fishing industry.,Shrinkage,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 lakes the 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 southwestern 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 meters.,Cause,1918, the Soviet government decided that the two rivers that fed the Aral Sea, the Amu Darya in the south and the Syr Darya in the northeast, would be diverted to irrigate the desert, in order to attempt to grow rice, melons, cereals, and cotton. Lenin(列宁) said that Irrigation will do more than anything else to revive the area and regenerate it, bury the past and make the transition to socialism more certain“.,This was part of the Soviet plan for cotton, or white gold, to become a major export. This did eventually end up becoming the case, and today Uzbekistan is one of the worlds largest exporters of cotton.,Actually, the disappearance of the lake was no surprise to the Soviets and they expected it to happen long before. As early as in 1964, Aleksandr Asarin at the Hydroproject Institute(水利工程学院) pointed out that the lake was doomed explaining, “It was part of the five-year plans, approved by the council of ministers and the Politburo（政治局）. Nobody on a lower level would dare to say a word contradicting those plans, even if it was the fate of the Aral Sea.,Effect,The ecosystem of the Aral Sea and the river deltas feeding into it has been nearly destroyed, not least because of the much higher salinity. The receding sea has left huge plains covered with salt and toxic chemicals the results of weapons testing, industrial projects, pesticides and fertilizer runoff which are picked up and carried away by the wind as toxic dust and spread to the surrounding area. The land around the Aral Sea is heavily polluted.,environment,the people living in the area are suffering from a lack of fresh water and health problems, including high rates of certain forms of cancer and lung diseases. Respiratory(呼吸的) illnesses including tuberculosis (肺结核) and cancer, digestive disorders, anaemia（贫血）, and infectious diseases are common ailments in the region. Liver, kidney and eye problems can also be attributed to the toxic dust storms. Health concerns associated with the region are a cause for an unusually high fatality rate amongst vulnerable parts of the population.,public health,And the people living in the area are suffering from a lack of fresh water and health problems, including high rates of certain forms of cancer and lung diseases. Respiratory(呼吸的) illnesses including tuberculosis (肺结核) and cancer, digestive disorders, anaemia（贫血）, and infectious diseases are common ailments in the region. Liver, kidney and eye problems can also be attributed to the toxic dust storms. Health concerns associated with the region are a cause for an unusually high fatality rate amongst vulnerable parts of the population.,The Aral Sea fishing industry, which in its heyday had employed some 40,000 and reportedly produced one-sixth of the Soviet Unions entire fish catch, has been decimated, and former fishing towns along the original shores have become ship graveyards. The town of Moynaq in Uzbekistan had a thriving harbor and fishing industry that employed approximately 30,000 people ; now it lies miles from the shore. Fishing boats lie scattered on the dry land that was once covered by water many have been there for 20 years. The only significant fishing company left in the area has its fish shipped from the Baltic Sea, thousands of kilometers away.,economy,Solution,Improving the quality of irrigation canals;Installing desalination plants;Charging farmers to use the water from the rivers;Using alternative cotton species that require less water;Using fewer chemicals on the cotton;Moving farming away from cotton;Installing dams to fill the Aral Sea;,