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41.
Constructing Water Shortages on a Huge River: The Case of Shanghai   总被引:1,自引:0,他引:1       下载免费PDF全文
Shanghai is located on the world's third largest river (by volume). Yet it faces the risk of shortages of drinking water. Many decisions and environmental characteristics have contributed to this threat. First, Shanghai has become dependent on water brought into the municipality by rivers. Second, it has become increasingly reliant on water from the Changjiang (Yangzi River), principally in order to control the levels of pollution in the water that enters its treatment plants. Third, for reasons associated with inter‐provincial administrative arrangements, the city's water intakes are located within the municipality, within the estuary zone and subject to tidal intrusions of salt water. Fourth, at high tide and when the Changjiang's discharge is low, salt intrudes far into the estuary, beyond the current water intakes. If sea levels rise, these intrusions will become more pronounced. Fifth, large‐scale central government infrastructure projects (such as dams and the South‐North Transfer) are altering the hydrological characteristics of the river. Such projects raise the probability of salt water intrusions into the water intake zone. The Shanghai and central governments have thus made a series of decisions that, taken together, have led the municipality to rely on a source of drinking water that is increasingly unreliable and subject to the risk of shortages due to salt water intrusions. Why these decisions have been made – independently – is an important problem for those who would understand the provision of water for cities and the practical efficacy of Chinese governance systems.  相似文献   
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During 1993, the London-Bahrain Archaeological Expedition conducted a fourth season of excavations at the early second millennium settlement of Saar, Bahrain. A lower level of the temple was cleared, and a range of buildings to its north-west discovered. A new street was found opposite the temple entrance, and several of the buildings along the main street were further investigated. Further environmental research included a new programme of micromorphology and the start of research into the fish remains.  相似文献   
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