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      Water of the 21st Century21世紀水資源

      來源:apple 編輯:apple 時間:2017-05-17

      Water of the 21st Century21世紀水資源
           Life on earth depends  on  water,and there is no substitute for it. The current assumption is that our basic needs for water-whether for drinking, agriculture, industry or the raising of fish--will always have to be met. Given that premise, there are two basic routes we can go. more equitable access to water or more drastic engineering solutions.
           Looking at the engineering solution first, a lot of my research concentrates on what happens to wetlands when you build dams in river basins, particularly in Africa. The ecology of such areas is almost entirely driven by the seasonal change of the river--the pulse of the water. And the fact is that if you build a dam, you generally wreck the downstream ecology. In the past, such problems have been hidden by a lack of information. But in the next century, governments will have no excuse for their blissful ignorance.JOOZONE.COM
           The engineers ability to control water flows has created new kinds of unpredictability too. 'Dams in Africa have meant fewer fish, less grazing and less floodplain agriculture--none of which were anticipated. And their average economic life is assumed to be thirty years. Dams don't exist for ever, but what will replace them is not clear.
           The key issue in any discussion of water is money. To talk about a water crisis hides intractable problems such as poverty.
           Consider the problems of water supply in Mexico City or Delhi. If you' re rich, you drink mineral water and may even have a swimming-pool--yet millions in such cities can't get safe drinking water. People talk about the coming water crisis. I believe we have one now. It is a water crisis for the poor.

      Water of the 21st Century21世紀水資源
      地球上的生命依賴于水,而且水是無法替代的。  目前人們的假設是,不管是飲用水還是農業、工業、漁業用水,我們對水的基本需要能夠得到滿足。在這一前提下,我們有兩條基本道路可走:更合理地利用水資源或建立更多大型的水利工程。


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