21世紀的水質(zhì) Water of the 21st Century
Water of the 21st Century
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. 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.
21世紀(21世紀的水水質(zhì))
內(nèi)容：21世紀的生命之水在地球上依賴于水，沒有任何替代品。目前的假設(shè)是，我們的基本需要的水不論是飲用，農(nóng)業(yè)，工業(yè)或魚提高- - 將永遠得到滿足。鑒于這個前提下，有兩個基本路線，我們可以走了。更公平地獲得水或更激烈的工程解決方案。在工程解決方案：第一，我看很多研究集中在濕地會發(fā)生什么時，建立流域水壩，特別是在非洲。這種生態(tài)地區(qū)幾乎完全驅(qū)使河流季節(jié)變化 - 水的脈搏。而事實是，如果你建立一個大壩，您通常下游生態(tài)破壞。在過去，這類問題都得到了隱藏信息的缺乏。但在下一世紀，政府將不會對他們的幸福無知的借口。工程師們能夠控制水流，造就了不可預(yù)測的新種了。在非洲'水壩就意味著少魚，少放牧和農(nóng)業(yè)少漫灘 - 沒有一個人的預(yù)期。而他們的平均經(jīng)濟生活中假定為三十年。水壩不存在下去，但它們將取代目前尚不清楚。在任一水討論的主要問題是資金。談水危機的隱藏，如貧困棘手的問題。考慮到水在墨西哥城和德里供應(yīng)的問題。如果您'再豐富，喝礦泉水，甚至有一個游泳池 - 然而，在這樣的城市數(shù)以百萬計不能得到安全的飲用水。人們在談?wù)撐磥淼乃C。我相信我們現(xiàn)在有一個。這是對窮人的水危機。
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