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21世紀(jì)的水質(zhì) Water quality in twenty-first Century

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2018年06月13日

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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.

地球上的生命取決于水,沒(méi)有任何替代品。目前的假設(shè)是,我們的基本需求是水,無(wú)論是飲用水,農(nóng)業(yè),工業(yè)還是魚(yú)的養(yǎng)殖--都必須滿(mǎn)足。既然有這樣的前提,我們可以走兩條基本路線。更公平地獲得水或更激烈的工程解決方案。在工程解決方案的第一,我的研究集中在什么情況下,當(dāng)你在河流域,特別是在非洲建設(shè)的濕地發(fā)生了什么。這類(lèi)地區(qū)的生態(tài)環(huán)境幾乎完全被季節(jié)變化所驅(qū)動(dòng)--水的脈搏。而事實(shí)是,如果你建一座水壩,你一般會(huì)破壞下游的生態(tài)環(huán)境。在過(guò)去,這樣的問(wèn)題已經(jīng)被隱藏的信息缺乏。但在下個(gè)世紀(jì),政府將沒(méi)有任何借口為自己的無(wú)知。工程師們控制水流的能力也創(chuàng)造了新的不可預(yù)測(cè)性。在非洲的水壩意味著更少的魚(yú),更少的放牧和更少的洪泛區(qū)農(nóng)業(yè)--沒(méi)有一個(gè)被預(yù)期。他們的平均經(jīng)濟(jì)生活被假定為三十年。大壩不存在,但什么將取代它們是不明確的。水的任何討論中的關(guān)鍵問(wèn)題是金錢(qián)。談?wù)撍C(jī)隱藏棘手的問(wèn)題,如貧困??紤]墨西哥市或德里的供水問(wèn)題。如果你很富有,你喝礦泉水,甚至可能有一個(gè)游泳池,但數(shù)以百萬(wàn)計(jì)的人在這樣的城市不能得到安全飲用水。人們談?wù)摷磳⒌絹?lái)的水危機(jī)。我相信我們現(xiàn)在有一個(gè)。這是一個(gè)貧窮的水危機(jī)。

 


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