21世纪的水质-尊龙ag旗舰官网

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.

标题：21世纪（21世纪的水水质）

内容：21世纪的生命之水在地球上依赖于水，没有任何替代品。目前的假设是，我们的基本需要的水不论是饮用，农业，工业或鱼提高- - 将永远得到满足。鉴于这个前提下，有两个基本路线，我们可以走了。更公平地获得水或更激烈的工程尊龙ag旗舰官网的解决方案。在工程尊龙ag旗舰官网的解决方案：第一，我看很多研究集中在湿地会发生什么时，建立流域水坝，特别是在非洲。这种生态地区几乎完全驱使河流季节变化 - 水的脉搏。而事实是，如果你建立一个大坝，您通常下游生态破坏。在过去，这类问题都得到了隐藏信息的缺乏。但在下一世纪，政府将不会对他们的幸福无知的借口。工程师们能够控制水流，造就了不可预测的新种了。在非洲'水坝就意味着少鱼，少放牧和农业少漫滩 - 没有一个人的预期。而他们的平均经济生活中假定为三十年。水坝不存在下去，但它们将取代目前尚不清楚。在任一水讨论的主要问题是资金。谈水危机的隐藏，如贫困棘手的问题。考虑到水在墨西哥城和德里供应的问题。如果您'再丰富，喝矿泉水，甚至有一个游泳池 - 然而，在这样的城市数以百万计不能得到安全的饮用水。人们在谈论未来的水危机。我相信我们现在有一个。这是对穷人的水危机。

本文由大学英语网提供!