环境工程专业英语unit2教案资料.ppt

环境工程专业英语unit2lWater is critical component of ecological cycles.水是生态循环的关键组分。水是生态循环的关键组分。lAquatic ecosystems harbor diverse species and offer many valuable services.harbor，vt.隐匿，窝藏，庇护隐匿，窝藏，庇护 diverse，不同的，多种多样的，不同的，多种多样的 水生态系统养护着很多的物种，同时提供许多有价值水生态系统养护着很多的物种，同时提供许多有价值的服务。的服务。Unit 2 The world fresh water resourcelHuman beings require water to run industries,to provide energy,and to grow food.人类需要水，使工厂运转，提供能源，生产食物。人类需要水，使工厂运转，提供能源，生产食物。lIn order to mobilize water for human needs,we build huge reservoirs to store water for dry periods and to hold back flood waters;为了使水能够满足人们的需求，我们修建了大型为了使水能够满足人们的需求，我们修建了大型水库，以为干旱时期储存水和蓄积洪水。水库，以为干旱时期储存水和蓄积洪水。Unit 2 The world fresh water resourcelwe build aqueducts to transport water thousands of kilometers from water-rich to water-poor regions;我们修建渠道，把水从水量充足的地方输送到几千公我们修建渠道，把水从水量充足的地方输送到几千公里以外缺水的地方。里以外缺水的地方。lwe burn oil to generate electricity to desalinate salt water in arid regions;我们燃烧石油用来发电，用于干旱地区的盐水淡化处我们燃烧石油用来发电，用于干旱地区的盐水淡化处理。理。Unit 2 The world fresh water resourceland we dream of towing icebergs from the polar regions and of reversing the flow of massive rivers.我们梦想着从极地拖动冰山，让大河逆流。我们梦想着从极地拖动冰山，让大河逆流。Unit 2 The world fresh water resourcelHarsh realities intrude on these dreams.intrude on，入侵，闯入，打扰，入侵，闯入，打扰 严酷的事实打碎了这些梦。严酷的事实打碎了这些梦。lAs we approach the 21st century we must now acknowledge that many of our efforts to harness water have been inadequate or misdirected.Harness，vt.利用利用,征服征服 随着我们迈进随着我们迈进21世纪，我们必须认识到，我们为了世纪，我们必须认识到，我们为了征服水而做的许多努力都是不适当的或错误的。征服水而做的许多努力都是不适当的或错误的。Unit 2 The world fresh water resourcelWe remain ignorant of the functioning of basic hydrologic processes.我们对基本水文过程的功能仍然无知。我们对基本水文过程的功能仍然无知。lRivers,lakes,and ground water aquifers are increasingly contaminated with biological and chemical wastes.ground water，地表水，地表水 生物和化学废物对河流、湖泊和地表水层的污染一直生物和化学废物对河流、湖泊和地表水层的污染一直在加深。在加深。Unit 2 The world fresh water resourcelVast numbers of people lack clean drinking water and rudimentary sanitation services.很多的人缺乏洁净的饮用水和基本的卫生设施服务。很多的人缺乏洁净的饮用水和基本的卫生设施服务。lMillions of people die every year from water-related diseases such as malaria,typhoid,and cholera.每年有数百万的人死于由水引起的疾病，如疟疾、伤每年有数百万的人死于由水引起的疾病，如疟疾、伤寒和霍乱。寒和霍乱。Unit 2 The world fresh water resourcelMassive water developments have destroyed many of the worlds most productive wetlands and other aquatic habitats.大规模的水的开发已经损害了世界上许多最富于大规模的水的开发已经损害了世界上许多最富于生产力的湿地和其它的水生栖息地环境。生产力的湿地和其它的水生栖息地环境。Unit 2 The world fresh water resourceUnit 2 The world fresh water resourcelThe economic and hydrologic resources for major new irrigation projects cannot be found.l大多数农田水利项目所需要的经济和水资源无法找到。大多数农田水利项目所需要的经济和水资源无法找到。lAnd expected changes in global climatic conditions will alter future water supply,demand,and quality.l继期望改变全球气候条件之后继期望改变全球气候条件之后,将是对水源、水量和水质将是对水源、水量和水质改变的期望。改变的期望。Unit 2 The world fresh water resourcelHindu and Buddhist traditions place mythical Mount Meru the dwelling place of the godsat the center of the universe.lHindu and Buddhist traditions 印度教与佛教传说印度教与佛教传说l在印度教和佛教传说中，神居住在宇宙的中心在印度教和佛教传说中，神居住在宇宙的中心神秘的神秘的Meru山上。山上。lHere originate the rivers of the earth,including the Indus,the Ganges,and the Brahmaputra.l所以地球河流的起源包括印度河、恒河和布拉马普特拉河所以地球河流的起源包括印度河、恒河和布拉马普特拉河（雅鲁藏布江雅鲁藏布江）。）。Unit 2 The world fresh water resourcelIn early Christian tradition,the waters of the earth originate in the fountains of the Garden of Eden,which divide into the worlds great streams:the Nile,the Tigris,the Euphrates,the Indus,and the Ganges.lWhich指代前文的指代前文的waters。l早期的耶督教传说中，地球上的水来自于伊甸园的泉水；早期的耶督教传说中，地球上的水来自于伊甸园的泉水；这些水又分流世界上的各大河流：尼罗河、底格里斯河、这些水又分流世界上的各大河流：尼罗河、底格里斯河、幼发拉底河、印度河和恒河。幼发拉底河、印度河和恒河。Unit 2 The world fresh water resourcelThese myths arise in part from the sacred role of water in sustaining life,and in part from our ignorance of the functioning of the global water cycle.l这些神话的出现，一方面是因为水在维持生命中的重要作这些神话的出现，一方面是因为水在维持生命中的重要作用，还因为人们对于地球水循环功能的无知。用，还因为人们对于地球水循环功能的无知。Unit 2 The world fresh water resourcelBy the end of the 20th century,our understanding of the stocks,flows,and condition of global water resources is still distressingly imperfect.l20世纪末期，我们对全球水资源存储、流动、和条件的理世纪末期，我们对全球水资源存储、流动、和条件的理解仍然是很不完美的。解仍然是很不完美的。Unit 2 The world fresh water resourcelThe International Hydrological Decade,coordinated by the United Nations Educational,Scientific,and Cultural Organization(UNESCO),beginning in the mid 1960s,was successful in elucidating many unknown aspects of the global hydrological cycle and some of the best references on global water resources still date from that period.l始于始于20世纪世纪60年代中期的年代中期的“国际水文学十年国际水文学十年”活动，由联活动，由联合国教科文组织协调，对全球水循环中尚不清楚的原理进合国教科文组织协调，对全球水循环中尚不清楚的原理进行了成功阐述，同时还介绍了当时有关地球水资源方面最行了成功阐述，同时还介绍了当时有关地球水资源方面最好的文献书目。好的文献书目。Unit 2 The world fresh water resourcelUnfortunately,with the exception of the United Nations International Drinking Water Supply and Sanitation Decade from 1981 to 1990,there has been little follow-up on understanding and solving critical water issues,and much of the momentum of that earlier period has been lost.l不幸的是，除去不幸的是，除去1981-1990年的年的“联合国国际饮用水供给联合国国际饮用水供给和卫生十年和卫生十年”的活动外，对于认识和解决重要水问题的后的活动外，对于认识和解决重要水问题的后续活动很少，以前的对于这方面的动力也已经没有了。续活动很少，以前的对于这方面的动力也已经没有了。Unit 2 The world fresh water resourcelSamuel taylor Coleridge(17721834),in his classic poem“The rime of the Ancient Mariner”,effectively described the principal characteristic of the earths water resources when he wrote,“water,water,everywhere,nor any drop to drink”.lSamuel taylor Coleridge在他著名的诗词在他著名的诗词“古老水手古老水手”中写到：水，随处都有，但不是所有都能饮用，这准确描中写到：水，随处都有，但不是所有都能饮用，这准确描述了地球水资源的基本特征。述了地球水资源的基本特征。Unit 2 The world fresh water resourcel97%of all the water on earth is salt waterunsuitable for drinking or growing crops.l地球总水量的地球总水量的97%是咸水，不适于饮用或种植庄稼。是咸水，不适于饮用或种植庄稼。lThe remaining 3%is fresh water,comprising a total volume of about 35 million km3.if this water were spread out evenly over the surface of the earth it would make a layer 70 m thick.l剩余的剩余的3%是淡水，约有是淡水，约有35,000,000,000m3。如果将这部分水。如果将这部分水平均铺在地球表面平均铺在地球表面,约有约有70米厚。米厚。Unit 2 The world fresh water resourcelYet almost all of this fresh water is effectively locked away in the ice caps of Antarctica and Greenland and in deep underground aquifers,which remains technologically or economically beyond our reach.l然而这部分淡水中的大部分被固定在南极洲和格陵兰岛的冰盖然而这部分淡水中的大部分被固定在南极洲和格陵兰岛的冰盖中，或被深埋在低下深层，是人类在技术和经济上不能达到的。中，或被深埋在低下深层，是人类在技术和经济上不能达到的。Unit 2 The world fresh water resourcelLess than 100000 km3just 0.3%of total fresh water reserves on earthis found in the rivers and lakes that constitute the bulk of our useable supply.l地球淡水总储量的地球淡水总储量的0.3%，不足，不足100000000m3，储存于河流储存于河流和湖泊中，是我们能够利用的主要水量。和湖泊中，是我们能够利用的主要水量。Unit 2 The world fresh water resourcelFresh water is a renewable resource made continuously available by the constant flow to the earth of solar energy,which evaporates water from the oceans and land and redistributes it around the globe.l借助于太阳能向地球表面的稳定传输，水从海洋和陆地表借助于太阳能向地球表面的稳定传输，水从海洋和陆地表面蒸发，并被在全球重新分配，淡水成为了一种可以连续面蒸发，并被在全球重新分配，淡水成为了一种可以连续获得的可再生资源。获得的可再生资源。Unit 2 The world fresh water resourcelMore water evaporates from the oceans than falls on them as precipitation;thus there is a continuous transfer of fresh water from the oceans to the continents.l海洋的蒸发量大于降雨量；因此存在从海洋向陆地的连续的淡海洋的蒸发量大于降雨量；因此存在从海洋向陆地的连续的淡水传输。水传输。lThis water runs off in the rivers and streams that sustain our natural ecosystems and societies and recharge our aquifers.l这部分水流到河流中，维持自然生态系统和社会，或补给地下这部分水流到河流中，维持自然生态系统和社会，或补给地下蓄水层。蓄水层。Unit 2 The world fresh water resourcelOn an annual basis,about 45000 km3 per year are returned to the oceans as river and groundwater runoff.l以年度为基础，每年大约有以年度为基础，每年大约有45000000m3的水以河流和地下的水以河流和地下径流方式回到海洋。径流方式回到海洋。l If that runoff were evenly distribute,each person on earth would receive more than 8000 m3 per year.l如果这部分径流被平均地分配，地球上每个人每年获得的水如果这部分径流被平均地分配，地球上每个人每年获得的水量超过量超过8000 m3。Unit 2 The world fresh water resourcelIn fact,these fresh water resources are not evenly distributed.Rainfall and runoff are apportioned in both space and time in a grossly irregular manner.l事实上，这些淡水资源是不能平均分配的。降水和径流在事实上，这些淡水资源是不能平均分配的。降水和径流在时空上呈现无规律分配状态。时空上呈现无规律分配状态。lWe often dont get water when we need it or where we need it.Some places receive enormous quantities;others receive almost none.l在我们需要的时候或需要的处所，我们不是总能得到水。在我们需要的时候或需要的处所，我们不是总能得到水。一些地方的水过量，而另一些地方几乎没有一点。一些地方的水过量，而另一些地方几乎没有一点。Unit 2 The world fresh water resourcelThe Atacama Desert in South America is one of the worlds driest areas.The rain gauge at Arica,Chile routinely records zero annual precipitation.l处于南美洲的阿塔卡马沙漠是世界上最干旱的区域之一。处于南美洲的阿塔卡马沙漠是世界上最干旱的区域之一。智利阿里卡地区每年的降雨记录为零。智利阿里卡地区每年的降雨记录为零。lPictures from space reveal cloudless skies over the great Sahara desert of Africa.l来自高空的照片展现了非洲撒哈拉大沙漠无云的天空。来自高空的照片展现了非洲撒哈拉大沙漠无云的天空。Unit 2 The world fresh water resourcelAt the other extreme,Mount Waialeale,on the island of Kauai,Hawaii has recorded more than 11.5 m of rainfall in a single year.l另一个极端的情况，夏威夷考艾岛的另一个极端的情况，夏威夷考艾岛的Waialeale山，有记录某一山，有记录某一年的降雨量超过了年的降雨量超过了11.5 m。lOther examples of these severe distribution problems abound.Twenty per cent of global average runoff comes from the Amazon River alone.l关于这类严重分配不均的问题还有许多事例。全球平均径流的关于这类严重分配不均的问题还有许多事例。全球平均径流的20%来自于亚马逊河。来自于亚马逊河。Unit 2 The world fresh water resourcelAll of Europe accounts for only 7%of global runoff;all of Australia produces only 1%.l整个欧洲的径流只有全球的整个欧洲的径流只有全球的7%；澳大利亚的只有；澳大利亚的只有1%。lThirty per cent of the total runoff in Africa comes from a single river basin,the Congo/Zaire.l非洲总的径流量的非洲总的径流量的30%来都自于刚果来都自于刚果/扎伊尔河盆地。扎伊尔河盆地。Unit 2 The world fresh water resourcelMany regions get nearly 100%of their precipitation during a brief,intense rainy season.l许多区域的雨季都来自于短暂而降雨强度大的雨季。许多区域的雨季都来自于短暂而降雨强度大的雨季。lIn Cheerapunji,India,over 10.5 m of rain per year may fall during the brief period of the monsoon.l在印度的在印度的Cheerapunji，每年的降雨量超过，每年的降雨量超过10.5 m，却都，却都集中在短暂的季风期。集中在短暂的季风期。Unit 2 The world fresh water resourcelMuch of California gets no rainfall at all from May through September,which is precisely the period of greatest water demand.l加利福尼亚的许多地方，从五月到九月没有降雨，而这时加利福尼亚的许多地方，从五月到九月没有降雨，而这时恰是需水量最大的时候。恰是需水量最大的时候。Unit 2 The world fresh water resourcelFig.1-2 shows the annual per capita availability of fresh water by continent.大洋州大洋州 南美洲南美洲 北美洲和中美洲北美洲和中美洲 非洲非洲 欧洲欧洲 亚洲亚洲807060504030201001000m3/人人 年年图图1-2图示了每个洲每年图示了每个洲每年每人可以获得的淡水量。每人可以获得的淡水量。Unit 2 The world fresh water resourcelOceania,because of its low population and large water resources,offers more than twenty times as much fresh water per person as does Asia.l大洋州人口密度低但有巨大的水资源量，每人拥有的淡大洋州人口密度低但有巨大的水资源量，每人拥有的淡水量超过了亚洲的水量超过了亚洲的20倍之多。倍之多。lThis tremendous variability is a natural feature of our climate and helps define many of the problems facing us today.l这种巨大的差异是由于气候所造成的，并导致了我们今这种巨大的差异是由于气候所造成的，并导致了我们今天所面临的许多问题。天所面临的许多问题。Unit 2 The world fresh water resourcelShiklomanov argues that solving our water problems requires that we expand our study of these natural characteristics,improve our ability to assess both static and dynamic hydrologic processes,and incorporate the effects of human economic activities and growing populations into our understanding of the global water cycle.lShiklomanov指出，为了解决我们的水问题，需要对自然指出，为了解决我们的水问题，需要对自然特性展开研究，提高我们评估水的静态和动态过程、以及特性展开研究，提高我们评估水的静态和动态过程、以及将人们的经济活动和人口增长与全球水循环结合起来的能将人们的经济活动和人口增长与全球水循环结合起来的能力。力。Unit 2 The world fresh water resourcelThese actions will require far more effective international cooperation on water issues than we have seen before.l这些活动需要我们在水问题方面做比以前更有效的这些活动需要我们在水问题方面做比以前更有效的国际间活动。国际间活动。此课件下载可自行编辑修改，仅供参考！此课件下载可自行编辑修改，仅供参考！感谢您的支持，我们努力做得更好！谢谢感谢您的支持，我们努力做得更好！谢谢