The Population Bomb.docx

1、The Population BombUNIT 8Text APRE-READING TASKExercise 1Before reading the passage, try to answer the questions.1. How many years do you think it takes to double the world population now?2. What might be the possible solutions to the population explosion in the world?Now compare your answers with y

2、our neighbours.The Population BombI. Too many people1 Figure and numerous facts prove that there are already, and certainly that there will be, too many people. Simply calculating the lengths of time necessary to double the worlds population is instructive. Impressively, the time required grows ever

3、 shorter: 6 000 years before Christ, 1 000 000 years were necessary to double the population, then about 1 650 years after Christ only 1 000 around the 1850s 200 years, in 1930 80 years. Currently, the worlds population doubles every 37 years.2 What would happen if the population were to continue do

4、ubling in volume every 37 years?3 According to recent calculations, maintaining such a rhythm of growth would result in 60 million billion people on the earth in 900 years, which represents 120 inhabitants per square meter.4 Optimists believe and often assert that science will indeed find solutions

5、to the problem of overcrowding, namely by providing the means to immigrate to other planets. But this solution is totally impossible. In effect, even if it should become possible, 50 years would be sufficient for the 60 million billion persons to multiply to the point of populating Venus, Mercury, M

6、ars, the Moon and the satellites of Jupiter and Saturn with a density equal to that of the Earth.II. Food Shortage5 Today, a good part of humanity suffers from malnutrition or from undernourishment.6 Some think that the recent scientific discoveries applied to agriculture and known under the name of

7、 green revolution will resolve the problem. Nothing is less certain. Promoters of the revolution themselves believe that it can offer only a respite of ten or twenty years.7 In underdevel-oped countries, al-though mostly agri-cultural, the lag in food production in relation to population growth incr

8、eases more and more. As the crisis worsens these countries will have to import food. But from where?III. A Dying Planet8 The worlds population explosion is the source of a whole series of environmental deteriorations, which in time can have disastrous consequences.9 Because the population-food imbal

9、ance makes it necessary to increase agricultural production at any price, methods often harmful to the environment are used without judgment. For example, the construction of huge dams to irrigate hundreds of thousands of acres can in fact provoke catastrophes. Thus, the Aswan Dam currently prevents

10、 the deposit of fertile silts brought each year by the flooding of the Nile. The result will obviously be a decrease in the fertility of the Delta lands. Damming the Mekong risks the same consequences for Vietnam and neighbouring countries.10 Fertilizers, synthetic pesticides, DDT can be devastating

11、, transforming complex ecosystems, necessary for the conservation of the environment, into simple ecosystems.11 Certain situations are perceived as dangerous only when they become critical enough to cause numerous deaths. Smog is an example. In London in 1952 it caused some 4 000 deaths. This incide

12、nt provoked an awakening of conscience and resulted in decisions which have proven effective. But smog presents still other dangers: namely, it destroys plants which offer little resistance, and whose oxygen production is indispensable to us, and it changes the earths thermal equilibrium.12 For thes

13、e forms of pollution as for all the others, the destructive chain of cause and effect goes back to a prime cause: too many cars, too many factories, too many detergents, too many pesticides, more and more trails left by supersonic jets, inadequate methods for disinfecting sewers, too little water, t

14、oo much carbon monoxide. The cause is always the same: too many people on the earth.New Wordsnumerousa. many 许多的,众多的instructv. 1. 教，教育2. 通知，向提供事实情况instructivea. 1. 有启发的，有教益的2. 教育的，指导性的impressivea. causing admiration by giving one a feeling of importance 给人以深刻印象的impressivelyad. 给人以深刻印象地namelyad. (and

15、) that is (to say)即，那就是immigratev. to come into a country to make ones life and home there 移居，移入multiplyv. to increase 增加populatev. (of a group) to live in (a particular area) （大批地）居住于，生活于satelliten. 1. a heavenly body, moving around a larger one 卫星2. a man-made object intended to move around the ea

16、rth, moon, etc. 人造卫星densityn. 1. 密集，稠密2. 密度undernourishmentn. 营养不足respiten. ( a short period of) pause or rest, during a time of great effort, pain, or trouble 暂缓，暂停lagn. a period of time by which something is slower or later 落后，滞后worsenv. to (cause to) become worse 变得更差，恶化deteriorationn. the state

17、of becoming worse 恶化，变坏judgmentn. the ability to judge correctly 判断damn. a wall or bank built to keep back water 坝，堤v. to build a dam across 筑坝irrigatev. to supply water to (dry land) 灌溉acren. a measure of land, about 4047 square metres 英亩(4047平方米)provokev. to cause 引起catastrophen. a sudden, unexpec

18、ted, and terrible event that causes great suffering 灾难fertilea. (of land) which produces good crops 肥沃的siltn. （水流夹带或水底沉积的）泥沙，淤泥fertilityn. the condition or state of being fertile 肥沃，丰产delta（河流的）三角洲synthetica. 1. 合成的2. 综合的pesticiden. 农药，杀虫剂transformv. to change completely in form, appearance 使改变（性质等）

19、ecosystemn. 生态系统awakeningn. the act of becoming conscious or concerned 觉醒，唤醒resistancen. the ability or power of resisting 抵抗力oxygenn. 氧，氧气indispensablea. that is too important to live without 必不可少的destructivea. 破坏性的，毁灭性的detergentn. a chemical product used for cleaning 洗涤剂trailn. a series of marks l

20、eft by a person or thing passing by 痕迹supersonica. faster than the speed of sound 超音速的adequatea. sufficient 充分的，足够的inadequatea. not adequate 不适当的，不充分的disinfectv. 消毒，杀菌carbonn. 碳monoxiden. 一氧化物Phrases and Expressionsin effect实际上，实质上be equal to等于，比得上under the name of名叫，称为suffer from遭受in relation to与相比

21、，与有关，涉及in time最终，迟早，及时at any price不惜任何代价Proper Namesbefore Christ公元前Venus金星Mercury水星Mars火星Saturn土星the Aswan Dam阿斯旺水坝the Nile尼罗河the Mekong湄公河Vietnam越南DDT滴滴涕（商品名，一种杀虫剂）Text BPRE-READING TASKExercise 1Before reading the passage, think about the questions.1. What would it be like if there were no trees

22、on the earth?2. Why is it important for us to plant more trees nowadays?Now read the passage and check your answers with the authors.Reforest the Earth!1 Throughout the drought-ridden summer of 1988, the world heard much about how the burning of fossil fuels causes the greenhouse effect (the rapid w

23、arming of the earths atmosphere.) We heard little about how the burning of tropical rain forests also contributes to the greenhouse effect. And still less do we hear about how reforestation of these tropics could help heal an ailing world.2 The earth constantly maintains 700 billion metric tons of c

24、arbon dioxide (CO2) in the atmosphere. Fossil fuels emit another 5.2 billion metric tons of CO2 into the air each year, while the burning of tropical forests emits roughly 1.8 billion metric tons of CO2 - both contributing to a buildup of carbon dioxide that will soon trigger the greenhouse effect.

25、The CO2 gases trap the heat of the sun in the same way the glass of a greenhouse controls temperature for plants. If the gases become too concentrated, too much heat will collect, resulting in rising temperatures.3 Of all the carbon dioxide emitted into the atmosphere, only about half accumulates in

26、 the skies while the rest disappears into oceans and lakes, vegetation and soil. So out of the 5.2 billion metric tons of CO2 emitted from the burning of fossil fuels and the 1.8 billion metric tons released from the burning of rain forests each year, only 3.5 billion metric tons contributes to glob

27、al warming.4 In 1980, 36 000 square miles of forest were burned in the tropics. In 1987, 33 000 square miles of rain forest were burned in Brazilian Amazonia alone. By the year 2020 the figure for tropical-forest emissions of CO2 could climb to another 5 billion metric tons. As a result, the CO2 rel

28、eased into the atmosphere each year would rise to approximately 10.2 billion metric tons.5 Replanting trees in the tropics could eventually offer a solution to the greenhouse effect. A tree absorbs carbon dioxide through photosynthesis. Plant enough trees (as many as 250 billion) and we could remove

29、 much of the additional CO2 building up in the atmosphere. Nowhere in the world are conditions better for growing trees than in the tropics, where year-round warmth and moisture encourage rapid growth. To start a grand-scale tree-growing project in the tropics, however, would require as many as 20 g

30、overnments in Latin America, Africa, and Asia to stop the rapid destruction of rain forests.6 How many trees would we need to reforest the earth and stabilize the damage produced by global warming? One acre of a tropical plantation can absorb an annual average of four metric tons of atmospheric carb

31、on. In order to soak up 1 billion metric tons of CO2, we would have to plant 400 000 square miles of new tropical forests. To eliminate the buildup of 3.5 billion metric tons would require planting trees on 1.2 million square miles, an expanse roughly equivalent to all states east of the Mississippi.7 Where can we find enough space to replant what isnt being otherwise utilized? In the humid tropics forests have been cut down in watershed regions where replanting is urgently needed to stop