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1、 Unit 1 Man&Nature广东理工学院大学英语3Warm-upDo you think we humans are to blame for the deterioration of our environment Why or why not Are there any environmental problems where you live What would you suggest to solve them What should every one of us do to protect our environment Background Knowledge A ra
2、inforest is a forested biome(生生物物群群系系)with high annual rainfall.Some cite a minimum normal annual rainfall of 2500 mm(about 100 inches or 250 centimeters),with normal rainfall at least 60 mm during each of the twelve months of the year.Others set the minimum annual rainfall barrier as low as 1700 mm
3、(about 67 inches).As well as prodigious rainfall,many rainforests are characterized by a high number of resident species and tremendous biodiversity.Rainforests once covered 14%of the earths land surface;now they cover a mere 6%.One and one-half acres of rainforest are lost every second with tragic
4、consequences for both developing and industrial countries,and experts estimate that the last remaining rainforests could be consumed in less than 40 years.Background Knowledge Rainforests are being destroyed because the value of rainforest land is perceived as only the value of its timber by short-s
5、ighted governments,multinational logging companies,and land owners.Nearly half of the worlds species of plants,animals and microorganisms live in rainforests and they would be destroyed or severely threatened by rainforest deforestation.Millions of Indians live in the Amazonian Rainforest(the worlds
6、 largest rainforest),but because of rainforest deforestation,their numbers are reducing rapidly,too.Preparation1.What is so special about the rainforest life?One of the most remarkable things about rainforest life is its diversity.Researchers estimate that in a large rainforest area,there may be ove
7、r 10 million different animal species.Rainforest plant life is similarly diverse.You may find 300 distinct treespecies in a tropical rainforest.Preparation2.Why do rainforests play a key role in global ecosystem?Because their dark depths absorb heat fromthe sun.Without the forest cover,these regions
8、 would reflect more heat into the atmosphere,warming the rest of the world.Preparation3.What will be the consequences of destroying rainforests?Many unique life forms will die out;more heat will be reflected into the atmosphere,warming the rest of the world;there will be a reduction in food supplies
9、;rainforest plantswith medicinal properties will vanish and we will lose valuable medicines;rainforest tribes will disappear and theirextensive knowledge of the vast resources of the rainforestwill be lost to us.Rainforests A rainforest is an environment that receives high rainfall and is dominated
10、by tall trees.Most of the time when people talk about rainforests,they mean the tropical rainforests located near the equator.译文 1One of the most remarkable things about rainforest life is its diversity.2Researchers estimate that in a large rainforest area,there may be over 10 million different anim
11、al species.3And a great number of species living in other environments now,including humans,originally inhabited the rainforests.4Rainforest plant life is similarly diverse.You may find 300 distinct tree species in a tropical rainforest.译文 1Tropical rainforests used to be referred to as the“lungs of
12、 the world”because of the large amount of oxygen they produce.2However,more recent evidence suggests that rainforests dont have much of an effect on the worlds oxygen supply.The decomposition of dead plant matter consumes roughly the same amount of oxygen that living plants produce.译文 1But rainfores
13、ts do play a key role in the global ecosystem.Some experts are now calling them the“air conditioners to the world”,2because their dark depths absorb heat from the sun.3Without the forest cover,these regions would reflect more heat into the atmosphere,warming the rest of the world.译文 Rainforests are
14、an extremely valuable natural resource.Approximately 80 percent of the food we eat originated in tropical rainforests.Without rainforests,we wouldnt have the seeds that produce coffee and chocolate,nor would we have tomatoes,potatoes,rice,bananas,pineapples and corn.There are over 3,000 fruits found
15、 in rainforests.Westerners use about 200 of them,but the indigenous tribes make use of over 2,000.译文 Rainforests are often called the worlds pharmacy.Over 25 percent of our medicines come from plants that originated in rainforests,and 1these plants make up only a tiny fraction of the total collectio
16、n of rainforest species.2Fewer than one percent of rainforest plants have been examined for their medicinal properties.3It is likely that our best shot at curing cancer,AIDS and many other diseases lies somewhere in the worlds diminishing rainforests.译文 1However,in the past hundred years,humans have been destroying rainforests at an alarming rate.Today,roughly 1.5 acres of rainforests are destroyed every second.2One major problem with deforestation is the devastating effect it has on rainforest
