高级英语(第三版)第二册第十一课-Four-Laws-of-Ecology-Part-I)课件

省级精品课程,高级英语,第三版第二册,制作人：徐李洁,单击此处编辑母版标题样式,单击此处编辑母版文本样式,第二级,第三级,第四级,第五级,*,单击此处编辑母版标题样式,单击此处编辑母版文本样式,第二级,第三级,第四级,第五级,*,单击此处编辑母版标题样式,单击此处编辑母版文本样式,第二级,第三级,第四级,第五级,*,Lesson Eleven,Four Laws of Ecology(1),-Barry Commoner,Lesson Eleven,Teaching Objectives,To enable students to understand Commoners concepts of four laws of ecology.,To familiarize students with vocabulary concerning ecosystem,environmental crisis and biological terms.,To appreciate the writing style.,Teaching Objectives To enable,an American environmental scientist,also an author and a strong social activist.A member of the American Association for the Advancement of Science.,Received his bachelors degree in zoology from Columbia University(1917)and his masters and doctoral degrees from Harvard University(1941).,a professor of plant physiology at,Washington University,for 34 years.,In 1966,he founded the,Center for the Biology of Natural Systems,to study the science of the total environment.,In 1970 he received the International Humanist Award from the International Humanist and Ethical Union.,In 1980,he founded the Citizens Party to serve as a vehicle for his ecological message.,He ran for President of the United States in the 1980 US Election,yet unsuccessful.,He criticized Ronald Reagan and George Bush for regulating pollution and not presenting it.,Barry Commoner,(1917 2012),an American environmental scie,Commoners Books,In the 1950s,Commoner began to push for atmospheric testing of nuclear weapons,thereby bringing himself into public prominence.In the 1960s,he became involved in other environmental issues;these included pollution and energy sources.,He gave speeches and wrote numerous books:,Science and Survival,(1967),The Closing Circle,(1971),Energy and Human Welfare,(1975),The Poverty of Power,(1976),The Politics of Energy,(1979),Making Peace with the Planet,(1990).,Commoners Books In the 1950s,Commoners Views,library.thinkquest.org/26026/People/barry_commoner.html,Among his views,Commoner believes that industrial methods,especially those involving,fossil fuels,are causing environmental pollution.He feels strongly that the quest for maximum profit currently takes priority over environmental reasoning.Commoner also believes that it is pointless to try to undo the environmental damage we have caused;this is a losing battle.We should instead focus on preventing future destruction;for the most part,the solution to environmental problems lies in not destroying the environment in the first place.,Commoners solutions for many problems are considered radical.He is a strong advocate of,renewable energy,sources,specifically,solar energy,which would decentralize electric utilities and use sunlight as an alternative power source for most energy consumers.,Commoner also has strong views on social causes of the present environmental situation.He argues,for example,that eliminating Third World debt payments would lesson the economic gap between developed and less developed countries and end the desperation that usually results in,overpopulation,.This debt forgiveness could also compensate for previous decades of damage inflicted on such countries.Commoner also calls for redistribution of the worlds wealth.,Commoner combined his socialist and environmental beliefs in a brief Citizens Party presidential campaign in 1980.For the past nearly twenty years,he has directed the Center for the Biology of Natural Systems at Queens College in New York City.,Commoners Viewslibrar,The Closing Circle:Nature,Man,and Technology,abestseller,In this book Commoner suggests that the American economy should be restructured to conform to the unbending laws of ecology.For example,he argued that polluting products(like detergents or synthetic textiles)should be replaced with natural products(like soap or cotton and wool).This book is one of the first to bring the idea of,sustainability,to a mass audience.Commoner suggested a left-wing,eco-socialist,response to the,limits to growth,thesis,postulating that capitalist technologies were chiefly responsible for environmental degradation,as opposed to population pressures.,He has a long running debate with,Paul R.Ehrlich,author of,The Population Bomb,and his followers,arguing that they were too focused on,overpopulation,as the source of environmental problems,and that their proposed solutions were politically unacceptable because of the coercion that they implied,and because the cost would fall disproportionately on the poor.He believed that technological,and above all social development would lead to a natural decrease in both population growth and environmental damage.,The Closing Circle:Nature,Ma,The Poverty of Power,a bestseller,Commoner addressed the Three Es that were plaguing the United States in the 1970s:,First there was the threat to,environmental survival,;,then there was the apparent shortage of,energy,;,and now there is the unexpected decline of theeconomy.,He argued that the three issues were interconnected:the industries that used the most energy had the highest negative impact on the environment;the focus on non-renewable resources as sources of energy meant that those resources were growing scarce,thus pushing up the price of energy and hurting the economy.Towards the books end,Commoner suggested that the problem of the Three Es is caused by the capitalistic system and can only be solved by replacing it with some sort of socialism.,The Poverty of Power,a bestse,“Four Laws of Ecology”is taken from Chapter Two “The Ecosphere(,生物圈）”,of,The Closing Circle,.,Everything is Connected to Everything Else.,There is one ecosphere for all living organisms and what affects one,affects all.,Everything Must Go Somewhere.,There is no“waste”in nature and there is no“away”to which things can be thrown.,3.Nature Knows Best.,Humankind has fashioned technology to improve upon nature,but such change in a natural system is,“likely to be detrimental to that system.”,4.There Is No Such Thing as a Free Lunch.,Exploitation of nature will inevitably involve the conversion of resources from useful to useless forms.,“Four Laws of Ecology”is take,About The Text,Lesson Eleven is mainly about the first two of the four basic laws of ecology.,The author discusses in depth the relationship and links of species in the ecosystem.,About The TextLesson Eleven is,Structure of the Text,Part I:Paras.1-3,This part introduces the basic concept of ecology.It also provides the discussion boundary for the following two laws.,Part II:Paras.4-18,The First Law of Ecology,Paras.4-9 Concept and examples of cybernetics,Paras.10-16 Collapse of oscillating system,Para.17 The feedback characteristics of ecosystems.,Para.18 Conclusion and restatement,Part III:Paras.19-21,The Second Law of Ecology,Structure of the TextPart I:P,Paraphrasing(Paras.118),(para.1)In broad outline,there are environmental cycles which govern the behavior of the three global systems.,Generally speaking,environmental cycles control and regulate the behavior of the three great ecological systems of the planet.,Environmental cycle:it is a natural process in which elements are continuously cycled in various forms between different compartments of the environment(e.g.air,water,soil,organisms.)for example,the water cycle is the process by which water travels in a sequence from the air to the earth and returns to the atmosphere.It is also referred to as the hydrologic cycle(,水体循环）,.,Paraphrasing(Paras.118)(par,(para.1)Each species is suited to its particular environmental niche,and each,through its life processes,affects the physical and chemical properties of its immediate environment.,Each species is suited to its particular place of function within its ecosystem.All living things must perform life processes and through these processes they affect the physical and chemical qualities of the environment that is near them.,Life processes:all living things must do all the seven life processes:respiration,nutrition,growth,moving,being sensitive or responding,excretion and reproduction.,(para.1)Each species is suite,(para.2)These links are bewildering in their variety and marvelous in their intricate detail.,The varieties of these links are confusing and their complicated details are amazing.,All this,many times multiplied and organized species by species in intricate,precise relationships,makes up the vast network of life on the earth.,This is a concluding remark to sum up all the examples given above.In reality this is added many times and organized species by species in precise relationships with many details.And this makes up the huge network of life on the earth.,(para.2)These links are bewil,(para.3)It is the science of planetary housekeeping.,Metaphor.Ecology is the science about how the affairs of our house,the planet,are managed.,It is a young science and much of what it teaches has been learned from only small segments of the whole network of life on the earth.,Ecology is a newly developed science and much of what it teaches has been learned from only small parts of the whole network of life on the earth,.,Ecology has not yet explicitly developed the kind of cohesive,simplifying generalizations exemplified by,say,the laws of physics.,Ecology is not a mature science like other natural sciences such as physics,which has clearly developed simplifying general statements and guidelines which are well-connected and well-related in a reasonable way.,say:suggest,suggest,比如说,(para.3)It is the science o,(para.4)It reflects the existence of the elaborate network of interconnection in the ecosphere.,This sentence expresses the meaning of the first law.The ecosphere is an elaborate network,in which each component part is connected to many others.This happens among different living organisms,and between populations,species,and individual organisms and physical and chemical surroundings.,The First law of Ecology:Everything is Connected to Everything Else(Paras 4-18),(para.4)It reflects the exist,(para.5)Our ability to picture the behavior of such systems has been helped considerably by the development,even more recent than ecology,of the science of cybernetics.,The development of the science of cybernetics has greatly helped our ability to describe the behavior of ecosystems.The science of cybernetics is even younger than the science of ecology,.,Cybernetics(,控制论）,:coined from the Greek word“kubernetike”(the art of the steersman),cybernetics involves the theory of regulation and of signal transmission applied to technical devices,living beings and even societies.,The term was introduced to the world by the book,Cybernetics or Control and Communication in the Animal and the Machine,published in 1948.,We owe the basic concept,and the word itself,to the inventive mind of the late Norbert Wiener.,We give credit for this basic concept and the word itself to the inventive mind of Norbert Wiener.,(para.5)Our ability to pictu,Paragraph 6 is devoted to the explanation of cyberstics by using analogy of a ship.,Paragraph 7 discusses the cybernetics systems in ecological cycles.,(para.7)in quite a similar way,stabilizing cybernetic relations are built into an ecological cycle.,The ship system represents a mechanical cycle.Similar to this cycle,cybernetics systems with stabilizing effects are an integral part of an ecological cycle.,The phrase“in quite the same way”enables a smooth transition.,Built into:to make an integral part of,Paragraph 6 is devoted to the,Paragraph 9 is an example about the periodic rabbit-lynx fluctuations(,波动）,.,Lynx:a large wild cat that has no tail and lives in forests(,猞猁）,(para.9)ecological systems exhibit similar cycles,although there are often obscured by the effects of daily or seasonal variations in weather and environmental agents.,Ecological systems display cycles similar to those described above,but they are often not easily seen because of the impacts of daily or seasonal changes in weather and environmental elements and effects.,the lynx population is positively related to the number of rabbits and the rabbit population is negatively related to the number of lynx.,More rabbits provide more food for lynx and thus the rising population of rabbits increases the population of the lynx.reversely.When there are more lynx,rabbits are more fiercely hunted and consumed,and as a result the population of the rabbits decreases.This explains the use of the words“positively”and“negatively”.,Paragraph 9 is an example abou,Paragraph 10 explains under what conditions an oscillating system may break down completely.,(para.10)In such an oscillating system,there is always the danger that the whole system will collapse when an oscillation swings so wide of the balance point that the system can no longer compensate for it.,In such an oscillation system,danger exists that the whole system may break down completely when a movement swings too far out of balance,thus making the self-correction of the system impossible.,Oscillation:frequent change between two extreme amounts of limits.,波动，摇摆,Compensate:to neutralize the effect of variations,Paragraph 10 explains under wh,Paragraph 11 is devoted to the explanation why eutrophication(,水体富营养化）,leads to the collapse of an ecological cycle.,(para.11)as the thickness of the algal layer in the water increases,dies back,releasing organic debris.,Under normal circumstances,photosynthesis can reach the lower parts of the algal layer so that it can survive and thrive.But enough light is required for photosynthesis to function.As the algal layer becomes too thick,it blocks much of the light,thus reducing photosynthetic efficiency considerably.When this happens,the overgrowth of algae dies back quickly,releasing the organic remains of the dead parts of the algae.,Die back:if a plant dies back,it dies above the ground but remains alive at its roots.,Paragraph 11 is devoted to the,(para.12)the dynamic behavior of a cybernetic system for example,the frequency of its natural oscillations depends on the relative rates of its constituent steps.,A cybernetic system consists of many steps.The rates of these steps vary.This fact determines the number of times of a cybernetic systems natural oscillations,the speed with which this system responds to external changes and its overall rate of operation.As a result of a cybernetic system acts in a continuously changing way.,Constituent:one of the parts that combine to form something,（成分）,(para.12)the dynamic behavio,（,para.13)the metabolic rates of these organisms that is,the rates at which they use nutrients,consume oxygen,or produce waste are inversely related to their size.,Metabolism includes various steps such as taking nutrients,consuming oxygen or producing waste.The speeds of metabolism of organisms differ according to the size of the organisms.The larger the size of the organism,the slower the rate.,Inversely:opposite in nature or effect or relation to another quantity;,(para.14)If the entire cyclical system is to remain in balance,the overall rate of turnover must be governed by the slowest stepin this case,the growth and metabolism of the fish.,In order to maintain the balance in the whole system cycle,the overall rate of growth and metabolism must be controlled and regulated by the slowest step.In the case of the water ecosystem cycle,this is governed by the growth and metabolism of the fish.,Turnover:the continuous process of loss and replacement of a constituent(as a cell or tissue)of a living system.,（para.13)the metabolic rates,(para.16)most ecosystems are so complex that the cycles are not simply circular paths,but are crisscrossed with branches to form a network or a fabric of interconnections.,Most ecosystems are complex.In these ecosystems,the cycles are not circular paths isolated from others,but overlapped and intersected with subdivisions so that the ecosystem is made up of a network or texture of interconnection.,Fabric:texture;quality;underlying structure;framework,Crisscross:to make a pattern of straight lines that cross each other (,构成交叉线）,(para.16)most ecosystems are,(,para.17)the feedback characteristics of ecosystems result in amplification and intensification processes of considerable magnitude.,The interrelationships within an ecosystem can result in great increases in the processes that take place within that system.In other words,ecological processes involves chains of interactions that may turn small factors into larger ones.,Amplification:making something larger or greater(as in amount,importance,or intensity).,(para.17)if the concentration of DDT(a highly effective pesticide with many dangerous side effects),which is not readily metabolized,in the soil is 1 unit,earthworms living in the soil will achieve a concentration of from 10 to 40 units,and in woodcocks feeding on the earthworms the DDT level will rise to about 200 units.,If the soil contains a certain amount of DDT,which is toxic and is therefore not used for energy,but is stored and passed on up the food chain,then the earthworms will have 200 times as much.In other words,DDT is not easily converted to energy so it tends to increasing concentration in the bodies of animals higher up in the food chain.If there is one unit of DDT in the soil,earthworms feeding in the soil will concentrate from 10 to 40 units,and in birds like woodcocks that feed on the earthworms the DDT level will rise to about 200 units.,Concentration:the strength of a solution;number of molecules of a substance in a given volume,浓度,(para.17)the feedback charac,(para.18)All this results from a simple fact about ecosystems.,After all the explanations,the writer arrives at the conclusion that everything is connected to everything else.,(para.18)a small perturbation in one place may have large,distant long-delayed effects.,The ecological network makes effects larger and greater so that a small disturbance in one place may have large and far-reaching effects.,Perturbation:,（,formal),a small change in the movement.,摄动，微扰,高级英语(第三版)第二册第十一课-Four-Laws-of-Ecology-Part-I)课件,The Second Law of Ecology:Everything Must Go Somewhere,(Paras 19-21),(para.20)Consider,for example,the fate of a household item which contains mercury(,水银）,a substance with environmental effects that have just surfaced.,Lets examine whats going to happen to a household item which contains mercury.This paragraph illustrates the law that matter is indestructible by the example of the flow of a household item.,Surface:to become known after being hidden,.,Here it is acted on by bacterial which convert it to methyl mercury(,甲基汞）,.,At the bottom of the lake,it is processed by bacteria which turn it into methyl mercury.,The Second Law of Ecology:Eve,(Para.21)It is also an excellent way to counteract the prevalent notion that something which is regarded as useless simply“goes away”when it is discarded.,This law also successfully refutes the commonly held notion that something that is regarded as useless simply disappears when thrown away.,Counteract:to reduce or prevent the bad effect of something,by doing something that has the opposite effect.,抵抗，对抗,(para.21)It is simply transferred from place to place in which it becomes,for a time,lodged.,This tells us that the trash or sewage we dump does not disappear,but is simply carried from one place to another,turned from one form of matter to another,producing an impact on the life processes of any organism in which it is stuck for a time.,(Para.21)It is also an excel,Writing Styles,The text is a combination of precise scientific writing and vivid language.,The present tense used in its explanatory language shows a style of objectivity and simplicity.,The author employs a unified logical structural style which first provides a topic sentence,usually definition,then analogy or examples to explain the topic sentence.,Each definition is followed by abundant examples.,Metaphor is frequently used in this text.Metaphor transfers unfamiliar concepts to familiar images so that readers can understand bette