第一册Unit9Savingtheearth正式版课件

Click to edit Master title style,Click to edit Master text styles,Second level,Third level,Fourth level,Fifth level,11/7/2009,#,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,*,第一册Unit9Savingtheearth正式版课件,第一册Unit9Savingtheearth正式版课件,Buddhist Cave Art In Dunhuang,Desert near the Dunhuang Cave,What beautiful pictures,but what a terrible scene in the future if we do nothing to stop it!,Buddhist Cave Art In Dunhuang,第一册Unit9Savingtheearth正式版课件,These satellite images show the same section of a Brazilian rain forest found along the Amazon river taken in 1975,left,1986,center,and 1992,right,.Over a 17-year period,among the human activities leading to this widespread deforestation are commercial logging,agriculture,mining,and oil exploration as well as small-scale activities,such as slash-and-burn agriculture,charcoal production,and firewood collection.Fire is used as the primary means to clear forests for agriculture and development,a dangerous method that frequently escapes control and destroys large areas of forest.,Satellite Images of Deforestation,These satellite images show th,Clear-cut Forest,Malaysia,Logging is an important industry in many parts of Asia,particularly in Southeast Asia.However,there is growing concern about the environmental effects of deforestation,caused by clear-cutting trees from large tracts of land.This rain forest was cleared in Sabah state in Malaysia,.,Clear-cut Forest,Mal,Industrial Smokestacks,Carbon dioxide,(,二氧化碳硫,),sulfur dioxide,(二氧化硫),and other types of contaminants pouring from industrial smokestacks(烟囱)contribute largely to the worlds atmospheric pollution.Carbon dioxide contributes significantly to global warming,while sulfur dioxide emissions are the principal cause of acid rain in the northeastern United States,southeastern Canada,and eastern Europe.,Industrial Smokestacks C,Traffic Pollution,Gas sent out by cars contains unburned hydrocarbons(碳氢),particulates(微粒),carbon dioxide(二氧化碳),and oxides of nitrogen(氮化合物)and sulfur(硫)that contribute to acid rain,smog,global warming and the cause of the greenhouse effect,a phenomenon thought to be responsible for rising global temperatures.,Traffic Pollution Gas sent ou,From air to water,exhaust=send out,atmospheric moisture 水气 sulfurous 硫,nitric氮,carbonic 碳,acid 酸性物,sparse foliage 稀少的树叶,photosynthesis 光合作用,ecosystem 生态系统,organism 有机物,From air to waterexhaust,On April 26,1986,one of the nuclear reactors at the Chernobyl nuclear power plant in Ukraine went off,sending out about 100 to 150 million curies(,居里,)of radiation into the atmosphere.In the following weeks,clean-up people worked to control the damage and reduce emissions(,放射,)from the radioactive debris(,放射性残骸,).,Chernobyl Decontamination Effort,（切尔络贝利的清污行动）,On April 26,1986,one of the,The Bhopal Disaster,On the night of Dec.23,1984,40 tons of deadly poisonous gases began leaking from Union Carbide Corporations pesticide factory in Bhopal,India.Nobody outside the factory was warned.,Over,20,000 died and today more than 120,000 people are still in need of urgent medical attention.,The Bhopal DisasterOn the nigh,Polluted River in the United Kingdom,The pollution of rivers and streams with chemical wastes has become one of the most serious environmental problems of the 21th century.Chemical pollution entering rivers and streams comes from factories,outfall pipes,or from runoff from agricultural or mining operations.Its said that each year around 10 million people die worldwide from drinking polluted water.,Polluted River in the United K,Industrial water pollution,Industrial water pollution,the Mediterranean Sea,The Suez Canal,Strait of Gibraltar,the Mediterranean Sea Th,Black Forest in Germany,The Black Forest is a wooded mountain region located in southwestern Germany.Its name derives from the large stands of fir trees that are found on its upper slopes.Although the area is a favorite spot for recreational activities such as hiking,air pollution has caused major problems.It is estimated that more than half the trees in the Black Forest have been damaged as a result of acid rain.,Black Forest in G,Lake Baikal in Russia,Lake Baikal is the deepest freshwater lake in the world and the third largest lake in Asia.A large variety of plant and animal life is found in its clear waters.Many rivers,as well as more than 300 mountain streams,feed into the lake.,Lake Baikal in,Exxon Valdez,Oil Spill in Alaska,1989,Workers wash the shoreline on Latouche Island,Alaska,after the,Exxon Valdez,oil tanker ran aground in 1989,dumping more than 38 million liters(more than 10 million gallons)of oil into Prince William Sound.,Exxon Valdez Oil Spill in Alas,Waste water treatment,Waste water treatment,Pest control or pollution?,Pest control or pollution?,Sound intensities 声音的强度,Sound intensities 声音的强度,The,Plateosaurus,the largest dinosaur of its day(about 231 million to 213 million years before present,The Plateosaurus,the largest,The,Velociraptor,was a medium-sized carnivorous dinosaur that lived in Asia a