三峡大坝介绍英文.pptx

Geography Case Study -Chang JiangCons and Pros of the Three Gorges ProjectIntroductionnChinas massive Three Gorges hydroelectric project has generated plenty of controversy from the start.It was first proposed in 1919 by revolutionary leader Sun Yat-sen as a way of providing energy to fuel the nations industrial development.The plan was revived in 1954 as a way to control the chronic overflow of the legendary Yangtze river after tens of thousands were killed in widespread flooding.After several false starts,work began in earnest in 1979.nAdvocates say Chinas development depends on it.They say it will provide a clean source of energy for future generations.But critics say it could be a monumental ecological disaster.nThe dams sluice gates were closed on June 1,2003,allowing the reservoir behind it to begin filling.By June 10,2003,the water was 135 metres deep,and its expected to be 175 metres deep by 2009.FactsnThe 16-year project is due to be completed in 2009.nThe rivers level is expected to rise to 175 metres.nBy mid-June 2003 the dam was holding back 12 billion cubic metres of water.The dams storage capacity is nearly 40 billion cubic metres.nIt will create a 658-sq.-km reservoir.nIts concrete wall is 192 metres high.nIt has a total of 22 sluice gates.nIt will have 26 700-megawatt turbine generators.They are expected to produce 18.2 million kilowatts by 2009.Eleven of the reactors were in place as of January 2005.nIt has the worlds largest lock system,6?kilometres in length.The lock lifts and lowers ships in five stages.nThe dam is located in Yichang,in the central province of Hubei.nIts Chinas biggest engineering project since the Great Wall was built more than 2,000 years ago.nTotal projected cost:180 billion yuan($26.5 billion).Location of SanxianA man fishes as water flows through water diversion holes of the Three Gorges Dam on the Yangtze River in central Chinas Hubei Province,June 11,2003.Some 10 water diversion holes were opened to release water.The water level of the Three Gorges Reservoir reached 135 metres(433 feet)on June 10.(AP Photo/Xinhua,Du Huaju)nTwo men carry bricks to a barge at the temporary dock at Wushan,in the middle of the Three Gorges on the Yangtze River in central China,June 6,2003.Lower lying areas of the town have been demolished in preparation for the increase in the water level as the controversial Three Gorges Dam reservoir begins to fill.(AP Photo/Greg Baker)nA Chinese man sits in the rubble of the demolished old town of Wushan,as he looks out over the citys temporary dock on the Yangtze River in central China,June 6,2003.(AP Photo/Greg BakernWorkers build a stone embankment as water from the Yangtze River rise up the shoreline at the newly built town of Fengjie,in central Chinas Chongqing municipality,June 9,2003.The old town of Fengjie was demolished because it was below the high water mark of the reservoir of the Three Gorges Dam.(AP Photo/Greg Baker)nThree young boys watch as rising waters inundate a corn field at Qutang Village,near Fengjie,in central Chinas Chongqing municipality,June 9,2003.Water levels have been rising between two and four metres each day since China began filling the reservoir.Despite warnings from local officials that waters would rise in June,many farmers planted crops because they were unsure of where the high water mark was on their land,while others did not believe that waters could rise so high.(AP Photo/Greg Baker)nShips sail through the Xiling Gorge of the Three Gorges on the Yangtze River in central China,June 11,2003.The water level of the Three Gorges Reservoir reached 135 metres(433 feet)June 10,five days ahead of the schedule.(AP Photo/Xinhua,Cheng Min)nThe aerial photo,taken on June 3,2003,shows the Three Gorges Reservoir on the middle reaches of the Yangtze River at Yichang,Hubei province.The water level reached,as planned,114.29 metres high on the sluice gate.(AP Photo Xinhua,Cheng Min)nHydroelectric generating sets of the Three Gorges Project in central Chinas Hubei Province are shown in this April 9,2003 photo.Four of the hydroelectric generating sets,which are in the final phase of installation and test,will be put into operation later this year.(AP Photo/Xinhua,Du Huaju)nWater flows through water diversion holes at the bottom of the Three Gorges dam,June 1,2003.Chinas Three Gorges Project officially began to store water as the sluice gate of the dam started to be closed as scheduled.China began filling the reservoir behind its gargantuan Three Gorges Dam in a major step toward completion of the world-largest hydroelectric project.(AP Photo/Xinhua,Cheng Min)nA man rushes to board a boat before it leaves,in Chongqing city,on the Yangtze River in central China,June 5,2003.Though more than 600 kilometres(372 miles)from the Three Gorges Dam,water levels at Chongqing will rise up to 15 metres when the dams reservoir is filled to its highest level on completion in 2009.(AP Photo/Greg Baker)PROSFlood controlThe reservoirs 22 km(28.9 billion cubic yard)flood storage capacity will lessen the frequencyof big downstream floods from once every 10years to once every 100 years.It protects lifeand property.NavigationThe installation of ship locks are intended to increase river shipping from 10 million to 50million tons annually,with transportation costs cut by 30 to 37 percent.Cheap andconvenient river transport will be provided.Also,shipping will become safer,since the gorgeshave lower flowing speed of channel.AgricultureThe reservoir stores up the water that can bediverted to irrigate farmland.It increases cropproduction and exports of surplus farm produce,e.g.citrus fruits.Energy and EnvironmentlThe dam will generate 18,200 megawatts of Hydroelectric power,the equivalent of 18 nuclear powerplants.It will facilitate industrial and economicdevelopment.lChina now relies on coal for of its electricity.Its airis among the foulest in the world and contributes toglobal warming.Hydro-electric power is arenewable energy source that does not generatewaste.It improves air pollution.Water SupplyDams can store rain water or water directlyfrom the river itself.Then,in case of a drought,the dam will still have a relatively constantsupply of water.ResettlementIn 1996,floods displaced more than one millionpeople from their homes.Besides,180 millionpeople are now without electricity in China.But 15 million people downstream will be betteroff due to the control of flood and the supply ofcheap electricity.Also,population distribution tonewly-opened area,e.g.higher ground of thedam,will be present.Recreation and TourismThe project provides recreational activities suchas boating fishing and swimming,if the lake isnot being used for drinking water.Also,cruiseships will be able to sail at all time.Thus,thedam will serve as a new tourist spot.ReputationThe Three Gorges will be the most powerfuldam ever built.This is an important politicalstatus symbol for China.CONSResettlement nAbout 1.3 million people will eventually be relocated from 1,400 villages in the area.By June 2003,720,000 people,from farmers to fishermen,had been displaced.In addition to the hardship of resettlement,critics say people are being moved to far less fertile land.Pollution nThe resettled people have left dozens of deserted towns in their wake.The buildings include hospitals and abandoned industrial sites.Environmentalists say refuse from those sites will seep out and contaminate the water.Ecology/Archeology nClimate experts say the humidity and temperature will increase around the dam,causing unknown impact to the ecosystem.The Yangtze basin supports fish,wild fowl and plants,some of which are endangered.The area slated to be submerged is famous for its breathtaking scenery and is home to archeological sites including burial grounds and ancient temples.Efficiency nCritics say a series of smaller dams would have fulfilled the countrys energy needs with less impact on the environment.Corruption nThe project has been plagued by charges of nepotism and inefficiency.After a number of high-profile accidents,the government ordered much of the infrastructure replaced in 1999.nConcerns have surfaced about the dam itself.There are some facts to prove.Firstly,allegations of corruption among officials involved with the project have raised fears of shoddy construction.The Chinese media recently reported several incidents in which corruption and poor construction have led to disasters at major building projects.Notable among the reports was the collapse of a steel bridge in the city of Chongqing in January 1999 that killed 40 people.nSuch incidents also have prompted rare open criticism from the Chinese leadership regarding the Three Gorges Dam.In early 1999 Chinese Premier Zhu Rongji inspected the dam site.He warned those involved in the project that the responsibility on your shoulders is heavier than a mountain.Any carelessness or negligence will bring disaster to our future generations and cause irretrievable losses.Zhu also suggested China might invite top international engineers to inspect the dam and monitor its construction.Chinese leaders have long dreamed of taming the Yangzi for power generation and flood control.The rivers infamous floods have brought destruction and death for centuries-1 million deaths in the 20th century alone nDai calls Three Gorges the most environmentally and socially destructive project in the world.She also calls for a halt to construction and supports the idea of a series of smaller,less disruptive construction projects on tributaries of the Yangzi.nMoreover,of further concern are claims the dam might become an environmental disaster.There have been little to no attempts made toward removing accumulations of toxic materials and other potential pollutants from industrial sites that will be inundated.Experts say such materials could leach into the reservoir,creating a health hazard.Besides,the relative lack of waste treatment plants in China also could mean run-off from communities around the dam would most likely go untreated directly into the reservoir and into the Yangzi.nBy severing the mighty river and slowing the flow of its water,the dam will cause pollution from industrial and residential sources to concentrate in the river,rather than be flushed out at sea,writes Chinese journalist Jin Hui in The River Dragon Has Come!a recently published collection of criticisms against the dam.The result will be a poisoned river.Electrical power derived from the dams turbines will provide up to one-ninth of Chinas output,the government estimates nNot only these,there are also claims that the dam will actually contribute to the silt accumulation in the Yangzi,rather than allow larger ships to travel the river.nAnd others dispute whether the electricity generated by the dam will be efficiently used.nIn terms of an American scale,this dam is somewhat akin to the electrical load between Philadelphia and Washington D.C.being served from a single power plant.nByrne is skeptical whether the huge amount of electricity expected to be generated by the Three Gorges project-meant to produce power for Chongqing and places as far away as Shanghai-can be efficiently and economically absorbed by Chinas electrical system.nThe social element of Three Gorges has generated more questions than answers.The dam will drown more than 100 towns once the water starts to rise in 2003.Government estimates say 1.2 million people will be resettled and that new land is being provided for 300,000 farmers.Some observers say the government may be underestimating by as many as 700,000 the number of people who actually will be relocated.The Three Gorges Dam project will require the resettlement of 1.2 million people,according to the government,although observers say that estimate may be short by as many as 700,000 people nThe issue of the farmland,much of which has been tilled by the same Chinese families for centuries and will be lost under the reservoirs waters,is particularly important,Byrne says.nOne of the tragedies of this project,if just from a regional standpoint,is that the land that is going to be flooded is some of the most fertile in China,says Byrne.The land to where the population is to be relocated is much less fertile.nHistorians also have questioned the dams impact on attempts to preserve some aspects of Chinas long and illustrious history.Archaeologists and historians have estimated nearly 1,300 important sites will disappear under the reservoirs waters.nMost irreplaceable,according to some experts,are sites that are remnants of the homeland of the Ba,an ancient people who settled in the region about 4,000 years ago.A former curator at Beijings National Museum of Chinese History describes the area as the last and best place to study Ba culture.nFor its part,the government is well aware of the problems and challenges posed by the Three Gorges project.Nevertheless Guo Shuyan,deputy director of the Three Gorges Project Commission under the State Council,has described the project as environmentally sound,on the whole.The Yangzi is the longest river in Asia and the third longest in the world,stretching nearly 4,000 miles across China.The worlds longest river is the Nile;the second longest is the Amazon nChinese officials note the dam may end up providing as much as one-ninth of the nations electrical production.Considering that China burns 50 million tons of coal each year for energy,their point is that the environmental benefits outweigh the environmental damage.nIt appears the Three Gorges project is too far along to be halted.More than 20,000 workers are working around the clock on the dam itself.The reservoir is expected to be at its full depth by 2009.MapsVideosGROUP MEMBERS:nCheong Yau Kit(Kit)nKan Cham Chung(Kenneth)nLuk Kwai Lung(Ryan)nLau Ka Ho(Max)THE ENDThank you for your attention