三峡水利枢纽的建设意义

Three gorges water conservancy hub
The dam is located in the Yangtze river mainstream,yichang and their downstream and not far from the gezhouba hydropower station of cascade hydropower station form scheduling.It is the world's largest hydropower station,the construction of Chinese history is the most large engineering projects.
Dam,185 meters high,the total capacity of 39.3 billion cubic meters,including flood control capacity of 22.15 billion cubic meters.
The three gorges water control project has a "for the storage,can compensate for" the unique function of the three gorges project,the flood control,power generation,navigation,moisturizing and comprehensive benefit overall play began.
After the completion of the three gorges dam,will form the enormous reservoir,sluggish water,and downstream lower jingjiang river flood of flood control ability,the dam defense ten years of the worst flooding,rising to resist the worst flooding in years the flood,the capacity of the flood control in 73-22 billion cubic meters between.The most significant benefits of flood control the water conservancy project.In case of the flood,which can effectively defense.
Xiaolangdi project
There is the only can make great sanmenxia reservoir dam site.Xiaolangdi reservoir therefore become a defense of the lower Yellow River catastrophic floods of important engineering.Effective control of the Yellow River floods,can make the lower Yellow River,the flood control standard HuaYuanKou by 60 years once QianNianYiYu to improve.The Yellow River xiaolangdi project on the Yellow River basin is a collection of sedimentation reduction,flood control,water supply,irrigation,power generation FangLing,is a large comprehensive water conservancy project.
At present our country seven big rivers,from the valley speaking,can the biggest since the establishment of the defense.Especially in 1998 after the floods the Yangtze river,the central increased investment in water conservancy construction.According to statistics,1998 to now,the investment is 285.8 billion yuan,used for flood control of the engineering construction investment is 173.4 billion yuan.
According to statistics,by now the country has built more than 86000 seats,all kinds of reservoir dyke 286900 kilometers long,the large rivers in our country has basically met the main reach the defense since the founding of the worst flooding ability,medium and small rivers have defense of the flood protection ability,general population of 570 million,protect arable land 46000 hectares.The national 639 seats have the task of flood control large,medium and small cities,there are 299 buildings through the flood control engineering construction to fortify standards.Water conservancy project continuously strengthen infrastructure system,big rivers and lakes,the water conservancy and flood control status great improvement of people's life and property security role in economic and social development and further enhance the support ability.

（1）水对库底的压强为：p=ρgh=1.0×10³kg/m³×10N/kg×156m=1.56×10⁶Pa；
（2）船闸的工作原理是连通器原理，船通过船闸时，使用了两次连通器；
（3）水飞速流下时，周围空气流速加快，压强减小，在外面大气压的作用下，水很难马上散开．
故答案是：（1）1.56×10⁶；（2）连通器原理；（3）水飞速流下使附近空气流速增大，压强减少．

不可以
三峡水电站只是长江三峡水利枢纽工程的附属部分,甚至不是主要部分
长江三峡水利枢纽工程主要目的是
1.防洪抗旱,水多的时候将水存起来,少的时候将水放出来,在千年一遇的旱灾或洪水时,保证流域地区不会大旱或大涝
2.通航,万吨级船只可以直接从外海航行到重庆,使西部地区有外向型及出口经济便利很多
3.发电,解决长江中下游地区的用电问题

在湖北省宜昌市.葛洲坝水利枢纽在宜昌市三三0-----（西坝）,三峡水利枢纽在宜昌市三斗坪.

A防洪 是兴建三峡工程的首要出发点

解题思路：长江发源于青藏高原的唐古拉山，在上海市注入东海．黄河发源于青藏高原的巴颜喀拉山，曲折东流入渤海．水电站建在阶梯交界处，落差大，水能资源丰富．

三峡水利枢纽位于长江的上游，地处渝鄂两省及二、三阶梯交界处；小浪底水利枢纽位于黄河的中游，地处河南省境内，二、三阶梯交界处．故选项D符合题意；选项A、C、B不符合题意．
故选：D．

点评：
本题考点： 葛洲坝水利枢纽与三峡水利枢纽工程的位置．

考点点评： 在长江流域水系图和黄河流域水系图上，明确三峡和小浪底的位置，结合上中下游的分界点、省区及阶梯分界线解答该题．

D.在地势的第二,三级阶梯交界处

解题思路：长江发源于青藏高原的唐古拉山，在上海市注入东海．黄河发源于青藏高原的巴颜喀拉山，曲折东流入渤海．水电站建在阶梯交界处，落差大，水能资源丰富．

三峡水利枢纽位于长江的上游，地处渝鄂两省及二、三阶梯交界处；小浪底水利枢纽位于黄河的中游，地处河南省境内，二、三阶梯交界处．故选项D符合题意；选项A、C、B不符合题意．
故选：D．

点评：
本题考点： 葛洲坝水利枢纽与三峡水利枢纽工程的位置．

考点点评： 在长江流域水系图和黄河流域水系图上，明确三峡和小浪底的位置，结合上中下游的分界点、省区及阶梯分界线解答该题．