<tt id="6hsgl"><pre id="6hsgl"><pre id="6hsgl"></pre></pre></tt>
          <nav id="6hsgl"><th id="6hsgl"></th></nav>
          国产免费网站看v片元遮挡,一亚洲一区二区中文字幕,波多野结衣一区二区免费视频,天天色综网,久久综合给合久久狠狠狠,男人的天堂av一二三区,午夜福利看片在线观看,亚洲中文字幕在线无码一区二区
           
            .contact us |.about us

          Highlights ... ...
          Search:
              Advertisement
          Water resources
          ( 2003-08-24 15:32)

          Ningxia is the region, which has limited water resource even though there are rainfall, surface water or underground water. As to the water resource distribution, it is quite uneven between northern and southern parts. The total amount of water resources of Ningxia is 1.05 billion m3 (excluding repeated estimation). Among them: the surface water is 889 million m3, and the groundwater is 2.657 billion m3 (including the repeated estimation). Besides, the runoff of the Yellow River in Ningxia is 32.5 billion m3, and 4.0 billion m3 can be utilized. Theoretical hydro-energy is 1.955 million kW. The distribution of the water resources is uneven. Most of them are distributed in the north, i.e. the Yellow River irrigated area. The shortage of water reserve in the central highland and hilly area make the drought the most severe problem in the whole Region. Most of them are of salted water lying deep underground. It is hardly worth using for irrigation. In the semi-droughty and semi-wet mountainous area in the south, the river network has a moderate coverage. There are Qingshi River, Kushui River, Hulu River, Jing River and Zuli River. Although there are plentiful water reserves, only small proportion can be used..

          Surface water resource

          The annual average runoff of the surface water is 889 million m3 (the runoff of the Yellow River major stream excluded). The runoff of the Yellow River is 32.5 billion m3. These two together is of a favorable condition for agricultural production. As early as 2,000 years ago (during the Qin and Han dynasty), people began to draw water from the Yellow River for irrigation. An area called "Hetao irrigated area" was formed then. In this area, there are irrigating channels as Tanglai Qu canal, Hanyan Qu, Qin Qu, Han Qu, Huinong Qu, and Xigan Qu, total 14 major canals. Their total length is 1397 km and has the capacity of 744 m3/s in flow, about 7 million m3 per year. Its irrigated area add up to as large as 275,000 ha.

          Underground Water Resource

          The amount of underground water resource is about 2.657 billion m3. But itsdistribution is quite uneven. The south and plains of north possess much more ground water than the loess hilly area. For example, Yinchuan and Weining plain occupy only 13% of the total area of the whole Region, but it has 63.85% of the total underground water reserves. The loess hilly land of Lingwu and Yanchi occupy 69% of the total area, but their ground water is only 16.2%.

          Hydro Power

          Theoretical reserves of hydro energy in Ningxia are 1.955 million kW. Among these, Erlonghe River major stream accounts for 1.9297 million kW, about 98.7% of the total. The branches of the Yellow River have 253,000 kW, only 1.3% of the total. Most of the water power resources are concentrated in the valleys of The Yellow River major stream, while some are located at the east side of Liupanshan Mountain. There are places that have the possibility to use the hydraulic power. The estimated installed capacity is 1.974 million kW. The ensured capacity is 752,000 kW. The total sum of energy obtained per year can reach 8.04 billion kWh. There are three places with an installed capacity over 10,000 kW. All of them are located on the Yellow River major stream, i.e. Daliushu, Shapotou and Qingtongxia. The Daliushu hydro power station has a capacity of 1.6 million kWh, 7.2 billion kWh per year. There are nine places having an installed capacity of 5,000 ~ 10,000 kW. Among them, eight are located at the Jing River system, and one is located at Qixing Qu of Zhongning County.

             
          Close  
            Go to Another Section  
               
           
           
               
            Article Tools  
               
            E-Mail This Article
          Print Friendly Format
           
               
             
                  .contact us |.about us
            Copyright By chinadaily.com.cn. All rights reserved  
          主站蜘蛛池模板: 精品人妻中文av一区二区三区| 女同久久精品国产99国产精品| av无码小缝喷白浆在线观看| 特级欧美AAAAAAA免费观看| 自偷自拍三级全三级视频| 在线看国产精品自拍内射| 欧美午夜理伦三级在线观看| 少女大人免费观看高清电视剧韩剧| 日韩精品中文字幕有码| 黄色av免费在线上看| 亚洲国产成人午夜在线一区| 97色伦97色伦国产| 日韩AV高清在线看片| 国产在线观看免费人成视频 | 性做久久久久久久久| 欧美日韩一区二区综合| 豆国产96在线 | 亚洲| 免费 黄 色 人成 视频 在 线 | 99久久久无码国产麻豆| 久久不见久久见免费视频观看| 国产二区三区不卡免费| 国产成人综合在线女婷五月99播放| 国产精品hd在线播放| 午夜福利国产精品视频| 亚洲国产天堂久久国产91| 亚洲综合av男人的天堂| 亚洲综合精品第一页| 免费国产好深啊好涨好硬视频 | 国产极品美女网站在线观看| 久久天天躁狠狠躁夜夜躁2o2o| AV区无码字幕中文色| 手机看片日韩国产毛片| 国产999久久高清免费观看| 免费播放一区二区三区成片| 亚洲国产一区二区三区久| 成年黄页网站大全免费无码| 日本公与丰满熄| 最新国产色视频在线播放| 日本高清视频网站www| 亚洲无av在线中文字幕| 尤物视频色版在线观看|