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离线 紫露草

楼主 发表于2010-11-06 17:28

Keep Healthy Life of Rivers—A Case Study of the Yellow River

Keep Healthy Life of Rivers—A Case Study of the Yellow River

Li Guoying

(Yellow River Conservancy Commission)



Abstract: The paper states the interrelation between rivers and development of human civilization, fully demonstrates the rules of rivers on development of human civilization, natural environment, social and economic development, discusses the concept that the development of human civilization and river’s life relies on and influences each other. Through the discussion on river’s life, the concept of river being the subject of value is established, and the final objective of river management, keeping healthy life of rivers, is put forward. Regarding Yellow River management and development, a river management strategy on keeping healthy life of the Yellow River in the new era has been established, and the connotation, objectives and strategies of the completely new concept is demonstrated from different perspective of theoretical system, engineering system and ethical system. It is to build a harmonious relationship between human being and rivers, and finally refresh and maintain healthy life of the Yellow River, by administrative, legal, technological, engineering and economic measures and through the implementation of 1493 project.

Keywords: river life, healthy life of the Yellow River, river management system



1 The concept of river life and the ultimate aim of river training

1.1 rivers gave birth to human civilizations

Any life phenomenon on earth is closely related to water and life cannot evolve without water. It is true that rivers gave birth to human civilization if it is true that water gave birth to life. It relied on rivers that human beings developed from nomadic stage to working at agricultural production, and then created irrigation civilization.

The Nile River met the basic needs of the survival and producing of ancient Egyptian with its unique natural condition, which greatly promoted the development of the society economy of ancient Egypt. Ancient civilization came into being in the flood year by year of the Nile River.

The melted water and rain in the upper reaches of the Euphrates River and the Tigris River moistened the dry land in the lower reaches, which gave birth to Sumer irrigation civilization and the prosperity of ancient Babylon Kingdom.

The topographic condition and climate, hydrologic condition of the Indus basin precipitated the bronze civilization in the subcontinent of South Asia.

The Yellow River fostered the growing of Chinese nations and promoted the springing up and developing of agriculture and other economic activities with its life water.

The human history of civilizations created by Ancient Egypt, ancient Babylon, ancient India and ancient China are in fact the history of the Nile River, the Euphrates River and the Tigris River, the Indus River and the Yellow River, which the civilizations’ existing and developing relied on.

It is proved by history that human civilization cannot come into being, not to mention development without rivers. Therefore, rivers are the origin of human civilization. They not only gave birth to human civilization but also moistened the growing of human civilization.

1.2 Harm done by human to rivers and its aftereffects

Rivers play an important part in the gestation and development of human civilization. While developing rivers, human beings should set up a supreme noble biological conscience, biological ethics and biological duties and consider them as ethics and code of conduct.

However, it is not the case when we read through the relationship history of human beings and rivers at home and abroad. Even today, due to the limit of cognition level or the local benefits, the mankind-centered is still the direction. We pay little attention to the rivers’ carrying capacity so that the life rivers that mankind depends on existing suffer calamity repeatedly.

In 77 A.D., the ancient Loulan Kingdom along the Peacock River is the oasis on which agriculture is the most developed in the Western Regions. The excessive developing on the Peacock River resulted in its drying up. In 542 A.D., ancient Loulan Kingdom died out on earth. Loulan Kingdom that had been once in fashion for a period was buried in the desert on the western bank of Luobubo Lake.

The Tarim River is the longest inland river in China. It is closely related to the existing and developing of the Tarim basin because it is the only water-transporting passage for maintaining the ecosystem of the eastern Tarim basin and also the natural barrier obstructing Taklamakan desert and Kum-tagh desert. But owing to the excessive developing and utilization of water resources, the lower river course has been under the condition of running dry for quite a long period since 1970s, which made the strategic Green Corridor in its lower reaches on the edge of destroying. Taklamakan desert and Kum-tagh desert divided by the Green Corridor is potentially to be connected.

The Huaihe River Basin is a basin in which the population is the densest of China. Since 1980s, the large water-utilizing and serious-polluting industries in the basin have developed rapidly such as paper making, brewage, chemical industry, leather, electroplate, etc. The discharge of waste water and polluted water increased quickly. At the same time, the pollutant remainder from the fertilizer and pesticide used on crops went into the branches and mainstream of the Huaihe River. The Huaihe River becomes a big sewage ditch, which is worthy of the name. The ecosystem along the river is threatened severely.

The Amu Darya River is the longest river in Central Asia and the main source of the Aral Sea. Developing of the irrigating area in the upper and middle reaches resulted in a large quantity of water was diverted away before running into the Aral Sea and the water in the Aral Sea decreased sharply. In the end of 1980s, the Amu Darya River running dry occurred. During 1960-1990, the water level of the Aral Sea dropped 14.9 m, the area shrank 42.5%, and the storage decreased 69.5%. The area of dry lake bottom reached 270 thousand km2, among which 90% became desert and the area of salt and pesticide deposition. The gale blew up about 40,000 ton salty soil from the dry bottom of the lake each year. The holding poisonous content can reach 400-800km, which causes the sharp increasing of aspiratory system diseases and cancers of human beings and livestock in the leeward.

The Colorado River is the longest river in the southwestern dry area of the U.S. The excessive development of water resources made flood process in natural condition not appears any more, river course shrank, wetland in the lower reaches decreased greatly, and water quality in the estuary deteriorated[1]. Additionally, some poisonous and radioactive matters go into the river through underground water. Rivers Association of the U.S has put it on the first of the top ten rivers in 2004 which are in severe danger[2].

The water resources utilization of the Yellow River has broken the utmost of the river carrying capacity. It is indicated that in the 28 years from 1972-1999, the river running dry occurred in 21 year. In some years, river’s running dry occurred many times, which severely affects the life and agricultural and industrial production of the people of the cities and villages along the river in the lower reaches and destroys the ecosystem of the estuary delta.

The Yellow River is a sediment-laden river. Flood advantageous to scour the riverbed of the lower reaches did not occur in the last 20 years. The main channel deposits more. The discharge that the water level is as high as the floodplain falls greatly. The situation of “secondary suspended river” is severe. The main channel is hard to hold even small flood. River regime changing would happen once the small flood runs out of the main channel. Meanwhile, the waste and polluted water that coming into the Yellow River increased from 2.17 billion t/year to 4.15 billion t/year in recent 20 years, among which most of them goes into the branches or mainstream of the river directly without processing. The ratio of polluted water and runoff becomes bigger and the contradiction of water supply and need sharpened.

With the development of the economic society and demand from the river, most of the rivers in the modern world are under the condition of “morbidity”. Some have been “beyond cure”.

1.3 The foundation of the concept of river life

In the traditional or narrow sense life science, biologists normally thought that river has no life although river is rich of life variety on earth and plays an important part in the biology circle. Life, as a general scientific conception, was defined in 19 century, which is used to distinguish biology from non-biology. Traditional or narrow sense life conception is defined based on biological features.

According to the big trend of modern natural science development and the background of rapid life science development in 20 century, broad sense life science study will go into ecosystem, that is, the integrated study combined natural science with sociological science would be carried out and further developed to the systematized direction, regarding mankind as the principal part, considering the integrated effects of ecology, economy, society and institution and on the basis of the combination of theory and control strategy study.

In modern broad life science, the penman suggests that to endow river with life and set up the conception of river life.

1.3.1 In macro scale, river embodies completely the change, harmony and unification of substance, energy and information in the process of life movement.

The life movement process has three foundational functions: energy flow, substances recycle and information transfer, among which energy flow and substance recycle are the main features in ecosystem. The hydrologic recycle centering on river has the obvious features of energy flow and substance recycle.

Hydrologic recycle is the most important recycle of substance on earth, which plays a very important role in the formation and evolvement of global environment and the existence of human beings. Water exchange and renewing among water bodies are realized in water circle through hydrologic recycle. Hydrologic recycle affects the climate feature of an area, makes water an important geological construction force to realize the chemical substance transfer on earth. In the hydrologic recycle, rivers are in the center all the time. On the one hand, rivers receive rain water directly; on the other hand, rivers take up the gathering of underground water and undercurrent, at the same time, act as waterway to transport the rain, coming-out underground water and undercurrent to sea or lake in the lower reaches.

The radiation from the sun gives energy to the life movement of biology. The energy of driving the movement of hydrologic recycle comes also from the radiation of the sun. Water bodies in land and in oceans absorb the energy of the sun radiation and transfer it into potential energy, overcome G-force and vaporized into air. G-force makes vapor in air fall on land and then form runoff. One part of potential energy loses in the raining process, one part becomes the kinetic energy of flow in river and a certain potential energy remains. Under the impact of G-force, water in rivers flows from the upper reaches to lower reaches continuously. The contained water energy is used up dispersedly and gradually in overcoming flowing resistance, scouring riverbed, holding sediment, etc. As the energy movement process of ecosystem, water energy in rivers flows unilaterally according to degressive law.

1.3.2 Only when rivers are endowed with life, the status of rivers’ value can be set up, and the value tropism of mankind centering can be changed.

The values centering on human beings show that it is valuable only that it is useful to mankind. It is not valuable if it is useless to mankind. Mankind thought that he is the center and dominator of the nature and put him in the position of conquering and winning over the nature. Mankind makes his choice according to whether it is useful or not, ignoring the value of the nature and environment. As a result, ecosystem suffered havoc when traditional economic index increased obviously. The deadliness of the values centering on mankind lies in only emphasizing economic increasing and ignoring the restriction of the ecological background which economic development never break away from; economic activities are isolated; and permanent linear economy increase is attempted in this non-linear circulating ecosystem.

The values centering on mankind led to the excessive development and utilization of the rivers. The negative feedback of rivers also made human beings pay an expensive price. Experiences and lessons told us that human beings should exist in harmony with rivers. To realize this aim, rivers should be considered as life body. Only in this way can human beings’ conscience of respecting river be woken and limit a “base line” for the blindly-expending human activities.

1.4 The ultimate aim of river training

The core of river life is water and the vitals is flowing. The non-breaking runoff process in rivers indicates the pulse beating of river life. Only when the continuous runoff process exists, the ecosystem along the river would keep healthy. The timely flood process indicates that river is full of vitality and life energy. No river course shrinking will be possible and river will be kept healthy only when a certain-scaled flood process occurs timely. So it is incorrect to think that to use up the water resources in a river through a series of water projects is the achievement and symbol of high ratio of water resources utilization. It is incorrect to think that to eliminate all the floods in a river through a series of engineering measures is the main criteria of completely training of a river.

Up to now, the basic method and technical way of river training are perfected in the world. The control on rivers is almost freewheeling. It does not need to conceal the truth that people seem to pay more attention to the training process comparing to the training aim. It seems that the values of river training can only be embodied fully in the process of dynamic engineering constructions. On the contrary, the ultimate aim of river training is not discussed earnestly and sufficiently. Of course, it is hard to give one definition of ultimate aim of river training. After all, rivers in the world are individual and particular. But from river life, we can still find a common-expected answer, that is, the ultimate aim of river training is to keep healthy life of river. River’s individuality and particularity will be shown in the respective different index or framework of healthy life of each river.

2 River training system of keeping healthy life of the Yellow River

2.1 The study content of keeping healthy life of the Yellow River

2.1.1 Theoretical system

It is a brand-new conception to consider keeping healthy life of the Yellow River as the ultimate aim of the Yellow River training. There is no ready theory and experience for reference. Thereby the theoretical system of keeping the healthy life of the Yellow River should be set up. The system should include the definition, connotation, aim and control indexes of healthy life of the Yellow River, confirm the course and phases of realizing the healthy life of the Yellow River and the measures to take in each stage.

2.1.2 Producing system

If we say that the construction of theoretical system emphasizes particularly on logical strictness, preciseness of definition and grasp of the inner natural law, the construction of producing system emphasizes particularly on the carrying out of specific training scheme and the obtained object effect, or the approaching of the ultimate aim of keeping the healthy life of the Yellow River through carrying out the training scheme. Theoretical system is the precursor of producing system. Producing system relies on by theoretical system. The two supplement each other.

2.1.3 Ethic system

By making a general survey on the harm done to rivers at home and abroad, the value tropism centering on human beings is protruded. In fact, an ethic relationship did not set up between human beings and rivers so that no one believes that human beings should take on their ethic duties to rivers. A basic ethic value—river ethics should be set up if all the society change keeping healthy life of rivers into the consciousness and active action of human beings, and make it penetrate into the process of multiplying and growing of human beings. Broadly common-abided Ethics usually have more restriction force at large than national law.

2.2 The phases dividing of the process of keeping healthy life of the Yellow River

To keep healthy life of the Yellow River is an arduous and long-term historic duty. In the process of realizing the ultimate aim, three stages of short-term, middle-term and long-term would be divided according to the changing of water and sediment condition of the Yellow River.

2.2.1 Short-term stage

Short-term stage refers to before south-to-north water transfer project put into use. During this period, total quantity of sediment that comes into the Yellow River would be decreased to 0.3 billion ton through water and soil erosion control of Loess Plateau. Economic society development still keeps high need of water resources while the Yellow River does not get supplement from other rivers. The situation of the Yellow River’s less water, more sediment and inconsistent relationship of water and sediment is still deteriorating. So the short-term working aim is to keep the continuate deteriorating trend of all kinds of disadvantages for keeping healthy life of the Yellow River within limits.

2.2.2 Middle-term stage

Middle-term stage refers to after the first and second phases, but before the third phase of south-to-north water transfer project is put into use. During this period, total quantity of sediment that comes into the Yellow River would be decreased to 0.5 billion ton through water and soil erosion control of Loess Plateau. Water resources would increase 9 billion m3 through south-to-north water transfer project. Additionally, water resources demand is managed effectively. Water and sediment relationship of the Yellow River is improved. Middle-term working aim is to further improve the regulating ability of water and sediment relation, strengthen the regulating effect, restore gradually the basic function of the river course in order to effectively improve river ecosystem.

2.2.3 Long-term stage

Long-term stage refers to after the third phase of south-to-north water transfer put into use. Total quantity of sediment that comes into the Yellow River would be decreased to 0.8 billion ton through water and soil erosion control of Loess Plateau. 8 billion m3 of water will be increased on the basis of middle-term south-to-north water transfer. Water resources of the Yellow River will increase 17 billion m3. With the further reducing of sediment that comes into the Yellow River and increasing of water resources, water and sediment relationship of the Yellow River would be further improved. Meanwhile, water and sediment regulation system would be completed. Long-term working aim is to keep healthy life of the Yellow River through perfect water and sediment regulation system, and to realize the harmonious coexistence of human beings and the Yellow River.

2.3 “1493” river training system

To keep healthy life of the Yellow River is the ultimate aim of the Yellow River training. The aim embodies a river training idea. It would be shown through specific form or carrier, namely, the healthy life of the Yellow River would have a criteria. The criteria have four signs: “no embankment breaching, no river course running dry, no pollution over standard, no riverbed rising”. The four signs would be realized through corresponding training ways. The nine training ways are in the following:

(1) Reduce sediment that comes into the Yellow River

(2) Effectively manage water resource utilization of the Yellow River basin and related area

(3) Increase water resources of the Yellow River through water transfer master plans from other rivers

(4) Construct water and sediment regulation project

(5) Set up and realize a scientific and reasonable training plan for the lower reaches of the Yellow River

(6) Regulate favorable hydrological process to mitigate the shrinking of the main channel in lower reaches

(7) Take measures to protect water resources to meet the demand of water quality function

(8) Manage Yellow River delta area to reduce seawaters’ impact on the lower reaches

(9) Model the runoff process to meet the demand of keeping the ecosystem of the estuary delta virtuous

In order to ensure the nine ways’ scientific and rational, each specific scheme and measure would be put into scientific decision-making field. The field is composed of “Three Yellow Rivers”, namely, nature Yellow River, digital Yellow River and model Yellow River.

One ultimate aim, four main signs, nine training ways and “Three Yellow Rivers” policy-making field form the training system of “1493” [5].

3 Measures and their effects of keeping the healthy life of the Yellow River

3.1 The integrated management and dispatching of water resources

The Yellow River is the main water source of northwest and north China, which accounts for 2% of the total rivers’ runoff of the whole nation, shoulders 12% population and water-supplying duty of 15% irrigating area of the whole nation, and shoulders long-distance water transfer to some areas out of the basin. With the rapid development of economic society in the basin and related areas, the supply and demand contradiction of water resources has been increasingly pricking up. From lacking of integrated management of water resources and integrated dispatching of water quantity, water diversion from the Yellow River is in disorder, which results in frequent running dry of the lower Yellow River.

In 1999, the State Council authorized Yellow River Conservancy Commission to carry out the integrated management of water resources and integrated dispatching of water quantity of the Yellow River. Yellow River Conservancy Commission took the following measures:

(1) Administrative measure

A special organization was set up to manage and dispatch water resources of the Yellow River. In the allotting framework of suppliable water quantity sanctified by the State Council in 1987, the corregidor is mainly responsible for control the section discharge and water quantity between provinces and strengthen coordinating management and strict supervision.

(2) Lawful measure

According to “Water Law of the People’s Republic of China”, water quantity dispatching beforehand scheme was made under the emergency of drought, and strictly carried out in the Yellow River in the driest years after warranted by the State Council and ratified by the Ministry of Water Resources.

(3) Technical measure

The collecting, transporting and handling system of hydrological and water quality information of the whole river is constructed. Policy-making of dispatching scheme would be adjusted timely according to the results of beforehand operation and tailing of math stimulating system. Sluices remote control system would operate to control water quantity in emergency, which heightens the science and veracity of water quantity dispatching of the whole river.

(4) Engineering measure

To sufficiently exert the regulating function of the reservoirs to runoff on different reaches on the mainstream, to store water after flood and to supply water in the following spring and according to the water demand of different reaches, the combined dispatching of the reservoirs on the mainstream of the Yellow River is carried out to realize the optimized allocation of water resources.

(5) Economic measure

One measure is to heighten the price of water supply. The second is to push “supply water according to order” in some irrigating areas in lower reaches. The third is to carry out “water right transition” in some irrigating area in upper reaches, that is, under the condition of no total quantity increase, industrial projects offer money to lay bricks or stones for lining the bottom of the water supply ditches in irrigation areas and the water saved from the irrigation areas is sent to industrial projects.

Through the upper mentioned measures, from 1999 to now, the Yellow River realized no running dry for 6 successive years under the condition of running dry for 9 successive years in 1990-1998, although the Yellow River was in successive dry years, inflow was 30% less than the same period of past years (The inflow in Jan. to Jul. of 2003 was 50% less than the same period of past years, which is the smallest since there is measuring records of the Yellow River.) Water resources of the Yellow River played its furthest role in economy, society and ecology.

3.2 Water and sediment regulation

The river course of the lower Yellow River is world-famous “suspended river”. The riverbed is 4-6m higher than the back side at large, the biggest reaches 12m. In 1990s, the successive dry years, long-term small discharge process made the main channel deposited and shrunk more. According to measurement and analysis, deposition in the main channel of lower Yellow River during this period accounted for 90% of all section deposition quantity. Discharge carrying ability of some reaches fell from 6000m3/s in 1980s to 2000m3/s more or less. The serious deposition in the main channel in the lower yellow River is mainly because water and sediment relation in the lower reaches is not harmonious. In order to model harmonious water and sediment relation, Natural water and sediment relation should be regulated with the help of reservoirs on the branches and mainstream.

3.2.1 Water and sediment regulation based on the operation of Xiaolangdi reservoir

Xiaolangdi reservoir is located in the key position of controlling water and sediment that come into the lower reaches. It controls 91% of the runoff and 100% of sediment of the Yellow River. Water and sediment discharge outlets in different elevations of Xiaolangdi reservoir can be combined to control the outflow so that a manual water and sediment relation can be achieved, which is suitable for sediment-transporting feature, and can exert sufficiently the sediment-transporting effect of unit water body under the condition that makes the lower river channel no deposition or scouring.

On July 4 to 15, 2002, Yellow River Conservancy Commission carried out the water and sediment regulation based on the operation of Xiaolangdi reservoir. Average Controlled discharge that comes into the lower channel is 2649m3/s while the average sediment-laden concentration is 13.3kg/m3. It lasted 11 days. The result is that the whole lower channel was scoured, 0.0562 billion ton of sediment was flushed into the sea, scour depth was 0.07-0.26m, discharge carrying capacity increased 90-500 500m3/s[6].

3.2.2 Water and sediment regulation based on the butting of water and sediment process from different sources

The water and sediment regulation mode is based on inflow of high sediment-laden flood above Xiaolangdi reservoir under the condition of inflow of low sediment-laden flood below Xiaolangdi reservoir. A certain flux which lasted a period of time, certain sediment-laden and certain grain grade process is modeled by combining the different water discharge holes of Xiaolangdi reservoir and was loaded on the “clear water” from the branches below Xiaolangdi reservoir and then was made butting well and truly at Huayuankou Station. The harmonious water and sediment relation at Huayuankou Station was formed. The aims of discharging the sediment storage in Xiaolangdi reservoir, making the “clear water” from below Xiaolangdi reservoir loaded with sediment and at the same time, making the lower river channel not deposited are realized.

On September 6 to 18, 2003, Yellow River Conservancy Commission carried out water and sediment regulation based on the butting of different sources of water and sediment processes. Average controlled outflow flux of Xiaolangdi reservoir is 1,690m3/s with average sediment concentration of 40.5kg/m3. At the same time, the average “clear water” flux below Xiaolangdi reservoir was 739m3/s with average sediment concentration of 1.4kg/m3 by operating Luhun reservoir on the Yihe River and Guxian reservoir on the Luohe River below Xiaolangdi reservoir. The upper two water and sediment processes was butted at Huayuankou hydrological station to form an average discharge of 2,394m3/s with average sediment concentration of 31.1kg/m3. The result is that sediment of 0.1,207 billion ton was transported into the Bohai Sea with water of 2.719 billion m3. Sediment of 0.0388 billion t in the main channel of the lower reaches was scoured into the sea. Sediment flushing ratio reached 107% in Xiaolangdi reservoir, namely, the deposition in Xiaolangdi reservoir decreased while the lower river channel was scoured[7].

3.2.3 Water and sediment regulation based on the combined operation of the reservoirs on the mainstream and manually disturbing

This mode is a special design, which is aimed at how to let out the water in reservoirs under the condition of no flood, and reservoirs on mainstream have stored water at the end of last flood and have to let out the stored water to the controlled water level before flood season. That is, manual density current was made in Xiaolangdi reservoir, silting shape at the end of reservoir was adjusted and more sediment in the reservoir was flushed through the combined operation of Wanjiazhai reservoir, Sanmenxia reservoir and Xiaolangdi reservoir on the mainstream; at the same time, manual sediment disturbing in the riverbed of the lower bottle-neck reaches was carried out in which the main channel was deposited most seriously to enlarge the overflowing capacity of the main channel taking advantage of the ample silt carrying capacity.

From June 19 to July 13, 2004, Yellow River Conservancy Commission carried out water and sediment regulation based on the combined operation of reservoirs on the mainstream and manual sediment disturbing. The regulation was carried out in two phases. The first phase was from June 19 to 29. Xiaolangdi reservoir let out clear water according to the standard of the discharge at Huayuankou hydrological station is 2,600m3/s. Manual sediment disturbing was carried out in the lower bottle neck reaches to take advantage of the ample silt carrying capacity of the clear water. The second phase was from July 2 to 13. The man-made flood peak from Sanmenxea reservoir scoured strongly the deposited delta at the end of Xiaolangdi reservoir, which made the sediment out of Sanmenxie reservoir and the fine sediment rushed up from the deposited delta at the end of Xiaolangdi reservoir the sediment source to form a density current moving to the front part of Xiaolangdi reservoir. The density current was discharged out of Xiaolangdi reservoir using the follow-up force of the discharging flow of Wanjiazhai reservoir. This water and sediment regulation adjusted the deposition shape in Xiaolangdi reservoir and scoured the whole lower river channel. The scoured sediment reached 0.0,642 billion ton. The smallest overflowing capacity of the lower main channel heightened from 1,800m3/s before the flood season of 2002 to 3,000m 3/s[8].

The successive three years’ water and sediment regulation during 2002-2004 proved that the deteriorating trend of the lower river course can effectively be kept within limits through molding the harmonious water and sediment relation by water and sediment regulation. With the complement of water resources by water transfer from other rivers, the perfecting of water and sediment regulating and controlling system and constantly adjusting water and sediment relation of the Yellow River, the healthy life of the Yellow River will be restored gradually and would be kept in a virtuous state.



References

Li Guoying, Dialectics of Water Training, China Water Conservancy and Hydropower Publishing House, May, 2001.

Liu Bingyi, etc. The List of “Rivers in Severe Danger” of the United States in 2004, Water News Net, April, 27, 2004.

Huang Shijian, An Introduction to Modern Life Sciences, Higher Education Publishing House, Springer-Verlag, August, 2001.

Chen Minhao, Where to Go, China Forestry Publishing House, November, 2002.

Li Guoying, To Keep the Healthy Life of the Yellow River, Science, N0.3, 2004

Li Guoying, First Water and Sediment Regulation on the Yellow River, Science, No.1, 2003.

Li Guoying, Theory and Practice of Water and Sediment Attempering across Space and Time in the Lower and Middle Yellow River Reaches, Journal of Hydraulic Engineering, No.8, 2004.

Li Guoying, General Design and Implementing Effect of the Third Water and Sediment Regulation Experiment of the Yellow River, China Water Resources, No.22, 2004.


Source: www.yellowriver.gov.cn

离线 紫露草

1楼 发表于2010-11-06 17:31

RE:Keep Healthy Life of Rivers—A Case Study of the Yellow River

了解黄河保护,学习英文!

离线 刘秀

2楼 发表于2010-11-06 18:07
今天我们去调研了一下成都市河流研究会,感触最深的是,河流,很重要,水,很重要,哪儿都不能缺水。。。。

离线 飞天

3楼 发表于2010-11-06 20:11
太难看了

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4楼 发表于2010-11-06 22:40

RE:Keep Healthy Life of Rivers—A Case Study of the Yellow River

不难看啊

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5楼 发表于2010-11-08 11:36

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