Fortune Telling Collection - Free divination - Some information about the Yellow River and the Mother River, I don't want poetry!
Some information about the Yellow River and the Mother River, I don't want poetry!
In the early days of harnessing the Yellow River, there were few basic hydrological stations and basic data, and scientific research on the Yellow River also needed to be carried out extensively and deeply. According to the situation at that time, the guiding principle of "widening the river and strengthening the dike" was determined, which changed the situation of frequent breaches and diversions of the Yellow River and ensured the flood control safety of the Yellow River. Since 1952, the work of harnessing the Yellow River has gradually shifted from the downstream repair and prevention to the permanent cure, and the policy of harnessing the Yellow River has evolved into "eliminating pests and promoting benefits, storing water and retaining sand", mainly adopting soil and water conservation measures for major tributaries and dams, "storing water step by step and retaining mud by step". According to this policy, 1955 compiled the Technical and Economic Report on Comprehensive Utilization Planning of the Yellow River. During this period, the scientific research on harnessing the Yellow River developed rapidly, and many valuable scientific research results were obtained. ?
In the early 1950s, more than 500 scientific and technical personnel visited the Loess Plateau for more than ten months, and got a comprehensive and systematic understanding of the natural conditions and socio-economic conditions of the Loess Plateau. The division of different types of loess plateau provides a scientific basis for determining the direction and measures of governance according to local conditions. From the early 1960s, through the analysis of the particle size of sediment in the lower reaches of the Yellow River, it was recognized that 80% of the surface sediment in the main channel was coarse sediment with a particle size greater than 0.05 mm. Further detailed investigation and analysis were made on the coarse sediment, and it was found that the main source area of coarse sediment in the Yellow River was distributed in the loess hilly and gully region at the junction of Shanxi, Shaanxi and Mongolia, which was about 65.438+1100 million km2. On this basis, the key areas for harnessing the Loess Plateau are determined, and the suggestion that the source area of coarse sediment in the middle reaches is concentrated as the harnessing strategy of the Yellow River is put forward. It is pointed out that the source area of coarse sediment should be treated first to control the downstream siltation deterioration. This is a major breakthrough in understanding the sediment law of the Yellow River and plays an important guiding role in soil erosion control in the Loess Plateau. ?
Based on the study of the problem of coarse sand in the Yellow River basin and the characteristics of soil erosion in the Loess Plateau, a series of major macro-strategic issues such as prevention and control methods, engineering layout and engineering focus of soil and water conservation in the Loess Plateau are solved theoretically. In the study of the law of soil erosion and the benefit of water and sediment reduction by soil and water conservation measures, the factors of soil erosion such as topography, rainfall, soil and vegetation in different erosion rainfall areas were observed by combining large watershed, small watershed and single measure, and the soil erosion equations suitable for different situations were put forward, and the sources and quantities of runoff and sediment produced by different landforms and erosion types were preliminarily analyzed. Through plot experiment and artificial rainfall experiment, the quantitative relationship and sediment yield model of different land types, slopes, slope lengths and soil and water conservation measures on soil erosion are obtained, and the sources of runoff and sediment of different erosion types and the effects of various soil and water conservation measures on soil conservation are basically found out. These research results provide scientific basis for the planning, design and benefit analysis of soil and water conservation, and also provide basic data and theoretical basis for the evolution of the Yellow River regulation strategy. ?
After the application of "water storage and sediment retention" in Sanmenxia Reservoir, the reservoir area quickly silted up, and the study on the characteristics of reservoir siltation made people realize the complexity and limitations of sediment retention. Based on the operation and reconstruction of Sanmenxia hub, this paper studies the siltation of Sanmenxia reservoir and the evolution law of downstream river course, and puts forward the evolution trend of downstream river bed after flood detention and sediment discharge in Sanmenxia reservoir and some suggestions for recent regulation. Through the practice of controlling and dispatching Sanmenxia Reservoir, the understanding of how to maintain the effective storage capacity, the siltation law of the reservoir, the choice of discharge scale and the operation mode of the reservoir in the sediment-laden river is innovative in theory, enriching and developing the sediment science and the theory of water and sediment regulation in the sediment-laden river reservoir, and providing valuable experience for the future reservoir construction. ?
The experience and lessons of Sanmenxia project practice have improved people's understanding of the role of dam repair and sand retention in sandy rivers. The study on the law of soil erosion and the benefits of water and sediment reduction by soil and water conservation measures shows that the work of soil and water conservation is arduous and long-term. The study on the evolution law of erosion and deposition in the lower Yellow River shows that the lower Yellow River has the law of "more sediment and more discharge", which promotes the transformation of the general plan of harnessing the Yellow River from "storing water and blocking sand" to "blocking the upper part and discharging the lower part". ?
Since the Eighth Five-Year Plan, the calculation method of rainfall runoff and sediment has been further improved, the changes of water and sediment since the 1970s and their causes have been analyzed, and the changing trend has been predicted. Based on years of systematic research on the application of dam system in Liudao small watershed in loess hilly and gully region, the conditions, standards and quantitative methods of relatively stable dam system in gully are clearly put forward, the evaluation index system of economic, social and ecological benefits of small watershed is preliminarily studied and formulated, and the influence of coarse sediment interception on the change of scour and siltation in the Yellow River channel is put forward. On the basis of in-depth study on the regional definition and the law of sediment yield and transport in the middle reaches of the Yellow River, the range of coarse sediment in the Yellow River is further defined and the coarse sediment areas are divided. These results provide a scientific basis for determining the control model and making the ecological environment construction plan in the sandy and coarse areas of the Loess Plateau. ?
Through further study on the characteristics of hyperconcentrated water flow, flood evolution, sediment transport and river bed evolution, the long-distance transport of hyperconcentrated water flow is discussed, and it is found that narrow and deep rivers have strong sediment transport capacity, and the idea of transporting hyperconcentrated water into the sea by using downstream rivers is put forward. In the study of the basic theory of sediment movement, the formulas of sediment carrying capacity, movable bed resistance, velocity distribution and suspended sediment concentration distribution of rivers and the comprehensive stability index of rivers are put forward. By studying the change process of vertical and horizontal sections of the lower Yellow River under different water and sediment conditions, the change law of vertical and horizontal sections of the lower Yellow River caused by the decrease of water and sediment is expounded, which has guiding significance for the management of the lower Yellow River. These achievements provide a theoretical basis for the formation and development of the "discharge" strategy. ?
Based on the study of water and sediment regulation in Xiaolangdi Reservoir and measures to slow down sedimentation in the lower reaches of the Yellow River, a new idea of sediment treatment combining "regulation" and "discharge" is opened up, and the effect of "discharge" on sedimentation reduction in the lower reaches of Ai Shan is analyzed. For the study of downstream sediment treatment and utilization, "river digging" is put forward as a new way to slow down the siltation of the river below Ai Shan; A set of sediment treatment measures from the head of the canal to the field are put forward. On the premise of not disturbing the existing layout of the irrigation area of Yellow River Diversion, and making full use of the water diversion and sediment diversion capacity of the existing sluice, this paper puts forward the idea and overall layout of building an underground river by using sediment from Yellow River Diversion, preliminarily analyzes and studies the impact of sediment deposition on the environment and its prevention measures, and puts forward a new idea of "releasing" in combination with the construction of an underground river project by sediment deposition from Yellow River Diversion. ?
By studying the development and evolution law of the estuary channel, the movement direction of sediment in the estuary, the conditions of extension and erosion of the estuary and the evolution mechanism of the bar sand in the Yellow River estuary, the position, formation process, evolution characteristics and its influence on the evolution of the estuary reach are expounded, which provides a scientific basis for the regulation of the Yellow River estuary. ?
According to the analysis and research on the characteristics of rainstorm in the Yellow River basin, the main source area of flood in the lower reaches of the Yellow River is determined. Through the analysis of the flood characteristics of the Yellow River, it lays a foundation for the determination of flood control standards and flood control dispatching in the lower reaches. According to the measured flood and historical flood, through the comprehensive research and calculation of rainstorm displacement possibility analysis and historical flood process analysis, the standard and possibility of catastrophic flood in the downstream are determined, which promotes the formation of "detention" strategy. Among them, the research results of the calculation principle and method of the possible maximum rainstorm flood were recommended by the Hydrological Committee of the United Nations World Hydrometeorological Organization (WMO) as "Revision and Update of the PMP/PMF Best Practice Manual" and included in the Flood Control Standard of China. ?
In the study of wandering river regulation in the lower reaches of the Yellow River, a large number of aerial photos, satellite photos and the data of mainstream routes are systematically sorted out and analyzed, and the riverbed model test is carried out. This paper studies the stability index of river pattern, river pattern transformation and the mechanism of "cross river" and "oblique river", systematically summarizes the experience of river regulation in the lower reaches of the Yellow River, puts forward the principles of river regulation, demonstrates the rationality and feasibility of the regulation scheme of slightly curved river, and deeply studies the influence of river regulation in the lower reaches of wandering river on this reach. These research results have been applied to guide the regulation of the lower reaches of the Yellow River and achieved good results. ?
The Yellow River is the largest water source in northwest and north China, and the rational allocation of water resources of the Yellow River is an important strategic task related to the social and economic development of this region and even the whole country. In the past 50 years, through the research on the utilization of water resources in the Yellow River, some important laws have been preliminarily grasped, such as less water and more sediment, different sources of water and sediment, uneven distribution of water resources in time and space, concentrated distribution in the year, great interannual changes, long continuous dry season in the basin and so on. It is pointed out that the average natural runoff of the Yellow River basin for many years is 58 billion m3, which solves a large number of key technical problems in the utilization of water resources and provides scientific basis for the scientific management, dispatching and distribution of water resources in the Yellow River. Among them, the prediction scheme of water resources utilization of the Yellow River in 2000 was approved by the State Council as "the allocation scheme of available water supply of the Yellow River before the implementation of the South-to-North Water Transfer Project", which is being implemented by relevant provinces, autonomous regions and departments as the basic basis for unified water regulation of the Yellow River.
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