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Achieving efficient and coordinated governance of water environment is the key for the country to promote the adjustment of energy structure and achieve the strategic goal of “carbon neutrality”. Based on the theory of collaborative governance, using the questionnaire survey method and the structural equation model, this paper empirically analyzed the collaborative impact mechanism of the behavior of three governance subjects, namely government, enterprise and society, and the trust among governance subjects on the collaborative governance effect and carbon neutralization effect of water environment. It is found that trust among governance subjects, government behavior and enterprise behavior have significant positive impact on the effect of water environment collaborative governance, among which trust among governance subjects has the largest impact; trust among governance subjects, government behavior and social subject behavior have significant positive impact on carbon neutralization effect; synergistic governance effect of water environment plays a part of intermediary role in the relationship between trust between governance subjects, government behavior, and enterprise behavior on carbon neutralization effect. [ABSTRACT FROM AUTHOR]

As the rapid urban development in the Yellow River Basin has brought great pressure to water environment, it is very important to coordinate the relationship between urban development and water quality to ensure the implementation of major national strategy for the Yellow River. In this paper, evaluation index systems were built to calculate the Urban Development Index（UDI） and Water Quality Index（WQI） of 11 cities in the basin from the year 2012 to 2019, and the evolution relationship of coupling coordination between urban development and water quality was demonstrated based on the coupling coordination model. The results show that a) the overall urban development level in the study area is increased year by year and UDI is higher in the “upper and lower reaches” and lower in the “middle reaches”; b) the overall water quality is stable in class Ⅱ and the pollutants are mainly nitrogen and phosphorus nutrients; c) the urban development and water quality are in good coordination. Finally, according to the city characteristics, measures are put forward to enhance the coupling coordination between water quality and urban development, such as strengthening water pollution discharge management and pollution control, driving urban development and environmental governance and protection by scientific and technological innovation. [ABSTRACT FROM AUTHOR]

Weirs are important structures in the management of small and medium rivers. Taking Lingshan River, in Longyou County, as a typical example, based on remote sensing images of 2007,2012,2017 and 2021, combined with field investigations and GIS information extraction, this paper summarized the distribution characteristics of weirs, and quantitatively analyzed the temporal and spatial evolution characteristics of the floodplain landscape pattern index. The changes of the landscape pattern of floodplains pre-and post-construction of weirs and under different distribution methods were discussed. The results show that: a) The distribution of weirs is dynamic and spatially heterogeneous. b) In the past 15 years, the floodplain landscape pattern shows a trend of fragmentation and regularization, but the evolution of floodplain pattern in each river section has significant differences. The degree of fragmentation and edge complexity of the floodplain in the upstream are the most significant. c) A weir has a dramatic effect on the distribution of the floodplain, and the effect of different weir distribution methods on the landscape pattern of the floodplain is highly variable. In general, with the increase of the distribution density of weirs, the fragmentation and morphological changes of the floodplain become more intense. The fundamental reason is that weirs change the hydrodynamic conditions. [ABSTRACT FROM AUTHOR]

In order to realize the goal of regional coordinated development and high-quality development in the Yellow River Basin, based on the core elements of regional coordinated development strategy and new development pattern in the new era, this paper draws on the research method of value chain and combines the input-output data of China’s regions to construct regional coordinated development indicators. The spatial econometric model is used to empirically test the effect of the integrated development level of value chain in different regions on regional coordinated development and its intermediary mechanism. The results show that whether the value chain is embedded forward or backward, it verifies that value chain integration has positive spillover effect on regional coordinated development, and the backward embedding is dominant. The intermediary effect model is used to prove that the deepening of marketization level and the enhancement of the correlation between products are important ways to promote regional coordinated development. The Yellow River Basin can fully enjoy the dividends of regional coordinated development brought by the integration of value chain, but the negative effects of spatial cycle accumulation should be broken. [ABSTRACT FROM AUTHOR]

The biggest contradiction in the Yellow River Basin is the shortage of water resources. Based on agricultural, industrial and ecological water use, this paper identified the current situation of water shortage in the basin. It was predicted that in 2035, the water demand in the Yellow River Basin would reach 54.5 billion m³, while the water shortage would reach 13.6 billion m³, due to the changing situation of water resources in the Yellow River Basin, ecological protection and high-quality development of the Yellow River Basin and other national strategic requirements. Especially, the water shortage in six provinces in the upper and middle regions would reach 10.3 billion m³, accounting for 76% of the total, which made them the most severe regions. The West Route of South-to-North Water Transfer Project can be a fundamental measure to solve these water shortage problems. Those six provinces are the main water-receiving areas and can be supplied with 8 billion m³ of water in the first phase of this project, which can meet the rigid domestic and industrial water demand. [ABSTRACT FROM AUTHOR]

Giving high priority to saving water and spatial equalization should be the principle for the demonstration of water resources engineering. The scientific demonstration of the water transfer scale for the West Route of South-to-North Water Diversion Project should base on the water-saving potential in the Yellow River Basin. Taking the water-receiving areas of the West Route of South-to-North Water Diversion Project as the research areas, this paper analyzed the current situation of water-saving, potential of water-saving and problems in different industries. The results show that the overall water-saving in the Yellow River Basin has reached a relatively high level in China, but its distribution is spatially uneven. The gross and net water-saving potential of the whole Yellow River Basin is about 2.5 billion m³ and 1.9 billion m³ respectively. The gross and net water-saving potential of the water-receiving area in the West Route is about 2.1 billion m³ and 1.6 billion m³ respectively. The water-saving potential in agriculture accounts for more than 80% of the whole Yellow River Basin as well as the water-receiving area in the West Route. The water-saving potential of the Yellow River Basin is far lower than that of the water shortage, and the actual saved water from agriculture is difficult to be transferred to other industries. The shortage of water resources is the essential issue in the Yellow River Basin, it is necessary to construct inter-basin water diversion projects in the future to solve the issue of water shortage. [ABSTRACT FROM AUTHOR]

During long distance water delivery project of pumping station, water hammer protection scheme of conventional pump is usually based on the pumping accident to set up the water hammer protection measures, the influence of buried pipe burst to the transition process of water delivery system is seldom considered. When a point in the downstream pipeline occurs pipe burst, severe water hammer drop can induce secondary or serial pipe burst accident. In this paper, the physical process of buried pipe burst in practical engineering was analyzed and a reasonable mathematical model was established based on the working principle of the overflow stable pressure tower. The pumping accident and the pipe burst accident were considered in the design of water hammer protection scheme and a protection scheme combining the air tank and the air valve after the pump was put forward. Combined with a practical water delivery project, this paper compared the influence of different protection schemes to the protection effect of water hammer in the case of pump stopping and pipe burst. The results show that the conventional water hammer protection scheme can effectively eliminate the harm of pump stopping accident, the combined protection scheme of air tank and air valve can effectively prevent the transmission of the pressure drop wave of the water hammer in the pipe burst accident and avoid the occurrence of the second pipe burst accident. [ABSTRACT FROM AUTHOR]

This paper studied the coordination degree between water environment and social economy in the Yellow River basin from multiple logical and spatial dimensions. Based on the analysis of the interaction between water environment and social economy, the water environment index system of the Yellow River basin was constructed from three logical dimensions of water resources, water pollution and water governance. The coupling coordination model was used to measure the overall coordination degree between water environment and social economy in the Yellow River basin. From the three spatial dimensions of the upper, middle and lower reaches of the Yellow River basin, seven urban agglomerations along the Yellow River and 61 cities, and three logical dimensions of water resources, water pollution and water governance, this paper used Deng’s correlation degree method to measure the correlation level between water environment and social economy and explore its causes. The results show that the overall coordination degree between water environment and social economy in the Yellow River basin is low but increasing. From 2009 to 2018, the correlation degree between the three logical dimensions of water environment and social economy fluctuated between 0.7-0.8 and the spatial differentiation is not obvious. From 2009 to 2018, the correlation degree between water environment and social economy in the middle of the Yellow River basin has been increased, while the correlation degree between water environment and social economy in the upper and lower reaches of the Yellow River basin has been decreased. Taiyuan urban agglomeration shows an increasing trend and Ningxia urban agglomeration along the Yellow River decreases slightly. Among the 61 cities, it needs to focus on the cities of Longnan, Linfen and Baoji that have high correlation between water resources and social economy, the cities of Guyuan, Jincheng and Longnan that have high correlation between water pollution and social economy and the cities of Linfen, Qingyang and Bayannur that have low correlation between water management and social economy. [ABSTRACT FROM AUTHOR]

In order to improve the quality of ecological environment protection, wireless sensor network (WSN) is widely used in the ecol cal environment intelligent monitoring in the Yellow River Basin. The energy consumption and lifespan of sensor nodes are the key iss faced in wireless sensor network routing. In order to reduce the energy consumption of nodes in the routing process and prevent nodes from ing prematurely, the evolutionary algorithm was applied to WSN routing optimization. This paper improved the traditional optimization alg rithm and applied the improved adaptive evolution algorithm to routing optimization, and randomly selected 100-node WSN topology model verify the effectiveness of the algorithm. The results show that compared with the traditional evolutionary algorithm and ant colony algorithm the algorithm in this paper effectively reduces the energy consumption of sensors in the routing optimization of wireless sensor networks, in proves the algorithm convergence speed, prolongs the life of WSN, enhances the connection reliability and realizes real-time monitoring an protection of ecological environment in the Yellow River Basin. [ABSTRACT FROM AUTHOR]

The irrigation area is the key technology for the precision irrigation and charging of the irrigation area. Based on the momentum theorem, this paper designed a new type of device for measuring water flow in open channel. This paper explored the difference of hydraulic properties among different shape flats, and looked for the optimal geometric shape of flat. Using statics analysis on flats in narrow and deep rectangular open channel uniform flow, we found that the relationship between quantity of flume and opening angle of testing flat had a single value corresponding. Combined with experiment outcome in laboratory, for different geometries and shrinkage ratios flats we extrapolated the half theoretical and half empirical formula of flow and range of application. Compared experiment results of designed testing flat, such as, flow range, the measurement error, head loss and flow stability, we concluded that T-shape flat with shrinkage ratio of 0.5 to 0.6 was recom mended. [ABSTRACT FROM AUTHOR]

In order to impound and reinforce warping dams, hascx-l on the fluid solid coupling theory ;md strength reduction method, this paper analyzed the seepage and stability of Hejiazhuang warping dam during its impoundment operation hy using ABAQUS finite clement software, put forward the ideas of seepage prevention and reconstruction such as day inclined wall m1d geomemlmme and calculated and analyzed the stability m1d seepage characteristics of each reconstruction scheme. The results show that : the numerical simulation method used in this paper is foasihle compared with traditional methods ; as a water and soil conservation measure, Hejiazhuang main warping dam did not consider long-term water storage in the original design. If the water storage is normal according to the design standard, its stability docs not meet the requirements, so it needs to he reinforced and reconstructed, and it is difficult to achieve the expected dfcx·t only by using the way of upstream dam slope slowing down ; both the gcomembrane reconstruction scheme and the day inclined wall 1u·onstruction scheme can improve the safety c

The optimization of the industrial layout in the Yellow River Basin is of considerable significance to promote its high-quality development. Based on investigating the basic situation of the industrial layout of the nine provinces (autonomous regions) in the Yellow River Ba sin, this paper depicted the distribution map of key industries in the Yellow River Basin and analyzed the current situation of the industrial layout in the Yellow River Basin and its impact on the Yellow River. This paper also discussed the applicability of three industrial layout models, including the growth pole development, point-axis development and network development under the condition of high quality development in the Yellow River Basin. The industrial layout optimization matching the high-quality development of the upper, middle and lower reaches of the Yellow River was proposed and the expected effect of this optimization's implementation was also studied. The results show that the effective industrial layout models matching high-quality development of the Yellow River Basin are expanding the industrial circle radiation range of existing growth poles and developing new growth poles, strengthening the driving ability to exist industrial axes and developing new shafts, as well as carrying out green and sustainable industrial development. [ABSTRACT FROM AUTHOR]

In the long service of Roller Compacted Concrete Dam (RCCD), deformation is one of the main performance parameters which can directly reflect the working behavior of the dam. In order to effectively monitor the safety of dam operation, it is necessary to determine the monitoring control values for deformation. In order to overcome the limitations which the traditional dam deformation monitoring control values only consider the single point. This paper constructed a deformation field model of RCC dam with multi-measurement point fusion and used Projection Pursuit Analysis (PPA) to determine the weight of each measurement point according to the spatial structure correlation distribution characteristics of RCC dam deformation. On this basis, the POT model was proposed to determine the monitoring control values. The results of engineering application show the feasibility and applicability of the method in this paper. [ABSTRACT FROM AUTHOR]

Wetlands are special ecosystems formed by the interaction between water and land. In order to ensure the rational utilization of wetland water resources and better carry out wetland water ecological environment protection and restoration, water resources management and other work, it is necessary to evaluate the water resources utilization of wetland scientifically. This paper selected the typical wetland in the sedimentladen river wetland, Sanmenxia Reservoir wetland as the study area. Water resources utilization utility was defined as the functional value of wetland ecological services generated by unit water resources. This paper selected 2017 as the base year, combined the calculation of the ecoenvironmental water demand of the wetland and the value of the ecological service function and identified the support of ecological service function of the wetland ecoenvironmental water to the ecological service function. The coupling relationship between various types of wetland ecoenvironmental water damands and ecological service functions and the water resources utilization utility in the Sanmenxia Reservoir wetland was evaluated. The evaluation results show that wetlands have played an important role in landscape protection, water and sediment regulation, water quality purification and ecosystem balance maintenance. Among them, the total ecological water demand in the ecological environment is 0.47 Yuan/ m3 in the Sanmenxia Reservoir wetland. Among them, wetland landscape protection and recreational water demand have the highest utility, which are 19.87 Yuan/ m3 and 6.47 Yuan/ m3 respectively. The water resources utilization utility to maintain the selfpurification ability of water body is the lowest, which is only 0.01 Yuan/ m3. [ABSTRACT FROM AUTHOR]

With the development of internet, new-generation information technology represented by big data, AI and IOT, is accelerating the industrial integration among agriculture, manufacturing and service industries and driving high quality development of China’ s economy. In order to promote the application of new generation information technology in the process of ecological protection and high quality development in the Yellow River basin, this paper analyzed the current situation of natural resources, social and economic development and industrial composition of the Yellow River basin. Then on the basis of discussing the problems faced by ecological protection and high quality development of the basin, this paper put forward the general framework by using new-generation information technology to promote ecological protection and high quality development of the basin, that is to establish the air-space-ground integrated management of ecological environment, improve the comprehensive flood prevention and early warning system, maintain the management and control system of water resources in the Yellow River water supply area, strengthen the optimization and adjustment of industrial structure in the basin and establish a harmonized industrial chain in the basin. On the basis of the framework, it was suggested to establish an air-space-ground integrated big data platform, which could accelerate the ecological restoration along the Yellow River basin and ensure high quality development of the basin. [ABSTRACT FROM AUTHOR]

The Middle Yellow River is an important agricultural and energy production area in China and it also has rich culture. However, the Yellow River flows through the Loess Plateau, where has serious soil erosion and fragile ecology. It poses a serious challenge to the high-quality development of the Middle Yellow River. This paper briefly described the geographical feature, climate environment characteristics, soil and water environment and economic status of the Middle Yellow River. As well as, this paper described the existing problems of the contradiction between water supply and demand, soil erosion, pollution, management mechanism and imperfect public participation. Then, the strategy design was made from six aspects including promoting green development, constructing coordination development, promoting industrial development, strengthening construction and sharing, promoting the Yellow River culture and speeding up the construction of city groups. Finally, a bracing system including strengthening toplevel design, improving water control mechanisms, innovating governance, constructing new development pattern and promoting market-oriented reforms was established for ecological protection and high-quality development in the Middle Yellow River. It was expected that this paper could lay a certain scientific decision-making foundation for ecological protection and high-quality development in the Middle Yellow River. [ABSTRACT FROM AUTHOR]

In order to alleviate the contradiction between supply and demand of water resources and the pressure of water resources, evaluate the present situation of mine water development and utilization, and tap the potential, it is an important work to carry out the utilization of mine water resources. Combing and summarizing the utilization of mine water resources and related concepts and connotations, this paper brought out the related concepts of mine water resources utilization, and pointed out that the available amount of mine water resources was a function of utilization capacity. Mine water resources with corresponding utilization capacity could be divided into two parts. Using the theory of limit analysis, the concept and quantitative relationship of mine water current utilization, theoretical utilization and potential were analyzed. This paper improved and unified the concept system and evaluation method of mine water resources utilization. Taking the Shigetai mining area as an example, the status and utilization potential of mine water resources utilization were evaluated. After calculation, the current situation and theoretical available capacity were 6.02 million m3 -11.59 million m3 and 7.30 million -14.06 million m3 respectively. The current and theoretical utilization potential were 0-1.64 million m3 and 1.32 million m3 -4.10 million m3 respectively. It pointed out the threshold space and excavation direction of the current utilization of mine water resources. [ABSTRACT FROM AUTHOR]

In order to optimize the total water inflow of foundation pit dewatering, obtain the optimal single well water yield and the optimal number of dewatering wells, an optimization model of foundation pit dewatering based on objective function method was established in this paper. Meanwhile, taking the headwork inverted siphon foundation pit dewatering project of Xixiayuan Water Conservancy and Irrigation Area Project in Henan Province as an example, the optimization model of canal foundation pit dewatering in inverted siphon section was established by using the objective function method, and MATLAB optimization toolbox was used to optimize the solution of the canal foundation pit dewatering model of the project example, and GMS numerical simulation software was used to verify and analyze the optimization results. The optimization results show that: under the condition of meeting the construction requirements of the foundation pit and the safety conditions of the surrounding environment, compared with the initial scheme, the total water yield can be reduced by 624 300 m³ and 546 390 m³ respectively according to the pumping and drainage plan by using the Fmincon function and Genetic Algorithm, and the single well pumping capacity and number of wells can also be optimized more reasonably. Therefore, it is feasible to use the objective function method to call the optimization toolbox to optimize the design of foundation pit dewatering and can achieve good optimization effect. [ABSTRACT FROM AUTHOR]

Hekoucun Reservoir is an important part of the flood control engineering system in the lower reaches of the Yellow River. Accurate and quick derivation of the deformation field in the reservoir with high temporal and spatial resolution is of great significance. Synthetic aperture radar interferometry has the advantages of high precision, large range, and spatiotemporal continuity, and proposes a new method for reservoir timing monitoring. This paper selected 24 Sentinel-1A orbit-raising images covering Hekoucun Village Reservoir from January 15, 2020 to December 4, 2020, and combined the particularity and complexity of the reservoir environment to develop time series SBAS-InSAR technology suitable for actual needs. The time series deformation information of the reservoir was obtained and the deformation characteristics of the rear dam area were mainly studied. Through ground GNSS monitoring data and field investigation, it was verified that InSAR technology has high applicability for reservoir monitoring, and can provide data support for the stability evaluation of subsequent reservoirs and the flood control pressure evaluation of the levee in the lower reaches of the Yellow River. [ABSTRACT FROM AUTHOR]

The maximum spiral case pressure of pumped storage power station is related to the strength design of pipelines and the safe and stable operation of unit, and is closely related to the geometric characteristics of diversion system. Based on the rigid water hammer theory, this paper qualitatively analyzed the influence of the length and area of main and branch pipes of the diversion system to the maximum spiral case pressure, and the transition process under the change of the geometric characteristics of the diversion system was numerically simulated and verified. The research result indicates that the maximum spiral case pressure depends on the water inertia in the diversion pipelines. The greater the total water inertia of the main/branch pipe along a pipeline, the greater the maximum spiral case pressure under the load rejection. When the total length of the diversion pipe is constant and the ratio of the main pipe to the branch pipe area is greater than 2, increasing the main pipe length or the pipe area can reduce the total water inertia and improve the spiral case pressure. While the length of diversion branch pipe is constant, the total water inertia can be reduced by reducing the main diversion length or increasing the pipe area, so as to improve the spiral case pressure. [ABSTRACT FROM AUTHOR]

A large number of municipal metro tunnels and water diversion tunnels are constructed by using the shield method, and the ground settlement deformation caused by tunnel construction is the most direct indicator of engineering risk. The Peck formula is the most empirical method widely used in predicting ground surface settlement due to tunnel construction. Based on the measured data of long distance shield tunnel with water-rich sandy stratum, this paper discussed and analyzed the applicability of the theoretical values of the key parameters of the Peck formula, supplemented by model numerical calculations, to obtain the applicability and differences between the actual surface settlement troughs and the theoretical calculated settlement troughs for tunnels with water-rich sandy stratum. The results of the study show that, a) in the case of shield tunnels in deep buried sandy strata with burial depths and excavation ratios H/D＞5 and where geology cannot uncover impermeable layers, the subsidence is generated under undrained conditions and the recommended range of loss rates for the target strata is 0.5% to 1%; b) for the “load-carrying arch”, which is buried at a greater depth and formed within the strata, the vault top is farther away from the vertical distance of the surface settlement, resulting in the measured surface settlement trough width being much smaller than the theoretical calculation of the settlement trough width; c) an improved Lee formula endowed with parameter n is proposed to establish the relationship between the settlement of the tunnel vault and the maximum ground settlement. [ABSTRACT FROM AUTHOR]

The selection of lining structure has always been a focus issue in the design and construction of shield water transmission tunnels. In this paper, the lining structure types used in the existing shield tunnels in China were classified and summarized, and several different lining structures were comprehensively compared from the aspects of engineering safety, construction period and project cost by taking the Chuanqin tunnel in the Xixiayuan Water Transmission and Irrigation project as an example. Through structural selection and force analysis, the superimposed lining structure used by the Chuanqin tunnel in the Xixiayuan Water Transmission and Irrigation project was technically reasonable and feasible, and the structure was safe and reliable. Compared with the previous double-layer lining structure with separate internal and external linings, this lining structure superimposed internal and external linings had the advantages of small construction difficulty, high construction efficiency, easy construction quality assurance, and low project cost, and could be promoted and used for shield water transmission tunnels that beard certain internal water pressure. [ABSTRACT FROM AUTHOR]

In response to the shortage of water resources in China, the state has promoted market-based trading of water rights in order to promote the optimal allocation of water resources. This paper used current policy theory and local reform practice on water rights trading as the object of study, and considered that the water right transaction had three functions of promoting the paid use of water resources, the strictest management of water resources, and protecting private rights. It used the empirical analysis method to identify shortcomings in the logic, compatibility and practicality of these functions, which might lead to the deviation of the correct direction of water right transaction and the public doubt about the illegal and unsafe trading method, the public’s right to know and participation, and the unreasonable trading price. The research thinks that the function of water trading should be repositioned and optimization initiatives pursued. At the macro level, it should be repositioned from the perspectives of maintaining national ownership of natural resources, promote the transformation of government functions and achieve sustainable development. At the micro level, the water rights transaction system should be optimized by promoting the electronic and dynamic registration data of water rights, legalize and rationalize water rights trading rules and expand the participation of the public and the interested party, and scientifically assess trading prices. [ABSTRACT FROM AUTHOR]

As the geological environment of the diversion tunnel is changeable, and shield construction is a complex construction process, the risk probability is high, the risk is difficult to predict, and the economic loss and personal injury caused by the risk are immeasurable. Looking for and analyzing the possible risk sources in shield construction of diversion tunnel is helpful to ensure the safe construction of tunnel engineering. In this paper, for a diversion tunnel, the WBS-RBS method was used to build a risk matrix, identify the risk sources of tunnel shield construction through the study of the matrix, and then determined the weight of each risk factor of the tunnel through the Analytic Hierarchy Process, obtained the impact degree of each risk factor on the progress of tunnel shield construction, and formulated corresponding risk control measures according to the impact degree, so as to provide effective management methods for tunnel shield construction. It made the safety management of tunnel shield construction from post remediation to pre prevention, reduced the probability of risk occurrence, and improved the level of safety management of tunnel shield construction. [ABSTRACT FROM AUTHOR]

Water resources, environment and socio-economic systems interact with each other and evolve cooperatively. Research on the interaction among the three systems is a hot topic at present. In order to explore the coupling and coordination characteristics of water resources-environment-socio-economic system, this paper took Qinghai Province as the research object and constructed a comprehensive evaluation index system. Based on the statistical data of water resources, environment and socio-economic systems in Qinghai Province from 2000 to 2020, it used coupling coordination model and grey correlation model to quantitatively evaluate the coupling and coordination characteristics. The results show that a) during the study period, the evaluation indexes of water resources, environment and socio-economic systems in Qinghai show an upward trend of varying degrees. b) Coupling degree of water resources-environment-socio-economic system is at a high level of integration, and coupling coordination degree is in a transitional stage from intermediate to good coordination. c) Among the three subsystems, the development level of the water resources system has stronger influence to the coupling and coordinated development of Qinghai Province, the environment system is the second one and the socio-economic system has relatively weaker influence. [ABSTRACT FROM AUTHOR]

In order to implement the water resources rigid constraint system and quantify it concretely, based on the in-depth analysis of its conceptual connotation and requirements, following the principles of systematization, difference, operability and measurability, this paper built an indicator system of water resources rigid constraint from four aspects of basic ecological water use, water use control of economic and social development, water use control of different industries and water use efficiency control. It described the uses and determination methods of each index in detail. Finally, the indicator system was applied in the quantitative calculation of rigid constraint index of water resources by water sources and industry in different level years of Gansu Province, and the rigid constraint index system of water resources in 2025 and 2035 in Gansu Province were determined, which was 12.14 billion and 13.22 billion m3 respectively. The result shows that the built indicator system of water-resources rigid constraint has better adaptability and feasibility. [ABSTRACT FROM AUTHOR]

The Middle Route of South-to-North Water Diversion Project (SNWDP) carries out water transfer in the form of open channels, which has the advantages of small investment, low cost and high flow rate, but the open water transfer line also brings the risk of difficult water source protection and easy to cause unexpected water pollution accidents. This paper systematically summarized the research results at home and abroad. Taking SNWDP as the research area and taking the water pollution incident in the Lanhe River control gate-Yinghe River control gate section as an example, it focused on the research of downstream water supply time of the incident section during the accidental water pollution accident, and simulated the downstream water supply time of the accident section using both conventional and optimized water supply methods based on the conventional water supply method of open channel transfer, and proposed an optimized zoning water supply method to extend the downstream water supply time of the accident section. The optimized zoning water supply method was proposed to extend the water supply time downstream of the accident section. The results show that the use of optimal zoning water supply method in the face of large flow diversion downstream of canal/pool can maintain a long period of stable water supply in the downstream canal/pool, effectively extend the water supply time in the downstream of the unfavorable canal/pool and ensure the security of regional water supply. [ABSTRACT FROM AUTHOR]

In the current society, the frequent occurrence of urban floods has attracted wide attention in China. Based on the research literature of urban flood disaster in CNKI Chinese periodical database from 2001 to 2021, this paper used Citespace and SATI3.2 software to analyze the annual publication frequency, journals and institutions, research hotspots, research frontiers and development trends of urban flood disaster related literature. The results show that the urban flood disaster has always maintained a high heat, involving many disciplines and cross phenomenon; the publishing institutions are mainly concentrated in design and planning colleges and universities; sponge city construction, low-impact development and risk assessment are still the main research hotspots. Resilient city, vulnerability and coupling model will be the future research trend. [ABSTRACT FROM AUTHOR]

In order to explore the internal relationship between digital economy and green total factor productivity of manufacturing industry in the Yellow River Basin, this paper empirically analyzes the impact of digital economy on green total factor productivity of manufacturing industry in the Yellow River Basin by using systematic GMM model and panel threshold model based on panel data of 73 prefecture-level cities in the Yellow River Basin from 2011 to 2020. The research shows that digital economy can significantly promote the improvement of green total factor productivity of manufacturing industry in the Yellow River Basin, and this promoting effect is nonlinear with marginal increasing. Further investigation shows that the impact of digital economy on green total factor productivity of manufacturing industry has a single threshold effect based on opening to the outside world and government support. Heterogeneity analysis shows that digital economy has a more significant effect on the improvement of green total factor productivity of manufacturing in the middle and downstream regions. [ABSTRACT FROM AUTHOR]

The middle reaches of the Yellow River is an important national ecological function area and energy base. It is an arduous task to prevent and control soil erosion and protect ecology. In view of the problems of large quantity of soil and water conservation supervision work area, insufficient supervision ability and weak timeliness of traditional supervision way in the Yellow River Basin, this paper puts forward some countermeasures for establishing the pilot demonstration zone of high quality supervision of soil and water conservation in the contiguous area of Shanxi, Shaanxi and Inner Mongolia, and probes into its working mechanism and mode: First, the goal of innovation management is to take the lead in implementing non-violation projects, Second, the goal of innovation cooperation is to jointly build a working system, and build a working mechanism with consistent goals, self-awareness of actions, and coordinated efforts, Third, the endogenous motivation of innovation, taking self-discipline as the core to promote the overall level of credit for soil and water conservation, Fourth, leaders at all levels, construction units, young people and the general public should improve the cognition and ability of ecological civilization in soil and water conservation to achieve the unity of knowledge and practice, Fifth, the connotation of innovation evaluation will be improved to comprehensively enhance the level of scientific and technological support, Sixth, digital empowerment, scientific classified management and innovative smart platform will enable production and construction projects to achieve smart technology guidance, smart tracking, smart early warning. Reset [ABSTRACT FROM AUTHOR]

Under the background of the country’s vigorous development of “double carbon” and the development of clean energy, hydropower projects have been significantly supported and promoted. The investment and construction of hydropower projects are inseparable from accurate value assessment. In order to improve the shortcomings of non-random uncertainty in the traditional investment decision-making method, this paper improved the B-S option pricing model based on the payment dividend and trapezoidal fuzzy number, and combined the free cash flow discount model and the real option model to construct a hydropower station project value evaluation and expansion model. The empirical analysis of small and medium-sized hydropower stations was selected as a case study, and the evaluation results were compared with the evaluation results obtained by the pure application of the net present value method and the real option pricing model to verify the feasibility of the model. The results show that the fuzzy real option method has good applicability for hydropower station projects, the payment of dividends will reduce the option value, and the volatility and option value calculated by the model are more objective and reasonable. [ABSTRACT FROM AUTHOR]

In order to realize the safe operation and long-term service of South-to-North Water Transfer Project (SNWTP), it is significant to avoid adverse effect led by abnormal state of open channel. Considering the fuzziness of evaluation index and one-sidedness of single method, the evaluation index system of open channel was established with objective analysis method. The improved extension-hierarchical analysis model was proposed to determine the subjective weights based on interval quantization in extension theory, then the subjective and objective weights were combined as fusion weight. The advantages of fuzzy comprehensive evaluation method and grey clustering evaluation method were assembled in order to build the grey-fuzzy evaluation method for open channel. Taking the open channel in the Middle Route of SNWTP as an example, the method and model established in this paper were utilized to evaluate its serviceability and the evaluation results prove their validity and feasibility, which can provide a basis for the operation and maintenance of the open channel projects in the Middle Route of SNWTP. [ABSTRACT FROM AUTHOR]

The water body in the Yellow River basin is complex. Rapid and accurate water extraction in the basin is of great significance to the ecological protection and high-quality development of the Yellow River Basin. However, the existing water body indexes can not meet the requirements of removing the inherent mountain shadow of remote sensing images and accurately extracting complex water bodies. Based on Google Earth Engine (GEE) platform and Sentinel-2 remote sensing images, this paper proposed a Yellow River Basin Water Index (YRBWI), and the effect of water extraction results were compared with the Normalized Difference Water Index (NDWI), Modified Normalized Difference Water Index (MNDWI) and Shadow Water Index (SWI). The results show that YRBWI achieves an excellent water extraction effect in the Yellow River Basin, specifically: YRBWI can solve the confusion of mountain shadows and accurately extract water bodies with high sediment content; compared with NDWI, MNDWI, and SWI, YRBWI has the largest OA and Kappa values, indicating that YRBWI has the highest water extraction accuracy; the water body extraction accuracy of YRBWI is insensitive to the change of threshold value and has high robustness. [ABSTRACT FROM AUTHOR]

In order to promote the rational allocation of water resources in Shaanxi Province and the Yellow River Basin and ensure regional water security, based on virtual water theory and inter-regional input-output table of China, this paper calculated the water consumption coefficients of three major industries virtual water volume in Shaanxi Province, and the virtual water trade volume between this province and other provinces in China in 2007, 2010, 2012, 2015 and 2017 with the help of input-output model, and explored the main factors affecting the change of virtual water volume in Shaanxi Province by using gray correlation model. Further, the inter-industry allocation characteristics of virtual water in Shaanxi Province were analyzed and the virtual water trade network between Shaanxi Province and other provinces were established. The results show that a) the coefficient of direct water consumption and complete water consumption coefficient of the primary industry in Shaanxi Province are higher than that of the secondary and tertiary industries, but all show a decreasing trend over this time, indicating that the province’s water use efficiency are constantly improving. b) The primary and secondary industries account for the majority of the virtual water supply in Shaanxi Province, and the level of agricultural technology, population size, urbanization rate, food production, industry and construction development level are the main factors affecting the virtual water supply of the primary and secondary industries in the province. c) More than 70% of the virtual water in Shaanxi Province are consumed by itself and transported to other provinces mainly are Guangdong, Shanghai, Tianjin, Hebei, Shandong, Shanxi, Inner Mongolia and Henan provinces. It mainly exports to the primary industry. More than 90% of the virtual water input derives from the secondary and tertiary industries of Jiangsu, Guangdong, Shanghai, Anhui, Zhejiang and Hunan provinces. d) Shaanxi Province has maintained net input state for a long time in the inter-provincial trade; compared with the actual water resources trade net virtual water trade between Shaanxi Province and Sichuan, Liaoning, Jilin and other provinces is unreasonable. Shaanxi Province should promote the spatial and temporal matching of virtual water and physical water by adjusting the industrial structure and optimizing the inter-provincial trade network, which is of great significance for the rational use of water resources at the Yellow River Basin scale and even at the national scale. [ABSTRACT FROM AUTHOR]

In order to explore the current characteristics of the temporal and spatial changes of water quality in the Taoge Basin, the paper analyzed the future change trend of the water environment in the basin. Taking the main inflow and outflow rivers in the Taoge Basin as the research object, according to the monitoring data of main pollutants of the Taoge Basin from 2020 to 2021 and using the methods such as comprehensive water pollution index and dynamic analysis, it comprehensively evaluated the water quality of the basin. A differential moving average autoregressive model（ARIMA） was selected to perform multi-step forecasting of the main pollution factors of water quality. The results show that the water quality of the Taoge Basin has been generally improved, and the comprehensive pollution index of the Taoge Basin in October 2021 has been decreased by 9.88% compared with that in July 2020. The concentration of total phosphorus, permanganate index and total nitrogen in the water environment of the Taoge River Basin shows a downward trend from 2020 to 2021, with a decrease of 14.57%, 9.36% and 14.78% respectively. But phosphorus is still the main factor restricting the water quality of rivers. The water system is divided based on the connection of rivers and lakes. The comprehensive pollution index of Changdang Lake-Gehu Lake and Beijing-Hangzhou Canal-Xinmeng River water system has been decreased by 7.26% and 9.99% respectively, the comprehensive pollution index of Gehu Lake-West Taihu Lake water system has been increased by13.14%. The ARIMA model can better predict the change trend of river pollutants in a long period of time in the future, which can provide technical support for the water environment management of Taoge River Basin. [ABSTRACT FROM AUTHOR]

In order to improve the effectiveness of interprovincial ecological protection and control in the Yellow River Basin, this paper used evolutionary game model to study the dynamic evolution process of government collaborative management in the upper and lower reaches of the river basin, and analyzed the factors affecting the main body’s strategy selection. The applicability of the model in the Yellow River Basin (Henan-Shandong Section) was evaluated by empirical analysis based on cost-sharing model combined with the “Ecological Compensation Agreement” (hereinafter referred to as “Compensation Agreement”) signed by Henan and Shandong provinces. The results show that a) the stability of the evolutionary game model has nothing to do with the benefits of ecological protection and the ratio of rewards and punishments in the downstream region. The core of upstream and downstream governments’ participation in ecological protection and control lies in whether the maximum reward amount of the government is enough to cover the governance cost. b) When the government’s incentive and constraint amount is more than twice the upstream ecological protection cost, it is more conducive to achieve the overall optimal decision. c) Taking Henan and Shandong provinces as examples, the ecological protection cost and compensation amount of the river basin are calculated. According to the Compensation Agreement, the current compensation amount is relatively small for the importance of the ecological protection of the two provinces and the Yellow River. Based on this, suggestions are put forward to increase the award and punishment, explore diversified compensation methods and promote the sustainable development of ecological compensation. [ABSTRACT FROM AUTHOR]

It is necessary to accurately monitor the scope of land inundated by rainstorm and flood disasters in a short time and evaluate the disaster situation. In this paper, the flood range of “July 20” rainstorm flood disaster in northern Henan was extracted by SAR image. Combined with the land use classification data before flood, the disaster situation of the land inundated by the rainstorm and flood disaster in northern Henan was evaluated by using the system collaborative superposition analysis method. The total area of water body before flood in northern Henan is 9.16 km² and the area of water body after flood is 268.91 km², increasing 259.75 km². Among them, Junxian County, Weihui City and Qixian County are closer to the Taihang Mountains and located at the intersection of Weihe River, Qihe River and Communist Canal. The low-lying area is the main flood detention area. Therefore, the flood inundation range in this area is the largest and the three counties (city) are most seriously affected. The areas inundated by rainstorm and flood are mainly rural areas. The land use types are cultivated land and construction land, accounting for 81.57% and 17.23% of the total affected area respectively. Extracting the flood water body range from SAR image can quickly and effectively monitor the flood inundated area. Combined with land use classification data, it can accurately evaluate the rainstorm and flood disaster, and provide scientific data support and reference for reducing post disaster risk, preventing adverse effects and post disaster reconstruction. [ABSTRACT FROM AUTHOR]

In order to study and discuss the influence of groundwater on each channel section of the Jiaodong Water Diversion Project, this paper used the Analytic Hierarchy Process coupled with Criteria Importance though Intercrieria Correlation (CRITIC) to calculate the weight, based on the variable fuzzy theory, combined with the water quality sampling data and engineering data along the Jiaodong Water Diversion Project, and comprehensively considering the actual conditions, chose the two subsystems of effects of engineering corrosion and effects of engineering form, including seven index values, to construct the impact evaluation system of groundwater on the Jiaodong Water Diversion Project, and analyzed the open and closed channels including nine channel sections. The results show that the average comprehensive score of each channel section is 1.748, in which the comprehensive score of the open canal section is higher (the highest is 2.308 in the section of Pingdu) and the score of culvert section is lower (the lowest is 1.411 in the section of Laishan), indicating that the groundwater has a greater impact on the open channel and a lesser impact on the closed channels. In general, groundwater has weak influence on each channel section of Jiaodong Water Diversion Project. [ABSTRACT FROM AUTHOR]

Planning of guide lines of river regulation is an important evidence for river conservation and regulation as well as water front function maintenance and management. Studying the flood control guide lines of river regulation is of great significance to protect river ecosystem and settle water rights scientifically and rationally. In this paper, thelayout principles of guide lines of river regulation in Qingzhang River were examined and proved. Several guide lines of river regulation width control parameters such as flow per unit width, flow velocity and water level rising value were proposed. Taking the Qingzhang River as an example for further research, the layout principle of the flood control guide lines of river regulation was refined, and the specific control parameters of the flood control guide lines of river regulation were put forward based on the analysis and calculation of the hydrological data of the Qingzhang River, and the application analysis of the results was carried out. The results show that the proposed layout principles and control parameters of flood control guide lines of river regulation are suitable for Qingzhang River, and the flood control guide lines laid out of river regulation in this way are reasonable. [ABSTRACT FROM AUTHOR]

In order to promote low-carbon transition and high-quality development process of agriculture in the Yellow River Basin, this paper used coefficient method to calculate the agricultural carbon effect of nine provinces（regions） in the Yellow River Basin from 2000 to 2020 and analyzed its spatial-temporal evolution law. The fairness and difference of provincial agricultural carbon emissions in the Yellow River Basin were researched from the perspectives of ecological carrying capacity and economic contribution capacity. The results show that the overall agricultural carbon effect of the Yellow River Basin maintains a stable growth trend, with the maximum increase in Inner Mongolia and the minimum increase in Sichuan. The agricultural carbon effect of each province (region) shows the characteristic of net carbon sink. The agricultural carbon effect of the Yellow River Basin shows the unbalanced spatial distribution of “high in the eastern area and low in the western area, high in the upstream and low in the downstream.” Based on the numerical difference of ecological carrying coefficient and economic contribution coefficient in the fairness evaluation model of agricultural carbon emissions, the nine provinces (regions) in the Yellow River Basin are divided into four categories of double-advantage type, ecological dominant type, economic dominant type and double-disadvantage type. Among which, Shandong has always been the double-advantage type; Henan has always been the ecological dominant type; Sichuan and Qinghai have always been the economic dominant type; Inner Mongolia has transformed from the double-advantage type into the ecological dominant type; Shaanxi and Shanxi have changed from the ecological dominant type to the economic dominant type and the double-disadvantage type respectively; Ningxia and Gansu have always been the double-disadvantage type. [ABSTRACT FROM AUTHOR]

Happy River is the new guidance and requirement of river management in the new period of China. In order to provide reference for the measurement and evaluation system of happy river, this paper analyzed the connotation of happy river, summarized the existing methods of river evaluation, and conducted the bibliometric analysis of the research literature. The results show that, the current research in this field is basically based on the concept of river health and human-water harmony. Most of the research is still from the perspective of rivers, and there is a lack of discussion on the mechanism of happiness. The future research direction of happy river evaluation method is put forward: to explore the connotation of happy river and its influencing factors; to study the selection of evaluation index and the construction of evaluation system; and to carry out practical application based on the established evaluation system in the specific watershed, therefore to verify its reliability. [ABSTRACT FROM AUTHOR]

Dredged soil is a kind of material with complex properties and uneven distribution. In order to study the compression characteristics of dredged soil containing organic matter and the corresponding improvement scheme, this paper investigated the engineering indicators of natural dredged soil with 0%-11% organic matter content by experiments. The micro-structure and mineral composition of dredged soil were analyzed by scanning electron microscopy（SEM） and X-ray fluorescence spectroscopy（XRF）. The compression characteristics of improved soil by adding lime, fly ash and volcanic ash were analyzed by one-dimensional consolidation test, and the influence of OMC to the improvement effect was discussed. The study results show that with the increase of OMC, the water content limit of natural dredged soil increases, combined with the density decreasing and the alkalinity decreasing from medium alkalinity to slightly alkalinity. The compression index of natural dredged soil ranges from 0.10 to 0.32. With the increase of organic matter content, the compressibility and expansibility become higher. Both lime and fly ash can effectively improve the anti-compression ability of dredged soil while fly ash has obvious improvement effect on dredged soil with various organic matter contents. When the content of fly ash exceeds 15%, compressibility can be greatly reduced. The volume compression coefficient and compression index increase after the addition of volcanic ash, indicating adverse effects of anti-compression ability. The study can provide reference for the utilization of dredged soil in water transportation projects for building materials. [ABSTRACT FROM AUTHOR]

Border irrigation is the most widely used irrigation method in north China. Optimizing border irrigation technical parameters is an important measure to improve the irrigation and fertilization performance and reduce agricultural non-point source pollution. The multiple technical parameters of border irrigation and the spatial variability of soil infiltration and solute transport parameters make it difficult to study the fertilization performance of border irrigation. This paper collated the commonly used evaluation indexes of irrigation and fertilization performance, summarized the research progress of border irrigation technology factors such as soil texture, fertilization mode, fertilization opportunity and water improvement percentage on the impact of irrigation and fertilization performance, and the appropriate threshold of related parameters, described the application of surface solute transport model suitable for border irrigation and fertilization in different scenes, and summarized the combination of border irrigation technology parameters with high irrigation and fertilization performance. Based on the previous research, the potential research directions in the future were prospected in order to provide valuable reference for further improving crop yield and reducing the impact of fertilizer use on the environment. [ABSTRACT FROM AUTHOR]

Sustainable supplier selection is very important for the sustainable development of water environment treatment PPP project. On the basis of considering the sustainability of suppliers, this paper built a sustainable supplier selection index system from five aspects of financial status, technical strength, management ability, reputation and technical solutions. On this basis, the sustainable supplier decision-making model of water environment treatment PPP project based on probability hesitation fuzzy and Multiplicative and Multi-Objective Ratio Analysisl（MULTIMOORA） method was established. In order to overcome the difference of experts′ cognition, Shapley value method was introduced to modify the index weight determined by AHP. In order to preserve the integrity of decision information to the greatest extent and reduce the complexity of decision model, probability hesitation fuzzy Maclaurin symmetric mean operator（PHFMSM operator） was introduced to integrate decision information. Taking the sustainable supplier selection of a water environment treatment PPP project as an example, the validation of the model showed that it was reasonable to consider the supplier′s own sustainability in the decision-making process, which could improve the reliability of the decision results. [ABSTRACT FROM AUTHOR]

Exploring the beach land function change and its driving factors in the lower reaches of the Yellow River is one of the important ways to promote the optimization and sustainable development of land function in the study area. Based on the land use remote sensing data from 1980 to 2020, this paper analyzed the temporal and spatial variation characteristics of various types of land functional land in the study area, and used geographical detectors to study the influence intensity and interaction mechanism of various factors on the land function change of the river beach and water area in the lower reaches of the Yellow River. The results show that a) the economic and water-sediment functional land covers the largest area and has the widest distribution range. The former is distributed along the river channel, and the area shows a trend of “sharp decrease-slow increase-stable”; the latter is along the river channel. b) Soil type and population spatial distribution are important driving factors affecting land function change in the study area. The spatial-temporal differentiation exhibits two-factor enhancement and nonlinear enhancement. [ABSTRACT FROM AUTHOR]

Urban water demand prediction is an important basis for urban water resources planning, management and decision-making. In order to improve the accuracy of water demand prediction, a nonlinear prediction model based on least squares support vector machine（LSSVM） was proposed. Aiming at the issue that the optimization process of Grey Wolf Optimization Algorithm（GWO） was easy to fall into local optimization, general opposition-based learning and nonlinear control parameters were used to improve the global optimization performance. The improved GWO algorithm was more suitable for the fitting of nonlinear model parameters. Therefore, IGWO was introduced into LSSVM water demand prediction model to fit the super parameters of the model. The model was tested by using the urban water supply data of Shanghai in recent years. The simulation results show that the average relative error of the urban water demand prediction model proposed in this paper is 0.78%, and the maximum relative error is 1.37%. It has good generalization ability and can be used as an effective method of water demand prediction. [ABSTRACT FROM AUTHOR]

In order to comprehensively evaluate the ecological sustainable development capacity of water-energy-food system in the Yellow River Basin, based on the energy theory and method, and combining with the entropy method, this paper built an evaluation index system for the ecological sustainable development capacity of the water-energy-food system in the Yellow River Basin, and comprehensively evaluated the ecological sustainable development capacity of this system from 2008 to 2018. The results show that a) from the overall perspective of the Yellow River Basin, the nexus system belongs to the resource-consuming economic development mode from 2008 to 2018. The rapid economic development has exerted great pressure on the local ecological environment, and the system has been in a state of high environmental load for a long time, resulting in the continuous weakening of the ecological sustainability of the system. b) From the perspective of provinces in the Yellow River Basin, the ecological environment pressure of the lower reaches of the river basin is increasing day by day and the ecological sustainable development capacity is poor. Therefore, the exploitation of renewable resources should be strengthened and the dependence on non-renewable resources should be reduced. The upstream provinces have relatively less environmental pressure and better ecological sustainability. It should strengthen infrastructure construction and promote economic development. c) The overall structural equilibrium of water-energy-food in the Yellow River Basin provinces and regions shows significant variability in time and space, and the ecological sustainability of the system is weakening. [ABSTRACT FROM AUTHOR]

The previous studies on flood evolution in floodplains followed the analysis method of channel flood evolution, which failed to fully reflect the characteristics of floodplain evolution in floodplains. Taking the Changyuan beach in the lower reaches of the Yellow River as an example, this paper proposed a two-line flood evolution diagram of flood flow and direction changing with time in the floodplain. According to the characteristics of flood water volume, the flood evolution characteristics of the floodplain were divided into four types: complete flood discharge, stable flood storage, increasing flood storage, and peak storage and stagnation. According to the flood direction characteristics, the flood evolution characteristics of the floodplain were divided into four types: monostable independent type, single-variable independent type, double-variable independent type, and double-variable cross type. It could more intuitively reflect the distribution characteristics of flood inflow and outflow water volume and direction at different locations in the floodplain. By analyzing the three characteristic values of concentration, consistency and turning angle, the process of flood in the floodplain from dispersion to concentration and then to dispersal under different inundation time and topographical conditions in Changyuan floodplain was analyzed, in order to lay a foundation for the determination of flood inundation information in the floodplain in the future. [ABSTRACT FROM AUTHOR]

Although self-accelerating turbidity current has been demonstrated in theory, it is only occasionally observed at the estuary of some large rivers due to the difficulty in obtaining field currents data. This paper set up a water and sediment density current experimental flume, where the decelerating currents and self-accelerating currents had been achieved under different conditions. Based on this experimental results, adjoined water and sediment characteristics have revealed at current head evolution, thereafter, the experimental results verify the theoretical critical conditions for the occurrence of self-accelerating turbidity current. [ABSTRACT FROM AUTHOR]

Continuous sharp bends exist widely in natural rivers. Studying the law of water and sediment movement has important guiding significance for the regulation and disaster prevention of sharp bends. Based on the movable bed physical model test of unsteady flow bed, this paper discussed the cumulative effect of continuous sharp bends on sediment transport capacity of the lower Yellow River reach. The results show that the continuous sharp bends cause additional energy loss, which leads to the overall deposition of the river channel under specific water and sediment conditions. The sediment transport capacity of the continuous sharp bend sections declines along the river and presents a characteristic of the greater the discharge, the greater the reduction of sediment transport capacity. The horizontal geometric characteristics of sharp bends can be expressed by the product of the ratio of center angle and curvature radius to river width. In the flood stage, the cumulative effect of continuous bends on sediment transport capacity is that the horizontal geometric characteristics of sharp bends are negatively correlated with sediment transport capacity. In the recession stage, when the floodplain discharge is close to the bankfull discharge, the sediment transport capacity slightly recovers in local bends, and after the flow returns to the channel, the horizontal geometric characteristics of the bends and the sediment transport capacity return to a negative correlation again. [ABSTRACT FROM AUTHOR]