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Due to overload, large flow and high water level operation, the cascade pumping station system has such accidents as canal col- lapse and tripping and stopping, and the water delivery system has entered the hydraulic transition state from the constant flow state, and the hydraulic transition process will cause the problems such as the draining or overtopping of the water inlet basin, which seriously threatens the safety of the plant and equipment of the pumping station. Based on Realizable k-e model and VOF model, this paper took the long-distance open channel of Jingtaichuan Electric Power Irrigation Phase II Project in Gansu Province as the research object. Under the working condition of overflow caused by the accident shutdown of multi-step pumping station, numerical simulation was carried out to analyze the different channel lengths, the water surface line of the slope and the distribution rules of hydraulic oscillation under the action of regulation and storage system of the No.1 to No.7 main channels of Jingtaichuan Electric Power Phase II Project. The results show that the hydraulic oscillation of the water level after the pump station is shut down occurs alternately, and the main reason for the inconsistency of the peak water level is the slope of the channel. The backtracking distance of obstructing waves in different channels is different, and the overflow time on the overflow weir is mainly during the first oscillation of water level. [ABSTRACT FROM AUTHOR]

In order to fully explore and realize the value of soil and water conservation carbon sink in the Yellow River Basin, and effectively promote its development and market trading, on the basis of clarifying the connotation and characteristics of soil and water conservation car- bon sink in the Yellow River Basin, its quality was evaluated from three dimensions; the contribution quality of new carbon storage, the contribution quality of sustainable development, and the quality of carbon sink production process. This paper built an evaluation index system composed of 3 first-level indicators, 14 second-level indicators and 47 third-level indicators, and pointed out the appropriate methods for determining the weights of indicators at all levels and the methods for calculating the carbon sink quality index of soil and water conservation. It suggests that: firstly, we should carry out a whole process pilot project in the Yellow River Basin including high-quality soil and water conservation carbon sink development, monitoring and accounting, carbon sink project rating, information disclosure, and market trading; secondly, we should strengthen international cooperation and exchanges, learn from the differentiated pricing mechanism of the international voluntary emission reduction market, and build a carbon sink pricing system for soil and water conservation in the Yellow River Basin. [ABSTRACT FROM AUTHOR]

The security of agricultural water resources is crucial for food security, ecological environment and the economic development of rural areas. In order to promote efficient utilization and sustainable development of regional agricultural water resources, taking into account the impact of uncertainties and complexities, this paper adopted methods such as ordinal relation analysis, entropy weight method, and TOP- SIS (Technique for Order Preference by Similarity to Ideal Solution) to select 11 typical indicators across three subsystems of water resources, ecology and agricultural water use to build an evaluation index system. This system was used to assess the agricultural water resources security status in 14 prefecture-level cities within the Yellow River water diversion area of Henan Province in 2022. The results show that among the 14 prefecture-level cities, except Kaifeng is the "unsafe" level and Xinxiang, Hebi, and Puyang are the "generally safe" level, the other 10 cities are the "relatively safe" level, which still has some distance away from the "safe" level. It recommends to implement measures such as improving water quality, increasing available water resources, adjusting crop planting structures, enhancing water resources utilization efficiency, and enforcing the strictest water resources management system to ensure the agricultural water resources security in the Yellow River water diversion area of Henan Province. [ABSTRACT FROM AUTHOR]

In order to solve the issue of water scarcity in coal mining areas, this paper collected hydro-geological data from 18 typical coal mines from six major coal mining areas of Hebi, Jiaozuo, Yongcheng, Pingdingshan, Yima and Zhengzhou in Henan Province and evaluated the utilization of groundwater resources in coal mine goaf areas, by using the AHP-set pair analysis to construct an evaluation index system. with utilization of groundwater resources in typical coal mine goafs in Henan Province as the target layer; water quantity, water quality and current status of water resources utilization in mining areas were taken as the criterion layer; twelve evaluation indicators, including mine water inflow, average coal thickness, goaf area, maximum mining depth, roof lithology, complexity of geological structure, total hardness, total dissolved solids content, pH value, chloride ion content, mine water utilization rate and incentive policies were taken as the index layer. At the same time, it also evaluated the utilization of groundwater resources in coal goafs in Henan Province and compared the results with those obtained from analytic hierarchy process. The results show that the evaluation results of the two methods are basically consistent. The utilization feasibility of groundwater resources in typical goaf of six coal mining areas in Henan Province is the best in Jiaozuo mining area, the worst in Yongcheng mining area, and the other four mining areas are in the middle and the evaluation results are similar, indicating that the evaluation index system and evaluation results of typical goaf groundwater resources in Henan Province built by AHP-set analysis method are relatively reliable. [ABSTRACT FROM AUTHOR]

This paper systematically reviewed the inflow and outflow water and sediment, flushing and deposition rule, changes of flood regulation storage capacity and restoration measures of Wanjiazhai Reservoir. The results can provide scientific and technological support for the scientific reduction of sedimentation in the flood control capacity of Wanjiazhai Reservoir. The results show that a) the operating water level of Wanjiazhai Reservoir in non-flood season from 1999 to 2023 ranges from 952 m to 980 m. The operating water level ranges from 950.9 m to 967.2 m in the flood season from 1999 to 2010, and the lowest water level is 921.6 m after the operation of the reduced water level in the flood season from 2011 to 2023 (except 2016). b) From 1999 to 2023, the average annual inflow of Wanjiazhai Reservoir is about 18.519 billion m³ and the average annual sediment volume is about 50.1 million tons, and the average annual discharge is about 18.070 billion m³ and the average annual sediment volume is about 36.3 million tons. c) The longitudinal profile of Wanjiazhai Reservoir after the 2010 flood basically reaches the designed equilibrium state of sedimentation. Since 2011, the reservoir has been used for sediment discharge. As of October 2023, the total storage capacity has lost 285.9 million m³ due to sedimentation, and the siltation loss of the flood regulation storage capacity has reached 19.1 million m³. d) The long duration and high flow process of the Wanjiazhai Reservoir is beneficial for reducing water level and using open discharge for sediment discharge. When the water level in front of the dam is below 952.00 m, the sediment content in the sediment discharge increases rapidly, and when it drops below the sedimentation surface or when the discharge is open, the upstream erosion generated is beneficial for improving the sediment transport efficiency. It is advisable to implement open discharge and sand discharge during the flood season in normal and dry years, and to maintain it for 5 to 15 days as much as possible. e) Relying solely on hydraulic dredging is no longer effective in restoring the flood regulation storage capacity of Wanjiazhai Reservoir. A combination of hydraulic dredging and mechanical dredging can be used to reduce sedimentation. The dredged sediment can be transported to the main river channel for dynamic discharge or to the shore for comprehensive utilization of sediment. [ABSTRACT FROM AUTHOR]

Xixiayuan Reservoir, as a counter-regulating reservoir of Xiaolangdi Reservoir, plays an important role in regulating the unsteady flow of Xiaolangdi Reservoir. Since the operation of Xixiayuan Reservoir, the reservoir has shown a continuous trend of siltation. It is of great significance to study the siltation removal capacity of Xixiayuan Reservoir. Based on the measured water and sediment data of Xixianyuan Reservoir from 2011 to 2022, this paper made an in-depth analysis of the sediment discharge process and influencing factors of Xixianyuan Reservoir over the years. The research results show that the sediment discharge of Xixianyuan Reservoir is affected by multiple factors such as the reservoir operation mode and the conditions of incoming water and sediment. The sediment delivery ratio of the reservoir is significantly affected by the variation coefficient of discharge along the flow and the sediment discharge in the reservoir, and the sediment discharge ratio is significantly positively correlated with the variation coefficient of discharge along the flow and negatively correlated with the sediment discharge in the reservoir. The empirical formula of sediment discharge is established by regression analysis, with the coefficient of determination of 0.79, and the fitting effect is good. [ABSTRACT FROM AUTHOR]

In order to provide scientific support for innovation-driven green development in the Yellow River Basin, this paper studied the coupling and coordination relationship between scientific and technological innovation and green development in eight cities in Henan section of the Yellow River Basin. Based on the panel data of eight cities from 2012 to 2021, the subjective and objective weighting method and the coordinated development degree model were used to explore the temporal and spatial coupling characteristics of scientific and technological innovation and green development system in Henan section of the Yellow River Basin. The results show that: The scientific and technological innovation and green development indexes of the eight cities all increased significantly, but due to the low starting point of scientific and technological innovation, most of the cities still showed lagging development of scientific and technological innovation. The coupling degree of scientific and technological innovation and green development in cities continued to improve, and there was an obvious positive correlation between the two systems. The coordinated development degree of scientific and technological innovation and green development in the basin presents has been improved to varying degrees, and there was spatial heterogeneity. Zhengzhou and Luoyang were the coordination areas of green innovation, Xinxiang, Jiyuan, Sanmenxia, Jiaozuo and Kaifeng were the run-in areas of green innovation, and Puyang was the antagonistic area of green innovation. Based on the research conclusions, suggestions were put forward to improve the coupling level of scientific and technological innovation and green development, such as strengthening the effectiveness of innovation achievements supply in the green innovation coordination area, improving the scientific and technological innovation level in the green innovation running in the area, and making up the shortcomings of scientific and technological innovation in the green innovation antagonism area. [ABSTRACT FROM AUTHOR]

Since this century, due to the dual influence of climate change and strong human activities, the water and sediment conditions en- tering the Lower Yellow River (LYR) have changed significantly. Consequently, the cross-sectional geometry of the LYR channel has been adjusted drastically under the long-term non-equilibrium sediment transport state, which affects river regime stability directly and threatens the flood control safety on both sides of the river seriously. In this paper, based on the measured cross-sectional data of Baihezhen-Gaocun reach of the LYR from 2001 to 2021, the evolution characteristics of the morphological parameters of cross-section were analyzed. On this basis, Heigangkou-Liuyuankou reach was selected as the proto type and a physical model experiment was conducted, to quantitatively reveal the adjustment of cross-sectional morphology under non-equilibrium sediment transport conditions. The analysis of the prototype measurement data found that cross-sectional morphology of the Huayuankou-Jiahetan reach was more variable compared with other sections of the LYR. A typical river section in the Huayuankou-Jiahetan reach was selected as the prototype, and a physical model was constructed using a horizontal scale of 600 and a vertical scale of 60. Keeping the same initial river boundary conditions, channel morphology adjustment experiments with four types discharges of 2 000 m³/s, 3000 m³/s, 4000 m³/s and 5 000 m³/s and different inlet sediment concentration were carried out. The experiment results show that when the inlet sediment concentration is small, the main channel erosion, the area increases and the river phase coefficient decreases. When the inlet sediment concentration is large, the main channel sedimentation, the area decreases and the river phase coefficient increases. Comparing the experimental data with the prototype data, the analysis reveals that the morphological parameters at river reach scale are well correlated with the incoming sediment coefficient under non-equilibrium sediment transport conditions, among which the main channel area is exponentially negatively correlated with the incoming sand coefficient, and the river phase coefficient is qua- dratically correlated with the incoming sediment coefficient. [ABSTRACT FROM AUTHOR]

In order to promote the green, low-carbon and high-quality development of agriculture, this paper adopted the super-efficiency SBM model and the entropy method to measure the agricultural carbon emission efficiency and the high-quality development level of agriculture in the Yellow River Basin, and discussed the interaction between the two by using VAR model. The results show that a) the agricultural carbon emission efficiency in the Yellow River Basin is on the rise as a whole. The agricultural carbon emission efficiency of Gansu and Shanxi, Sichuan, Shandong, Henan, Shaanxi and Qinghai, Ningxia and Inner Mongolia is at a lower, medium and higher level respectively. b) The overall level of high-quality agricultural development shows a fluctuating upward trend. Shaanxi, Shanxi, Ningxia and Inner Mongolia, Qinghai and Gansu, Henan, Sichuan and Shandong are at a lower, medium and higher level respectively. c) The improvement of agricultural carbon emission efficiency has a significant effect on the promotion of high-quality agricultural development, while the improvement of high-quality agricultural development has no significant effect on agricultural carbon emission efficiency. Based on the research results, some suggestions were put forward to improve the efficiency of agricultural carbon emissions and promote the high-quality development of agriculture in the Yellow River Basin from the aspects of green and sustainable development. [ABSTRACT FROM AUTHOR]

Clarifying the relationship between hydrological connectivity and flood probability is an important basis for scientific development of flood management measures. In this paper, the hydrologic connectivity index (RIC) of the Kuye River (KYH) catchment was measured by using a modified hydrologic connectivity model based on hydrologic observations and remote sensing data. Advanced spatial analysis tools and statistical tests, including the Theil-Sen Median and Mann-Kendall methods, were employed to analyze the spatial-temporal evolution patterns of RIC. An ordered logistic regression model was then used to examine the influence of RIC on flood probability. The results indicate a significant decline in the yearly average RIC value. Significant reductions in RIC are primarily observed in specific regions. Spatially, RIC concentrations with high-high agglomeration are in the downstream rock mountainous areas of KYH. Notably, low-low aggregation is found in the Ulan Mulun River catchment, particularly in the Kangbashi and Yijinhuoluo. The trend of long-term significance change is dominated by highly significant decrease and significant decrease. Floods in KYH are mainly concentrated in the summer, with their frequency and annual maximum instantaneous streamflow (AMS) showing a significant downward trend. The mutation point of AMS is found to be in 1998 by the Mann-Kendall test in KYH. The RIC significantly contributes to the probability of flood occurrence. Specifically, when all other variables are fixed and unchanged, for each unit increase in the RIC, the probability of a flood becoming a larger magnitude increases by 5.999 times. [ABSTRACT FROM AUTHOR]

This paper aimed to address the challenges of climate change and water scarcity in the sustainable development of agriculture in the Yellow River Basin by promoting the cultivation of drought-tolerant crops, thereby alleviating regional agricultural water pressure and analyzing their water-saving and carbon-reducing synergistic effects. The study has designed different development scenarios including trend as usual, slow growth, technology-driven and policy-supported scenarios, formulating the analysis schemes for the water-saving and carbon-reducing synergistic effects of expanding the cultivation of four drought-tolerant crops of wheat, maize, sorghum and potato. The agricultural water-saving potential correction model and the agricultural carbon reduction potential model were utilized to quantitatively evaluate the water- saving effects and carbon-reduction potential of expanding drought-resistant crops under different scenarios. The results show that wheat and maize have the largest planting areas, while sorghum and potato have relatively smaller areas. Under the policy-supported scenario, the expansion scale of these crops will reach to 231.2 thousand hectares (wheat), 173.4 thousand hectares (maize), 346.8 thousand hectares (sorghum) and 404.5 thousand hectares (potato) by 2060. In the technology-driven and policy-supported scenarios, the water-saving and carbon reduction effects of crops in the middle and lower reaches of the Yellow River will be significantly increased, the total water saving in the study area will reach to 15.35 billion cubic meters, and the average carbon reduction potential will reach to 65.93 t/km² by 2060. There- fore, promoting drought-tolerant crops in the middle and lower reaches of the Yellow River can help alleviate water scarcity, ensure regional food security, and achieve multiple goals of water-saving, carbon-reduction and income-increasing. [ABSTRACT FROM AUTHOR]

Accurately predicting the flood peak discharge increase phenomenon in the Yellow River during the period of water and sediment regulation is not only an urgent need for reservoir dispatch and flood control, but also a new topic for hydraulics and river dynamics research. This paper took the value-added ratio as the dependent variable, the sediment concentration peak, the average rate of increase during the peak period of the sediment concentration, the base flow before the sediment concentration rises, the particle size of suspended sediment at Xiaolangdi Station as the independent variables and the correlation analysis was conducted. As a result, the sediment concentration peak at Xiaolangdi Station and the average rate of increase during the peak period of the sediment concentration are filtered out, as the prediction parameters for the flood peak discharge increase. The study proposes that the flood peak discharge increase phenomenon may occur in the Lower Yellow River when the average increase rate during the peak period of the sediment concentration at Xiaolangdi Station exceeds 22.9 kg/m³h, and the value-added interval can be predicted on the basis of the correlation between the peak sediment concentration and the value-added ratio of flood peak discharge. By tracking the real-time water and sediment conditions at Xiaolangdi Station during the water and sediment regulation in 2023, prediction and forecasting of the flood peak discharge increase phenomenon was carried out, the prediction results are basically consistent with the measured results. [ABSTRACT FROM AUTHOR]

The major national strategy of ecological protection and high-quality development in the Yellow River Basin has been proposed for nearly five years. During this period, the levels of ecological protection, governance, and development in the Yellow River Basin have been rapidly improved. However, the issues of the Yellow River are longstanding and highly complex, far from being resolved overnight. Given the current situation and unresolved challenges in the Yellow River Basin, there is an urgent need to systematically summarize the research and achievements of the past five years, and to provide prospects for future development. This article systematically summarized the research and contributions made by various sectors of society to the Yellow River since the proposal of the major national strategic plan, focusing on scientific research projects, academic papers, academic monographs, and research platforms. Based on in-depth study of the major national strategic ideology and theories such as systems theory, dialectical materialism, and the theory of harmony, and combined with the current situation of the Yellow River Basin and the urgent major issues that need to be addressed, the article presented five prospects for the future development of the Yellow River Basin; multi-disciplinary integration, multi-department collaborative governance, multi-level joint research, multi- platform talent training, multi-approach protection and governance. [ABSTRACT FROM AUTHOR]

As the mother river of China, the Yellow River Basin serves as a crucial ecological domain and economic zone, as well as a vital source of food and energy. It plays an indispensable role in the political, economic, and cultural development of the nation. The ecological protection and high-quality development of the Yellow River Basin have become a major national strategy in China. Yet, the Yellow River is among the most complex and challenging rivers in the world. Throughout China's long history, especially since efforts began to regulate the river, significant achievements have been made in its management and ecological protection. However, many critical issues still need to be addressed. This paper explored the rich history of the Yellow River Basin management and successes, examined the current situation and challenges, and provided recommendations and strategies for achieving long-term stability, sustainability, and high-quality development in the Yellow River Basin, such as constructing the water resources security system of the basin, realizing the restoration and protection of the ecological environment in the key areas in the basin, and improving the engineering system of flood control, ice-flood prevention and water-sediment regulation in the basin, etc. [ABSTRACT FROM AUTHOR]

In order to explore the effects of soil, fertilizer and water factors on agricultural output in Xinjiang arid and purely irrigated agricultural irrigation area, this paper, from the new perspective of grain storage in the ground, applied stepwise regression statistical test method to screen and analyze multi-dimensional input factors and output indicators, and formed the relationship between the proportion of soil texture loam area, pure fertilizer application amount, irrigation water consumption and main crop yield in the irrigation area. Cobb-Douglas model was used to analyze the correlation effect of soil, fertilizer and water in irrigation area. The results indicate that a) the quality of cultivated land (based on the proportion of loam area), fertilization level and irrigation water consumption (i.e. soil, fertilizer and water) are the basic elements of the input-output system in irrigation areas. b) The order of marginal effects of cultivated land quality, fertilization level and irrigation water usage on crop output in irrigation areas is: pure fertilizer application rate Δf＞ irrigation water usage Δs＞ proportion of soil texture and loam area Δt. c) The order of the proportion coefficient of the impact of soil, fertilizer and water on crop output is Kirrigation water＞Kfertilization＞Kcultivated, reflecting the primary and secondary relationship between irrigation, fertilizer and soil texture conditions, indicating that soil, fertilizer and water are the core contents of high standard agricultural water conservancy. d) The optimization analysis of irrigation areas shows that the irrigation water consumption of 8 203 m³/hm² is similar to the current situation, slightly higher than that the 5.98% of Xinjiang’s landmark irrigation water quota. The optimized fertilizer application rate of 260 kg/hm²can save 15% compared to the current situation. [ABSTRACT FROM AUTHOR]

In order to analyze the ecological management effect and future vegetation restoration potential of Ejina Oasis at the tail of the Heihe River, Normalized Difference Vegetation Index (NDVI) was extracted based on the MOD13Q1 data set from 2000 to 2020. This paper used Sen trend and M-K test to analyze the spatiotemporal variation characteristics of vegetation in the Ejina Oasis. Considering the factors of topography, geomorphology, hydrology, soil and vegetation type, the similar habitat method was used to explore the potential and spatial pat- tern of oasis vegetation restoration. The results show that NDVI shows an increasing trend from 2000 to 2020, and the annual growth rate is 0.001 3/a. The proportion of areas with a significant increase in NDVI in spring on a seasonal scale is the highest. The vegetation coverage near the Ejina Banner government is relatively high and the vegetation coverage in the middle reaches of Xihe River increases significantly during the study period. In the future, the vegetation will still show a spatial distribution pattern of high around the two rivers and low at the edge of Ejina Oasis. The lower reaches of the surrounding areas of the tail lake are close to or have reached the maximum recovery potential. The vegetation enhancement potential of Badaohe to Swan Lake channel, Qidaohe tail channel, Sidaohe and Liudaohe tail channel and the west of Xihe lower section are great. [ABSTRACT FROM AUTHOR]

Land cover change is a direct driver of the carbon cycle in terrestrial ecosystem. In order to evaluate the carbon sequestration ability of the terrestrial ecosystem and explore the response relationship between land cover change and ecosystem carbon storage, based on InVEST model, the paper analyzed and predicted the temporal and spatial variation characteristics of carbon storage in Heihe River Basin. We quantified the influence of land cover change to the ecosystem carbon storage. The result shows as follows: The carbon storages in 1992, 2000, 2010 and 2020 are 764.49 million tons, 769.85 million tons, 773.31 million tons and 769.90 million tons respectively in Heihe River Basin, showing increasing first and then decreasing. The carbon storage has increased 5.41 million tons from 1992 to 2020 and decreased from the southwest to the northeast in space. The main reasons for the increase of carbon storage in the basin are the conversion of bare areas to cropland, sparse vegetation and grassland, the conversion of mosaic vegetation and grassland to forest, which make the increases of vegetation coverage and canopy density. [ABSTRACT FROM AUTHOR]

Based on domestic high-resolution remote sensing images, this paper carried out remote sensing monitoring of human activities in the scope of management and protection of hydraulic engineering works and downstream flood channels. On this basis, it analyzed the interactive relationship between human activities and the security of engineering flood control and proposed the risk assessment methods and models of human activities in hydraulic engineering works. Lastly, an application demonstration was shown by using Hekoucun Reservoir as an example. The monitoring results show that there are less human activities within the scope of the reservoir management and protection, but more human activities within the scope of the downstream Qinhe River management and protection. After the completion and acceptance of the project, human activities within the scope of the reservoir management and protection are decreased, while human activities within the scope of the downstream Qinhe River management and protection are increased. Before and after the flood season, there is no significant change in human activities within the scope of the reservoir management and protection, but in the scope of downstream Qinhe River management and protection, human activities are affected by heavy rainfall, and the occupied area changed. After calculation, the average interference index of the reservoir is 17.6, and that of Qinhe River is 67.22. After the completion and acceptance of the project, the interference index of the reservoir is decreased significantly, while the interference index of Qinhe River is increased slightly. Before and after the flood season, the interference index of human activities in Hekoucun Reservoir remains unchanged, and the interference index of Qinhe River human activity fluctuates to a certain extent. Application demonstration proves that remote sensing technology can effectively monitor the risk sources of human activities in water conservancy projects during operation, and can quantitatively assess the impact of risk sources of human activities on flood control of hydraulic engineering works. [ABSTRACT FROM AUTHOR]

Reservoir sedimentation has always been a problem that troubles the reservoir management department. Scientifically and reasonably utilizing reservoir operation methods to achieve efficient sediment reduction in reservoirs is an effective means to solve reservoir sedimentation. This paper analyzed the reservoir sediment regulation of the Haibowan Reservoir on the Yellow River from 2019 to 2022, and combined the inflow and outflow water and sediment data during the flood season since the construction of the reservoir to carry out research on efficient sediment reduction of the Haibowan Reservoir. The research results indicate that: a) the goal of reservoir sediment reduction is achieved in 2019, 2020 and 2022, and the balance of erosion and sedimentation is basically achieved in 2019, while the sediment reduction effect is better in 2020 and 2022. b) The water level in front of the dam is a key factor affecting the sediment reduction of the Haibowan Reservoir, while the inflow water and inflow sediment are secondary factors affecting the outflow sediment volume. By fitting the influencing factors, an empirical formula for sediment reduction from the Haibowan Reservoir is obtained. c) Different combinations of inflow water and sediment require different scheduling measures to achieve efficient sediment reduction in the reservoir. Efficient sediment reduction in the reservoir can only be achieved by reasonably matching the inflow water and sediment conditions and the water level in front of the dam. [ABSTRACT FROM AUTHOR]

The rainstorm and flood disaster caused by extreme weather events seriously threatens the safe operation of the reservoir. Starting from the concept of flood control of extreme thinking and bottom line thinking, the flood discharge capacity of the current project of Luhun Reservoir cannot meet the actual needs of excessive flood prevention in the future. By transplanting Huaihe River rainstorm occurred in August of 1975 and Zhengzhou rainstorm occurred in July of 2021 to Luhun Reservoir for flood simulation, this paper carried out the flood simulation analysis and coping strategy of Luhun Reservoir under the rainstorm transplantation scenario. The results show that the flood discharge capacity of the current Luhun Reservoir is insufficient, and the reservoir needs to build extra spillway; The construction quantity of Laohukou exit scheme of emergency spillway is slightly greater than that of Tanggou exit scheme, but the latter involves more difficult personnel relocation, so it is inclined to the former. The extraordinary spillway design scale and scheme are proposed, and the design scale and scheme of the extraordinary spillway are optimized and improved through the model test. [ABSTRACT FROM AUTHOR]

Xiaolangdi Reservoir plays a crucial role within the flood control system of the middle and lower reaches of the Yellow River. It is of great significance for the flood control security of the Yellow River to maintain a large reservoir capacity for a long time and extend the op eration period of sediment containment. Based on the change of water and sediment condition and the analysis of operation practice of Xia olangdi Reservoir, this paper put forward the operation mode of reducing sediment of Xiaolangdi Reservoir. In the preflood season, consider ing the sedimentation of the downstream channel and the flow capacity of the main channel, the use of large flow process to reduce the water level and discharge sediment is carried out as far as possible, and the newly added sediment in the reservoir channel is washed out to restore the flow capacity of the channel and maintain the efficient sand transport channel in the reservoir area. After the operation of the reservoir, the water level should not be higher than the larger beach surface of the reservoir, and the use of channel transport and regulation can effectively reduce the sedimentation of the beach surface. In the postflood season, on the premise of ensuring the safety of flood control, according to the situation of sediment coming from the upstream, the reservoir water level is stored above the beach near the HH37 section as soon as pos sible, and the sediment is temporarily transferred above the HH37 section to slow down the sedimentation of the beach surface. [ABSTRACT FROM AUTHOR]

Based on the panel data of each city and prefecture in Qinghai Province from 2007 to 2021, the index system was built. The paper used AHP-entropy weight TOPSIS to measure the high quality development level of Qinghai Province and made a comprehensive analysis with the help of coupling coordination degree, standard deviation ellipse, Dagum Gini coefficient, Kernel function and other models, the overall coordination and spatial-temporal evolution characteristics were comprehensively analyzed, and the obstacle factors were identified. The results show that the average high-quality development index of Qinghai Province from 2007 to 2021 is 0.434 1, which is at a medium level. Among the cities and prefectures, Xining City has the highest high-quality development level, with an average index value of 0.568 4. The high quality development level of Qinghai Province is in a state of fluctuating improvement. The largest contribution from the five dimensions is innovation and development, with an average contribution of 29.43%. The coordination of the high-quality development system in Qinghai Province is at the level of imbalance, with an average coordination index of 0.290 7. The level of high-quality development presents spatial imbalance and regional differences, and the differences mainly come from inter-regional differences, with an average contribution rate of 50.87%. The criterion-level obstacle factor that affects the high-quality development level of Qinghai Province is innovation and development (the average degree of obstacle is 28.75%), and the largest index-level obstacle factor is scientific and technological investment (the average degree of obstacle is 8.95%). [ABSTRACT FROM AUTHOR]

In order to improve the feasibility and comprehensiveness of the application of BIM lightweight technology in water conservancy projects, this paper analyzed and summarized the mainstream BIM lightweight technology. Taking Miyun reservoir reconstruction and elimination of hazards project as an example, it put forward the application route of water conservancy project BIM lightweight technology, and improved the application effects of BIM lightweight technology in different construction stages. In the design stage, the comprehensive use of model reduction optimization, rendering optimization and BIM lightweight collaborative design platform can greatly improve the efficiency of three-dimensional model design; By using the BIM lightweight engine to transmit the BIM design model to the construction stage and establishing a BIM lightweight construction management platform, the quality of construction management can be effectively improved, ensuring that the project is completed on time and with quality. For the current status of BIM lightweight technology, this paper puts forward suggestions for future development: BIM lightweight technology should be able to integrate a variety of water conservancy engineering industry characteristics of data, improve the BIM specifications and standards, so that the BIM lightweight application system is more standardized and scientific. [ABSTRACT FROM AUTHOR]

Due to the influence of environment and other factors, there are often abnormal data in dam monitoring data and the detection of abnormal data plays an indispensable role in the normal operation of the dam. However, the accuracy of traditional anomaly detection algorithms for dam monitoring data often fails to meet the requirements. In this paper, an anomaly detection algorithm based on Prophet GMM was proposed. The better fitting performance of Prophet algorithm was used to fit the dam data and the residual sequence was obtained from the fitting data and the actual data. Then, the residual sequence was clustered by GMM algorithm to accurately identify the abnormal value. The test results show that the method proposed in this paper can accurately identify outliers for different types of dam monitoring data. Compared with the traditional detection algorithm, it has significantly improved the detection indicators of precision, recall and accuracy. [ABSTRACT FROM AUTHOR]

In order to improve the flood disaster prevention and mitigation capacity, taking Henan Province as the study area, the paper built a comprehensive flood disaster bearing capacity evaluation index system covering disaster prevention capacity, disaster resistance capacity, disaster relief capacity and recovery capacity, and assessed the comprehensive flood disaster bearing capacity of Henan Province by using AHP-entropy combination assignment method and comprehensive evaluation index model. The results show that a) the comprehensive flood disaster bearing capacity of Henan Province shows certain regular changes, and the distribution characteristics of comprehensive disaster bearing capacity and disaster relief capacity are basically the same, overall the central region > southwest region > northeast region > east region > southeast region northwest region. South region has the strongest disaster prevention capacity, while the north and central regions have weaker disaster prevention capacity; cities in the southwest-northeast regions have stronger disaster resilience, while cities in the north- west-southeast regions are weaker; recovery capacity basically decreases from northwest to southeast. The area with medium and above comprehensive disaster-bearing capacity accounts for 66.67% of the total area, and the area with lower medium capacity accounts for 33.33% of the total area. b) In terms of the disaster-bearing capacity of each city (pilot area), Xinyang City has the strongest disaster prevention caрасity and the pilot area of Jiyuan has the weakest disaster prevention capacity and disaster relief capacity. Zhengzhou City has the strongest disaster prevention capacity, disaster relief capacity and recovery capacity, and Sanmenxia City has the weakest disaster relief capacity. Zhumadian City has the weakest recovery capacity. The comprehensive disaster bearing capacity of flood disaster in Henan Province is at a medium and low level on the whole, so it is necessary to formulate reasonable strategies to improve the comprehensive disaster bearing capacity of flood disaster. [ABSTRACT FROM AUTHOR]

In 2021, the Yellow River experienced the most serious autumn flood since 1949. The Sanmenxia Reservoir played an important role in the autumn flood control, but there was 1.04 billion cubic meters difference between the inflow and outflow of the flood volume. In order to identify the cause of the above water imbalance, this paper took Tongguan-Sanmenxia reach as the study area, and digital elevation model, land use, soil type, meteorological and hydrological data were used to drive a HEC-HMS distributed hydrological model for flood processes simulation. The results show that the bias of simulated flood peak in 11 floods are all less than 20.0%, the average coefficient of determination of the simulations is 0.725, and the pass rate of the results is 90.9%. The model accurately simulates the water inflow process in the Tongguan-Sanmenxia reach during the autumn flood season in 2021, and the contribution of different tributaries to the total flood amount of the reach is quantified. [ABSTRACT FROM AUTHOR]

Lowering water level and scouring is an effective measure to restore reservoir capacity. Since 2011, Wanjiazhai Reservoir has used this measure for many times in the period of sediment discharge and achieved a good effect of sediment discharge. Based on the measured hydrological data, this paper analyzed the effectiveness and influencing factors of lowering water level and scouring of the Wanjiazhai Reservoir since 2011. The results show that a total of 717.3 million tons of sediment has been discharged by the reservoir from 2011 to 2021 (excluding 2016). The sediment discharge is mainly concentrated during the sediment discharge period. From 2018 to 2020 water is abundant, the time of lowering the water level and scouring of the reservoir is long and a total of 484 million tons of sediment is discharged during the three years. There are many factors affecting sediment discharge in reservoirs, and long-term large inflows are beneficial to reservoir sediment discharge. When the operational water level is decreased, the storage is decreased, the scouring distance along the channel is longer, and the backwater sand transport distance shortened, which is conducive to improving the sediment discharge effect of the reservoir. Through regression analysis, the relationship between the sediment transport rate and the main influencing factors under different water levels is established. [ABSTRACT FROM AUTHOR]

In order to scientifically identify the characteristics of drought and wetness in the Yellow River and the coping capacity, this paper put forward a judgment method of continuous wet years and continuous dry years, used the Standardized Runoff Index (SRI) and the Standardized Drought-Wetness Abrupt Alteration Index (SDWAI) to identify the characteristics of runoff changes at Lijin Station of the Yellow River from 1956 to 2020, and analyzed the role of reservoir operation in coping with the drought-wetness abrupt alteration events and continuous dry years. The results show that on a monthly scale, the SRI assessment results of Lijin Station are mainly normal to moderate drought, with only a few drought-wetness abrupt alteration events which mainly happen during the transition period between flood season and non-flood sea-son. On an annual scale, more than 60% of the years are assessed as normal or light drought, and the SRI assessment results are consistent with the assessment results using anomaly value. On a multi-year scale, there are 3 continuous wet years and 2 continuous dry years at Lijin Station, and the continuous dry years last for a long time. With the enhancement of reservoir regulation and storage capacity, drought-wetness abrupt alteration events are handled well, but the capacity to cope with continuous dry years is insufficient. [ABSTRACT FROM AUTHOR]

By exploring the coupling and coordination relationship between high-quality agricultural development and ecological environment in the Yellow River Basin, and providing scientific reference for ecological protection and high-quality development in the Yellow River Ba- sin, this paper took nine provinces in the Yellow River Basin as the research object, and based on the panel data from 2012 to 2020, adopted the entropy value method, coupling coordination degree, spatial autocorrelation and spatial econometric model to study the coupling and coordination characteristics of high-quality agricultural development and ecological environment, and analyzed the spatial and temporal pattern evolution and driving factors of the coupling and coordination degree between them. The results show that the high-quality development level of agriculture and the ecological environment level in the Yellow River Basin are both on the rise, the regional pattern of the former is mainly "high in the upper and lower reaches and low in the middle reaches". The regional pattern of the latter is mainly "high in the middle and lower reaches and low in the upper reaches". The degree of coupling coordination between high-quality agricultural development and ecological environment is at a relatively low level, higher coupling coordination in the downstream than that of the middle and upper stream, there is a significant spatial agglomeration effect. Scientific and technological innovation and agricultural products trade play a significant role in the coupling and coordination level of high-quality agricultural development and ecological environment in the province (autonomous region), environmental regulation, scientific and technological innovation and agricultural trade have a significant positive space spillover effect, however, the spatial influence degree of each factor is different. In order to promote the improvement of coupling and coordination degree, the following suggestions are put forward; formulating development strategies in accordance with local conditions, strengthening interregional coordination and cooperation, and correctly playing the role of government and market. [ABSTRACT FROM AUTHOR]

In order to provide theoretical support and decision-making basis for improving the level of industrial green development in the Yellow River Basin and promoting the transformation and building industrial green development in the Yellow River Basin, the panel data of nine provinces (regions) in the Yellow River Basin from 2012 to 2021 were used to calculate the level of industrial green development in the Yellow River Basin by using entropy weight-TOPSIS model. The differences were analyzed from spatial distribution, temporal characteristics and provincial levels, and the obstacle factor diagnosis model was used to explore the main obstacle factors affecting the green industrial development in the Yellow River Basin. The results show that the level of industrial green development in the Yellow River Basin shows an over- all upward trend from 2012 to 2021, with the value increasing from 0.378 in 2012 to 0.498 in 2021. The main obstacles to green industrial development in the Yellow River Basin are industrial environmental control and industrial innovation. The main obstacle factors are the proportion of industrial pollution investment in industrial added value, industrial labor productivity, the proportion of industrial wastewater treatment funds in industrial pollution control investment, the number of valid invention patents per household of industrial enterprises above designated size, and the level of innovation capital investment. Finally, the paper put forward some suggestions to improve the level of industrial green development in the Yellow River Basin from three aspects of optimizing industrial structure, strengthening environmental governance and building green innovation system. [ABSTRACT FROM AUTHOR]

In order to quantitatively evaluate the impact of inter-industry water rights transfer on economy and society in the main stream of the Yellow River in Inner Mongolia, the paper analyzed the impact of water rights transfer on agriculture, and the impact of water rights transfer on water use, production and operation, annual income, people's livelihood and economy of all industrial enterprises. The results show that the transfer of inter-industry water rights in the main stream of the Yellow River in Inner Mongolia in 2019-2021 has driven the total investment of industrial projects to 599.58 billion Yuan, created 122 145 new jobs, the gross regional product is 44.709 billion Yuan, the industrial added value is 238.821 billion Yuan, the annual tax revenue is 19.47 billion Yuan, the newly paved road area is 13.161 7 million km², and the new green area is 30.995 million km². The agricultural output value and farmers' income have been significantly increased, local livelihood issues have been effectively solved, and ecological protection and social and economic development along the Yellow River have been promoted. The transfer of water rights between industries in the main stream of the Yellow River in Inner Mongolia has alleviated the bottleneck of water resources of industrial enterprises along the Yellow River, realized the multi-win of farmers' production increase, economic efficiency increase and ecological restoration, and provided strong support for ecological protection and high-quality development of the Yellow River Basin. [ABSTRACT FROM AUTHOR]

In order to improve the carbonation resistance of coated concrete under ultraviolet irradiation, the cement-based crystalline coating and polyurethane coating were modified by introducing different amounts of rutile nano-TiO₂. The rapid carbonation test results show that ultraviolet radiation will weaken the carbonation resistance of the coated concrete to a certain extent. With the increase of nano-TiO₂, content, the anti-carbonation performance of the two coated concretes under ultraviolet radiation has been improved to varying degrees, and with the increase of nano-TiO₂ content, the anti-carbonation performance shows a trend of first improving and then decreasing, among which the optimal content of nano-TiO₂, in cement-based crystalline coating is 2%, the optimal content of nano-TiO₂, in polyurethane coating is 1%-2%, and the anti-carbonation performance of polyurethane coating is most obvious under ultraviolet light. The results of this paper can provide engineering guidance for the improvement of concrete coatings in service under ultraviolet environment. [ABSTRACT FROM AUTHOR]

Accurate prediction of evaporation is of great significance for the rational development and utilization of water resources, the study of drought and flood trends, and the estimation of crop irrigation water consumption. In this paper, 7 meteorological data observed by 14 ground international exchange stations in northern China were selected. Based on the time convolution network (TCN) model, the K-nearest neighbor (KNN) algorithm was used to screen the spatial factors of pan evaporation. The KNN-TCN pan evaporation prediction model was built and the average absolute error, root mean square error and coefficient of determination were used to evaluate the evaporation prediction ac- curacy of the target site. The results show that a) the prediction results of KNN-TCN model are significantly better than that of LSTM model. b) Compared with the basic TCN model, the determination coefficient of KNN-TCN model is increased by 2.52%, and the mean absolute error and root mean square error are reduced by 23.97% and 13.06%, respectively. [ABSTRACT FROM AUTHOR]

In order to promote the implementation of the action of deep water saving and control in the Yellow River Basin and improve the level of intensive utilization of water resources in Shaanxi Province, this paper discussed the definition of deep water saving, using the Fuzzy Analytic Hierarchy Process (FAHP) to establish the evaluation index system of deep water saving level, evaluated the deep water saving level of cities in the Yellow River Basin of Shaanxi Province, put forward the existing problems and countermeasures, and calculated the deep water saving potential according to the deep water saving goal, which had theoretical support for the implementation of deep water saving in Shaanxi Province. The results show that in the current year, the level of deep water saving in Xi'an, Xianyang, Yan'an, Tongchuan, Baoji, Hancheng, Yangling, Yulin, Shangluo and Xixian New District is strong, and the level of deep water saving in Weinan is general. The deep water saving potential of the Yellow River Basin in Shaanxi Province during the 14th Five-Year Plan period is 323.9 million m³, which can increase the water saving potential of 82.7 million m³ compared with the general water saving situation [ABSTRACT FROM AUTHOR]

The Yangtze River Economic Belt is the leading demonstration belt for ecological civilization building. It is of great significance for the sustainable development of regional ecological environment to explore the temporal and spatial changes of ecosystem services and the trade-off/synergy relationships. Based on methods such as land use transfer matrix, modified equivalent factor method, sensitivity index, spatial autocorrelation and Pearson correlation coefficient, this paper quantitatively analyzed the land use situation and its spatial-temporal response to ecosystem services in the Yangtze River Economic Belt from 2000 to 2020, and explored the trade-off/synergistic relationship between various ecosystem services. The results show that during the study period, the land use types in the Yangtze River Economic Belt are mainly forest land, cultivated land and grassland, and the largest area transferred out and transferred into area are cultivated land and forest land respectively. The ecosystem service value of the Yangtze River Economic Belt increases from 7 019.501 billion Yuan in 2000 to 7 042.623 billion Yuan in 2020, with a growth rate of 0.33%. Ecosystem services are mainly hydrological regulation, climate regulation, soil conservation and gas regulation services. The spatial distribution pattern of ecosystem service value in the Yangtze River Economic Belt is as follows: upstream > middle reaches > downstream. The agglomeration effect of the spatial distribution of ecosystem service value in the study area is significant, with high-high agglomeration areas concentrated in upstream areas, low-low agglomeration areas concentrated in downstream Jiangsu Province and Anhui Province, and low-high agglomeration areas concentrated in Panzhihua City, Sichuan Province. The synergy relationship is the dominant relationship of ecosystem services in the Yangtze River Economic Belt, with a synergy rate of 63.64%. [ABSTRACT FROM AUTHOR]

In order to reduce the risk of water shortage of Qinhe River Basin, this paper took Qinhe River Basin as the research object, estimated the blue and green water resources in Qinhe River Basin from 2010 to 2016 based on the output results of the SWAT model, calculated the blue and green water scarcity index through the blue and green water footprint and the blue and green water availability, and quantitatively evaluated the blue and green water shortage situation in Qinhe River Basin by dividing four risk levels of blue and green water shortage. The results show that: a) The average annual blue water resources in Qinhe River Basin are 910 million m³, accounting for 12.0% of the total water resources, and the average annual green water resources are 6.69 billion m³, accounting for 88.0% of the total water resources, and the main component of water resources in Qinhe River Basin is green water resources; b) Under the annual scale, the blue water shortage index of most molecular basins in Qinhe River is greater than 1.0, and the risk level of blue water shortage is relatively serious risk, especially in Jiaozuo City in the downstream area; c) Under the annual scale, the index of green water scarcity in each subbasin of Qinhe River shows some differences, the average annual green water shortage index in most sub-basins is in the range of 0.5-1.0, and the green water shortage faces moderate risk; On the whole, the risk level of green water shortage is lower than that of blue water shortage. Based on the analysis of water shortage indexes of blue water and green water, it put forward suggestions on reducing the water safety risk of Qinhe River Basin. [ABSTRACT FROM AUTHOR]

Under the rapid urbanization and industrialization, the risk of natural disasters in cities is increasingly exposed, especially the issue of rain-induced flood has become increasingly prominent. In view of the rain-induced flood that has occurred in Gongyi City in recent years, a study on the risk of rain-induced flood in Gongyi City has been carried out in order to provide a scientific basis for the city's disaster prevention and mitigation work. Based on the natural disaster risk assessment theory, this paper built a rain-induced flood risk model with the risk of disaster factors, the risk of disaster-pregnant environment, the vulnerability of disaster-bearing bodies and the ability to prevent and reduce disasters as evaluation indicators. Starting from the above, a total of 14 index factors were selected for quantitative analysis, and the SCS model (Soil Conservation Service) and GIS spatial analysis functions were used to finally obtain the comprehensive risk zoning map of rain and flood disasters in Gongyi City. The results show that Mihe Town, Huiguo Town, Zhitian Town and Xiaoyi Sub-District of Gongyi City are more dangerous. The risk of pregnancy in disaster environment in the north, west and east areas include Heluo Town, Xiaoyi Sub-District, Huiguo Town, Zhitian Town and Mihe Town is higher. The disaster-bearing bodies in the western and central parts are more vulnerable, including Huiguo Town, Zhitian Town and Zhanjie Town. The overall disaster prevention and mitigation capacity of the north is strong, including Zhanjie Town and Zijing Sub-District. In general, the overall risk level of rain-induced flood in Gongyi City is relatively higher, and the high-risk areas are mainly distributed in a belt-like structure in the north-central and western regions. [ABSTRACT FROM AUTHOR]

Evaporation is an essential link between surface energy balance and water balance, and high-cold regions are sensitive to climate change. However, there is a large amount of uncertainty in the evaporation prediction process in the high-cold areas, which poses severe challenges to scientifically analyzing the hydrological cycle changes and water resources management in river basins. Therefore, taking the source area of the Yellow River in the “high-cold region” as an example, this paper used five evaporation calculation models with different physical mechanisms (P-M, Har, J-H, Mak and P-T) to clarify the impact of model uncertainty on the prediction of potential evaporation in the basin. Secondly, by coupling the “evaporation calculation model, GCMs and RCPs” model, the impact of various uncertainties on the uncertainty of potential evaporation prediction in different future periods (short-term, medium-term, and long-term) was explored. The contribution of their independent and interactive effects to the uncertainty of potential evaporation prediction was separated using the variance analysis method. The results show that the potential evaporation model based on solar radiation and temperature is significantly greater than the potential evaporation model based on physical mechanism, and its annual potential evaporation difference is about 150 mm. The uncertainty of RCPs is the main factor leading to the uncertainty of evaporation prediction, accounting for about 65%, and the contribution of the interaction between multiple uncertainty sources to the uncertainty of evaporation prediction is particularly prominent in the “spring and winter” seasons. [ABSTRACT FROM AUTHOR]

In order to provide decision-making reference for promoting coordinative development of economy and ecology in the Yellow River Basin, this paper selected panel data from 2010 to 2020, built an indicator system from five levels of growth quality, resources consumption, environmental governance, social life, and scientific research and innovation, used the entropy weight comprehensive index method to evaluate the green development level of the upper reaches of the Yellow River and its four provinces and regions, and analyzed the temporal characteristics and regional differences of the green development level. The results show that from the perspective of temporal variation, the green development level of the upper reaches of the Yellow River has increased steadily since 2010, and by 2020, the criteria level scores are social life, resources consumption, scientific research innovation, growth quality and environmental governance. From the perspective of regional differences, the green development level of the four provinces and regions in the upper reaches of the Yellow River shows a stable and positive trend from 2010 to 2020, but there is still room for improvement. Inner Mongolia scores the highest (0.538) and Qinghai scores the lowest (0.346). From the perspective of internal differences, the weakness of green development in Inner Mongolia is the high consumption of resources. The level of social life and resources consumption in Ningxia needs to be improved. The quality of growth in Gansu is not high. Qinghai needs to improve the level of social life, scientific research innovation and environmental governance. Therefore, the upper Yellow River region should strengthen the quality of growth and environmental governance, implement differentiated measures to improve the level of green development and promote green transformation. [ABSTRACT FROM AUTHOR]

In order to solve the problem that the assessment method of urban water resources vulnerability too subjective and not taking into account the finite rationality of natural person and the psychological behavior characteristics of regret avoidance, which resulting in the distortion of the evaluation results, this paper proposed an urban water resources vulnerability assessment method based on OWA operator empowerment and regret theory. The DPSIR model was used to construct 29 evaluation indexes from the following five aspects including driving force, pressure, state, influence and response. OWA operator was used to reorder the decision data, which fully considered the location and size of data, so as to weaken the negative effect of extreme decision data on weight. The difference between the utility value of decision data and the ideal utility value in the regret theory was selected as the basis to evaluate the subjectivity of experts, so as to realize the objectification of the subjective data of decision making and improve the objectivity of the evaluation results. Finally, this paper evaluated the water resources vulnerability of Zhengzhou from 2017 to 2022, and compared the evaluation results with those of AHP and regret theory, OWA operator and fuzzy mathematics. The results show that the evaluation results of urban water resources vulnerability assessment method based on OWA operator empowerment and regret theory are basically consistent with the evaluation results of other methods, all of which are considered as severely vulnerable water resources in Zhengzhou City. However, the evaluation results of this method have less relative error and are more close to the actual situation, which can be better used for the assessment of urban water resources vulnerability. [ABSTRACT FROM AUTHOR]

The planting structure and spatial distribution of crops are the basis for the estimation of crop losses in flood disasters. In order to meet the accuracy requirements for rapid assessment of crop losses in flood disasters, it is urgent to build a real-time crop survey and disaster assessment method that combines remote sensing technology with ground surveys. Taking the rainstorm and flood disaster in Henan Province in 2021 as an example, this paper comprehensively used satellite remote sensing data and real ground object sample data obtained from field research to carry out a research on the fine classification of crops in Weihui City, Xinxiang, Henan Province, combined with the flood inundation duration calculation results based on remote sensing data, to assess the damage of crops in this flood disaster event in Weihui City. The results show that: a) The main types of flood disasters in Weihui City are high water level intrusion floods in rivers and waterlogging and stagnation in low-lying areas. b) The types of disaster-affected features are corn, the main crops, green forests around roads, and urban areas of Weihui City. The disaster assessment method for flood crops based on multi-source remote sensing data and real ground object samples proposed in this paper has high accuracy and timeliness. [ABSTRACT FROM AUTHOR]

Aqueduct is a typical space thin-walled structure, which is very sensitive to external temperature changes. Surface insulation measures can effectively improve the temperature stress distribution of the structure and prevent surface cracks. Although the calculation method of surface insulation capacity commonly used in dam construction is of reference significance to aqueduct insulation issue, it cannot be directly applied, so the aqueduct insulation issue needs to be studied separately. Therefore, based on the temperature load of aqueduct structure, this paper put forward a calculation method of aqueduct insulation design based on the temperature and temperature stress analysis of concrete structure. The calculation results show that the stress state of the groove body can be greatly improved by laying 5.0 cm thick polyurethane foam insulation material on the outer surface of the straight wall section and the arc section of 0°-45°. When the temperature rises, the inner wall circumferential and longitudinal tensile stress does not appear. When the temperature drops, the circumferential and longitudinal stress of the outer wall is reduced, and the stress state of the inner and outer walls of the groove body meets the design requirements. The project case study shows that the calculation method of thermal insulation design proposed in this paper can be applied to the thermal insulation design of aqueduct during operation, and then the key parameters of thermal insulation design such as laying range and insulation layer thickness can be determined. [ABSTRACT FROM AUTHOR]

The water quality data of the river basin has dual dependencies in time and space. Based on the fact that most of the existing water quality prediction models are only based on the time dimension and cannot make effective use of the spatial correlation of water quality, a spatiotemporal prediction model based on graph convolution neural network GCN and long short-term memory network LSTM was proposed in this paper. Firstly, the whole watershed was constructed into the topology of station-to-station connection, and the distance along the river between stations was taken as the indicator of connectivity between stations. For each input time, an independent GCN was used to capture the spatial relationship between stations, and then the temporal variation characteristics were captured by LSTM. Finally, the multi-step prediction results were obtained by multi-layer perceptron (MLP). The south source of Qiantang River was selected as the research object, multi step prediction experiments were carried out on three water quality prediction tasks of pH, DO and CODMn at 15 monitoring stations in the basin. The results show that in the three water quality prediction tasks, the average percentage error MAPE of GCN-LSTM model compared with LSTM model is decreased by 15.29%, 11.77% and 9.8% respectively. Compared with some classical time series models, the model proposed in this paper can better capture the spatial relationship of watershed water quality, improve the accuracy of water quality prediction and provide a new method for watershed water environment quality prediction. The connections between monitoring points have differences, and using distance to represent the strength of the connections between monitoring points can make water quality prediction results more accurate. [ABSTRACT FROM AUTHOR]

The series consistency of the natural runoff of the Yellow River is affected by the changes in the substratum due to human activities, which makes it difficult to support the water allocation under the current conditions of the basin. In this paper, we took the Wuding River, a typical tributary in the middle reaches of the Yellow River, which has a significant reduction in the natural runoff, as an example, and used the Mann-Kendall test and the double cumulative curve method of annual precipitation and runoff to discriminate the consistency of natural runoff series, and used the correlation method of precipitation and runoff to carry out the consistent correction under the current conditions of the sub-base. The correction result shows that the multi-year average natural runoff volume in the current lower mat condition of the Baijiachuan section is 958 million m³, which is 193 million m³ less than that of the result of the "second survey", with a reduction of 16.8%. Extending the method of this paper to the Yellow River Basin, the analysis shows that the natural runoff in the Yellow River Basin is 49 billion m³, which is 15.5% less than the 58 billion m³ in the natural period, and 8.4% less than the 53.48 billion m³ in the "second survey" basin. [ABSTRACT FROM AUTHOR]

Steel pipe lining is a common support method for hydraulic engineering tunnels. It is very important to apply advanced technology to carry out void detection of steel pipe lining for project quality evaluation. In this paper, the longitudinal wave reflection coefficients of the three interfaces between steel and water, concrete and air were calculated, and the amplitude and phase variation characteristics of the reflection coefficients with the incident angle were analyzed. Through theoretical analysis, a data processing and analysis method by using the amplitude ratio of ultrasonic multiple reflection waves to detect voids was proposed. Concrete models with a thickness of 1.6 cm and 3.0 cm steel plates were made, and the models were tested with two types of 2.5 MHz probes. The results show that the reflected wave amplitude in the void area is relatively higher, which verifies the theoretical results of this paper. The pulse echo method is used for comparative detection, and the results show that the method has a certain detection effect. Since the actual impedance of the concrete cemented with the bottom of the steel plate is relatively lower, it is recommended to divide a larger detection unit for detection of a large amount of data to improve the accuraey of void discrimination.. [ABSTRACT FROM AUTHOR]

For measuring the effectiveness of a happy river building, searching the problems faced by a happy river building and exploring a new path for a happy river building within the framework of economic and social development, this paper explored the multi-level connotation of happiness through river ethics, Marxist view of happiness and Xi Jinping thought on ecological civilization. This paper, basing on analyzing the development direction and specific requirements of the modernization of the national governance system and governance capacity, focusing on the characteristics of social governance such as process, harmonization, diversity and interaction, simultaneously focusing on the modernization degree of governance system and governance capacity and governance effectiveness from the four perspectives of structure, process, function and service, built the evaluation index system of a happy river, which could provide a new method and path for comprehensive evaluation of regional water governance work from a broader perspective. [ABSTRACT FROM AUTHOR]

In order to reveal the annual variation of the distribution of water, heat and salt in the dry soil in the gullied rolling loess area after continuous mulching for many years and provide reference for further research on improving the water, heat and salt status of dry layer soil, the paper took jujube woodland that covering with the white film (colorless transparent plastic film), black film (black bovine felt) and bared ground control test plots continuously for 5 years in Mizhi County, Northern Shaanxi Province as the research object, the paper analyzed the migration and changes of water, temperature and salt in different soil layers during the year based on the location monitoring data of soil water content, temperature and conductivity by GS3 sensors with buried depths of 5, 15, 30, 50, 75, 100, 125 and 150 cm. The results show that a) after continuous film mulching for 5 years, the water content of 0-150 cm soil layer is significantly higher than that of bared soil, especially the water storage of 0-60 cm soil layer is significantly increased, and the black film mulching has a better effect on rain collection and water conservation than that of the white film mulching. b) The soil temperature in each soil layer of the two mulching plots is significantly higher than that of the bared plots. The white film mulching has a better thermal insulation effect in the cold period, and the black film mulching has a certain regulatory effect on the soil temperature in the 0-60 cm tilling layer in the high temperature period. c) After many years of film mulching, the phenomenon of surface soil salt accumulation will occur, but it will not cause soil secondary salinization. d) There is a significant positive correlation between soil water and salt in each plot at different stages, and the correlation between water and salt is relatively weaker in the plot covered with black film, while the correlation between soil water and heat and salt is significantly different. The two kinds of film mulch have different regulatory effects on soil water, heat and salt at different stages. [ABSTRACT FROM AUTHOR]

The virtual water trade in a region is affected by both natural factors and human activities. In order to quantitatively study the influence of human activities to the virtual water trade, a new quantitative comparative analysis method was proposed in this paper. By adjusting the natural climate factors into a uniform standard, this paper quantitatively analyzed the impact of the increase and decrease of external water diversion and the strictest water resources management policies on the virtual water trade in agricultural and industrial sectors by year and inter-year. Taking Shandong Province as an example, this study applied this method to make a quantitative analysis of virtual water trade in Shandong Province in the past 20 years. The results show that with the development of economy, the net output curves of agricultural and industrial virtual water are U-shaped and irregular inverted U-shaped, respectively. Virtual net water output can adversely affect the local water environment. In 1997, when the Yellow River stopped flowing, the decrease of water diversion reduced the net virtual water output of agriculture and industry by 20.13% and 49.67%, respectively. In 2017, the input of the South-to-North Water Diversion Project increased the net virtual water output of agriculture and industry by 1.32% and 41.99%, respectively, compared with that without the diversion, while the implementation of the strictest water resources management policy reduced it by 10.01% and 20.39%, respectively. [ABSTRACT FROM AUTHOR]

In order to assess the water resources carrying capacity of the Gansu section of the Yellow River Basin, this paper chose a set of 20 evaluation indicators initially, targeting four distinct secondary regions. Through an analytical process involving sensitivity and correlation assessments, seven indicators that exhibited low sensitivity and high correlation were pruned, culminating in a refined set of 13 indicators. These indicators were systematically organized into four sub-systems of water resources, societal factors, economic aspects, and ecological environment. The composite scores were derived by integrating the entropy weight method with the TOPSIS model. Furthermore, a barrier factor diagnosis model was applied to evaluate the water resources carrying capacity across the four secondary regions. The findings reveal spatial variations in carrying capacity, with the area above Longyangxia station demonstrating the highest capacity, followed by the sections from Longyangxia station to Lanzhou and from Lanzhou to Hekouzhen station, and the lowest capacity observed in the section from Longmen to Sanmenxia station. In terms of temporal trends, barring the area above Longyangxia station, a steady rise in carrying capacity is observed in the remaining three regions. Key factors impeding the water resources carrying capacity in the Gansu section of the Yellow River Basin encompass per capita water availability, water production index, per capita water supply, population density, urbanization rate, and the rate of water usage for ecological environments. Strategic planning of water resources distribution, restructuring water consumption patterns, and synchronizing water resources carrying capacity with economic growth are instrumental in enhancing and sustaining the carrying capacity of the Gansu section of the Yellow River Basin. [ABSTRACT FROM AUTHOR]

Dam-break risk standards are the basis for dam managers to make risk decisions. However, as one of the important contents of dam break risk standard, there is no unified environmental risk standard at present. This paper used the research ideas of ecosystem service value and equivalent factor method in ecological economics for reference, and quantified the environmental value. ALARP criterion and F-N curve were used to effectively link environmental standards with existing standards. Considering the differences of environment and economy in different regions of China, the risk preference matrix was built, and the risk preference of each region was determined, so as to formulate the environmental risk standard in China. Taking Luhun Reservoir in Henan Province as an example, the application of this method was illustrated. [ABSTRACT FROM AUTHOR]