In order to provide references for landslide hazard prevention and research on the sensitivity of landslide-causing factors, the Longyangxia-Jishixia section of the upper Yellow River basin was selected as the study area, and 16 factors such as elevation, slope, terrain roughness and lithology were taken as typical landslide hazard factors. The collinearity test was carried out by Spearman correlation coefficient method to select landslide hazard factors with strong correlation. GIS was used to reclassify landslide disaster-causing factors and analyze their weights with geographic detectors. The geographic detection model results were coupled with random forest model to obtain landslide prediction probabilities under different causative factors. ROC curve was used to verify the accuracy of prediction results. The results indicate that a）the explanatory power of the interaction between causative factors is greater than that of individual factors, with the synergistic effect of elevation and other topographic parameters being particularly significant. b）The importance of drainage density, topographic roughness, and profile curvature is nearly zero, suggesting that these features may not have a direct or significant correlation with landslide occurrence. c）There are notable differences in the contribution of causative factors to the prediction results, with the elevation-slope combination being the core driving unit for landslide development in the study area. d）The AUC value ofrandom forest model has achieved 0.93, indicating strong classification performance.

In order to clarify the groundwater quality evolution characteristics and the sources of groundwater chemical components in the saline irrigation area in western Jilin, the groundwater quality monitoring data from 2012-2014 and 2019-2020 were selected, and mathematical statistics, graphical method, entropy-weighted Bayesian, factor analysis, and Absolute Factor Score-Multiple Linear Regression (APCS-MLR) model were used to carry out the research on groundwater chemical characteristics, water quality evaluation and hydrochemical components traceability analysis in western Jilin irrigation area. The results show that:Fe, F, Mn and tri-nitrogen compounds in the irrigation area and its surrounding areas are seriously exceeded. The water chemistry type is mainly weak alkaline water of the HCO^-₃-Na⁺-Ca²⁺ type, affected by the dissolution and filtration of rocks and evaporation-crystallization, and the long-term irrigation and drainage salt-washing improves salinization of the irrigation area and its surrounding areas. During the research period, the salinization of the irrigation area and its surrounding areas diving Ⅳ,Ⅴ water proportion increased by a total of 5.3 percentage points, Ⅳ,Ⅴ water proportion in the pressurized water decreased by a total of 4.0 percentage points. Dissolved filtration-secondary enrichment effect on groundwater quality is the most significant, so that the concentration of soluble ions in the water, TDS, total hardness and other components of the water increased. Saline and alkaline development of paddy field irrigation area leads to increased regional agricultural activities on the impact of the chemical components of groundwater.

In order to explore the influencing factors and spatial differences of the green development of agriculture (GDA) in the Yellow River Basin (YRB), and to provide theoretical support and decision-making basis for the high-quality development of agriculture in the YRB, an evaluation index system for the level of GDA was established, which included three dimensions of high efficiency of development, ecological friendliness and resources conservation. Based on the panel data of 68 prefecture-level cities in the YRB from 2011 to 2021, the global entropy method (GEM) was applied to assess the level of GDA in the YRB, and the Moran index was used to analyze the spatial and temporal patterns of its differentiation. On this basis, six indicators were set up in economic, social and natural aspects, including industrial structure, planting structure, industrialization level, urbanization level, topographic relief and annual precipitation, and a multi-scale geographically weighted regression (MGWR) model was used to empirically analyze the influencing factors of the GDA in the YRB and its spatial differences. The results show that a) the level of GDA in the YRB shows an upward trend from 2011 to 2021, but the overall level at the end of the study period is still low, with the level of GDA in the lower reaches significantly higher than that in the middle and upper reaches, the development of efficient dimensions in the upper reaches and lower reaches showing a clear upward trend, and the ecologically friendly and resources-saving dimensions showing a smaller increase in the study period. b) There is an obvious positive spatial correlation between the level of GDA in the YRB, with a relatively large number of H-H agglomeration and L-L agglomeration prefecture-level cities. c) The spatial heterogeneity of the factors influencing the GDA is significant and the intensity of influence is different, among which the spatial differences in the influence of industrial structure, planting structure, industrialization level and topographic relief are small and the spatial difference in the influence of urbanization and annual precipitation is large. Industrial structure, industrialization level and topographic relief have negative effects, while planting structure, urbanization level and annual precipitation have positive effects. The intensity of influence is topographic relief > industrialization level > urbanization level > industrial structure > planting structure > annual precipitation. Some suggestions are put forward, such as changing the concept of agricultural development, strengthening regional cooperation and implementing differentiated agricultural green development strategies.

In order to explore the realistic path of new quality productivity to empower urban economic resilience in the Yellow River Basin, and provide a reference for the implementation of the major national strategy of ecological protection and high-quality development in the Yellow River Basin, based on the panel data of 99 sample cities in the nine provinces (autonomous regions) of the Yellow River Basin from 2011 to 2022, the entropy method was adopted to measure the level of new quality productivity and the urban economic resilience index. Moreover, the two-way fixed effect model and the mediating mechanism model were used to empirically analyze the impact of new quality productivity on the urban economic resilience of the Yellow River Basin and its mechanism of action. The results show that on the whole, the new quality productivity has a significant role in promoting the urban economic resilience of the Yellow River Basin, and its internal mechanism is to promote the upgrading of industrial structure and improve the level of infrastructure construction. The effect of new quality productivity is heterogeneous, especially in the middle reaches of the Yellow River Basin, small-scale and high-intensity environmental regulation cities are stronger. Some policy suggestions are proposed, such as actively cultivating and developing new quality productive forces, promoting the upgrading of industrial structure in the Yellow River Basin and implementing differentiated regional development strategies.

Concrete face rockfill dams (CFRDs) are widely utilized in water conservancy and hydropower engineering due to their excellent durability, strong impermeability, and cost-effectiveness. However, their seismic safety during service has raised significant concerns. In this study, a concrete face rockfill dam located on the upper reaches of the Yellow River was selected as the research object. Based on the structural characteristics of the dam and geological conditions, a three-dimensional numerical model was established to simulate the dam’s dynamic response under seismic action by integrating the Duncan-Chang model and the concrete damage plasticity constitutive model. Through this model, the dynamic responses of the dam under varying seismic intensities were analyzed, revealing the evolution of stress distribution and structural deformation characteristics. The results indicate that the critical zones prone to transverse damage under seismic action are located at two-fifths of the total height of the concrete face and the toe slab. Furthermore, based on the computational results, the correlation between failure variables and structural damage patterns under seismic action was investigated, and vulnerability curves under different seismic intensity levels were plotted. The findings demonstrate that with the increase of  seismic intensity, the vulnerability curves shows a rightward shift trend, and the failure probability of the dam body rises significantly.

In order to explore the development level and regional differences of new-quality-productivity in the nine provinces (regions) of the Yellow River Basin and provide a reference for the high-quality-development of new-quality-productivity in the Yellow River Basin, this paper built an evaluation index system of new-quality-productivity development level from the three dimensions of new workers, new labor objects and new labor materials. Based on the panel data from 2013 to 2022, the entropy value method was used to measure the development level of new-quality-productivity in the nine provinces (regions) of the Yellow River Basin, and the nuclear density estimation, σ convergence test and β convergence test, spatial correlation analysis and diagnosis of main obstacle factors were carried out. The results show that a) from 2013 to 2022, the development level of new-quality-productivity in the nine provinces (regions) of the Yellow River Basin shows an increasing trend year by year, among which Qinghai and Gansu have relatively low development level of new-quality-productivity, while Shandong and Shaanxi have relatively high development level of new-quality-productivity. b) There are obvious differences in the development level of new-quality-productivity in the upper, middle and lower reaches of the Yellow River, among which the lower reaches of the Yellow River is always much higher than that in the upper and middle reaches, and the upper reaches of the Yellow River is always lower than that in the middle and lower reaches, but the difference among provinces (regions) is decreasing, the phenomenon of multi-polarization is weakening, and there is a “catch-up effect” and the development of new-quality-productivity in each province (region) will be affected by neighboring provinces (regions). c) From the three dimensions of the development of new-quality-productivity, the new labor object dimension is the “weak side” that needs to be strengthened in the development of new-quality-productivity in the Yellow River Basin. From the perspective of the evaluation indicators of new-quality-productivity, forest coverage rate, R&D personnel full-time equivalent, the number of authorized domestic invention patents, the added value of tertiary industry, traffic network density, the revenue proportion of software and information technology service industry, industrial structure, and environmental protection efforts are the main factors restricting the development of new-quality-productivity in the nine provinces (regions) of the Yellow River Basin. At the end of the paper, some suggestions are put forward, such as attaching importance to personnel training, strengthening environmental protection, encouraging scientific and technological innovation and accelerating industrial upgrading.

Due to its complex terrain and special climate, Qinghai Province is prone to sudden and destructive mountain floods. In order to provide a basis for the monitoring and prevention of mountain floods in the region, taking the Longyangxia-Jishixia section of the upper reaches of the Yellow River in Qinghai Province, where mountain flood disasters were relatively severe, as the study area, 10 influencing factors of mountain flood disasters were initially selected. Based on the data of 115 historical flood disaster points in the study area from 1958 to 2000, four factors with strong correlations were eliminated through Pearson correlation test. The remaining six influencing factors were classified. GIS spatial analysis technology was used to obtain the classified data of the six influencing factors. The entropy index method was adopted to calculate the weights of each factor and identify the main disaster-causing factors. The research results show that elevation, annual precipitation, terrain roughness, NDVI, distance from the river course, and aspect are the disaster-causing factors of mountain floods in the study area (with the weights of 0.571 6, 0.144 8, 0.107 9, 0.094 8, 0.071 9 and 0.009 0 respectively), among which, elevation, annual precipitation and terrain roughness are the main disaster-causing factors. According to the classification of the main disaster-causing factors, 91.30% of the historical mountain flood disasters in the study area occur in the areas with an elevation lower than 3 091 m, 99.14% occur in the areas with an annual precipitation greater than 317 mm, and 98.26% occur in the areas with a terrain roughness less than 1.10.

As a supporting project of the Xiaolangdi Key Water Control Works, the Xixiayuan Counter-Regulation Reservoir suffers significant loss of effective storage capacity, directly affecting the comprehensive benefits of the reservoir. Accurate calculation of floodplain and main channel evolution is crucial for the operation and management of the reservoir. On the basis of a one-dimensional mathematical model of reservoir water and sediment, this study proposed a calculation method for floodplain and main channel evolution in the Xixiayuan Reservoir, drawing on the calculation method for river floodplain and main channel evolution. The calculation method was applied to the floodplain and main channel evolution of Xixiayuan Reservoir in 2018 and 2020. The reliable results in the reservoir area confirmed the feasibility of the method.

Facing the national strategic requirements of improving the ecological environment quality and high-quality development in the Yellow River Basin, in order to promote the conservation and intensive utilization of water resources, this paper constructed 15 evaluation indexes including water resources system, socio-economic system and ecological environment system. The entropy weight method was used to evaluate the water resources conservation and intensive utilization level of 50 cities in the upper and middle reaches of the Yellow River Basin from 2018 to 2021, and identified the main factors affecting the water resources conservation and intensive utilization level of cities in the study area by using obstacle model. The results show that the overall level of conservation and intensive utilization of water resources in the study area is on the rise, from 0.505 in 2018 to 0.553 in 2021. The utilization rate of reclaimed water, the proportion of agricultural water use and the sewage treatment rate are the main obstacle factors affecting the improvement of the level of conservation and intensive utilization of water resources in the study area. Based on this analysis, the countermeasures for the conservation and intensive utilization of water resources were put forward from four aspects of water saving, social and economic development, ecological environment protection and unconventional water resources utilization.

In order to investigate the effect and mechanism of digital economic development on carbon emission in the Yellow River Basin, based on the panel data of 76 prefecture-level cities in the Yellow River Basin from 2011 to 2020, we measured the level of digital economic development, the total amount of carbon emission and the intensity of carbon emission in the Yellow River Basin, and built an individual and time two-way fixed-effects model to conduct empirical analysis, and conducted robustness tests on the results of the lagging effect of digital economic development, changing the sample capacity, and substitution variables. The empirical results are tested for robustness such as lagged effect of digital economic development, changing sample capacity, and substitution of variables, the mechanism of technological progress and industrial structure upgrading, and the heterogeneity of location and heterogeneity of resource endowment of carbon emission reduction effect of digital economic development. The results show that a) the digital economic development has a significant inhibitory effect on carbon emission intensity and total carbon emission in the Yellow River Basin. b) Technological progress and industrial structure upgrading are important mechanisms for digital economic development to promote carbon emission reduction in the Yellow River Basin. c) There is significant location heterogeneity and resources endowment heterogeneity in the inhibitory effect of digital economic development on carbon emission in the Yellow River Basin, and the inhibitory effect on carbon emission in the middle and upstream areas of the Yellow River is significantly better than that in the downstream areas, and the inhibitory effect on carbon emission in the middle and downstream areas is significantly worse. The inhibition effect on the total carbon emissions in the middle and upper reaches of the Yellow River is significantly better than that in the lower reaches, the inhibition effect on the carbon emission intensity in the upper reaches has not yet appeared, and the inhibition effect on the carbon emissions of non-resources cities is significantly greater than that of resources cities. Countermeasures and suggestions are put forward to coordinate the coordinated development of the digital economy in the Yellow River Basin, strengthen the promotion of green and low-carbon technological innovation, accelerate the transformation and upgrading of the industrial structure, implement differentiated digital economy development strategies, and effectively curb carbon emissions.

The Xiaolangdi Reservoir is a key project for controlling water and sediment of the Yellow River. Studying its sediment discharge law and regulation indicators is of great significance for maintaining effective storage capacity in the long term. Based on the analysis of measured data and the practice of water and sediment regulation, 34 sediment discharge processes in the Xiaolangdi Reservoir from 2010 to 2023 were selected, and the reservoir sediment discharge law and its influencing factors were analyzed, in the meantime the regulation indicators which were useful to reducing reservoir silt were proposed. The results show that, during water and sediment regulation in pre-flood season, sediment discharge is mainly caused by flushing of clear water discharged by the Sanmenxia Reservoir. The sediment discharge amount is positively linear correlated with the inflow volume and negatively linear correlated with the storage volume of the Xiaolangdi Reservoir. During water and sediment regulation in flood season, the sediment discharge ratio is negatively correlated with the degree of reservoir damming and the ratio of inflow and outflow flow, which is a power function relationship. The quantitative expressions of sediment discharge amount during water and sediment regulation in pre-flood season and sediment discharge ratio during water and sediment regulation in flood season are established, and the water level of the reservoir can be reduced and then maintained to 215 m and 223 m respectively during water and sediment regulation in pre-flood and flood season are proposed, in which the annual sediment discharge ratio can reach 125%.

In order to deeply explore the characteristics and driving factors of runoff changes in the Shiyang River basin, and provide a scientific basis for basin management planning and ecological environment building, this study utilized the runoff data from 1956 to 2019 and applied mathematical statistics to analyze the runoff characteristics, in conjunction with meteorological data to assess the impact of climate change on runoff. The findings reveal that a) a decreasing trend in runoff volumes for the Gulang River, Huangyang River, Zamu River and Jinta River, while the runoff of Dajing River and Xiyang River remains relatively stable. b) The basin exhibits periodic changes over 2 to 10 years and 10 to 30 years. c) Apart from the Dongda River and Xida River, which lack significant abrupt change years, other rivers in the basin have notable abrupt changes in runoff between 1970 and 1990. d) The precipitation variation trends in the Shiyang River Basin are not significant, while the temperature has significantly increased. e) Based on the division of change points, the runoff reduction between the baseline and the change period ranges from 13.78% to 37.43%, with human activities identified as the key factor causing runoff reduction and changes.

There is independence and integration between water supply and sediment reduction in sediment-laden river reservoirs. How to maintain effective storage capacity and meet water supply requirements for a long time is one of the issues to be solved in the efficient operation of sediment-laden river reservoirs. In this paper, Dongzhuang Reservoir of Jinghe River was taken as the research object. Through the analysis of measured data and mathematical model calculation, the measured hydrological sediment and cross-section erosion and deposition in the lower reaches of Jinghe River and Weihe River were analyzed. The reservoir sediment discharge flow index which was beneficial to reduce the sediment deposition in the lower reaches of Weihe River and maintain the effective reservoir capacity for a long time was studied, and the joint regulation mode of reservoir runoff and sediment was put forward. The outcomes show that during the main flood season for the sediment interception period from July to September, when the inflow is greater than 600 m³/s and the sediment concentration is greater than 300 kg/m³, the Dongzhuang Reservoir is open for sediment discharge. As the normal operation period, during the main flood season from July to September, when the inflow exceeds 300 m³/s, the Dongzhuang Reservoir will open for sediment discharge. The reservoir cannot supply water during the sediment discharge period. The joint regulation of the Dongzhuang Reservoir and the surrounding four storage reservoirs can reduce the deposition of the lower reaches of the Weihe River by 11 million tons per year, increase the guarantee rate of agricultural irrigation from 30% to 50%, and increase the guarantee rate of industrial water supply from 57% to 95%.

In order to provide reference for the policy research of ecological protection and highquality development in the Yellow River Basin, taking 9 provinces in the Yellow River Basin from 2006 to 2020 as the research object, the evaluation index system of ecological protection and highquality development was built respectively. It measured by entropy method and explored the coupling coordination relationship and obstacle factors between the two systems with the help of coupling coordination model and obstacle degree model. The results are show that a) the overall trend of ecological protection and highquality development in the Yellow River Basin is good, but the heterogeneity of each province is obvious. b) The coupling and coordination degree of ecological protection and highquality development in the Yellow River Basin is on the rise as a whole, but the level is still lower. In terms of time sequence, it has experienced the evolution process of near imbalancebarely coordinationbasic coordination, and the spatial distribution pattern is downstream > midstream > upstream. c) The coupled and coordinated relationship between ecological protection and highquality development in the Yellow River Basin is mainly constrained by the triple constraints of pollution control, ecological construction and innovative development, and there are differences in the main obstacle factors in each province (region).

In view of the issues existing in the current research on runoff evolution in the Aksu River basin, such as a single time-scale and insufficient consideration of the sensitivity of sequence length, a variety of methods such as Mann-Kendall trend test, Theil-Sen Median trend estimation, Pettitt mutation test and wavelet analysis were adopted to systematically study the runoff evolution laws of the main and tributary streams in this basin at different time scales such as inter-annual, intra-annual and flood events. The results show that the annual runoff of the Taushgan River, Aksu New River and Tailan River increase gradually, while the change of the Kumarak River is not obvious. The periodic oscillation of the four rivers is the most obvious on the 35-year, 55-year, 35-year and 55-year timescale, and the corresponding periods are 21-23 years, 32-35 years, 19-25 years and 36 years respectively. The annual distribution of runoff in the Aksu River basin is uneven, the runoff is larger in summer and autumn, and smaller in winter and spring, and the concentrated period is from June to August. The annual maximum flood peak discharge of the mainstream and tributaries fluctuate greatly, mainly concentrate in July and August. The key periods for flood control are July-September, April-August, July-August and July respectively. The tendency, mutability and periodicity analysis results of the runoff in the Aksu River watershed are all affected by the length of time series.

Identifying the variations and controlling factors of groundwater levels is very crucial to evaluate the effects of groundwater exploitation reduction (GWER), and it is an important prerequisite for accurately predicting the evolution of groundwater levels in the area of GWER. This paper selected the eastern plain of Handan as the study area, which was a pilot area of GWER in Hebei Province. Wavelet analysis, statistics and GIS methods were jointly used to analyze the spatial-temporal variations and controlling factors of shallow groundwater (SGW) and deep confined groundwater (DGW) levels during the years from 2018 to 2021. The results show that the annual head fluctuation range of SGW is from 0.9 to 7.3 m, and the annual head fluctuation of DGW varies from 2.8 to 17.6 m. The water level reaches to the bottom in July and reaches to the peak in December. The water levels in most areas show a rising trend in both SGW (0.8-4.6 m) and DGW (0.6-6.3 m). The depression cone areas for SGW and DGW are enlarged in dry seasons (SGW is 347.9 km² and DGW is 60.6 km²) and are reduced in wet seasons ((SGW is 91 km² and DGW is 516.2 km²). The water-level changes in SGW are closely related to precipitation, with a lag time of 141 to 224 days. The water diversion from the Yangtze River and the Yellow River, aiming to replace groundwater exploitation for industrial and domestic use as well as agricultural irrigation, has contributed to the reduction of groundwater pumping, and thereby boosted the recovery of water levels in this region.

In recent years, there has been an increase in extreme rainfall events, and flood risk remains the biggest threat to the Lower Yellow River. Therefore, it is of great significance to study the changes in the flood characteristics of the Lower Yellow River for flood disaster prevention and reduction. This study analyzed variations in flood peak flow and sediment concentration during different periods by using measured flow and sediment data from the Huayuankou Hydrological Station from 1974 to 2020. The dynamic time warping algorithm was employed to calculate asynchronous duration in the wandering reach of the Lower Yellow River, with the changes in hydro-sedimentary asynchronous characteristics and their influencing factors investigated. The research results show that the floods in the braided reach of the Lower Yellow River are mainly of medium size. After the operation of the Xiaolangdi Reservoir, the proportion of low sediment concentration flood events reaches to 85.9%. The average peak-shape coefficient decreases to 1.33, and the main type of flood asynchrony has been changed from the synchronous type of flood peak and sediment peak to the lagging type of sediment peak. The relationship between the lag duration of sediment peak lagged-type floods and influencing factors were analyzed, such as incoming sediment coefficient, duration and sediment type coefficient. A formula for calculating lag duration was established, with computed values generally aligning well with measured values.

In order to address climate change and water resources pressures, and to achieve sustainable regional water resources utilization under the carbon neutrality target, the InVEST model was employed to assess carbon storage and water yield in the Qinhe River Basin from 2000 to 2020. The study also used geographical detectors to explore the driving factors and explanatory power, and spatial autocorrelation analysis to examine the spatial relationship between the two. The results show that: a) Water yield in the Qinhe River Basin has shown a fluctuating increasing trend, rising from 1.020 billion m³ in 2000 to 1.167 billion m³ in 2020. This change aligns with the trend in precipitation, with carbon storage and potential evapotranspiration being the main driving factors. b) Carbon storage decreases from 167.566 7 million tons in 2000 to 167.110 5 million tons in 2020, following a trend similar to soil carbon storage, with potential evapotranspiration and water yield being the primary driving factors. c) The global Moran’s index of water yield and carbon storage is -0.2, showing no significant spatial distribution overall. Spatially, there is a pattern of high water yield-low carbon storage and low water yield-high carbon storage.

In order to study the impact of the operation of cascade reservoirs in the upper reaches of the Yellow River on the hydrological regime of the downstream section, the Longyangxia Reservoir to Liujiaxia Reservoir section was taken as the research area, the Mann-Kendall mutation test was used to examine the years of abrupt changes in the average annual flow of the inflow and outflow hydrological stations (Tangnaihai, Guide, Xunhua, and Xiaochuan hydrological stations) from 1952 to 2021, the hydrological change index method-hydrological change range method (IHA-RVA method) was used to quantitatively evaluate the hydrological change degree of the monthly average flow of the inflow and outflow hydrological stations, Pearson correlation analysis method was used to evaluate the correlation between annual runoff and annual sediment discharge at the inflow and outflow hydrological stations. The results show that the flow of hydrological stations entering and leaving the reservoir exhibits periodic changes and overall increases, while the annual average flow of the upper reaches of the Yellow River undergoes a sudden change after the operation of the cascade reservoirs. After the operation of the reservoir, the monthly average flow of hydrological stations located upstream of the reservoir shows moderate to low changes, while the monthly average flow of hydrological stations located downstream of the reservoir shows moderate to high changes. The monthly average flow change is related to the “flood storage and dry discharge” operation mode of the reservoir. The annual sediment discharge of the inflow and outflow hydrological stations shows a decreasing trend, with the Tangnaihai Hydrological Station in the upstream showing the smallest decrease in sediment discharge, and the Xiaochuan Hydrological Station in the downstream showing the largest decrease in sediment discharge. The annual runoff is significantly positively correlated with the annual sediment discharge.

Under the combined influences of global climate change, evolving underlying surface conditions, and anthropogenic activities, the hydrological-sediment regimes of the Yellow River Basin have undergone notable modifications in recent decades. These alterations have consequently driven adaptive transformations in fluvial landscapes, including waterfall systems. As a natural waterfall formed along the mainstem of the Yellow River within the Jin-Shaan Grand Canyon, Hukou Waterfall serves as a critical study target. Leveraging long-term continuous in-situ monitoring data, field investigations, and historical archives, this research systematically investigated the primary landscape characteristics of Hukou Waterfall-encompassing morphology, scale, and coloration, while elucidating its interactive relationships with reach-scale hydrological and sediment dynamics. Furthermore, an analysis of the waterfall's historical evolution from 1956 to 2023 reveals two key findings: a progressive reduction in overall scale since 1956, and a significant increase in the occurrence frequency of clear-water flow events.

The banks of the Dongzhuang Reservoir area of the Jinghe River are crisscrossed with gullies and have a deep loess cover. After the reservoir area is filled with water, the fluctuation of water level will increase the probability of deformation and instability of new reservoir banks and the revival of ancient landslides. Based on the geological conditions of Dongzhuang Reservoir area, three typical water-related landslides with high risk (Hejia, Jiaojiahe and Fengjia) were selected for the analysis of the causes of landslides and the distribution characteristics of landslides. The coupling mechanism between landslide deformation and water level fluctuation after water storage were analyzed by establishing numerical models. The results show that there are three higher-risk water-related landslides and they are typical loess-bedrock landslides within the 30 loess landslides in the reservoir area. The stability of loess landslides along the bank of the reservoir is affected by the fluctuation of reservoir water level. The gradual decline of reservoir water level and the long-term maintenance of high water level will lead to the reduction of the safety coefficient of the landslides. The faster the rate of decline of reservoir water level, the faster the safety coefficient of the landslides decreases to the minimum value. The possibility of overall large-scale sliding of loess landslides in the reservoir area is low. Conversely, the risk of instability of the leading edge slides is relatively high when the water level drops.

he formation and evolution of the Ω-shaped channel of the Yellow River depend on the boundary morphology and interactions of the tectonic belts around the Ordos block. The collision, subduction, compression, strike-slip and whirl effects of the peripheral tectonic belt on the block have made the Yinchuan Graben, Hetao Graben, Jin-Shaan Gorge and other tectonic landforms through the Yellow River. The highly developed fault zone, cataclastic rock zone and dense joint zone in graben and canyon have strictly controlled the extension and bend of the channel. In Neoid period, the extrusion of the Indian Plate in NE-trending and the Pacific Plate in NW-trending has compounded new activities of the peripheral major fault, which has controlled and constrained the Ω-shaped channel of the Yellow River.

In order to explore the influence mechanism of new quality productivity to the carbon emissions in the Yellow River Basin, and then provide references for developing new quality productivity and promoting carbon reduction and emission reduction in the Yellow River Basin, this paper took 2013-2022 as the study period and nine provinces in the Yellow River Basin as the measurement unit, and used the entropy method to measure the development level of new quality productivity according to the three indicators of labor force, labor object and labor data. Furthermore, the direct impact of new quality productivity on carbon emissions was tested empirically by using the fixed effect model of individual and time factors, and the robustness test was conducted. The mechanism of influence of new quality productivity to the carbon emissions was tested empirically with the level of industrial structure upgrading and green technology innovation as the intermediary variable, and the level of market integration and the target of economic growth as the moderating variable. The results show that a) the development of new quality productivity has a significant inhibitory effect on carbon emissions in the nine provinces of the Yellow River Basin. b) New quality productivity reduces carbon emissions by improving the level of green technology innovation and industrial structure upgrading. c) Excessive economic growth target will increase carbon emissions and weaken the carbon reduction effect of new quality productivity, while the improvement of market integration level will reduce carbon emissions and enhance the carbon reduction effect of new quality productivity. Suggestions: Further improve the institutional mechanisms for the development of new quality productivity, continue to strengthen support for enterprises' green innovation and further optimize the industrial structure, so as to enhance the carbon reduction and emission reduction effect of new quality productivity.

As a result of the heavy rainfall, flooding remains in the later stages of the rainfall and may continue to cause harm and impact. In order to accurately predict the depth and duration of urban flooding and waterlogging, the RF-LSTM model was proposed to address the difficulty of simulating floods in the later stages of the heavy rainfall. Based on the SWMM model-simulated flood data in Zhengzhou City, China, the flood depths at three representative flooded points were simulated by using the proposed model, and the flooding process caused by rainfall under different recurrence periods was predicted. The results show that compared to the single LSTM model, the simulation accuracy of the RF-LSTM model has been improved, verifying the applicability of the model in flood simulation. The growth rates of flood duration and the maximum flood depth at flooded points are the highest under the 1-2 a return period, therefore the existing drainage system should be renovated or redesigned.

In order to screen the disaster-causing factors that induce debris flows, evaluate the performance of the three machine learning algorithms of RF, GBDT and XGBoost, in predicting the susceptibility of debris flows, and provide references for geological disaster prediction and disaster prevention and mitigation in the areas prone to debris flows, taking Hainan Tibetan Autonomous Prefecture, Qinghai Province as the study area and based on historical debris flow disaster data, based on the initially selected 17 influencing factors and the Pearson correlation coefficient of debris flow disasters, the disaster-causing factors that induce debris flow were screened. The remaining disaster-causing factors were classified and 8 combinations of disaster-causing factors were set. The three machine learning algorithm of RF, GBDT, and XGBoost were used to predict the susceptibility of debris flow. The prediction effect was evaluated by indicators such as accuracy rate, precision rate, recall rate, F1 score, and ROC-AUC. The results show that a) distance from the river channel, elevation, soil erodibility, topographic moisture index, annual rainfall, normalized vegetation index, coefficient of variation of elevation, lithology, topographic roughness, profile curvature, curvature, slope, coefficient of variation of elevation, and aspect are the disaster-causing factors that induce debris flows in the study area. Among them, elevation, distance from the river channel, soil erodibility, topographic moisture index, annual rainfall, and normalized vegetation index are the main disaster-causing factors. b) When the three algorithms of RF, GBDT and XGBoost are used to predict the likelihood of debris flow, the prediction effect based on the disaster-causing factor combination C7 (this combination does not consider slope direction) is the best, and the prediction effects based on the disaster-causing factor combinations C5 (this combination does not consider curvature, coefficient of variation of elevation and slope direction) and C8 (this combination considers all disaster-causing factors) are also good. c) When predicting the susceptibility of debris flows based on the disaster-causing factor combination C7, the ranking of the advantages and disadvantages of the three algorithms is XGBoost, GBDT and RF.

In order to solve the coordination problem between agricultural green development and ecological protection in the Yellow River Basin and identify the reasons behind the contradiction between agricultural production and ecological environment protection, the paper took the nine provinces (regions) in the Yellow River Basin as the research object to build an evaluation index system for agricultural green development and ecological protection was constructed. The entropy method was used to measure the agricultural green development index and ecological protection index of each province (region) from 2006 to 2020. The fusion coordination model was used to calculate the coupling coordination between agricultural green development and ecological protection, and the obstacle degree model and grey correlation degree model were used to diagnose and analyze the obstacles and driving factors of coupling coordination development. The results show that during the research period, the coupling coordination degree between agricultural green development and ecological protection in the Yellow River Basin shows an overall upward trend, with a spatial pattern of “upstream>downstream>midstream”. There is still a significant gap between each province (region) and high-quality coordinated development. The coordinated development of agricultural green development and ecological protection is mainly hindered by the dimensions of output efficiency and resources endowment. The internal driving factors that affect the degree of coupling and coordination between agricultural green development and ecological protection in the Yellow River Basin, in descending order of correlation, are the proportion of nature reserves area, the multiple cropping index of arable land, forest coverage, grain yield per unit area, per capita arable land area and fertilizer application intensity. Therefore, it is necessary to strengthen the overall coordination of agricultural industry development planning in the upper, middle, and lower reaches of the Yellow River Basin, accelerate the flow of factors such as technology, capital, and labor between regions, and formulate differentiated agricultural development and ecological civilization construction strategies.

In order to investigate the influence of land use change to the basin flood process, the Fenhe River Basin was chosen as the study area. The SWAT model and the extreme land use scenario analysis method were employed to analyze the effects of land use type changes on the flood process in different periods and scenarios. The results show that a) the mean value of Nash-Sutcliffe Efficiency(E_NS) is greater than 0.70 and the mean value of determination coefficient (R²) is greater than 0.65 during the calibrated and validated period, indicating that the SWAT model has good applicability in the Fenhe River Basin. b) Between 2000 and 2020, there is a reduction in the area of cultivated land, grassland, water bodies and unused land, while the area of forested land and built-up land is increased. c) Under the land use in 2000, 2010 and 2020, each peak flow and the total flood volume show a slight upward trend. d) Under the arable land scenario, there is an increasing trend in each peak flow and its total flood volume; while under both the woodland and grassland scenarios, there is a decreasing trend. In terms of magnitude of impact, land use type change has a smaller impact on larger flood processes and a larger impact on small and medium flood processes. Therefore, it is necessary to increase the area of forest and grass and vegetation coverage, promote water-appropriate planting, and avoid high-water-consuming vegetation in areas with high incidence of flood disasters and serious soil erosion, so as to improve the ability of flood control, flood resistance, disaster prevention and mitigation in Fenhe River Basin, and promote ecological restoration and high-quality development in Fenhe River Basin.

混凝土坝；变形监测；变形预测；LSTM；TCN

Using remote sensing technology to dynamically monitor the utilization type of the Yellow River embankment-line is helpful to understand the construction process of ecological corridor along the Yellow River. This paper took the middle reaches of the Yellow River as the research object, extracted embankment-line utilization information at intervals of 5 years based on Landsat-5 TM and Landsat-8 OLI images from 1993 to 2023, analyzed the spatial-temporal variation characteristics of embankment-line utilization after the implementation of the national strategy of ecological protection and high-quality development in the Yellow River Basin and preliminarily discussed the effectiveness of ecological protection of the Yellow River corridor. The results show that from 1993 to 2023, the proportion of living embankment-line in the middle reaches of the Yellow River is increased from 2.12% to 16.96%, and the proportion of ecological embankment-line shows a fluctuating upward trend, reaching 39.68% in 2023. The embankment-line utilization of three sections in the middle reaches of the Yellow River is quite different, among which, the ecological embankment-line is mainly used in the Jin-Shaan Valley section, the agricultural embankment-line is mainly used in the Fen-Wei Plain section, and the Sanmenxia-Taohuayu section has changed from an agricultural embankment-line to an ecological embankment-line. From 2018 to 2023, the increase of ecological embankment-line and living embankment-line and the decrease of agricultural embankment-line are the most significant, and the ecological embankment-line of each section shows positive changes.

Influenced by external conditions such as climate and river channels, ice-run disasters in the Inner Mongolia section of the Yellow River are characterized by strong suddenness and destructiveness, which brings great pressure to ice prevention in the Yellow River. Especially, the Shisifenzi bend in the Toudaoguai section of the Yellow River in Inner Mongolia is very easy to become the initial ice-run position every year due to the influence of multiple factors such as the shrinkage of the river channel, the increase of the ice volume from the upper reaches and the morphology of the river channel. In this paper, in view of the frequent occurrence of flooding disaster and the difficulty of risk prevention and control in the Shisifenzi section of the Yellow River in Inner Mongolia, based on the measured topography and water depth data of the river channel and using the hydrodynamic module and particle tracking module of MIEK21, a coupled numerical model of ice-run was constructed, and a simulation analysis was carried out on the Shisifenzi River section of the Yellow River to study the trajectory of ice-run under the conditions of different incoming ice quantities and the densification of the ice. The result reveals that the ice movement law in Shisifenzi section of the Yellow River.

The reservoir-dam group on the main stream of the upper reaches of the Yellow River serves as a critical flood control barrier. While delivering comprehensive benefits in flood mitigation, water supply, power generation and ecological conservation, it faces complex and dynamic natural disaster risks. By analyzing the characteristics of natural disaster risks in this region, the paper discussed the main natural disaster risks faced by reservoir and dam groups and the challenges of risk management and response. The results indicate that natural disasters in the upper reaches of the Yellow River dam-reservoir system exhibit compound and systemic features, where extreme events such as mega-earthquakes, giant landslides, and super-standard floods may trigger disaster chains. Disaster prevention and mitigation are confronted with challenges such as insufficient identification of multi-source dynamic risks, the need to improve the joint regulation and emergency response mechanism, and the lagging adaptability to climate change.

In order to provide a reference for building the ecological compensation mechanism in the Yellow River Basin from the perspective of taxation, especially the horizontal ecological compensation tax mechanism, this paper analyzed the limitations of the existing ecological compensation schemes such as vertical ecological compensation from higher governments to lower governments, intra-provincial (regional) horizontal ecological compensation and inter-provincial (regional) horizontal ecological compensation in the Yellow River Basin, and put forward the idea of “fee to tax” for horizontal ecological compensation in the Yellow River Basin. From the perspective of tax regulation, the advantages of tax compensation in external governance, system design, vertical and horizontal complementarity and rebuilding of central-local relationship of ecological compensation were discussed. In terms of mechanism design, the corresponding analysis was made between water resources tax, environmental protection tax and ecological compensation tax and the key areas of ecological compensation, such as water conservation, cross-province (region) boundary water pollution, soil and water conservation and ecological compensation integrated management. Integrating the design of tax system into the ecological compensation mechanism could give full play to the regulating role of tax revenue, so that the horizontal ecological compensation mechanism can play a key role in the ecological function and economic and social development of the upper, middle and lower reaches of the Yellow River Basin.

In order to calculate the maximum population scale and economic scale that the urban water resources in Qingdao City can support, and to formulate the urban development model for urbanization and sustainable utilization of water resources, the entropy weight method was used to measure the water resources carrying capacity and urbanization level of Qingdao City from 2015 to 2022. A system dynamics model was built from both water resources and social economy aspects, and the water supply and demand situations of four development models (natural development, rapid development, water conservation priority, and comprehensive development) from 2023 to 2030 were simulated. The results show that the water resources carrying capacity of the urban area of Qingdao City shows a fluctuating upward trend from 2015 to 2022, and the urbanization level is steadily increased. The comprehensive development is the optimal mode of the urbanization development in Qingdao City, which can ensure that there is still a surplus water resources after meeting the needs of residents' life and economic development.

In order to enrich the study of carbon ecological security and high-quality development in resources-based cities of the Yellow River Basin and provide the basis for promoting the construction of ecological civilization and high-quality development, the evaluation index system was built. The level of coupling coordination and its spatial-temporal differences and spatial agglomeration characteristics from 2012 to 2021 were analyzed by the coupling coordination model and the spatial autocorrelation model. The results show that the level of coupling coordination for carbon ecological security and high-quality development of resources-based cities in the Yellow River Basin from 2012 to 2021 has been increasing year by year, with the growth rate in the middle reaches being faster than that in the upstream and downstream. The spatial agglomeration effect of coupling coordination is significant for carbon ecological security and high-quality development in resources-based cities, which is characterized by a “fluctuating upward trend”. Coupling coordination between carbon ecological security and high-quality development in most resources-based cities are distributed in “high-high and low-low” agglomeration areas, and is characterized as a “belt like” distribution. It is suggested that resources-based cities in the Yellow River Basin give full play to their comparative advantages, formulate differentiated plans, strengthen division of labor and cooperation, enhance regional correlation, exert a radiating effect and promote coordinated development, so as to achieve the coordinated advancement of carbon ecological security and high-quality development throughout the basin.

山西省万家寨引黄工程泵站压力隧洞(竖井)建成后,砼裂缝较为密集,部分隧洞充水后发生明显漏水.经反复处理后情况虽有所改善,但仍未完全奏效.经分析,裂缝与水泥用量较大、不设伸缩缝、隧洞超挖以及施工质量控制不严等因素有关,建议采取合理分缝、降低水泥用量、改进泵送砼施工工艺以及加强缺陷处理等措施.在内水压力较高的情况下,钢衬仍不失为最安全可靠的设计方案.