Based on the runoff data of Qinghai Lake Basin from 1956 to 2016, this paper uses concentration ratio，accumulative anomaly, linear trend regression testing method, M-K mutation test，Morlet wavelet analysis of regular pattern of runoff in the Qinghai Lake in the past 60 years, results show that: The runoff is not evenly distributed within years; the runoff has undergone a process from dry to moderate and then to abundant, which reflects the periodicity, the stage and the continuity of water cycle changes. There is an obvious upward trend of the quantity of runoff after 2003.The runoff suddenly changed from 2002 to 2005. According to wavelet analysis, the main period of annual runoff lasts 24 years, which means that the runoff will continue to be excessive in the next few years. The results can provide a scientific basis for water resources protection and ecological restoration of Qinghai Lake.

The Yalong River Basin is rich in water resources. The construction of water conservancy projects, reservoir operation, flood control and drought relief all need the support of runoff forecasting. In this paper, the distributed hydrological model based on DEM grid is established, the improved SCS model is selected for runoff generation calculation, and the conceptual source sink model is selected for confluence calculation; the T-G fusion method based on spatial distribution is proposed to revise TRMM data; and hydrological model is carried out driven by TRMM RT and V7 revised data. The results show that, the error of TRMM data is reduced and the error distribution is more stable after being revised; the TRMM revised data drives the distributed hydrological model, the runoff simulation peak shape is similar, the two data simulation accuracy grades are class C and class B, and the secondary flood error can be controlled within the qualified rate, which meets the prediction requirements. Considering the applicability evaluation results of TRMM and the performance of driving distributed hydrological model in runoff forecast, TRMM data can also be used as a supplement to the measured precipitation data in Yalong River Basin. At the same time, the research method in this paper serves as a reference for the runoff forecast in Yalong River Basin, and TRMM data can be used as a substitute for the measured data in the area without data.

Based on daily precipitation data of 15 meteorological stations in flood seasons in Henan Province from 1960 to 2018, the methods of linear regression, trend analysis, the precipitation concentration index(Q) and GIS are employed to analyze the spatial-temporal distribution characteristics of precipitation and its concentration degree in flood seasons in Henan Province. The results indicate that, from 1960 to 2018, the precipitation and Q index in flood seasons of Henan show an upward trend, with a tendency rate of 0.45 mm/10 a and 0.002 /10 a, respectively. The precipitation days decreased at a rate of -0.107 d/10 a, and the precipitation in flood season tended to be concentrated in Henan during 1960-2018. The Q index of flood season in Henan showed a decreasing trend from northeast to southwest, while the precipitation increased from southeast to northwest, and precipitation days in flood seasons decreased from southwest to northeast. It showed that the area with more precipitation in flood seasons had more precipitation days and more scattered precipitation. The effective precipitation days in flood seasons decreased at a rate of -0.257 d/10 a, while the heavy precipitation and extreme precipitation days presented increasing trends, with a tendency rate of 0.027 and 0.012 d/10 a, respectively, showing that the proportion of heavy precipitation and extreme precipitation days was increasing, the precipitation was more concentrated, and flood disaster was more likely to occur. From the perspective of spatial distribution, the number of effective precipitation days in eastern and northern Henan was less than that in other areas, but the number of strong precipitation days and extreme precipitation days were more, showing the precipitation was more concentrated.

Bangladesh is located at the delta formed by Ganges River, Brahmaputra River and Meghna River, with a special topography and geomorphology characteristics. The three rivers are all located at the strong rainfall area, large storm-flood confluence to Bangladesh and then to the sea. Especially for Ganges River and Brahmaputra River, whose confluence of large amount of flood outside of Bangladesh, usually made Bangladesh suffered flood disaster. On the basis of summarizing the situation of the topography, geomorphology, river systems, flood disaster, an analysis is made of the flood causation, flood types, flood source, flood season, flood peak style, characters of flood peak and flood amount, occurrence time of annual maximum flood and its encounter traits of Ganges River and Brahmaputra River. The causation of Bangladesh prone to flood disaster is revealed when the flood characteristics are explored. It also supplies some technical reference for the flood research and flood disaster control in Bangladesh.

In order to solve the problem of lack of river water quantity data in some areas, a method of river water quantity estimation based on Landsat remote sensing image is proposed. The proposed method constructs the surface area - water volume curve using ENVI to extract the water area of remote sensing image, combined with the known water volume data to obtain the estimation equation. The Qinhuai River Basin is selected as the research area. Based on the Landsat7 and Landsat8 remote sensing images from 1999 to 2016, the surface area of Qinhuai River-annual/monthly runoff relationship curves are constructed respectively. The results show that the surface area and runoff has a strong correlation (R2>0.75). Through the analysis of the estimation effect of different linear models and the selection of the optimal model and the accuracy verification, it is found that the exponential model under different time scales is most suitable for the estimation of the runoff of Qinhuai River. The results show that this method can effectively solve the problem of insufficient hydrological data and has good accuracy.

To expand the runoff and groundwater level prediction model of growth application areas, improve the prediction accuracy of the model proposed artificial ecosystem Optimization (AEO) algorithm - growth prediction model portfolio.Six standard test functions and Schumacher and usher model parameter optimization examples are selected to verify the AEO algorithm, and the simulation results are compared with those of whale optimization algorithm (WOA), gray wolf optimization algorithm (GWO), teaching optimization algorithm (tlbo) and particle swarm optimization (PSO).Based on the Schumacher and Usher single growth functions, the Schumacher-Usher combination growth model is constructed. For the practical problems of selecting the combination model parameters and weight coefficients, the AEO algorithm is used to optimize the combination model parameters and weight coefficients at the same time, and the AEO-Schumacher-Usher combination growth is proposed. Prediction model, and build AEO-Schumacher, AEO-Usher, AEO-SVM model for comparison, using literature runoff and groundwater level prediction as an example for example verification.The results show that the optimization accuracy of the AEO algorithm is better than the WOA, GWO, TLBO, and PSO algorithms, and it has better optimization accuracy, global search capability, and robust performance. The absolute value of the average relative error predicted by the AEO-Schumacher-Usher model for the two examples is 2.32% and 0.15%, respectively. Prediction accuracy and generalization ability. The AEO algorithm can effectively optimize the parameters and weight coefficients of the combined growth model. The AEO-combined growth model is feasible and effective for the prediction of runoff and groundwater level. The model and method can provide reference for related prediction research.

Systematic domestic water demand prediction is of great importance for the sustainable development of society and economy. The basic concept of social hydrology is introduced in this study, which integrates a series of comprehensive factors, such as nature, population, economy, environmental awareness and so on. System dynamic modeling is proposed in this paper, which couples with social-hydrological multi-factors for realizing the domestic water demand prediction. The key socio-economic factors that affect the domestic water demands most are identified. The prediction equations of population, urbanization rate and income level are deduced. The expressions of water-saving consciousness are proposed for the first time. The development trend of key factors affecting the domestic water demand is investigated. Furthermore, the differential and difference equations for domestic water demand prediction are established to realize the future domestic water demand forecasts considering the nature and social driving forces. The upper and middle Pearl River Basin is selected as a case study. Results show that the proposed model can be used for the simulation of the population, urbanization rate, income level, water saving awareness and so on. The predicted domestic water demands are consistent with the historical results. Thus, the proposed model can be used for domestic water demand prediction. This paper provides a new way for domestic water demand forecasting.

Evapotranspiration (E) is one of the most important components for detection and attribution the changes in water cycle, especially in regions significantly affected by human activities. In this study, water cycle changes in the Yangtze River is investigated based on 7 public widely used evapotranspiration products including 4 diagnostic model datasets (i.e. EMTE, EGLEAMv3a, EPML, EMTE-WB) and 3 re-analysis products (i.e. EMERRAa, EMRRRAs, EERA). A water balanced evapotranspiration data (EWB) is derived as a reference to assess the spatial and temporal characteristics of all the 7 E products. Results show that mean annual evapotranspiration for the entire basin of 7 products ranges from 645 to 955 mm/a, which are all higher than EWB. The coefficient of variation (Cv) of annual evapotranspiration ranges from 0.01 to 0.05. All 7 products show an increasing trend in annual E with an average rate of 1.25±0.46 mm/a2 (about 2.23±0.82 billion m3/a), especially in the middle-lower reaches. This study provides a reference about the water cycle change in the Yangtze River Basin based on current available evapotranspiration products.

Partial probability weight moment method and higher-order probability weight moment method are both improved parameter estimation methods based on probability weight moment method. In this paper, the statistical characteristics of partial probability weight moment method and higher-order probability weight moment method are compared and their application effects in flood frequency analysis and calculation are studied. Monte Carlo test is adopted to simulate, analyze and compare the statistical characteristics of the two methods. Taking the annual maximum flow series of Shenmu hydrological station as an example, this paper estimates the parameters of GEV distribution and design values of different return periods, and fits the data series. The results show that the unbiasedness and effectiveness of HPWM method are significantly better than that of PPWM method. PPWM method and HPWM method are both suitable for flood frequency analysis and have similar fitting effect, and HPWM method is relatively simple.

In order to further study the water flow characteristics of the flow field between cylinders, a particle image velocimeter (PIV) is used to perform a model test on the flow field of the axial velocity of the two-cylinder section, and the axial velocity distributions in different sections are compared and analyzed. The results show that as the distance from the rear cylinder increases, the trend of axial velocity distribution between cylinders is rotationally symmetric-the axial velocity distribution is uniform-trending to rotational symmetry. In the flow field between the measuring ring cylinders with different diameters, the axial velocity distribution of the downstream part of the water gradually deviates from the center line of the pipe axis as a whole under the action of the upstream diversion strip. After the water flows along the guide strip of the rear cylinder and the structure of the support body to the test range, the axial velocity of the support body close to the rear cylinder becomes negative under the influence of the rotationally symmetric support body.

As the Chinese economy is facing transformation and upgrading, serious environmental problems are receiving constant attention. It is very valuable to study water environmental governance and rural green industry upgrading. By using the provincial panel data of China from 2012 to 2015, the mechanism of rural green industry upgrading under water environmental governance is explored. A random-effect model is established to analyze the role of water environmental governance in the upgrading of rural green industries. The results show that pollution prevention can promote the upgrading of rural green industries. However, regional heterogeneity also exists, and the impact of water environmental governance in economically developed regions is more pronounced than in economically underdeveloped regions. Finally, relevant policy recommendations are proposed based on the research results.

In order to explore the non-point source pollutant load and spatial distribution of pollutant sources in the Shaanxi section of the Danjiang River Basin, the output coefficient method and parity pollution load method are used to estimate and evaluate the pollution load of the five counties in the Shaanxi section of the Danjiang River Basin in 2017. The spatial distribution and contribution of different pollution loads in each county are analyzed by GIS. According to the main pollution sources, targeted control measures have been put forward. The results show that the pollution load amounts are 6 209.22 t of TN, 36.956 t of TP, 2 187.88 t of NH4-N, and 22 681.14 t of COD in 2017. The largest pollution sources for TN and COD are agricultural land, and TP and NH4-N are livestock and poultry farming. There is a strong consistency in the spatial distribution of each pollutant, but there is still a difference in the equivalent pollution load of each county. The research aims to provide a decision-making reference for the prevention and control of non-point source pollution in Shaanxi section of Danjiang River Basin.

In order to respond quickly to urban storms and floods, an urban storm flood model is constructed based on cellular automata to quickly simulate the flood evolution process in the event of a heavy rain. It is necessary to set the rules of runoff generation and confluence that meet the characteristics of the city's complex underlying surface, and fully consider various runoff generation factors and solutions under special circumstances. Case study of the main urban area of Jinan City is carried out. The results show that the cellular automata can obtain reliable results in addition to the advantages of fast calculation in large area flood simulation. The calculated submerged water depth and measured data are approximate. Compared with traditional models based on mathematical physics equations, the cellular automata model has low data requirements and intuitive expression, and can be well applied to urban flood evolution simulation. Key words:

In order to reveal the impact of land-use change on the ecological risk of the lower reaches of Tarim River after the comprehensive management of Tarim River in 20 years, by using the Landsat remote sensing images of 2001, 2010 and 2019, a model of landscape ecological risk assessment under the land-use change is constructed, and the research on the land-use change, landscape ecological risk assessment and its spatio-temporal differentiation in the lower reaches of Tarim River is carried out. The results show that: from 2001 to 2019, the area of unused land in the lower reaches of Tarim River decreased, and the area of water wetland, forest land and grassland increased significantly. The spatial distribution of landscape ecological risk shows a significant positive correlation, mainly for the high-high and low-low clustering model. The lower reaches of Tarim River are dominated by low and lower ecological risk areas, accounting for more than 72.61% of the basin area. The high ecological risk areas are mainly distributed in water wetland, the low ecological risk areas are mostly distributed in forest land and grassland, the low ecological risk areas are mainly distributed in unused land, and the cultivated land distribution area changes from high to medium ecological risk. The overall ecological risk increased slightly and then decreased gradually. The area of higher and high ecological risk decreased significantly by 42.4%. The ecosystem in the lower reaches of Tarim River is gradually recovering.

In order to grasp timely the variation of water ecological environment in Poyang Lake，the surface water samples were collected from eleven sampling sites in Poyang Lake in Apr., Aug. and Dec. of 2017. The physicochemical parameters of water quality in each period were analyzed. The water quality and eutrophication level were evaluated by single factor index and comprehensive nutrient status index. The results indicate that physicochemical parameters were significantly different in temporal and spatial in Poyang Lake, and the overall water quality was Ⅴ standard. The water quality was the worst in the dry season, and relatively better in the wet season. In different periods, the content of pH, DO, CODMn, NH+4-N of water at various points met or exceeded Ⅲ class water quality standard, but TN and TP were mostly Ⅳ or Ⅴ standards. The present nutrition status in the flat water period and wet season of Poyang Lake was mesotrophic and the transition to mild eutrophication. In the three periods, the water areas from Hukou to Pingfeng and from Duchang to Tangyin were generally mildly eutrophic, while the water areas from Xingzi to Duchang was mesotrophic.

In order to study the impact of different flooding stresses on the process of rice growth enzyme activity in leaves and yield components, and put forward relative drainage index, simulation of flooding stress status was conducted through rice pot culture experiment, and the response characteristics of physiological status and yield of semilate rice under different flooding stresses was stuided at elongation stage. The results showed that the tillering growth will be inhibited ,the plant height increased significantly with the water logging duration and flooding depth. Malonaldehyde (MDA) in the leaf blade increased with the water logging duration and flooding depth. Peroxidase (POD) in the leaf blade increased with the water logging duration, Superoxide dismutase (SOD) in the leaf blade a change as follows: When water logging duration was 1、3 and 5 days they increased with flooding depth, while when the water logging duration is 7 days, they decreased as the flooding depth increased. Yield reduction was due to the decrease in effective ears and grain quality. When the flooding depth was 40cm, and the water logging duration was 1、3、5 and 7 days, the yield reduced by 12.64%、15.37%、23.42% and 28.75%, respectively. Taking a reduction of 20% in seed yield (80% of relative yield) as a standard in designing drainage in paddy field, and the regression model with rice yield as dependent variable, flooding depth (H), waterlogging duration (D) and SFW as independent variables was constructed, According to the models，when the flooding depth was 20cm, 30cm, and 40cm, the flooding water must be drained to 10cm 8.5, 6.5 and 3.5 days, respectively.

It proposes novel ways to analyze the velocity distribution along normal direction of boundary in concave channels. Based on the theory of flow division, the points which can represent the average velocity of the mathematical model are verified, and measurement methods under different hydraulic conditions in concave boundary are further explored. The results show that the velocity is distributed along the normal direction in the bottom section of the arc. The accuracy of velocity measurement normal in the bottom section of the arc is higher than that of the velocity perpendicular. There are special positions on any velocity measurement normal that can represent the average velocity of the velocity normal, and the number of velocity normal under the same accuracy requirement is less than that of the velocity perpendicular, so it is more convenient to operate.

With the help of CNKI and WOS databases, this study quantitatively analyzes the amount of published papers, cited papers and high-frequency key words in the field of flood and drought prevention at home and abroad in the past five years. The results show that in recent five years, the volume of literature on flood and drought prevention has been increasing, and the development of the discipline is good. Both at home and abroad, the most direction of the published papers is the model method. From the distribution of the volume of publications and the volume of citations per article in all fields, the domestic output advantage lags behind the influence advantage, while the international output and influence generally show a positive correlation. From the perspective of high frequency key words, the domestic frontier hot spot is flood forecast and urban waterlogging prevention. The application of remote sensing technology in flood and

Pumping Station is one of the important infrastructures guaranteeing the agricultural irrigation. Pump is the core equipment of the pump station system, whether the design and selection of pumps is reasonable or indirectly affects the life of pumps, investment cost and stable, safe and low-consumption operation of the pump stations after construction. In this paper, for pump station with multiple outlets along the pipeline, two representative typical engineering cases of status and problems are introduced in detail. It is known through the analysis of pump selection design, when there are multiple outlets along the pipeline, the pump frequency conversion operation scheme can be preferred to solve the water supply problem for different outlets. When the head difference for two outlets along the pipeline is large, but the difference of flow is small, pump frequency conversion scheme cannot meet water supply requirements, two pumps in series can be used to solve the problem of water supply.

Based on Bentley hammer V8i water hammer analysis software, the water hammer analysis and protection settings of three-stage super high lift and long-distance pumping stations in the second phase of water supply project of Qin'an County for urban and rural water supply of Gansu Province are carried out. The lifts of pumping stations are 276, 199 and 246 m respectively. The water delivery pipelines of three pumping stations are affected by the terrain, and the negative pressure and the pressure rise of water hammer is very obvious. Through simulation analysis and calculation, the three pump stations adopt hydraulic control check eccentric hemispherical valve, air valve, pressure fluctuation pre check valve and other protective equipment, effectively eliminating the negative pressure of pipeline and reducing the pressure rise of water hammer when the pump stops in accidents.

In order to find out the influence of the interaction of different factors on the soil conductivity value, the change rule of the soil conductivity value under the interaction of several factors such as soil salt content, volume moisture content and density is studied through the indoor simulation test, and the main influencing factors of the soil conductivity value are analyzed. The results show that there is a significant positive linear correlation between soil volume moisture content and soil conductivity under different soil densities in saline soil. In saline soil, the soil volume moisture content and salt content have an effect on soil conductivity, but the change of soil volume moisture content has no significant effect on soil conductivity, and the change of soil salt content has a significant effect on soil conductivity.

Based on the ANSYS CFX commercial code, the N-S equation and the RNG k-ε turbulence model are applied to simulate the flow characteristics in the forebay of the pumping station. The calculation results show that the flow pattern of the original scheme is not uniformly distributed under the three working conditions of the old station operating independent, the new station operating independent, and the “old station + new station” operating simultaneously. In order to solve the above problems, three kinds of guiding scheme for the bottom sill, the column and the “bottom sill + column” are proposed. Under different working conditions, the flow pattern in the forebay is significantly improved by utilizing different kinds of guiding schemes. For scheme 2, the large-scale recirculation zone is effectively eliminated, the water flow can inflow the outlet pipe symmetrically and uniformly, and the axial velocity distribution uniformity of the inlet section of the sump is better than that of scheme 1 and scheme 3.The verification of simulated results is obtained through quantitative and qualitative comparison, the test and simulated results are in a good agreement. The numerical calculation method is reliable and the calculation result is credible.

The facilities of water measurement in irrigation areas are the basis of comprehensive reform of agricultural water price. According to the characteristics of different types of irrigation projects and management levels in Zhejiang Province, combined with the current situation of the comprehensive reform of agricultural water price, and through the investigation of the water measuring facilities of irrigation areas in Zhejiang Province, this paper analyzes the current situation of construction and management of the water measuring facilities, and summarizes the models of water measurement and their applicable conditions under different regional types, which is helpful to strengthen the management of agricultural water utilization and promote the comprehensive reform of agricultural water price, and provides a reference and guidance for improving irrigation water measuring facilities in the same type of areas of South China.

In order to reveal the relationships between the main meteorological factors and corn yield at different stages of its growth period, based on the daily meteorological data of 23 stations in Liaoning Province from 1960 to 2017 and the sowing area and total yield data of corn from 1998 to 2017, this paper uses the Mann-Kendall test and the 5-year linear harmonic sliding average method to analyze the inter-annual variation trend of each meteorological factor and corn yield, on this basis to investigate the effects of meteorological factors on corn yields. The results show that: ① In recent 58 years, the average temperature in Liaoning Province increases at a significant rate of 0.21 ℃/10 a(p<0.05). The sunshine duration decreases at an obvious rate of 23.42 h/10 a(p<0.05). The decrease rate of precipitation is 3.37 mm/10 a. ② The per unit yield of corn in Liaoning Province does not change obviously in the past 20 years, which reduces at a rate of 59.12 kg/10 a. The meteorological yield is relatively discrete, but the overall trend is upwards. ③ In terms of the influence of meteorological factors on the corn yield, the average temperature and the sunshine duration during the growth period of the corn are both negatively correlated with its meteorological yield. Compared with the negative effects, the precipitation has more positive effects on the corn yield. The flare period is a key period for meteorological factors to influence the meteorological yield of corn. The results aim to provide a scientific basis for rationally utilizing the law of the climate change to step up the products of grain and achieve the local food security.

In order to explore the effect of biochar and modified biochar on the infiltration, evaporation capacity, soil water content, pH and salt content of saline soil. We carried out a soil column experiment to study the infiltration and evaporation process of coastal saline alkali soil under the conditions of two kinds of biochar (conventional straw biochar as A, phosphoric acid modified biochar as B) and three added amounts (2%, 4%, 8%) as well as one blank group as control (CK, A1, A2, A3, B1, B2, B3). The dynamics of wetting front migration, cumulative infiltration amount, evaporation amount, soil water and salt content, pH was measured and discussed. ①The application of biochar and modified biochar could effectively promote the infiltration of soil water, and the promoting effect was improved with the increase of biochar application. ②The addition of modified biochar could increase the soil water content one day after the end of soil infiltration, and have better improve in the soil pH. The B3 treatment significantly increased the salt content at 0~15 cm soil layer, while the A1 treatment significantly reduced the salt content at 15~30 cm soil layer. ③The effect of on soil evaporation under each treatment is small, soil evaporation was inhibited only under A3 treatment. It can effectively reduce the pH of soil, promote the infiltration of soil water, and improve the saline soil by adding 4% modified biochar to it.

China is a country with severe water shortage. Agricultural water accounts for more than half of the total water consumption. Therefore, measuring the effective utilization coefficient of farmland irrigation water and assessing agricultural water efficiency have become important topics. This paper takes the Pihe Main Canal in Pishihang Irrigation District of Anhui Province in 2019 as an example, and uses the multi-year data of the Irrigation Experimental General Station in Pishihang Irrigation District of Anhui Province to estimate the irrigation water utilization coefficient and compare it with the first-place method. The results show that the measured value of the effective utilization factor of irrigation water for the irrigation channel of the Pihe Canal in 2019 is 0.52, and the estimated value is 0.53. Compared with measured methods, the RMSE of net irrigation from is estimation method 17.982 5, 0.014 1, and MSR is 3.60%, 1.39%, with better accuracy and stability indicating that the estimation method can be used as an effective method for measuring the effective utilization coefficient of irrigation water, and can also be used to verify the accuracy of data for large-scale irrigation districts.

Due to its unique advantages of solar energy resources, Qinghai Province has huge potential of developing photovoltaic water extraction technology. In order to solve the problems of grassland irrigation and drinking water for humans and animals in the remote and non-electric pastoral areas of Qinghai, four types of suitable photovoltaic water-lifting irrigation models with their technical indicators for grasslands in alpine drought areas in Qinghai were summarized and refined, based on the existing research projects and results. At the same time, the promotion and application of photovoltaic water lifting irrigation technology and its social, economic and ecological benefits, were analyzed. The results show that: The suitable photovoltaic water-lifting irrigation models mainly include rainwater collection irrigation mode, surface water irrigation mode, shallow well water-lifting irrigation mode, and medium and deep well irrigation mode. Compared with the diesel power generation system, the photovoltaic water lifting system can save 337.5 tons of diesel, 1 032.75 tons of carbon dioxide emissions, and 491.77 tons of standard coal; Compared with traditional irrigation, it can save 55.56% of water and increase production by 20% to 45%; it has an important role in improving the living standards of local people, promoting the ecological environment and economic development, and have a good prospect of promotion and application.

Being restrained by the complicated water level changes in rivers and canals and the shortage of concrete functional form, it is impossible to solve the built transient phreatic flow motion model of the semi-infinite region under the control of such type of boundary conditions. In this paper, the Laplace transformation considering no boundary condition forms is adopted to solve, and the differential theorem and convolution theorem of the Laplace transformation are applied to give out the theoretical solution of the model. Meanwhile, the Lagrange interpolation is conducted in the water level changing process of rivers and canals to give out the model solutions for being applied in solving practical problems and comparison with numerical solution. The results show that, this is a simple and feasible method, based on which, the given model solutions are all conventional functions. Besides, combining with the interpolation functions, the calculation checking, which is conducted by using relative parameter-seeking methods and practical cases, show that the results are basically coincided. This provides relative references for the solving of transient phreatic flow model solution near rivers and canals.

In order to measure water and take water more accurately, allocate and utilize water resources reasonably, and save water more effectively, a multifunctional water level monitoring equipment with high precision, high stability, simple structure, and functions of water level measurement, flow conversion, data display and all network communication is designed. Starting from the measurement principle, structure design and circuit design, the design and development process of magnetostrictive integrated water level gauge is introduced in detail. In addition, a calibration platform is designed, which is approved by the Inspecting and Testing Centre for Hydrological and geotechnical instrument's quality of the Ministry of Water Resources, and the performance of the instrument is verified on the platform. The instrument has also passed the commission inspection conducted by the Inspecting and Testing Centre for Hydrological and geotechnical instrument's quality of the Ministry of Water Resources，and all indicators meet the requirements of the first level accuracy of the electronic draft national standard. At present, 40 instruments have been installed in Da'an Irrigation Area and have been running for a irrigation season, they are in good conditions and praised by customers.

In order to study the permeability characteristics of fractured rock mass with filling medium, the seepage model of single fracture with filling medium is established and the analytical solution of seepage volume is given by combining Navier-Stokes equation and Brinkman-extended Darcy equation. Without filling medium, the seepage volume formula could be simplified to the cubic law. Based on the seepage principle of fracture network, the mathematical model of seepage network of fractured rock mass with medium is constructed, and the influence of the properties of filling medium on the permeability of fractured rock mass is discussed through an example. The results show that under the condition of semi-filling and the same fracture width, compared with the cubic law, the seepage volume of the fractured rock mass considering the filling medium decreases by about 36.36%, indicating that the influence of filling medium on fracture permeability must not be ignored. The smaller the permeability coefficient K and the higher the filling ratio (β) is, the lower the seepage volume is. In the middle of the seepage domain, the gradient of water considering the filling medium is larger, which may lead to local erosion and damage and affect the strength of the rock mass.

Based on the brief introduction of the principle, composition, drawing method and simulation application method of cascade energy storage operation chart, an initial solution construction method of the output coefficients of operation curves and the optimization method of the output coefficients based on the progressive optimization algorithm are proposed. The proposed methods can quickly and accurately find out the optimal output coefficients of operation curves for the energy storage operation chart, and solve effectively the technical problems existing in the traditional method of determining the output coefficients of operation curves, such as the large influence of human factors, low accuracy and poor efficiency. Taking the downstream 5 reservoirs cascade system of Yalong River as an example, the optimal output coefficients of operation curves and the corresponding optimal energy storage operation chart are obtained. Although the simulation results of the energy storage operation chart are smaller than the deterministic optimization results of multi-dimensional dynamic programming, the calculation time is much shorter than that of multi-dimensional dynamic programming, and the water level process is more regular and practical, which is of great significance to guide the actual operation of cascade reservoirs.

Earthwork allocation scheme is one of the core issues of large-scale hydropower construction projects, which is of great significance to the construction progress, quality and cost of the project. A reasonable earthwork allocation scheme is of vital importance to the success of the whole project. In view of the difficulty of earth rock allocation of face rockfill dam of upper reservoir of Wuyue Pumped Storage Power Station in Henan Province, based on an analysis of solutions to similar problems, this paper adopts the method of system analysis, and uses genetic algorithm to solve the problem. In the aspect of mathematical model, taking the lowest total deployment cost as the goal, the constraints in various practical construction are considered deeply and carefully to enhance the accuracy of the model. In the aspect of program, based on Microsoft Visual Studio C# language, a software with simple operation, friendly interface and strong applicability is developed. Through the software, the optimal allocation scheme of earthwork is determined, and the rationality and practicability of the allocation system are verified in combination with actual projects.

Hydropower projects have a large investment and a wide range of social impacts, and it is particularly important to carry out regular safety checks on dams to ensure dam safety. In the past, the safety inspection of the underwater part of dams relied mainly on the way of manual diving, which faced the problems of low efficiency, high risk and high cost. In recent years, the rapid development of robotics technology has made it possible to replace manual underwater safety checks with robots in smart hydropower plants. Under this background, this paper analyzes the present situation of the development of Remotely Operated Vehicles (ROV), studies the application and problems of the current mainstream ROV in hydropower projects, and puts forward the key technical problems to be solved, and provides a scientific basis for the development of ROV equipment for hydropower projects.

With the application of BIM, the digital delivery based on BIM, which is powerfully promoting the transfer and application of BIM in different stages of the project life cycle as a new data delivery way. Targeted at the life cycle management of hydropower project, this paper deeply studies the form, process, elements and characteristics of digital delivery based on BIM. Based on that, this paper expounds the digital delivery implementation process and application in hydropower project life cycle management, which has a strong reference value to the application of digital delivery in hydropower project life cycle management based on BIM.

With the vigorous development of global hydropower, the environmental effects brought by hydropower plants construction have been widely concerned. This paper briefly introduces the assessment of greenhouse gas emissions from hydropower plants, and summarizes the research progress of greenhouse gas emissions in the life cycle of hydropower plants at home and abroad in recent years. The range of unit carbon(CO2) emissions of hydropower stations is roughly from 3.7 to 44 g/kWh, and with the increase in the installed scale of hydropower plants, the GHG emission coefficient shows a trend of decrease. Compared with the traditional thermal power, the greenhouse gas emission of hydropower is far less than that of thermal power, so developing hydropower vigorously is of great significance to the reduction of carbon emissions.

Concrete faced rockfill dam (CFRD) has been widely practiced in dam construction around the world, due to the advantages of adequate safety, distinct economic advantages, good foundation adaptability and fast construction speed for this dam type. In order to make greater use of local materials or excavated materials, more and more CFRDs have been constructed with soft rock, especially in areas where hard rock is scarce. Because of the special mechanical characteristics, the stress and deformation behaviors of dams filled by soft rocks are significantly different from those constructed by hard rock. Based on the project of Stung Tatay Hydropower Station in Cambodia, this paper estimates the deformation behavior and safety of soft rock filled CFRD. The main dam of the project is a CFRD with a maximum height of 115m. It is filled with sandstone and argillaceous siltstone excavated from the stock yard. Through deformation monitoring data and three-dimensional finite element simulation, the deformation characteristics of this CFRD constructed by soft rock are analyzed, and the dam safety status is evaluated. The analysis shows that the deformation behavior of the main dam of Stung Tatay Hydropower Station is basically stable and the dam is in a good operating condition. Constructing high CFRDs with soft rock filling materials is technically feasible and safe. The analysis results of dam deformation behavior can be used as a reference for similar projects.

Aiming at the problems of complicated BIM data formats, high computer performance requirements, and low data interaction efficiency of current hydraulic engineering projects, this paper proposes general ideas for the application of BIM lightweighting for hydraulic engineering based on IFC standards and WebGL technology. As an example, the long-distance diversion and water supply project has achieved the extension of the IFC standard for water conservancy projects. Then, with the help of the XBIM toolkit, the analysis and lightweighting of IFC files has been achieved. The development of Web-3D visualization applications has been completed based on WebGL technology. Research shows that IFC and WebGL-based lightweight BIM applications for hydraulic engineering have the advantages of open data standards, lightweight data, and cross-platform applications, and can meet the needs of BIM data sharing and interaction for hydraulic engineering with multiple data sources, platforms, and scenarios. It is helpful to promote the application value of BIM model in hydraulic engineering.

Weihai City is an area with severe water resources shortage, and the contradiction between water supply and water demand is increasing with the development of social economy. In order to alleviate this contradiction, an underground reservoir is to be built in the downstream of Muzhu River for intercepting river water and increasing the utilization of surface water and groundwater. According to the hydro-geological condition of the downstream of Muzhu River, paper constructs a hydro-geological conceptual model and a groundwater flow mathematical model through Visual Modflow, analyzes the regulation and storage of underground reservoir and selects a more suitable mining scheme. The paper draws the following conclusions: the underground reservoir of Muzhu River has great potentials for exploitation; the water regulation by storage of wet, normal, dry and special dry years is 23.928, 20.565, 17.43 and 10.128 million m3, respectively, and after the construction, Muzhu River has a great potential for development; the extraction scheme of 36 wells (23 wells in lower reservoir area and 13 wells in upper reservoir area) with a flow rate of 0.015 m3/s for the whole year is a more suitable scheme plan.

The project quality is the lifeline of the project, and the water conservancy project quality supervision and management is an important means for the government to carry out the project quality management. In view of the current situation, effectiveness and problems in the quality supervision and management of water conservancy projects in Qinghai Province, this paper puts forward the working ideas of the quality supervision and management of water conservancy projects in Qinghai Province, including the establishment of rules and regulations, the establishment of supervision system, the construction of organization team, the investment of funds, the all-round supervision, the innovation of supervision means and the improvement of personnel quality. The specific countermeasures are put forward.

Considering the phenomenon that the fins of the Bihu Reservoir overflow dam and the outflow of the river rush against the right bank mountain and combining the actual situation of the project, the tail pier and the cantilever shape are optimized through experiments, and the optimization effect of setting tail pier behind gate pier and different deflection angles of side wall of overflow dam are compared and analyzed. The results show that by setting a reasonable tail pier behind the gate pier, the phenomenon of hydrofins at the exit of the gate chamber can be basically eliminated; the optimization scheme of the right side wall deflected counterclockwise by 5°(starting at the inverse arc segment) makes water tongue of spillway outlet return tank reasonably, and avoids the phenomenon that the water flows against the right bank mountain and meets the downstream energy dissipation requirements.

The spillway dam of Baishui Project is a middle head discharge structure, with energy dissipation by hydraulic jump. Due to the influence of the downstream topography and construction layout, the length of the dissipating pool is limited, and the traditional dissipating pool cannot achieve the ideal energy dissipation effect. In this paper, the hydraulic model test is used to compare the original design scheme with two optimization schemes of the drop sill + traditional T-type baffle, the drop sill + modified T-type baffle. The flow velocity distribution in the stilling basin, outflow velocity of stilling basin, and energy dissipation efficiency are analyzed. The results show that in the mid-high-head, high-flow underflow stilling basin, the combined energy dissipator of the the drop sill + modified T-type baffle effectively reduces the flow velocity of the outflow pool, improves the energy dissipation efficiency of the stilling basin, can achieve the purpose of energy dissipation and erosion control,which serves as a reliable basis for similar projects.

With the construction of a batch of major water conservancy projects for water conservation and supply, a new round of water conservancy construction climax was lifted in our country, and engineering quality is crucial for engineering construction. Under the strong supervision of the water conservancy industry, quality inspection of water conservancy project construction has become the norm. By participating in the quality supervision and inspection of major water conservancy projects on the spot, this paper makes statistics and analysis of the violations in the construction process, reveals the characteristics of violations of quality management in engineering construction, analyzes the reasons, and puts forward the corresponding countermeasures so as to provide guidance and reference for better quality supervision and inspection work, and improve the quality of water conservancy project construction in the future.

Water conveyance channels are faced with various problems, such as weak policy, disordered water intake, inefficient management and protection, and weak supervision. As an innovative management and protection system, “Channel Commander System” can effectively make use of administrative and civil forces to formulate targeted targets, tasks and measures, and serve to improve the quality and efficiency of water conveyance channel management and protection. Jiaodong Water Diversion Project is an important part of “T” type water diversion artery which the east route of south-to-north water diversion project and the guarantee of water supply in four cities of Jiaodong. The practice of “Channel Commander System” in Jiaodong Water Diversion Project proves that the management and protection of the full coverage grid has obvious effects and advantages, which can enhance the combined force of management and protection and guarantee the orderly and stable operation of water diversion channel.

By field investigation and monitoring analysis, this paper calculates the nitrogen and phosphorus pollution load of different sources, such as the tributary water, channel water and the inflow of scattered water, in order to find out the source of pollution, and puts forward corresponding pollution control countermeasures, so as to provide technical support for the management of drinking water source and the safety guarantee of drinking water in this city. The results show that 90% and 81% of the sources of NH3-N and TP pollution load in S reservoir are from local sources, of which R5 is the largest contributor, accounting for 40% and 21% respectively; and 67% of TN pollution load is from external sources. On the one hand, the city needs to build a new sewage pipe network in the basin, promote rainwater and sewage diversion, to improve sewage collection and treatment capacity. On the other hand, it needs to coordinate and promote the protection of water sources for water diversion, so as to reduce the water supply risk of the reservoir and ensure the safety of drinking water in the city.