Mountain streams feature steep slopes, torrents and shallow flow, wide grain size distribution, various developed river bed structures and sharply variations in the streamwise direction. Such flow complexities make resistance relations and bed load transport equations in mountain streams unclear. The paper summarizes advances in flow resistance and bed load transport in mountain streams. Typical flow resistance relations and hiding function in bed load transport equations are evaluated. Researches demonstrate that there is major progress in experimental and theoretical research on flow resistance and bed load transport in mountain streams. More efforts should be made on the impact of boundary non-uniformity on flow resistance and a widespread applied flow resistance and bed load transport model.

his research proposes a method of obtaining underwater terrain data of rivers based on Google Earth remote sensing images and using Kriging interpolation to generate terrain data for the simulation of hydrodynamic water quality of rivers in areas without measured topographical data. A two-dimensional hydrodynamic water quality model is used to analyze the effect of sewage outlets on the water quality of the Jiujiang section of the Yangtze River. The method proposed in this paper is compared with the calculation results of the Jiujiang Hydrology Bureau's 2017 1∶1 000 measured underwater terrain: the maximum error of the water level from 0.1 m to 0.2 m, the maximum relative error of flow rate increases from 10% to 20%, and the maximum relative error of water quality simulation increases from 17% to nearly 30%. The image data method has a large error and is not suitable for detailed environmental quality analysis. However, it can still be promoted as a technical method in the rapid analysis of the lack of measured terrain data and the need to understand the evolution trend of water quality.

Due to algal growth and other factors, the roughness of the open channel increases as time and channel capacity decrease. The existing physical, chemical and biological algal treatment methods all have their own limitations when applied to irrigation management. An original strategy to limit the algal biomass is to carry out regular flushes. A flush is performed by increasing the hydraulic shear conditions. Consequently, to the shear stress increase, a part of the fixed algae is detached. Since algae cannot be regarded as fixed, static boundary, a hydrodynamic model calls for a hydraulic flush study. The model includes two parts: one is algal growth model, which considers environment factors including water velocity, temperature, nutrition, and light; the other one is algal detach model. Then, the model is used to simulate a typical southern irrigation channel in China. Results reveal that the algal biomass changes with environment variables, and the peak occurs in summer. The simulation results are in agreement with the algal growth law and may provide firm basis for hydraulic flush research.

In recent years, flood disasters are one of the most frequent and most severe meteorological disasters in the world. Many domestic scholars began to study flood disasters,but there is currently little research on flood disaster risk in Dongting Lake District.In this paper, a comprehensive evaluation method is used to establish a model to evaluate the flood disaster risk of Lanni Lake water system in Dongting Lake area and propose countermeasures. The results show that under different internal water levels of Xinquansi Sluice, different rainstorm intensities have different impacts on the flood disasters of the Lanni Lake water system. At the same time, raising the waterlogging surface rate and lowering the water level of the inner lake can basically eliminate the high-risk range in general years, which is more significant in reducing the low-risk areas and increasing the non-risk areas,and reduce most high-risk areas for years with a high average risk.

By taking the water pollution of Baiyangdian basin as the research object, this paper summarizes and analyzes the current situation of water quality, risk sources and risk factors. The water environment risk assessment system framework of Baiyangdian Basin using AHP has been preliminarily constructed. Finally, based on the existing research on water environment pollution in Baiyangdian Basin, the following points should be further considered: ①Strengthen the comprehensive risk assessment of water environment in Baiyangdian Basin, and use the mathematical model to comprehensively evaluate the level of water environment risk in Baiyangdian basin. ②Strengthen the study of risk early warning technology. By using the emerging internet technology to build a risk early warning simulation model, accurately prediction of the risk of water environment would be done, and the corresponding emergency response measures would be proposed. ③Strengthen the study and control of rural pollution, carry out the governance work around the three aspects of “agriculture-rural-farmers”, and accelerate the publicity and implementation of relevant laws and regulations

Based on the problem of ecological environment degradation of Ningxia lakes, this paper focuses on the key lakes in Ningxia by using the method of multi index system evaluation to establish the index system of Lake wetland ecosystem health evaluation in Ningxia, adopt comprehensive lake assessment method to carry out ecological health assessment on key lakes. The evaluation results show that Shahu, Xinghai Lake, Yuehai, and Tengger Lake are sub-healthy, while Mingcui Lake and Baohu Lake are healthy. At the same time, based on the results of the health evaluation of each lake and wetland ecosystem, the main problems are analyzed, and management recommendations for each lake are put forward to provide a basis for lake managers.

In order to reveal the migration process of riverbed pollutants in the step-pool structure, and the relationship between the intensity of the hyporheic exchange and the single-wide flow and the height ratio, the appropriate step-pool pollution control engineering parameters are explored. Underwater flow simulation of steep-pool structures, the results show that the surface water enters the river bed upstream of the step ridge, driving out pollutants to the downstream river bed for discharge, and the clean area extends faster from the step ridge to the upstream. When it extends to the downstream asymptote, the migration speed of the pollutants slows down significantly. Under the conditions of riverbed gradient and flow, the intensity of the hyporheic exchange caused by the step-pool structure is about 37 times that of a flat riverbed. The intensity of the hyporheic exchange has a power function relationship with the single-wide flow and the height ratio. When the step-pool structure is artificially introduced, the step height is 0.4 m and the spacing is 30 m, the riverbed pollutant treatment works better.

Based on the needs of the reconstruction of the tubular pump station of the Xicheng Canal Reconstruction Project, a three-dimensional steady numerical simulation is carried out for the prototype of the two-way shaft tubular pump device. By taking the shaft flow channel of pump station as the research object, five different types of shaft flow channel optimization schemes are analyzed and compared, and the characteristics of the internal flow field of the shaft flow channel during forward and reverse operation are analyzed. The results show that: by moving the shaft section forward, changing the sharp angle of the water front of the shaft to a circular arc, and using the area of each section as a control parameter to improve the area of the section with poor flow distribution can help the water flow to diffuse smoothly and improve hydraulic performance. After optimization, in the forward running state, the efficiency is 72.40% under the design flow conditions (H=3.81 m, Q=30 m3/s). And when H=2.61 m and Q=33 m3/s, the efficiency reaches a maximum of 74.53%. In the reverse running state, when H=3.9 m and Q=30 m3/s, the efficiency reaches a maximum of 60.91%, which is 1.04% higher than the original design.

The ecological environment of the Yangtze River and the Han River is related to the sustainable development of China's economy and society, which has always been the concern of the whole society. Total phosphorus has become the primary pollution indicator of the Yangtze River. According to the current situation of total phosphorus pollution in the Yangtze River Basin and the Han River Basin, the temporal and spatial distribution characteristics of total phosphorus concentration are compared and analyzed. The causes of total phosphorus pollution in the Yangtze River and the Han River are analyzed from the aspects of the natural geological factors, phosphorous chemical enterprise distribution, municipal domestic sewage and rural non-point source pollution. This paper can provide a scientific reference for the implementation of projects such as Water Supply Project from the Yangtze River to the Han River.

In the context of urbanization, the intake and drainage of human production and life have a huge impact on the pattern of rivers and lakes. On the basis of the connected pattern of natural water system, a comprehensive evaluation index system can be used to describe the influence of water transfer project on natural-artificial binary water system connectivity under different time nodes based on the network diagram of water resource allocation in the binary water cycle, combined with the evaluation index of production and living water level and the connected form the index of natural water system. By taking Langfang City as an example, the results show that the evaluation grade of the final index is consistent with the current situation survey and future planning. It shows that the comprehensive evaluation index system established in this paper is reliable and effective.

The study aims to characterize the relation of various water quality indexes and assess Shahu Lake water quality. Water Quality Identification Index(WQII), Canadian Council of Ministers of the Environment Water Quality Index（CCMEWQI）, Universal Water Quality Index(UWQI) used for assessing Shahu Lake water quality status in April, July and October from 2010 to 2017 are discussed. The results show that the Water Quality Identification Index of Shahu Lake ranges from 3.1 to 4.7, CCMEWQI fluctuates from 27.44 to 72.07, and the general water quality index fluctuates from 31.53 to 51.74. Water quality state is generally in marginal or poor grade, and the comprehensive water quality is in a deteriorating trend, and it is urgent to improve water quality. CCMEWQI and UWQI are significantly correlated with the Water Quality Identification Index. The optimal model of regression analysis between CCMEWQI and WQII are obtained under the composite and growth model(R2=0.614), and the optimal model of UWQI and WQII are obtained under the quadratic model(R2=0.970).

Precipitation, as one of the most important basic indication for hydrologic prognosis and water resources distribution, requires interpolation in measurement of precipitation. This paper, on the basis of multiple regression, forms two or more regression equations between two rainfall stations, and it will solve coefficients to the regression equations by least square method. The author studies Qinshan Reservoir rainfall station in Muyang Stream watershed of Fujian Province, by referring to reservoirs adjacent to it and provides resolves of regression equations for multiple rainfall stations. In compare of significance test between the stations, the author selects the the repression equation with the lease mean square error and applies it to interpolation of precipitation. The test result of this article offers reference to engineering practices.

In order to evaluate the groundwater resources of Aksu River Basin reasonably, the spatial variability and structural analysis of the permeability coefficient of Aksu River Basin are carried out by using the method of traditional statistics and geostatistics through field test and collection of previous research results. The results show that the variation of permeability coefficient in Aksu River Basin is more than that of confined water; the permeability coefficient of phreatic aquifer is greatly influenced by the randomness factors such as external conditions, and the confined water is greatly influenced by the structural factors such as aquifer location and formation lithology, and the best fitting model of variation function is Gauss and index model respectively; the variation degree of permeability coefficient in north-south direction is greater than that in east-west direction, and the main variation is along the Aksu River. By using Kriging interpolation, the overall performance of permeability coefficient is that it decreases gradually from north to south, the river nearby is larger than far away from the river, and the parameter division and value range of phreatic water and confined water are given. This conclusion provides a reasonable and reliable parameter selection basis for groundwater resource evaluation and numerical simulation in Aksu Area, and can be used as a reference for the study of permeability coefficient in other areas.

Water in Karst area is broken and the characteristics of vegetation and water body overlapping put forward a new type of mixed water index of the regional water resources management and evaluation plays an important role. The Puzhehei's Landsat8 OLI is based on the data of image data, building a new hybrid NEWI water index. Results show that the new water body index NEWI extracting effect is better than that of NDWI and MNDWI, especially vegetation breakage lakes contain pits and water area, NEWI calculated 25.3% degree of differentiation of water body and shadow, is greater than the NDWI (17.9%) and MNDWI (15.6%). Water's overall recognition accuracy is 88.83%, the Kappa coefficient 0.76 is greater than the NDWI (87.10%, Kappa coefficient 0.74) and MNDWI (81.93%, Kappa coefficient 0.64). NEWI water was used by the remote sensing image enhancement method, it can not only effectively extract the open water of the water body information, the edge is clear and reliable. For broken waters, NEWI water extract the highest precision, and compared with the classification of extraction process, based on the theory of the complex mathematical operation is relatively simple, easy to promote, can well improve Karst fractured zone, the accuracy of extraction and water drainage system for real-time monitoring.

The set pair analysis (SPA) is used to diagnose and identify the evolution characteristics and vulnerability of water resources carrying capacity of Guiyang City from 2005 to 2017. The results show that all level evaluation of water resources carrying capacity is higher than 2.0. After the construction and implementation of the water-saving society, and the water resources carrying capacity has shown an improved trend. Both inadequate water supply and high quotas of agricultural irrigation are responsible for the weakening of water resources carrying capacity. A series of effective ways, including the better construction of a water-saving society, improving the efficiency of water resources utilization and strengthening protection and utilization of groundwater strategic reserve resources are to better the water resources carrying capacity of Guiyang City.

The Yarlung Zangbo River Basin is not only a treasure of ecological resources, but also a sensitive area for global climate change. Based on the MODIS data from 2000 to 2015 and meteorological data of 30 ground stations, the spatial-temporal variation characteristics of the NDVI (the normalized difference vegetation index) in the Yarlung Zangbo River Basin are analyzed. The partial climatic analysis and principal component analysis are adopted to identify the dominant climatic factors that affect the NDVI change in each subzone. On this basis, the NDVI prediction models based on artificial neural networks are proposed and applied to Yarlung Zangbo River Basin. The results show: ①The NDVI in the Yarlung Zangbo River Basin is gradually increasing from the upstream to the downstream. ②The results of principal component analysis (PCA) and partial correlation analysis (PAR) show that rainfall and temperature in the first three months are the main factors affecting vegetation. ③The ANN-PCA, ANN-PAR and ANN models are proposed and applied in the Yarlung Zangpo River Basin. The average Nash coefficients are 0.75, 0.71 and 0.63 in calibration period respectively, and 0.73, 0.69 and 0.62 in the verification period respectively. The results show that climatic factor identification can improve the model accuracy significantly. The proposed models achieve satisfied accuracy and can be applied to predict the spatial and temporal trend of NDVI in the Yarlung Zangbo River Basin.

The characteristic water level is an important basis for flood control and early warning decision-making. In recent years, large-scale and long-lasting water level over-alarms have frequently occurred at the Sanhejian Water Level Station of the Huaihe River. The existing characteristic water level has gradually been unable to meet the needs of current flood control work. This paper uses upstream and downstream water surface line analysis, hydraulics method, water level process line comparison analysis, and highest water level annual frequency analysis to obtain the corresponding characteristic water levels, comprehensively considering factors such as the superelevation of the embankment, the principle of determining the characteristic water level, and the linkage of flood fighting and emergency rescue. A more reasonable and feasible characteristic water level is put forward. Finally, the impact analysis of the flooding situation on both banks of Sanhejian and the upstream polder area is carried out. The results show that the characteristic water level adjustment has little effect on the dikes along the banks of Sanhejian and the upstream polder; the original warning water level and guaranteed water level of the Sanhejian Water Level Station is too low and should be appropriately raised.

In order to obtain the optimal interpolation methods and simulate the spatial distribution of annual average precipitation in Hunan Province, this paper selects ordinary Kriging (OK), inverse distance weighting (IDW), Trend surface analysis (Trend), Spline function method (Spline) to interpolate based on data from 87 meteorological stations in Hunan Province from 1960 to 2015 under the support of ArcGIS 10.2 platform, and compares the interpolation precision of each interpolation method using cross validation method. Results indicate that: ① the spatial interpolation of precipitation in Hunan Province has uncertainties affected by many factors. ② IDW4 has the lowest interpolation error and higher accuracy, followed by Spline based on TENSION model, OK based on the trigonometric function model has slightly lower accuracy, and Trend of Order 2 has the worst interpolation accuracy. Those four methods can reflect the characteristics of the spatial distribution of annual average rainfall in Hunan Province to some extent. ③ There are certain differences in local areas among different methods, for example, OK's interpolation surface is rough, IDW and Spline have relatively smooth surfaces, and Trend's interpolation results are monotonous.

The monthly actual and potential evapotranspiration (ET) data products, including satellite-retrieved MODIS MOD16 data (actual ET MOD_ETa and potential ET MOD_ETp) and simulated by GLDAS (actual ET GLDAS_ETa and potential ET PM_ETp), are used to investigate the temporal and spatial variations of ET in the Yunnan and Guizhou (YG) region. Besides, multiple aridity indicator are computed based on observed precipitation (P) and ET data to investigate the climate aridity of YG, the relationship between evapotranspiration, precipitation and regional aridity evolution are also discussed. Results show that: ①The highest annual average ETa occurs in southern Yunnan followed by eastern Guizhou, and northern Yunnan has the least ETa. As for the trend of ETa, it inclines significantly in southwestern Yunnan and it declines significantly in northern Yunnan. ②The spatial distribution of annual average MOD_ETp and PM_ETp indicate that the spatial variation of ETp is not very much, while both data sets indicate that ETp has a remarkable rise in central and northern Yunnan. ③The trend analysis of multiple aridity indicators shows that climate aridity in Guizhou province is stable, while there is a considerable drying trend in central Yunnan because of the joint effects of significant decline of precipitation and ETa and the remarkable increase in ETp.

Flood season division is one of the important aspects of flood resource utilization for reservoirs. Fisher's optimal dissection method is widely used in flood season division, while the influence of index weight on Fisher's optimal segmentation results is not clear. This paper compares the differences between the results of variation coefficient method, entropy weight method and principal component analysis method, and their effects on Fisher's optimal segmentation results based on the case study of Qiyi Reservoir in the Xinjiang River Basin. The results show that the three calculation methods of index weight are all applicable to the division of flood season by Fisher optimal dissection method, results of variation coefficient method and entropy weight method are more suitable for the analysis and calculation of index weight; there are some differences in the results of index weight determined by the three methods, but it has little influence on Fisher's optimal segmentation results in flood seasons. By calculating and analyzing the rationality of index weight in Fisher optimal segmentation, which can distinguish the difference of the index and provide reference for the optimal operation management of the reservoir.

In order to study the characteristics of agricultural non-point source pollution in Qingshui River Basin, the SWAT model is used to simulate and analyze the pollution characteristics. It can be seen from the monitoring and evaluation analysis of river water quality in the early stage, the agricultural non-point source is an important pollution source in the basin, and rainfall and runoff will have a greater impact on water quality. Based on the ArcGIS platform, SWAT non-point source pollution model of Qingshuihe river basin is constructed, and the model is calibrated and verified with the measured runoff data. The results show that SWAT model has good applicability in the basin. The TN and TP pollution loads in the basin are calculated and analyzed based on the simulation results of the model. The time distribution characteristics of non-point source pollution show that the annual output load in 2011, 2013, 2015 and 2016 was TN > TP, and obvious seasonality. Summer and winter are the peak and low periods of non-point source pollution respectively, and the cumulative load of each sub basin also shows the characteristics that the flood season is greater than non-flood season. The spatial distribution characteristics show that the key source areas with high intensity of pollution load loss are sub-basins 2, 3, 5, 6, 7, 10, 12 and 14, which are mainly distributed on both sides of Donggou and Xigou water systems, and the main land use types are cultivated land and grassland. The output load of non-point

The World Heritage Irrigation Structure has the dual attributes of irrigation engineering and cultural heritage. Based on 19 projects selected in the World Heritage Irrigation Structures in China, this paper summarizes the characteristics and values of the World Heritage Irrigation Structures, analyzes the current situation and existing problems of protection and utilization, and discusses the protection strategies from the perspective of sustainable development. The research results show that China's Heritage Irrigation Structures are characterized by rich resources, diverse types, a long history, outstanding benefits and wide distribution. All related regions have made positive contributions to the development, protection and utilization of Heritage Irrigation Structure resources. The basic principle of emphasizing both irrigation engineering and cultural heritage can be included in the protection and utilization process. Some measures can also be used, e.g. a unified management mechanism, overall planning and multiple protection, research on theoretical basis and key technologies, broadening the channels of display and publicity, and enhancing the awareness of comprehensive protection.

Four-lake watershed is the area where waterlogging disaster happens frequently and heavily. In order to quantitatively analyze the influence factors and risk distribution characteristics of waterlogging disasters, the waterlogging disaster indicator system of Luoshan drainage area is established from three aspects: the disaster-causing factor, the pregnancy disaster environment and the disaster prevention ability. Then the risk assessment model of waterlogging disaster is established. The spatial and temporal distribution characteristics of waterlogging disaster risk are analyzed. The results show that underlay surface accounts for the largest weight among all the impact factors. The second is the disaster-causing factor. The weight of comprehensive index of rainfall intensity in flood seasons is the largest among the disaster-causing factor, whose weight reache 0.159 5. When the comprehensive index of rainfall intensity in flood season is 2.889, the risk degree of waterlogging disaster in drainage area (0.957) is the critical value of severe risk. When the rainfall intensity in flood season is 1.924, the risk degree of waterlogging disaster in drainage area (0.837) is calculated as the critical value of mild risk. Luoshan drainage area can only withstand 3 a flood season rainfall intensity under current conditions. The whole area is risky when 10a flood season rainfall intensity occurs.

To study the decoupling relationship between groundwater exploitation and grain production in North China Plains, and to reveal the driving factors and temporal and spatial characteristics of decoupling effect, is of great significance to objectively reflect the effect of groundwater overexploitation, assist the precise measures of groundwater overexploitation in the main grain producing areas, and then promote the rehabilitation of groundwater resources and the sustainable development of agriculture. Tapio decoupling model, LMDI decomposition model and GIS Moran index spatial analysis method are used to analyze the decoupling relationship from the provincial level and prefecture level respectively, and the driving effect and spatial difference characteristics of decoupling are discussed. The results show that: strong decoupling is the main state of grain production and groundwater exploitation in North China Plains; water supply structure effect, water use efficiency effect and scale effect are the main factors promoting the decrease in groundwater exploitation; the decoupling degree of groundwater exploitation and grain production tends to be optimized overall. During the 13th Five-year Plan, more than 80% of the cities are in the decoupling state, and the contribution rate of dynamic effect shows the characteristics of H-H aggregation and L-L aggregation, but the aggregation area is small and there is no contiguous effect. Suggestions: focus on Hebei, Henan and Shandong provinces, increase the adjustment of water supply structure, reduce further the consumption of groundwater exploitation, promote the implementation of agricultural water saving, strengthen the driving effect of water use efficiency in western Henan and other regions, pay attention to the decreasing trend of grain sown area in Shandong Peninsula and other regions to ensure food security.

In order to study the influence of soil bulk density and water supply quality on the vertical infiltration of soil moisture, the soil of different bulk densities (1.35g/cm3, 1.45g/cm3) in Xiangshan area was taken as the research object. Select water supply quality as the influencing factor, and set 4 different conductivity water supply quality (0ms/cm, 2.5ms/cm, 5.0ms/cm, 7.5ms/cm) to soil infiltration time, infiltration rate, salt distribution characteristics The distribution characteristics of water content were studied, and Philip, Kostiakov and general empirical models were used to simulate the soil water infiltration process. The results show that the infiltration of brackish water can increase the infiltration performance of the two types of soil, and the effect on the soil with a bulk density of 1.35g/cm3 is more obvious. The Kostiakov infiltration equation can better fit the soil moisture of different bulk density Infiltration process, and the model has a higher fitting accuracy for the soil infiltration process with a soil bulk density of 1.45g/cm3. In the process of redistribution of soil moisture content and salinity, in the upper soil layer, the conductivity of 0ms/cm infiltration condition, the salt content of the soil layer of the two bulk density soils is less than the initial soil salt content, indicating that it is in different degrees Salt can be rinsed on the surface. Under the conditions of water supply conductivity of 2.5ms/cm, 5.0ms/cm,and7.5ms/cm, there are obvious salt accumulations in the soil column profiles of the two bulk density soils; Under the infiltration condition, in the upper layer of the soil, the soil moisture content of the two bulk densities showed a sharp decline trend, because the conductivity of the soil increased with the increase of electrical conductivity, but at the same depth, the soil bulk density The soil moisture content of 1.35g/cm3 is slightly higher than the soil moisture content of the sand density of 1.45g/cm3. This is because within a certain range, as the soil bulk density increases, the soil porosity decreases and the water content decreases. The movement process is hindered, which in turn affects the moisture content of the soil.

Long-distance water transfer projects are characterized by a large investment, a wide range of influences, diverse geological conditions, numerous risk factors, and complex engineering structures. These characteristics mean that it is necessary to carry out risk assessment research on such projects. In this paper, an index system of operational safety risk assessment for the central route of the South-to-North Water Diversion Project is established. The Pythagorean fuzzy analytic method is used to calculate the index weights of the probability and severity. The risk evaluation model combining the fine Kinney method and the fuzzy inference system is constructed. Finally, the operation safety of the water conveyance channel in the Henan section is selected to evaluate and determine the risk level. The evaluation results show that geological conditions, construction quality and operation scheduling risk are in the forefront.

Understanding the sealforce behavior is critical in determining the reliability/operability and vibration of centrifuge pumps. In order to study the effect of different labyrinth seal structure on rotordynamic, the Madyn2000 is used to compute the stiffness coefficient, damping coefficient and critic speed for several types of tooth height, tooth pitch, tooth thickness. And the sensitivity of different parameters is investigated. The results show that the sealforce of annular seal is stronger than the labyrinth sea. The influence of tooth height on critical speed is more sufficient than tooth pitch and tooth thickness. As tooth height increases in labyrinth seal, the direct stiffness coefficient (k) and cross stiffness coefficient(kq) decrease, while the direct damping coefficient(m) and direct damping coefficient(mq) change softly.

The scientific and reasonable placement of water quality stations is a crucial method to ensure water quality safety in the South to North Water Transfer Mid-route Project. The placement for water quality stations is constrained by monitoring efficiency and deployment costs. Besides, the uncertainty of detecting precision and pollutant attenuation characteristics also affects the placement. This paper based on one-dimensional water quality model to build the multi-objective optimization model for placement, the objective function is the lowest misreporting rate, the shortest time of detection and the lowest cost. The Jing-Shi section as a research object. Then the optimal placement is determined by the influence of detecting precision on objective function. Based on this, the influence of pollutant attenuation on the optimal placement is analyzed. The results can provide suggestions for the rational placement of water quality stations in the South to North Water Transfer Mid-route Project.

As a high-quality power source undertaking peak load and frequency regulation, hydropower stations play an important role in ensuring the safe and stable operation of the power grid, which expects a lot from the regulation performance of hydropower units. In order to improve the control quality of the hydro-turbine regulating system, based on the nonlinear model of hydro-turbine, a model-free adaptive control (MFAC) combined with discrete sliding mode approaching law control for hydropower unit regulation is proposed according to the dynamic linearization theory and Lipschitz condition. The parameter optimization of the controller of the hydropower unit is realized by using the beetle antennae search (BAS) combined with the error integral criterion function. The simulation results show that the MFAC sliding mode controller has advantages like small overshoot and short rise time compared with the optimal PID controller under different operating conditions. Meanwhile, the BAS algorithm has excellent parameter optimization effect, short calculation time and a good application prospect.

Concrete temperature parameters have an important meaning for concrete temperature control and crack prevention. This paper uses a differential algorithm to simulate the temperature field of concrete. Based on measured temperature data, this paper analyzes the error of the simulation calculation and establishes an inversion model based on measured data. Based on the specific characteristics of the inversion model, a GA algorithm is constructed. Through the calculation of the inverse model, the concrete temperature parameters that are more in line with the actual situation can be determined so as to provide a reference for the reasonable determination of concrete temperature parameters and subsequent temperature control calculations.

The swimming ability of fish is one of the important parameters in fishway engineering design and the key basis for successful fish migration in fishway. The induced velocity, critical velocity and burst velocity of Lateolabrax japonicus in Minjiang River Basin of Fujian Province are studied. The experiment is conducted in an open channel glass flume by using velocity gradient method. The characteristic velocity of lateolabrax japonicus in Minjiang River Basin is obtained for the first time, i.e. the mean values of relative induced velocity, relative critical velocity and relative burst velocity are 0.88, 2.29 and 2.65 BL/s（BL：Body length）, respectively. This study reveals the difference between lateolabrax japonicus in Minjiang River Basin and Yangtze River Basin. The relative critical velocity of the lateolabrax japonicus in the Minjiang River Basin is slightly higher than that in the Yangtze River Basin, and the relative burst velocity of the lateolabrax japonicus in the Minjiang River Basin is obviously higher than that in the Yangtze River Basin. The formula of induced velocity is improved based on the experimental data. It is firstly proposed that the total induced velocity be divided into the base part and the body length increasing part, and the basic induction velocity of Minjiang lateolabrax japonicus is 0.002 3 m/s..

Aiming at improving hydropower optimal operation on the basis of the existing characteristics of the source load in Guangxi, takes the five main hydropower stations in Guangxi power grid as the research object, this paper analyzes the regulation capacity, operation head, meteorological factors and runoff characteristics of Guangxi Hydropower Station, abstracts the effective joint of the difference between hydropower station characteristics in the basin and change in power load for the first combined with the characteristics of difficult hydropower prediction, fast load change, complex regulation relationship and multiple comprehensive water use, puts forward the non-compensatory and compensatory optimal operation strategy of hydropower station for different regulation types in real-time scheduling, short-term scheduling, long-term scheduling, so as to increase hydropower generation and improve water utilization.

In order to quantitatively evaluate the water consumption of the middle and upper reaches of the Lancang River and the Yuanjiang River hydropower development and determine its influencing factors, the water consumption level of the middle and upper reaches of the Lancang River for hydropower development is compared with that of the whole basin. The main stream reservoir is the research object, and the consumptive water use method is used to calculate the water footprint of the hydropower station. The results show that the average water footprint of the two hydropower stations on the mainstream of the Yuanjiang River is 3.19 m3/GJ, and the average of the four hydropower stations of the Lancang River is 0.51 m3/GJ, which are lower than the national level, showing the advantages of hydropower development in the upper and middle reaches of the Lancang River. Temperature has the greatest influence on the calculation results, followed by topographical factors.