The objective of this experiment was to study the effects of fertigation with micro－sprinkling hoses on yield of wheat and maize， water use，and water and fertilizer use efficiency，to develop a fertigation schedule with micro－sprinkling hoses for wheat and maize． Field experiments were conducted in two consecutive winter wheat － summer maize growing seasons 2013 － 2015． Under fertigation with micro － sprinkling hoses，the total nutrients provided through fertigation plus base or seed fertilizer ( controlled loss fertilizer) applications were 70% of the local fertilizer amount． The results showed that compared with local surface irrigation，the yields of wheat and maize under fertigation with micro－sprinkling hoses were increased by 7．9% and 17．1% respectively． The average water consumption of winter wheat was 439．6 mm， and the irrigation amount was the largest proportion and accounted for 36． 4%，the consumption of soil water storage and precipitation accounted for 35．6% and 23．7%，the groundwater recharge was the lowest，only 4．3%． The consumption of soil water storage in 0～ 50 cm accounted for 40% of the total soil layers． The water use efficiency for winter wheat was 1．7 kg /m3 and increased by 21% compared with surface irrigation． The irrigation water use efficiency for winter wheat and summer maize were 4．5 and 13．8 kg /m3 ，increased by 103% and 62%，respectively． The partial factor productivity for winter wheat and summer maize were significantly improved by 58% and 67% under fertigation with micro－sprinkling hoses． The nutrient mainly distributed in 0 ～ 40 cm layers and the content in 100 ～ 140 cm layers was significantly decreased by 92%． The yield，water use efficiency，irrigation water and fertilizer use efficiency were increased under fertigation with micro－sprinkling hoses with the controlled loss fertilizer as base or seed fertilizer in North China Plain．

 In order to obtain the latest soil physical properties of lime concretion black soil after the change of farming pattern in Huaibei Plain and provides an important theoretical basis for rational design of irrigation and drainage system and irrigation system,a laser particle size analyzer and a pressure membrane meter were used to determine the soil mechanical composition and soil moisture characteristic curve at six different depths. The composition and soil water characteristic curves were used to analyze the variation of soil water characteristic curve and dry bulk density in the vertical direction and the classification of layered soil texture. At the same time,the parameters of Van Genuchten model were optimized by accelerated genetic algorithm through using measured values. The results show that there are differences in the vertical distribution of physical characteristics such as soil water characteristic curve,dry bulk density and mechanical composition. The water holding capacity of soil in 0 ～ 30 cm soil layer is basically the same in the range of low suction force ( 0 ～ 631.13 cm) while the suction increases. The difference is that the soil physical properties of the 30～ 40 cm soil layer are obviously different from the upper and lower soil layers,and there is a clear boundary. Therefore,it is necessary to consider the stratification when determining the minimum soil moisture content of the crop. The result of using the accelerated genetic algorithm to optimize the Van Genuchten model is that the error is small,the precision is high,and the fitting effect is good. It is feasible and reliable to describe the characteristics of the actual soil moisture characteristic curve of lime concretion black soil with the physical meaning of the optimized model parameters.

To explore the effects of water stress on winter wheat growth,canopy thermal infrared images of the wheat with different water treatments were collected by thermal infrared sensor loaded in UAV at certain moments ( 11 ∶ 00,13 ∶ 00) a day in different growth periods and the canopy temperature information are extracted. Meanwhile,this test collected the information of wheat leaf stomatal conductance ( Gs) ,transpiration rate ( Tr) and the field soil volumetric moisture content ( SWC) . The relationship between different water stress indexes ( CWSI,IG,ICWSI) and each parameter was analyzed,and the unary linear model and multiple linear regression model were used for modeling and verification. The result shows that there exists a significant relationship between the CWSI,IG,ICWSI and Gs,Tr,SWC; SWC is the best index to predict the effect of different water stress and the R2 ( determination coefficient) is above 0.800,with the prediction of RPD( residual predictive deviation) up to 2.0 in a single model; the prediction effect of CWSI is the best in the multivariate model,the R2 ( determination coefficient) is 0.928,the prediction of RPD( residual predictive deviation) is 3.041,and the prediction result of the multiple model is superior to a single model. This study can obtain a large amount of crop information quickly and provide a new approach to explore the water stress status of winter wheat by using thermal infrared remote sensing of UAV.

The soil infiltration process was simulated and analyzed based on the test data of four field measurement points and three soil infiltration models ( kostiakov－ lewis,Philip and Horton models) . To explore the influence of uncertain factors such as model structure, infiltration time and spatial variation on the infiltration process,the residual error and root－mean－square error of the model simulation over time are taken as indicators to compare and analyze the influence degree of three uncertain factors on the infiltration law of farmland. The results show that the correlation coefficients of the three models are above 0.99,and the average relative error is between 1.60% and 11.77%. Among them,the fitting accuracy of Horton model is the highest ( average R2 = 0.998 3) ,the deviation coefficient of model parameters is small,and the stability is strong. Time uncertainty fluctuates up and down with time around a fixed value,and spatial and model structural uncertainty both show a linear increase trend with time,among which time,space and model structural uncertainty vary between 0.021 8 ～ 16.228,5.674～ 107.532 and 0.004 ～ 5.504 mm,respectively. The analysis shows that spatial uncertainty has the greatest impact on soil infiltration,followed by temporal uncertainty,and the model structure has the least impact. This study can provide an important basis for the study and analysis of soil infiltration in border irrigation.

In order to reveal the regional soil moisture variation characteristics and its utilization efficiency under city background,with the Irrigation,Drainage and Hydrology Ecological Experimental Field in Yangzijin Campus of Yangzhou University ( P1) ,and the grassland in Jiangyang Road South Campus of Yangzhou University ( P2) as the study area,based on the observed hydrological and meteorological data, the Penman Monteith formula was adopted to estimate the grass evaporation quantity in the growth period,the revised Penman－Monteith formula recommended by FAO was to use calculate the reference crop evaporation amount and evaluate the moisture effectiveness; The finite difference method was used to build a one － dimensional soil water movement model combined with the unsaturated soil water movement equation. The applicability of the model was tested by the numerical simulation of the observed soil water,and the surface ( 0～ 10 cm) soil water was simulated. The results showed that the ET0 of P1 and P2 was 1 115.0 mm during the calculation period ( from October 5,2016 to October 4,2017) ,which was slightly lower than the rainfall during this period ( 1 200.0 mm) . During the calculation period ( 2017-07-01－ 2017-09-31) ,the cumulative ET value at point P1 was 129.7 mm,accounting for 24.2% of the corresponding rainfall; the cumulative ET value at point P2 was 122. 2 mm,accounting for 22. 9% of the corresponding rainfall. During the same period,the water availability parameters,ma,were 0.39 and 0.37,respectively. The root－mean－square error ( RMSE) between the simulation results of soil moisture and the measured data were 0.012 and 0.021,respectively,and the Nash efficiency coefficient ( NSE) were 0.830 and 0.928,respectively, indicating that the error between the calculation and the measured sequence of the two points was small,and the constructed one－dimensional soil moisture movement model had a high calculation accuracy. The research results are expected to provide research basis for soil water cycle of grassland vegetation and sponge city construction based on green vegetation under the background of urbanization.

In order to explore the suitability of water － saving control irrigation technology for rice in the northeast cold region of Inner Mongolia,field experiments were carried out to study the effects of three irrigation methods,including conventional flood irrigation,shallow sunlight and shallow humidity,and shallow sunlight and moisture drying,on physiological indexes and yield components of rice. The results showed that two water－saving control irrigation technologies,“light sunlight and light humidity”and“light sunlight and light humidity and dry”,could promote rice tillering and increase the thickness of single wall of rice stalk. The number of panicles and yield of rice under the two water－saving control irrigation technologies were both higher than that under conventional irrigation,and the number of panicles per unit area was increased by 16.9 ears and 23.3 ears,respectively. The yield was 3.7% and 5.9% higher than the control. The two water－saving control irrigation technologies have certain water－saving and production－increasing benefits,which provide certain theoretical support for popularizing the water－saving control irrigation technology of rice in cold region.

In order to reveal the effect of different straw mulching modes on soil water evaporation,the soil water evaporation process under different layers of double－layer straw mulching was studied through laboratory simulation experiment. The experiment set 5 models of straw single－layer covering buried depth of 80 mm ( CK) ,upper layer buried depth of 0 mm and lower layer buried depth of 300 mm ( C1) ,upper layer buried depth of 80 mm and lower layer buried depth of 220 mm ( C2) ,upper layer buried depth of 80 mm and lower layer buried depth of 300 mm ( C3) ,upper layer buried depth of 80 mm and lower layer buried depth of 380 mm ( C4) . The results showed that: under different coverage modes,the evaporation capacity was significantly different. The experiment data showed that the evaporation process could be divided into three stages: 1～ 10,11 ～ 18,and 19 ～ 24 d. The rank order from large to small is CK,C4,C2,C1,C3,C1 for 1－10d stage,CK,C1,C4,C3,C2 for 11d～ 18d stage,and C2,C1,CK,C4,C3 for 19 ～ 24 d stage. The cumulative evaporation capacity of CK was 3.154 2 kg. Compared with CK,the inhibition rate of C1,C2,C3 and C4 was 2%,3.97%,8.6% and 2.3%,respectively. According to the comprehensive analysis,double－layer straw mulching can effectively reduce soil moisture evaporation compared with single－layer straw mulching. It can be obtained that the inhibitory effect of straw burial depth at different layers on soil cumulative evaporation is ranked from large to small as follows: C3,C2,C4,C1,CK. During the whole evaporation process,the relationship between soil moisture cumulative evaporation and time under different straw mulching conditions conforms to Y= a xb.

This project aimed at the low utilization efficiency of lycium barbarum irrigation water and fertilizer in the arid area of central ningxia,combined with the practice of drip irrigation and fertilization of lycium barbarum in arid area of Ningxia,and carried out the coupling experiment of water and fertilizer of lycium barbarum under the condition of drip irrigation. The effects of different amounts of water and fertilizer on the photosynthesis and growth characteristics of lycium barbarum under drip irrigation were studied by taking supplementary irrigation amount X1,nitrogen application amount X2,phosphorus application amount X3 and potassium application amount X4 as experimental factors.The results showed that: ① the chlorophyll in the whole growth period of lycium barbarum presented the rule of rapid growth and later stability.② the order of leaf area growth rate in the whole growth period of lycium barbarum from big to small was: treatment 3,treatment 1,treatment 6,treatment 2,treatment 5,treatment 4; ③ plant height increased first and then decreased during the whole growth period. The growth speed of plant height during the whole growth period was in the following order from big to small: treatment 3, treatment 5,treatment 2,treatment 6,treatment 1,treatment 4. ④ the order from big to small of branch growth speed in whole growth period of lycium barbarum was: treatment 3,treatment 4,treatment 1,treatment 5,treatment 6,treatment 2. ⑤ the order from big to small of the growth rate of the whole growth period of lycium barbarum was: treatment 3,treatment 2,treatment 1,treatment 5,treatment 6,treatment 4. ⑥ the order from big to small of average daily net photosynthetic rate is: T3,T5,T1,T6,T4,T2.The order from big to small of daily average transpiration rate is: T3,T6,T1,T5,T4,T2.In summary,leaf area,plant height,branches,growth rate of ground diameter and average daily net photosynthetic rate and average daily transpiration rate in treatment 3 were the maximum values in the experimental design treatment,and chlorophyll was the second.

In order to reasonably guide the application of water－saving irrigation technology for vegetables in coastal facilities and promote the further development of green agriculture,it is very important to study the water consumption law and yield of major vegetable crops under water stress. Five irrigation treatments were used to measure soil moisture content,dry weight and fresh weight of tomatoes. Water consumption was calculated and analyzed by using water balance equation and rising water flux model of the interface under root layer. The relationship between dry weight and fresh weight of tomato and irrigation water was analyzed. The results showed that with the increase of water stress,water consumption and yield of tomato decreased,water use efficiency increased,and dry matter growth rate increased in flowering and fruit－setting period and fruit－picking period.Under different water stress conditions,the response of tomato to water stress was small at seedling stage,the change range of daily water consumption was 0.2～ 1.5 mm,the flowering and fruit－setting stage and fruit picking stage were the most sensitive to the degree of water stress,and the change range of daily water consumption was 0.1～ 5.2 mm.When irrigation water was 270 mm,the yield of tomato could reach 98% of the full irrigation yield,and the water production efficiency could be improved by 9.38%,which could provide a reference for the development of accurate irrigation system.

Aiming at the problem of water－saving and production－increasing of potatoes in the middle arid region of Ningxia,the relationship between soil moisture content and growth index of potato root area under different irrigation treatments was explored by using“kesin no.1”as experimental material and using single － factor randomized block experiment design. The effects of different irrigation treatments on water consumption,yield and quality of potato during the whole growth period were analyzed. The results showed that the growth index of potato was the best when the soil moisture content of potato root area was 15.63% to 20.81%,which was beneficial to the growth of potato. On the whole,the potato water consumption law in the middle of Ningxia showed a trend of low water consumption intensity in the early stage, gradually increased in the middle stage,and then decreased in the later stage. When the irrigation quota was set as 1 260 m/hm2 ( 35 L/ plant) ,the watering period was set as seedling stage,tuber forming stage and tuber growth stage,and the watering amount accounted for 25%,25% and 50% of the irrigation quota respectively,the potato had the best growth,the highest quality,the best effect of water－saving and increasing yield,and the yield could reach 25.88 t /hm2 .This irrigation system is conducive to the promotion and use in the central region of Ningxia.

 In order to provide a quick and effective method of quantitative estimation for the water and nutrient exchange between mainstream and tributaries of Three Gorges Reservoir,the characteristics of hydrogen and oxygen isotopes and the two element linear mixed model was used in this paper to quantitatively analyze nutrient exchange in water bodies. Through the determination of the temporal and spatial distribution of hydrogen and oxygen isotopes and the content of nutrients in the water of the typical small tributaries in the Three Gorges Reservoir area,the contribution of the main stream to the tributary of the Caotang River in each operation period of the reservoir is estimated, and the contribution of the main stream water to the TP and TN of the tributary of the Caotang River is discussed. The results show that the water supply rate from the main stream is 96.4% and the source water supply is only 3.6%. In addition,the analysis of nutrient content in the tributary of the Yangtze River and the tributary of the Caotang River showed that the supply of TP was basically from the main stream,and the annual variation trend of TP and TN was basically the same as that of the adjacent Yangtze River. The source TP of the tributaries is obviously lower than that of the backwater area,and TN has a sudden increase only in summer and October,indicating that the source water quality is better. It is estimated that the annual supply of TP to the tributaries in the Yangtze River is estimated to be 25.49 t,and the recharge of TN is about 479.57 t.

According to the relationship between the groundwater system and the external environment in Shawan county,combined with the data of the average buried depth of the groundwater level in the irrigation area from 1998 to 2017,three correlation rank test methods, including Pearson,Kendall and Spearman,were adopted to analyze the environment changing trend of the irrigation area in the nearly 20 years and its influence on the groundwater dynamics. The principal component regression analysis was used to determine the main driving factors affecting the change of groundwater depth in irrigation areas. The results showed that in the past 20 years,the average annual temperature in the irrigation area presented an insignificant increase trend,while the precipitation presented an insignificant decrease trend. In the past 10 years ( 2008－2017) ,the surface water irrigation amount presented a significant decrease trend at the level of a = 0.01,and the irrigation area,water－saving irrigation area and groundwater exploitation all presented a significant increase trend. The driving factors of groundwater dynamic change are groundwater mining,surface water irrigation,water－saving irrigation,irrigation area,air temperature and precipitation,and the influence degree decreases successively. Human activities play a leading role in groundwater dynamics,among which the increase of water－saving irrigation area with groundwater as the main water source is the main reason for the decrease of groundwater level. The sustainable utilization of groundwater resources in the study area should be realized by adjusting agricultural structure,improving agricultural irrigation efficiency,and combining water － saving irrigation with surface and underground water while converting farmland to forests and filling wells.

Scientific and objective evaluation of the sustainability of PPP projects in water environment treatment is not only related to the smooth implementation of the project,but also important for the success of PPP projects and the sustainable development of water environment treatment in China. By combing the literature,this paper firstly constructs the sustainability evaluation index system of water environment treatment PPP project from the five aspects of economy,engineering,project company management,social sustainability and resource and environmental sustainability,using the relative importance index value. The index system is revised to construct the final evaluation system. Secondly,the interval intuitionistic fuzzy set is used to evaluate the sustainability of the water environment governance PPP project. The WC－OWA operator is introduced and the decision maker＇s risk preference is introduced to deblur the indicator. Finally,based on the entropy weight method to calculate the index weight,the project with the best sustainability is determined,and the feasibility of the method is verified by an example. It provides a kind of assessment for the sustainability of PPP project in water environment management. The algorithm borrowed.

Nitrogen leaching leakage is one of the main causes of agricultural non－point source pollution. Through the measuring bucket experiment,the dynamic change of ammonium nitrogen ( NH+4 －N) ,nitrate nitrogen ( NO－3 －N) and the total nitrogen ( TN) leaching in the underground drainage at the 5 growth stages,including rice tillering stage,the jointing－booting stage,heading to flowering stage,milk－ripe stage and yellow ripeness stage under different irrigation modes,including control irrigation ( CI) ,drought planting with straw mulching ( DPS) and frequent shallow irrigation ( FSI) . The results showed that the concentrations of NH+4 －N,NO－3 －N and TN in the underground drainage of each treatment increased rapidly after fertilization. The underground water displacement at tillering stage and jointing－booting stage accounted for 64.6% ～ 73.4% of the total water displacement,with high concentration of NH+4 +N,NO－3 －N and TN,and large nitrogen loss. Nitrogen forms in underground drainage of different irrigation modes at different growth stages are all dominated by NH+4 －N,accounting for 47.2% ～ 59.4% of TN,and NO－3 －N accounting for 30.3% ～ 43.4% of TN. Underground drainage is one of the main ways for NH+4 －N loss. Compared with FSI,CI and DPS reduced underground drainage by 45.8% and 69.9%,nitrogen loss load by 42.5% and 71.6%,but CI increased production by 4.6% and DPS reduced production by 3.7% due to long－term water stress. Taking all factors into consideration,the controlled irrigation mode can save water and reduce emissions while maintaining a high yield,while the dryland straw mulching mode has obvious advantages in reducing nitrogen loss.

The chemical composition and environmental isotopes in 32 groups of water samples in the Toksun river basin were determined, and the chemical components sources were analyzed by using clustering,Piper three－line maps,Gibbs diagrams and ion－proportionality coefficients method,and the isotopic characteristics of water environment in the study area were also analyzed to determine the hydrochemistry and composition of groundwater in the area. The results showed that the groundwater along the Aragou river system from the gravel diluvial plain in front of the mountain mouth to the fine soil plain to the salt marsh plain is from HCO3 type to HCO3·SO4 type,SO4·HCO3 type and SO4·CL type; the groundwater chemistry is also influenced by evaporation and concentration,leaching and cation exchange adsorption; the chemical composition of groundwater comes from the dissolution of salt minerals; the average value of groundwater δ18O is －0.889%,the average value of δD is －5.668%,the average value of shallow surface water δ18O is －0.938%,and the average value of δD is －6.005%; the precipitation in mountainous areas has a certain influence on the groundwater recharge through the secondary transformation. The water samples far away from the local atmospheric precipitation line are affected by the supply source and artificial mining.

In order to improve the positioning accuracy of precision agriculture wireless sensor,an improved particle swarm optimization ( PSO) algorithm was proposed. Firstly,the positioning process of precision agriculture wireless sensor is established. Then,the inertia weight of particle swarm optimization is nonlinearly optimized,which makes the change of the algorithm slow in the early stage and fast in the later stage. Then,the size of the particle swarm is controlled by contraction and expansion,and its discrimination is combined with the aggregation degree and diversity function of the particles. In the early stage,the contraction and expansion coefficient of the algorithm is at a large position,and in the later stage,the speed should be slowed down to strengthen the local search ability of the algorithm. Finally,the relationship between positioning error and particle fitness function is established. The experimental simulation shows that the proposed algorithm has better convergence performance,and can effectively suppress the influence of ranging error on location and improve the positioning accuracy of nodes compared with other algorithms.

Aiming at the problem of insufficient stiffness of single cantilever beam double spraying gun supporting structure of hard hose traveler when the cantilever is lengthened,the strength and stiffness of the double spraying gun supporting structure are analyzed by using the finite element model built based on ANSYS. Firstly,the ultimate cantilever length of single cantilever beam bracing structure is analyzed. On the basis,the single cantilever beam bracing structure is improved into truss type cantilever beam bracing structure. Then the new structure is analyzed by ANSYS. The results show that the limiting length of original structure is 3.4 meters,while the new is 21 meters,indicating that the improved support structure makes the cantilever length increase significantly. Finally,the truss type cantilever beam supporting structure is manufactured based on ANSYS,which has been applied in practice. At the same time,the results of this study can be used to guide users to manufacture different lengths of double cantilever supporting structures.

Precise control of irrigation precision and water and fertilizer ratio in agricultural irrigation can greatly improve the utilization rate of water and fertilizer. Therefore,based on the advantages and disadvantages of traditional PID control and Fuzzy-PID control,the Fuzzy- PID control optimization based on PSO was conducted. The control algorithm can effectively solve the problems of nonlinearity,time - variability and hysteresis in greenhouse irrigation control. The experimental results show that,compared with the traditional PID control,the rise time of the system is reduced by 4.10 s,the overshoot is reduced by 14.57%,and the adjustment time is reduced by 27.4 s.Compared with Fuzzy-PID control,the rising time is reduced by 4.30 s,the overshoot is reduced by 0.37%,and the adjusting time is reduced by 20 s. The system has the advantages of quick response,high matching accuracy and stability,and has certain application value.

In order to better analyze the institutional innovation path of farmers water use cooperation from the perspective of public policy， the individual equilibrium，collective equilibrium and water use game of farmers water use cooperation are analyzed with the game theory． Based on the analysis of individual equilibrium，the paradox of government punishment and collective equilibrium，the results show that: ① individual farmer water user has the behavior of“free riding”，and cannot achieve cooperation in irrigation． ② from the perspective of public policy，the government will not consider the choice of punishment strategy to promote water use cooperation among farmers． ③ the collective equilibrium utility of farmers water use cooperation is greater than the individual equilibrium utility． Therefore，from the perspective of public policy，the government has incentives for institutional innovation，and the institutional innovation path of water use cooperation is reflected in the following aspects: reducing the transaction cost of farmers water use cooperation，reducing the behavior of“free riding”and ensuring the realization of the benefits of cooperation． The corresponding strategies can be summarized as establishing water use cooperative organization for farmers，exploring property right reform and increasing capital input．

According to GB/T 50485－2009 Technical Specification for Micro－Irrigation Engineering，the common hydraulic calculation of pipeline network in micro－irrigation engineering design is based on the pipeline operation scenario under the most worst hydraulic running conditions，requiring that all flow variations of the emitter should not exceed 10% for the calculation，assuming that the lateral＇s flow is the sum of all flow of the emitters installed on it to be analysis and calculation． Different from this，this paper recommends a new method which does not calculate the total number of emitters and total flow of lateral pipe when irrigation，but based on the deformation of the specification formula of ( 3．2．3－1) of GB/T 50485－2009，the concept of controlled area of lateral irrigation or controlled area of emitter is put forward， and the calculation method of the total flow of lateral controlled area or total flow of emitters according to their controlled area is put forward． A practical method for calculating hydraulic analysis flow of pipeline network for system design is introduced，which meets the requirements of engineering calculation accuracy．