In order to explore the appropriate automatic irrigation and fertilization system of solar greenhouse in Tianjin，the conventional manual irrigation mode is taken as comparison，and the influence of automatic irrigation and fertilization model，which is based on the cucumber water requirement rule，on the yield of cucumber and the water and fertilizer utilization efficiency is studied． The results show that: compared with manual irrigation and fertilization mode，the automatic irrigation and fertilization mode can save water by 22．4% and fertilization by 30．4%; the single fruit weight and yield of cucumber is enhanced significantly with the guarantee of cucumber normal growth，the yield of marketable fruit is enhanced by 11．1%，and the irrigation water utilization efficiency and fertilization production efficiency is enhanced by 43．6% and 60．0%，respectively． So using the automatic irrigation and fertilization equipments to conduct the water and fertilization management based on cucumber water and fertilization requirement rule can be used as an effective approach to enhance the cucumber yield and water and fertilization utilization efficiency

In order to improve the quality and effect of the seasonal frozen distractions in spring and winter storage irrigation，a series of experiment during the seasonal frozen distractions has been conducted，and a lot of soil infiltration data under nature conditions are obtained． By fitting the Philip infiltration model parameters，a predictive model based on BP neural network is established，and the goal of using basic physical and chemical parameters of the surface soil，including bulk density of soil，clay content，silt particle content，moisture content，irrigation water temperature and soil temperature，to forecast the parameters of Philip model，which are steady infiltration rate and sorptivety parameters，is achieved． The average relative error between the predicted and measured values is less than 7%． The study results show that it is feasible to use the soil conventional physical and chemical parameters to predict the soil water infiltration parameter in Philip model． The research can provide strong support for obtaining parameters of the seasonal freezing and thawing of soil irrigation techniques．

The experiment uses thermal diffusion technique to measure the apple tree stem flow rate to study the daily change rule of apple tree stem flow rate under different treatments，including three water storage pit irrigation treatments，in which the upper and lower limits is 70% and 100%，60% and 90%，50% and 80%，respectively，and the surface irrigation treatment． And the effects of water system and meteorological factors on the stem flow rate are also analyzed． The results show that daily variation of the stem flow rate under different irrigation treatment in different growth period has the same trend，namely first increasing then decreasing． Through the analysis of the differences between different processing treatments，it is found that the second water storage pit irrigation treatment is a relatively reasonable irrigation scheme． With regard to the influencing factors，the leaf water potential is negatively correlated with the stem flow rate，the soil-flow rate is positively correlated to the stem and leaf water potential gradient． Through regression analysis，the regression equation among the stem flow rate and the solar radiation，air temperature and air relative humidity is established．

Using the method of tensiometer，the matrix suction of 5 kinds of sand，including gravel sand，coarse sand，medium sand，fine sand，silty sand，under different water content are researched experimentally，and the data is fitted and verified by three degree polynomial and Van Genuchtenmodel． The results show that: the soil water characteristic curve of fine sand shows“S”type curve，while that of gravelly sand，coarse sand，medium sand，silty sand shows“L”type curve; under the same water content，the order of the matrix suction from large to small is silty sand，fine sand，medium sand，coarse sand，gravelly sand; the Ｒ2 value and PBIAS value for the fitting results of three degree polynomial is 0．982 7～ 0．998 3，－0．119 8 ～ 0．342 7，respectively; while the Ｒ2 value and PBIAS value for the fitting results of Van Genuchten model is 0．931 0～ 0．992 6，－2．083 5～ 5．256 7，respectively; the fitting effect of the three degree polynomial is better than that of the Van Genuchten model．

In order to grasp the soil moisture diffusion regularity in different site types of root irrigation and drip irrigation． Some experiments with different gradients are conducted． The methods of digging profile and intuitive observation are used to study the vertical and horizontal diffusion regularity of soil moisture of root irrigation and drip irrigation in different site types． The results shows that: The soil moisture vertical diffusion of the root irrigation and drip irrigation in aeolian sandy soil is significantly less than the horizontal diffusion，the irrigation time has a negative correlation logarithmic relationship with the rate of diffusion． The soil moisture vertical diffusion of root irrigation in sandy loam soil is significantly less than the horizontal diffusion． The soil moisture vertical diffusion rate of drip irrigation is greater than the horizontal diffusion，but the difference is not obvious． The irrigation time has a negative correlation logarithmic relationship with the diffusion rate of the root irrigation and drip irrigation． The vertical diffusion and horizontal diffusion of the early root irrigation in gray-brown desert soil is the same level，but with time increases，the horizontal diffusion rate is greater than the vertical diffusion． The vertical diffusion rate of the drip irrigation is greater than the horizontal diffusion，but the difference is not obvious． Irrigation time also has a negative correlation logarithmic relationship with the diffusion rate． Overall，whether for the vertical or horizontal diffusion rates，the order of the regularity in different soil site types of the root irrigation from large to small is as follows: sandy loam soil，aeolian sandy soil，gray-brown desert soil． The order of regularity in different soil site types of the drip irrigation from large to small is as follows: gray-brown desert soil，aeolian sandy soil，sandy loam soil． The diffusion regularity of two irrigation modes is not the same．

For the protection of agricultural water and reducing invalid evaporation in Xinjiang，a kind of water evaporation inhibitor is developed． Hexadecanol and propanol are used as base，the influences of the compositional ratio，ultrasonic intensity，time and other factors on the inhibitory effect are discussed，and the preparation programme of water evaporation inhibitors is established． The specific programs is that: the scale of hexadecanol to propanol，AEO ，water，petroleum ether is 0．35 ∶ 1 ∶ 0．33 ∶ 12 ∶ 15，and the ultrasonic treatment apparatus operate 20 minutes with 20% of the working-intensity． The molecular membrane formed by the inhibitor has a good performance in 72 h． Promoting the use of the inhibitor is of great significance for reducing the water resources loss in arid regions and can bring huge economic and social benefits．

This purpose of the paper is to analyze the seedling germination rate，canopy growth and root growth of potted plant cotton under the condition of different salinity brackish water and reclaimed water，and to the application technology of the brackish water and reclaimed water for cotton irrigation． The experiment sets two factors of irrigation water and water quality，the effects of irrigation amount and water quality treatment on the seedling rate，canopy growth and root growth of potted cotton are studied． The results show that the rate of seedling emergence ，canopy growth and root growth decrease with the decrease of irrigation amount; 2 ～ 4 g /L brackish water and reclaimed water treatment promote seedling emergence，the treatment of higher than 4 g /L brackish water inhibits seedling emergence; canopy growth and root growth decrease with the decrease of irrigation amount; when the ambient temperature is low，the 2 ～ 4 g /L micro salt water and reclaimed water treatment can promote the growth and root growth of the canopy; when the ambient temperature is high，the 2～ 6 g /L slightly saline water treatment inhibits the growth of canopy and root growth; the regeneration water treatment promotes the growth of the canopy． The study provides reference for the application of brackish water and reclaimed water for irrigation of cotton．

In order to provide theoretical basis for maize drought-resistance，an experiment is conducted to study the influence of water stress at different growth period on the agronomic traits of maize． By water stressing the maize in seeding stage，jointing stage and tasseling stage and measuring the plant height，ear height，leaf area and panicle traits，the difference of the agronomic traits of maize before and after full irrigation and fertilizing cycocel is compared． Jensen model，which has applicability in evaluating the relationgship between crop yield and water，is used to find the water sensitivity index at each growth stage． The experiment result show that the plant height reaches its maximum after spinning and water stress has the greatest restraining effect on the plant height，ear height and leaf area in jointing stage，while in tasseling stage water stress has greater effect on the agronomic traits and yield of maize．

Aiming at the serious problems of soil and water loss and the lack of agricultural water of the slope farmland in the northeast black soil region，the research is carried out to discover the effect of biochar on the soil and water conservation and the crop yield increasing and to seek the most appropriate amount． In 2015，different amount of biochar was put in the 3°slope farmland in the Hongxin farm，Bei＇an agricultural reclamation，the branch of Heilongjiang to find the changes of the soil water dynamics，surface runoff，soil erosion，yield and water use efficiency in the growth period of soybean． The results show that: biochar has favorable effects on the soil and water conservation，water saving and yield increasing of soybean on the slope farmland． On one hand，the more amount of biochar is applyed，the more obvious the effect of soil and water conservation is; on the other hand，the most optimal amount of biochar is 75 t /hm2 for the yield and the water use efficiency of soybean．

Aimed at the bottleneck problems of drought，water shortage，strong evaporation and low irrigation water use efficiency in northwest yellow river irrigation district，a comparative test for shallow-embedded drip irrigation maize is conducted in Tongxin County of Ningxia by four kinds of contrast test planting double row by plastic-film maize，including shallow-embedded drip irrigation underfilm ( UF) ，shallow -embedded drip irrigation film-side ( FS) ，shallow-embedded drip irrigation no film ( NF) ，outdoor drip irrigation ( CK) ． The experiment results show that: the average temperature of film mulching treatment is 2．4 ℃ higher than that of no film treatment; the most obvious temperature difference in daytime is between 14 ∶ 00－16 ∶ 00 and the maximum temperature difference is 2．7 ℃ ; the temperature has the greatest effect on seedling; the sprout time in the area by UF is one day earlier than in the area by FS and three days earlier than in the areas by NF and CK，respectively． The above-grounddry matter accumulation in the areas by UF，FS and NF are increased by 9．7%，6．8%，4．2% as compared with the area by CK． The leaf area index at mature period in the areas by UF，FS and NF are increased by 18．9%，14．4%，4% as compared with the area by CK，and the yield in the areas by UF，FS and CK are increased by 12．9%，8．2%，2．6% as compared with the area by CK．

Using the remote control intelligent system，through soil infiltration experiments in the pumping irrigation area and based on two soil types，this paper analyzes the soil infiltration rate，wetting front and time under different water pressure and depth of buried depth and summarized the changing law of soil infiltration under different outside condition to supply scientific base for the water and soil conservation and the improvement of soil water productivity． The study results show that: the water pressure and the buried depth of drip irrigation belt have significant influence on the soil cumulative infiltration and infiltration rate; the cumulative infiltration increases with the increase of the water pressure increased; the water pressure can enhance the migration rate and distance of soil moisture in different directions; when the water pressure is 0．2 MPa，the wetting front can reach the largest migration distance in each direction; the buried depth of drip irrigation belt also has effect on the cumulative infiltration amount and infiltration rate of soil; when the buried depth is 10 cm，the cumulative infiltration reaches the maximum and the soil surface is not easy to evaporate．

In order to make irrigation scheduling of mulch-drip irrigation in the greenhouse more reasonable，an experiment was carried out in this paper． Cucumber was taken for example，and at its fruiting stage，four irrigation frequencies ( with intervals of 3，6，9，and 12 days，respectively) in mulch-drip irrigation were controlled，while local furrow irrigation was used as check treatment． The effects of irrigation frequency on the growth ( plant height，stem diameter，and leaf number) and yield were studied and the results showed that，compared to the traditional furrow irrigation，cucumbers grew better and got higher yields under mulch-drip condition． Between drip irrigation treatments，the higher irrigation frequency，the better cucumber grew with higher plant height，larger diameter，and more leaves，also the earlier cucumber fruit reached maturity． However，the effect of irrigation frequency on yield was not obviously，and the differences between treatments were not significantly ( p＜0．05) ． Compared comprehensively，irrigation every 6 days had a better plant type and highest yield of 112．4 t /hm2 ，besides that，its workload was acceptable，therefore，it was recommended as a suitable irrigation scheduling for mulch-drip irrigation in greenhouse．

In this paper，the correlation coefficient and the scatter slope method is used as evaluation tool，the Heihe Ｒiver Basin is taken as the study area，and the measured precipitation data in 25 hydrological stations is used to verify the accuracy of meteorological precipitation data on the year scale，month scale，and day scale． The results show: on the whole，the yearly and monthly precipitation data of the meteorological satellite has good correlation with the site observed precipitation data，the correlation coefficient can reach 0．962 on the month scale， the data accuracy is high，the value of the meteorological satellite data is a little lower than that of the site observed data，and the difference is small; while the correlation between the daily precipitation data of the meteorological satellite and the site observed data is bad，the data accuracy is low，and the difference is big; regarding to a single site，the correlation coefficient of most of the sits are high，but the difference is big．

In the field trials，the saline-alkaline tolerance sweet clover is selected as experiment materials，the change characteristic of water content，EC and pH of the soil profile ( 30 cm in horizontal direction and 100 cm in vertical direction) under drip irrigation under the cultivation patterns of flat planting and ridged planting with 50% of the surface evaporation amount of E20 evaporation pan per 3 days as irrigation index，is analyzed． The results show that EC and pH of ridged planting cultivation pattern are fallen more obviously than flat planting; the average EC in the layer of 0～ 60 cm under dropper declines by 37．4% and 21．8%，respectively，for ridged planting and flat planting than that before irrigation; ridged planting pattern has obvious leaching effect on the layer of 0 ～ 40 cm under dropper，the average EC declines by 52．4% than that before irrigation; flat planting pattern has obvious leaching effect in the layer of under 0～ 20 cm dropper，the average EC declines by 30．8% than that before irrigation．

Ｒecurrent neural network ( ＲNN) model has recently demonstrated state-of-the-art performance in many tasks． This paper used recurrent neural network with long short term memory( LSTM) unit to model and back-propagation through time( BPTT) algorithm for updating network＇s weights to deal with the problem of long-term rainfall forecasting，which solved the problems of high dimension，nonlinear and local minima． Finally，three networks，feed-forward neural network( FNN) model，wavelet neural network( WNN) model and auto-regressive integrated moving average( AＲIMA) model，are also provided for comparison． Simulation results demonstrate that recurrent neural network model outperforms the others networks，the training results are close to the actual value，the prediction accuracy is higher． The results provided important scientific basis for agriculture water management，rational irrigation system decision．

In order to achieve comprehensive and simple qualitative and quantitative water quality evaluation，the improved water quality identification indexes method is adopted to evaluate the water quality of Jilin province section of Songhua river basin based on the data of six segments during 2005－2014．The results show that the potassium permanganate index is the main pollution indicators，but the comprehensive water quality can meet the requirements of functional areas． At the same time，the Spearman rank correlation coefficient method is applied to analyze the water quality variation trend of the three segments during the past ten years． The results show that the water quality of all segments is improved intensively． This method can be used not only for single and composite indicator type comparison，but also for the comparison in the same category water quality，as well as has higher application value．

In order to solve the problems of the diversity and incompatibility of water quality index in water quality evaluation of，a water quality assessment method is proposed based on the projection pursuit method with the improved firefly algorithm ( FA) ． Based on the classification standard of surface water environment，the projection index function is established． With the optimization of the improved firefly algorithm，the searching step length is reduced gradually，better local search ability at the later stage is gained，the best projection direction is gotten，and the correct，objective and comprehensive evaluation results reflecting the true water quality is acquired． The Taihu lake water quality data is comprehensively evaluated with this method and the evaluated results are compared with those of the comprehensive scoring method ( F method) ． The results approve that the assessment method matches the actual local water quality circumstances better and are clearer in water quality hierarchy．

In order to prevent the soil secondary salinization，the soil salt accumulation and movement trend in cotton field is analyzed by studying the change characteristics of soil salt on the beginning and ending of the growth period in typical oasis arid areas．The results indicate that: the soil salt change trend during the beginning and ending of growth period is mainly same in studying area，and presents a trend that more deeper of the soil layer，more higher of the soil salt content; the accumulating level of the soil salt in the soil profile is larger at the beginning than the ending of the growth period; a weak accumulation trend of salt in soil surface presents in the soil depth of 0～ 20 cm at the beginning and ending of growth，which can be seen as non-salinization soil and light saline soil and can meet the requirement of cotton seed germination and later growth． At the beginning of the growth period，soil salt content in 100 cm soil depth keeps about 7 g /kg ，which belong to mid-salinization soil and has great potential to result in the soil secondary salinization． Snow that accumulated in cotton field and the irrigation in autumn are useful for leaching the soil salt and preventing the soil secondary salinization．

The general situation of groundwater resources in Beijing is summarized in this paper，the changes of temperature，precipitation and evaporation characteristics in nearly six decades are analyzed． The results show that the temperature increases with fluctuation with a mean increment of 0．08 ℃ /a，the annual precipitation gradually decreases with a mean rate of －3．45 mm/a． The amount of evaporation on surface water decreases with a mean rate of －8．04 mm/a． Precipitation decrease and groundwater overdraft bring adverse effects，leading to continually descease of groundwater level and dewatering of some shallow aquifers． Depletion of groundwater storage is up to 65．82×108 m3 from 1991 to 2013，about 4．39×108 m3 /a year on average． Groundwater quality becomes poor with the change． Annual mean evaporation of groundwater is 4．95×108 m3 /a from 1960 to 1980，which reduces to 0．44×108 m3 /a later in 2001． The influence of temperature on groundwater is indirect and weak．

Based on the meteorological data of middle plain irrigation area of the Manasi Ｒiver and its surrounding 24 meteorological stations in 2013，subsection single value average method was adopted to define the cotton crop coefficient． The reference crop method was used to calculate the cotton water consumption intensity at different development stages of each irrigation area． Combined with ArcGIS spatial interpolation，the irrigation water consumption variation was analyzed at different growth stages and irrigation spatial scales，then the design water consumption intensity of cotton was determined． The results show that: the cotton water consumption intensity at different growth stages increased at first，then decreased． And the order from large to small is blooming period ( 5．64～ 6．84 mm/d) ，bud stage ( 3．74～ 4．70 mm/d) ，boll opening stage ( 2．00～ 2．50 mm/d) ，seedling stage ( 1．62～ 1．76 mm/d) ; the average water consumption intensity of cotton in the whole growth period presented the increasing trend between 3．45～ 3．98 mm from southwest to northeast; the design water consumption intensity of cotton should be selected between 5．69～ 6．45 mm

According to the measured data of winter wheat soil moisture and nutrients in the growth period in Linfen city，the insufficient irrigation forecasting model was proposed based on the dynamic irrigation lower limit value method and combined with the crop growth model． The forecast model was applied to Linfen city for the irrigation forecast in the growth period of winter wheat in the year of 2008－2009，2009 －2010，2010－2011，2011－2012，2012－2013 and 2013－2014． The study results that: compared with the traditional irrigation mode，all the yield and benefit of the six years under the optimized irrigation system based on the above method increase by a different degree． The average rate of production and benefit increase is 9．94% and 17．50%，respectively．

Wensu irrigation ecological forest project is built in Wensu County of the Gobi Desert land ecological forest project，become a successful example of application of drip irrigation technology in land desertification． The ecological function and economic function of this project are set in one，afforestation area of 7 247 hm2 ，fruit trees using drip irrigation． This paper uses the LFA principle，from the project objectives、function /effect、output and input 4 level measures to establish the evaluation system，then，consideration and evaluation the ecological benefits，economic benefits，social benefits and the utilization of water resources，to provide reference for related projects． 

Virtual water trade，as a strategy to solve the water shortage problem，has attracted more and more attention． The quantization of virtual water trade patterns and analysis of driving factors of virtual water change in this pattern is a breakthrough new idea of water management． This paper firstly uses input-output model to calculate the inflow and outflow of virtual water of the 8 industries of China in 2002 to 2012 and analyze the current virtual water trade pattern of China，and then uses the method of SDA to analyze the driving factors of virtual water change and the change of their contribution． The results show that: The virtual water trade outflow exceeds the inflow，the virtual water trade of manufacturing and agriculture industry is the biggest part of the whole virtual water trade and have great influences in the whole virtual water trade pattern． The contribution of scale factor to the change of virtual water trade changed from negative to possible，while the contribution of technology and structure factor is positive． Acknowledging the pattern of the virtual water trade and exploring virtual water policy is an important way to achieve optimal allocation of water resources in China and it offers a new perspective for China to ease water conflicts and solve water shortage crisis．

In view of the large time delay of the existing remote irrigation system based on ZigBee，a drip Irrigation and Fertilizer system based on 6LoWPAN is designed on the basis of Considering the realization of automation and precision of modern agriculture and combining with the rapid advancement of 6LoWPAN． By adopting the 6LoWPAN protocol，this system can realize point-to-point communication between IPv4 /IPv6 and real-time monitoring of temperature and humidity of the soil． According to the requirement of different crops to the humidity， the user can control the electromagnetic valve to carry on the irrigation of water or fertilizer． This paper elaborates the hardware structure， software architecture implementation process，and LabVIEW software-perception system master computer management interface development． The experimental results indicate that 6LoWPN and IPv4 /IPv6 network can communicate with each other，the system can accurately obtain the soil humidity and ambient temperature data，the electromagnetic valve can be remote control for irrigation through the upper management software to keep the humidity within the set range． The system test results show that the drip irrigation system based on 6LoWPN is less time delay than the drip irrigation system based on ZigBee，which is therefore of great promotional value．

1． Ｒesearch Center of Fluid Machinery Engineering and Technology，Jiangsu University，Zhenjiang 212013，Jiangsu Province，China; 2．Changzhou Institute of Technology，Changzhou 213002，Jiangsu Province，China)