By conducting the indoor drip irrigation test of sandy loam with different initial soil moisture content and different emitter flow，the soil hydrodynamic parameters are determined and the applicability of the HYDＲUS model is verified． The HYDＲUS model is used to simulate the process of soil water transport by point source drip irrigation with different irrigation upper and lower limits． The results show that when the field water holding capacity is the upper limit of irrigation water，the actual volume of soil moist body is larger than that of planned moist body，and a small lower limit of irrigation water is favorable for controlling irrigation water in planned moist body． When the lower limit of irrigation water is 50% of θFC，60% of θFC and 70% of θFC，the upper limit of irrigation water for controlling the actual volume of moist body is 81% of θFC 85% of θFC，and 86．5% of θFC ． It is verified by simulation that no irrigation water is transported to the planned wetting outside the body at the end of drip irrigation

The water-saving irrigation model of spring wheat in Ningxia Yellow River irrigation area was studied by DSSAT model simulation and field experiment. The orthogonal test design method of 4-factor 2-level L16（215）was adopted both in simulation and field experiment. The 10 growth parameters and 7 genetic parameters of spring wheat varieties (Ningchun 50#) suitable for the DSSAT model in Ningxia yellow irrigation area were screened and determined. Combined with the main field experiments, 16 different irrigation scenarios of spring wheat yield and irrigation water use efficiency were simulated, and the applicability of DSSAT4.7-CERES-wheat model was evaluated. Comprehensive analysis of simulation and field test results show that：(1) the Relative Root Mean Square Error（RRMSE），Absolute Relative Error（ARE）and Average Error （ME）of the yield of spring wheat variety NingChun 50# between simulation and field test are 10.32%, 9.79% and 2.23 kg respectively. Showed that the model to simulate irrigation mode optimization effect is better. Under normal field management conditions, irrigation times and irrigation time have significant effects on spring wheat yield and irrigation productivity. (2) Under nomal climate conditions spring wheat water-saving irragation scheme in the irrigation area of Ningxia were non-irrigation at third water（A1B1C2D1） or fourth water（A1B1C1D2）, the yield are 5907 kg/hm2 and 6102 kg/hm2 respectively；and the irrigation water use efficiency are 1.41 kg/m3 and，1.45 kg/m3 respectively. Two times of irrigation A1B1C2D2 (first and second irrigation ) can be used when the rainfall tends to be plenty，which can achieve high yield and water production efficiency (6368 kg/hm2，1.93 kg/m3 respectively). The conclusions of this study can provide the basis and reference for the decision of water-saving irrigation scheme for spring wheat in Ningxia Yellow River irrigation area.

In order to explore the high － quality and high － efficiency water － nitrogen model under the conditions of brackish water drip irrigation，three irrigation levels，including low water irrigation ( W1: 2 325 m3 /hm2 ) ，medium water irrigation ( W2: 2 850 m3 /hm2 ) and high water irrigation ( W3: 3 375 m3 /hm2 ) ，were set up; three kinds of nitrogen levels，including low nitrogen ( N1: 525 kg /hm2 ) ， medium nitrogen ( N2: 750 kg /hm2 ) and high nitrogen ( N3: 975 kg /hm2 ) were set up． The effects of water－nitrogen interaction patterns on Lycium Barbarum growth and soil environment are demonstrated through field trials． The results show that: the growth rate of plant height， new shoots and crown width are larger in the spring shoot growth period，while the ground diameter growth rate is larger in the fruit expansion period and the growth characteristics are optimal under W2N2 level． Through the analysis of the difference of plant height，it is concluded that the insufficient irrigation and fertilization have a great influence on the plant height，while the suitable irrigation and excessive irrigation and fertilization have little effect on the plant height． The spatial variation of soil water content and soil conductivity shows that under the W2 and W3 irrigation levels，the application of nitrogen fertilizer will increase the shallow soil moisture content，while the excessive fertilization will have the opposite result． And the W2 level can bring most of the salt to the 40～ 60 cm soil layer，so that the upper main root zone presents a low salt state，which is conducive to the growth of the plant． Therefore，the appropriate combination of water and fertilizer is W2N2．

Owing to large quantity of retreating water in Qingtongxia Irrigation Distract，it is difficult to predict the retreating water． Based on the previous research，through applying the improved natural watershed hydrological SWAT model and setting up different scenarios ( different water－saving schemes) based on SWAT model，the quantitative effects of water cycle transformation in irrigation district are analyzed． The results under different irrigation treatments show that: the actual evapotranspiration from high to low are ranked as high water irrigation， middle water irrigation，low water irrigation． The actual evapotranspiration increases with the increase of irrigation amount． The water leakage in the root region from high to low are ranked as high water irrigation，middle water irrigation，low water irrigation． The amount of water leakage in the root region increases with the increase of irrigation amount． The contribution of surface runoff to the Yellow Ｒiver from high to low is ranked as high water irrigation，middle water irrigation，low water irrigation． It becomes larger with the increase of irrigation amount． There is no difference in the contribution of underground runoff to the Yellow Ｒiver，and the correlation between this value and irrigation amount is not obvious． The study result provides technological support for the further development of water －saving irrigation in irrigation district．

The effects of different irrigation treatments on the water and nitrate nitrogen transport in potato root zone and the effects of different irrigation treatments on potato yield were studied through field sub－film drip irrigation experiment to provide a theoretical basis for the prevention of leaching and leakage of nitrate in soil and the improvement of soil water and fertilizer use efficiency in arid areas of Ningxia． The irrigation volume of 900，1 260 and 1 620 m3 /hm2 are selected as variables and the randomized block test method is used in the test． The test results show that the soil moisture content increases with the increase of irrigation quota and the depth of soil layer; with the process of the days after irrigation，the soil moisture content of different treatments decreases continuously; the water content of surface soil ( 0～ 20 cm) increases with the increase of irrigation quota，and the soil moisture content of 30～ 40 cm decreases continuously; the decreasing range of soil moisture content of 50～ 100 cm soil layer decreases with the increase of irrigation quota; the nitrate content of 30～ 50 cm soil layer is lower than that of 0～ 20 cm soil layer，and the content of nitrate nitrogen in 60～ 100 cm soil layer fluctuates from 0 to 0．11 mg /kg with the basis of the 0．2 mg /kg; irrigation amount can increase the yield of potato in a certain range，but when the irrigation water is more than 1 620 m3 / hm2 ，the yield is negatively correlated with irrigation amount． Under the test condition，when the irrigation quota is 1 260 m3 /hm2 ，the potato yield is the highest，up to 25．88 t /hm2 ，and the soil moisture content and nitrate nitrogen content in different depths are the optimal water demand for potato growth and development． 

In view of the uneven distribution of sprinkler and irrigation with low quality problems，through introducing the pulsating water pressure water supply technology into the slope sprinkler irrigation，the effect of terrain slope on nozzle flow，range，wet area，single nozzle water distribution and combination nozzle water distribution and uniformity are analyzed for the Ｒainbird LF1200 sprinkler． The results show that: for a single nozzle，the difference of spraying radiu between uphill and downhill using pulsating water pressure irrigation is about 2．3m; the pulsating pressure amplitude has a significant influence on the spraying radius; for pulsating pressure irrigation，the amplitude is recommended to use a larger value within the normal working pressure range of the nozzle; the uniformity of the water distribution of the single nozzle is about 56%，and the influence of pulsating hydraulic parameters on water distribution and uniformity of sprinkler irrigation is not significant; under the condition of combined sprinkler，the uniformity of the triangle arrangement and the rectangular arrangement is higher than that of the square arrangement． Considering the engineering investment and the uniformity of water distribution，the distance between the nozzle is suggested to be 1． 0 ～ 1． 2Ｒ ( Ｒ is the spraying radius of sprinkler in the flat land) for triangle arrangement． For rectangular arrangement，the slope spacing should be 0．6Ｒ ～ 0．8Ｒ，and the vertical slope spacing should be 1．0～ 1．2Ｒ．

The effect of fertilizer sand (quality of 3% urea and sediment of 2g/L) and fertilizer water (quality of 3% urea) on the blocking of microporous ceramic irrigation emitters were studied, in order to reveal the mechanism and influence of sand-fertilizer on microporous ceramic irrigation emitters in the process of integrated water and fertilizer irrigation.The composition of the sediment in the emitter was analyzed by XRD. When 75% of the average relative flow rate is used as the criterion for clogging, the results show that: under the condition of fertilizer-sand coupling irrigation, after irrigation for 200h, the micro porous ceramic irrigation emitters will be seriously blocked, but under the fertilizer and water irrigation condition, the blockage is not serious.During the fertilizer-sand irrigation, the sediment particles will gradually form a sediment film on the inner wall of the micro porous ceramic irrigation emitter and will not enter the micropores of the micro porous ceramic irrigation emitter.The main components of the sediment film are SiO2, calcium carbonate and calcium silicate. .The formation of the sediment film is the main cause of blockage of the micro porous ceramic irrigation emitter.

This paper aims to achieve quantitative prediction of transpiration rate under water storage pit irrigation ( WSPIT) ． Based on the BP neural network optimized by genetic algorithm ( GA) ，Levenberg algorithm ( LM) and additional momentum algorithm ( AM) ，the GA－ BP－WSPIT model，LM－BP －WSPIT model and AM－BP －WSPIT model are established，respectively． Temperature，atmospheric relative humidity，photosynthetically active radiation，and vapor pressure deficit are taken as input，and transpiration rate under the water storage pit irrigation is taken as output． The GA－BP－WSPIT model，LM－BP－WSPIT model and AM－BP－WSPIT model are validated by test data． The results show that the mean absolute percentage error of GA－BP－WSPIT model，LM－BP－WSPIT model and AM－BP －WSPIT is 2．17%， 3．56% and 5．68%，respectively． The GA－ BP － WSPIT model has the best precision． The GA－ BP － WSPIT model is recommended for quantitative prediction of apple tree transpiration rate under water storage pit irrigation．

In order to verify the effects of different irrigation methods on the soil quality of kiwifruit plantation，three irrigation modes，micro sprinkler irrigation，surface irrigation and drip irrigation，were set up from 2016 to 2017 in Mei County and Yangling kiwifruit plantation in Shaanxi province． The soil bulk density，field capacity，soil porosity，organic matter，available potassium，available phosphorus and alkali－ hydrolyzed nitrogen in 0－50 cm soil layer were statistically analyzed by SPASS 18． And then the soil quality of different irrigation treatments was evaluated by soil quality index． The results show that: ① there is no difference in soil bulk density，soil porosity and field capacity between micro sprinkler irrigation and drip irrigation treatment in 0 ～ 50 cm soil layers，but the above indexes of micro sprinkler irrigation and drip irrigation are significantly better than those of surface irrigation treatment in 0～30 cm soil layer ( P＜0．05) ; ② compared with the fertilization standard of the kiwifruit orchard，the 3 treatments are both deficient in organic matter and alkali hydrolysable nitrogen，and the available potassium and phosphorus in the treatment of micro sprinkler irrigation and surface irrigation are exceed the balanced value in the 0～50 cm soil layer; ③ soil bulk density and organic matter are comprehensive indexes to reflect the soil quality of kiwifruit plantation; ④ soil quality index of drip irrigation treatment is significantly higher than that of micro sprinkler irrigation and ground irrigation treatment ( P＜0．05) ，which is 1．21 ～1．81 times higher than that of both． Therefore，drip irrigation is an effective measure for sustainable land use in kiwifruit plantation． The study results are of great significance for screening of irrigation measures and providing a reference for the sustainable utilization of land．

Studyed the photosynthetic characteristics and physiological and biochemical characteristics under the pot conditions of natural drough forming a water gradient by using two-year-old Xinyang May peach as test material.The result showed that:the daily change of photosynthetic rate of Xinyang May peach was the largest at 8:00,then gradually decreased and dropped to the lowest at 14:00,then rebounded.There was a clear “lunch break”phenomenon;The photosynthetic rate of Xinyang May peach was closely related to transpiration rate,stomatal conductance,leaf temperature and intercellular CO2 concentration. When the relative soil water content was more than 55.7%,the main factor for the decrease of photosynthesis rate of Xinyang May peach was stomatal factor.When the relative soil water content was lower than 55.7%，the main factor for the decrease of photosynthesis rate of Xinyang May peach was non-stomatal factor.When the relative soil water content was more than 55.7%,the osmotic adjustment substance of Xinyang May peach was continuously accumulated and the cell-protecting enzyme system with SOD-dominated was enhanced,all of this were obviously improved the mechanism of drought resistance of Xinyang May peach.When the relative soil water content was lower than 55.7%,the water deficit was aggravated,the osmotic adjustment ability was weakened and the plasma membrane system was destroyed and peroxidized.

It is important to study the temporal and spatial distribution variation and prediction of water shortage risk for the rational exploitation and utilization of water resources and sustainable development of society in Yuxi． The fuzzy cluster analysis method is used to analyze the risk of water shortage in the districts and counties of Yuxi from 2005 to 2015 and the water shortage risk in 2020 and 2030 is predicted． The results show that the temporal heterogeneity of the water shortage risk in Yuxi prefecture－level city is remarkable; it increases originally and then decreases between 2005 and 2015; the risk of water shortages in the east is higher than that in the west; in 2020，the 2nd and 3rd grade risk is faced by the districts and counties in Yuxi of normal and low precipitation years; and the 4th and 3rd grade risk are for extremely low precipitation year; in 2030，the water shortage risk is the 2nd and 4th grade of normal and low precipitation years，and the 4th and 5th grade of extremely low precipitation year． Agricultural water consumption has the greatest impact on water shortage risk． However， ecological water consumption and effective irrigation area have not significant effect on the risk.

Aiming at the contradiction between temporal and spatial resolution of soil moisture monitoring，using the modified normalized vegetation index ( NDVI) as the indicator of soil moisture，this paper puts forward a new method of real － time and semi － quantitative monitoring of soil moisture during winter wheat growth period by using the shared meteorological remote sensing data with high temporal resolution． First of all，the winter wheat planting area was divided into regions，and the growth stages were also divided according to its phenological characteristics; Secondly，NDVI was calculated by using meteorological remote sensing data，and the NDVI was adjusted adaptively in each stage and region． The correlation analysis between measured soil moisture data and modified NDVI showed that NDVI could be used as an indicator of soil moisture． Finally，the temporal and spatial distribution of soil moisture of winter wheat，through compared with those of previous three year averages，was obtained by analyzing the difference between the modified NDVI and the annual mean value，and the result was in agreement with the actual observations． It is foreseeable that if there is a longer time series to accumulate，the temporal and spatial distribution of soil moisture in the wheat field can be obtained through compared with the perennial year． The results show that the method proposed in this paper can be used to semi － quantify and quasi － real － time monitoring of soil moisture in winter wheat in the whole growth period． Moreover，remote sensing data are easy to obtain，almost no need of measured data，convenient calculation and low cost． So， it has important reference value for winter wheat farmland management and decision－making

In order to study the improvement effect of drip irrigation on saline land and rationally develop and utilize resources of saline land, this experiment used saline-alkali forage alfalfa as experimental material, with 12 mm as irrigation quota and once a week as irrigation frequency, studied the rule of soil water and salt transport in saline land before and after drip irrigation. The results showed that drip irrigation had good leaching effect on saline soil. After drip irrigation 24 hours and 72 hours , the conductivity and pH of the surface soil under drip emitter decreased by 72.2 %, 8.2 %, 74.7 % and 5.0 %, respectively, compared with that before drip irrigation. After drip irrigation, as the increase of time, soil moisture evaporation increased, the phenomenon of salt return was serious.

Scientific and objective evaluation on water resources carrying capacity is of great significance for rational and efficient utilization of water resources and promoting sustainable development of economy and society． According to the characteristics of water resources in arid areas and the actual situation of Tarim Ｒiver Basin，this paper establishes an evaluation system of water resources carrying capacity，which covers 4 aspects and 12 indexes． Variable fuzzy set theory and comprehensive weighting method are used to evaluate the water resources carrying capacity in the study area． The results show that: in 2015，the WＲCC of Aksu Ｒiver Basin and Tarim Ｒiver trunk reaches grade 2， and the WＲCC of Hotan Ｒiver Basin and Yeerqiang Ｒiver Basin has reached grade 2 ～ 3，if it continues to deteriorate，this will impede the sustainable development． By 2035，the WＲCC of Yeerqiang Ｒiver Basin and Hetian Ｒiver Basin will reach grade 2，indicating that the water resources composite system has a better trend and the WＲCC will be enhanced． The WＲCC of Tarim Ｒiver trunk reaches grade 2，indicating that the water resources system can support the local production，living and ecological water use． The evaluation results of the model are stable and accurate． The results provide an important reference for the optimal allocation of water resources in river basins．

Water resources are basic security for supporting regional economic and social development． Scientific and rational evaluation of water resources carrying capacity is of significance to achieve sustainable development of regional socio－economy． Based on the dimensions of “quantity，quality，domain，flow”，water resources carrying capacity evaluation index system was constructed． Aiming at the uncertainty problem of index quantification and classification of grades，the evaluating model of water resources carrying capacity based on normal cloud theory was established，and the sensitivity of index weight was analyzed by one－at－a－time ( OAT) ． The evaluating index system and model were applied to the assessment of water resources carrying capacity of the Yellow Ｒiver Basin in 2015． The results show that the water resources carrying capacity level eigenvalue of the Yellow Ｒiver Basin is 2．70，which is in the critical state of the third level; meanwhile，the water quantity carrying capacity is in Grade Ⅲ; the water quality，watershed and water flow dimension are Grade Ⅱ; except for Gansu， Ningxia，Shanxi and Henan province，which are in Grade Ⅱ，other provinces are in Grade Ⅲ; The evaluation results are consistent with the evaluation results of SPA－VFS and TOPSIS，which indicates that the evaluating index system and model based on “quantity，quality， domain，flow”are effective and feasible，and the results are reliable． This research result can provide multi－dimensional quantification of water resources carrying capacity evaluation system and method．

Considering that there are many problems in soil moisture collectors，such as bad compatibility，low precision，and poor stability， a portable multiple wireless communication interfaces soil moisture collector is designed． The collector，based on a frequency domain impedance transformation principle soil water content sensor and a digital temperature sensor，can measure soil temperature and moisture simultaneously． Its variety of communication interfaces is suitable for wireless transmission to different needs． GPS is used to obtain geographical location information． The measured soil information can be sent to mobile phones and remote servers via Bluetooth or GPＲS network． The data can also be directly stored in the local data logger． The experiment results shows that the portable soil moisture collector has advantages of fast response，high stability，low cost，etc． It can portably collect soil moisture and temperature，and transmit data through multiple channels

Abstract:In the process of irrigation forecasting, the soil moisture sensor should be used to monitor the soil moisture. The more the soil moisture sensor is buried in the same section, the higher the accuracy of the measurement. In practical applications, it is required to reduce the number of soil moisture sensors buried to reduce the cost of the system and to ensure a certain accuracy.In this paper, four test areas were selected, and the soil moisture data of five test depths measured by soil drying method were used in the depth of 0-100 cm soil layer.The correlation between the average water cut of 0-60cm and 0-100cm soil profile and the moisture content of the monitoring point was analyzed, and a comparison of different monitoring points and two monitoring points was set.The correlation coefficient (R2), average relative error (δR) and root mean square error (RMSE) of the average soil moisture content of the soil profile and the moisture content of the monitoring point were calculated. research shows:At a monitoring point, the water content at a depth of 40 cm can better reflect the average water content of the 0-60 cm soil profile, and R2 is above 0.95; the average moisture content of the 0-100 cm soil profile is reflected by the depth of 60 cm, and R2 can reach 0.93.At the two monitoring points, the water content at 20/50cm has the highest correlation with the average water content of 0-60cm soil profile, and R2 is 0.994; the average water content of 0-100cm soil profile is the highest correlation with the water content at 40/70cm. The average R2 of each test area was 0.965.

As one of the three ultra－large irrigation districts，the Hetao Irrigation District is an important commodity grain base of China． Currently，due to the increase of irrigation area and decrease of water supply from the Yellow Ｒiver，the contradiction between soil salinization and water scarcity is increasingly becoming outstanding． Mulched drip irrigation，an advanced water－saving irrigation technology， has been playing an important role in the agricultural water saving and saline －alkali soil improvement in arid areas in Northwest China． However，this technology is not very popularly applied and studied in the Hetao Irrigation District． Based on the current situation of agricultural water saving in the Hetao Irrigation District，in this paper，the study advance in mulched drip irrigation is summarized and its application prospects and future research in this irrigation district are mainly discussed．

Since the promotion of urbanization and large-scale water-saving irrigation, great changes have taken place in the Northwest Inland Oasis of China. Using Remote Sensing earth observation technology, the year of 1998, 2007 and 2017 image data (TM /OLI) were selected in the Shihezi region of Xinjiang, combined with Dimidiate Pixel model to estimate the vegetation coverage and vegetation changes, and calculated the transition matrix of vegetation cover area change in each year. The results showed that vegetation coverage in the study area in 1998, 2007 and 2017 were 52%, 60%, and 48%, respectively, which showed a trend of firstly increasing and then decreasing. The vegetation coverage areas of grade II and III were increased 1.17% and 1.56% per year respectively. The vegetation cover areas of grades I, IV and V decreased at an average rate of 0.05%, 0.26% and 0.75% per year, respectively. The area of vegetation degradation in this region was larger than the restoration area in the past 20 years. Based on the analysis of land, meteorological and hydrological data, we believe that the large-scale use of water-saving irrigation, over-exploitation of groundwater and the expansion of urbanization are the main reasons for vegetation degradation in the area.

Based on Fluent software，the porous media model and ＲNG k－ε turbulence model are used to simulate the flow field of torpedo screen filter with different sizes． The results show that the relative error of inlet and outlet head loss of 8－inch torpedo screen filter calculated by numerical simulation and actual test are 5．99% and 1．41%，respectively，which shows that the selected mathematical model has certain accuracy and reliability． The numerical simulation results of torpedo screen filter with different sizes show that the variation of flow field with different size is basically the same，and the change of pressure and velocity is basically the same; the filters with different sizes all have a most suitable working flow range． The experimental study further reveals the internal flow field variation of torpedo mesh filter with different sizes，and provides a reference for selecting the size of high efficiency and energy saving filter in practical application．

Field experiments were carried out in the Loess Plateau of Shanxi Province to obtain soil samples． The soil characteristics curves and physical and chemical parameters were obtained by laboratory tests． The Van －Genuchten prediction model based on support vector machine was established． The input variables were selected from five basic soil physical and chemical parameters ( soil clay，silt，bulk density，organic matter and total salt) ，and the output variables were parameters α and n of the Van－Genuchten model． The parameters of the curve Van － Genuchten model were predicted and good results were obtained． Under the support vector machine prediction model established in this paper，the average relative error between the predicted values and the test values of Van－Genuchten model parameters α and n are less than 4%，and the modeling and test samples have high precision． The research results will help to enrich the theoretical study of soil water characteristic curves in loess areas． 

There are many complex operating conditions, and multiple sources of water dispatch risk in long distance water transfer project. To ensure the safety of water dispatch, it is significant to take risk evaluation for long distance water transfer project. This paper summarizes the main risks that water dispatch is facing based on the actual situation of water dispatch including dispatch institution risk, dispatch personnel risk, dispatch technical risk and dispatch coordinate risk, in-depth analysis of various types of risk source project and proposed the new risk evaluation based on cloud model and possibility measures theory. The new evaluation model can not only show the fuzzy feature of grade, but also indicate random attribute of the degree by hyper entropy. Apply the model into risk assessment of the water dispatching. The results showed the model has strong adaptability, flexibility and high fitting accuracy.

To clearly detect the comprehensive benefits of drip irrigation under film technology，a set of comprehensive benefits evaluation model is designed． The evaluation index system of this model is divided into three layers，including the target layer，the criterion layer and the index layer． Thereinto，the criterion layer includes with three items，namely economic benefits，environmental benefits，social benefits and index layer． The criterion layer includes six items，namely net benefit of Mu ( Chinese agrarian unit of measurement) ，economic benefit cost ratio，average water content，rate of desalination，the effect of promotion of demonstration，and enhancing the new farmers' quality． The weight of each index is calculated by the analytic hierarchy process． Then the indexes are normalized by the gravity method． Finally，each merit and the comprehensive benefits are calculated by the linear mathematical model． Taking the typical drip irrigation under mulching film technology ( one from with two tubes) in the northern Xinjiang as research objects，and the typical crops of cotton as an example，two－year comprehensive benefits of the crops under the condition of drip irrigation under mulch are evaluated and compared． The final result is that: the comprehensive benefits of 2012 and 2013 were 0． 221 5，0． 325 3，respectively． Through analysis，the result can be got that: the precipitation amount and the fluctuations of cotton prices are the main factors which affects the change of the comprehensive benefits． It is believed that this research provides the modified direction for the promotion of benefits in the field of drip irrigation under mulch in the future． The results show that the evaluation model can evaluate the comprehensive benefits of drip irrigation technology comprehensively and objectively，and provide direction for the future development of drip irrigation．