In order to solve the problem of low decomposition，slow resolve of the straw and evaporation of soil water in Huang－Huai－Hai area，in this experiment，Zhengdan 985 was used as the test material and split plot design was adopted． The main plot was water retention agent，with the treatments of Application ( A1) and No application ( A2) ，the subplot was the mode of straw returning with the treatments of No returning to field ( B1) ，Smashing returning to field ( B2) ，and Smashing straw and composting agent after stacking for 5 days and scattering into the field ( B3) ． The effect of the interaction of straw return manner and water retention agent on the weight of dry matter， yield，the soil moisture and the water use efficiency was studied． After two years of experiments，the results showed that: the application of water－retaining agent increased the number of row grains by 1．6% ～ 3．5%，the yield by 3% ～ 7%，and the soil water content of 0～ 40 cm in the trumpeting stage，the milk stage and the mature stage significantly． Straw returning could increase the number of grains per ear and the hundred－grain weight，and increase the yield by 3% to 8%． The application effect of straw decomposing agent was more obvious，but there was no significant difference in soil water content and water use efficiency between treatment B2 and treatment B3．The application of straw decomposing agent and water retention agent significantly increased the grain number per spike，100 grains weight，the yield was increased by 10．1% and 16．9% respectively in the two years，and the water use efficiency was increased by12．3% and 18．8%． After straw returning， the application of straw decomposing agent and water retention agent could increase the dry matter accumulation in the middle and late stage of corn，increase the grain number per row and grain weight，so as to improve the yield，and increase the surface soil water and improve the water use efficiency． In summary，the application of straw decomposing agent and water retention agent after straw returning is worth of popularizing in Huang－Huai－Hai dry area．

In this paper,the salt absorption effect of atriplex canescens in the soil with different initial salt content and planting number was studied in order to provide an effective reference for the reasonable utilization of atriplex canescens to improve the soil environment in saline -alkali land. Pot experiment was used to plant seedlings with different number of plants in soil with initial salt content of 4.94,10.02,21.09 and 39.14 g /kg,respectively,which were labeled as soil A,B,C and D. Their growth status and changes in soil salt content were observed, and soil salt content was measured every other month during the growth cycle. The results showed that 2 plants planted in soil A had the best salt-absorbing effect,3 plants planted in soil B and C had the best salt-absorbing effect,and 1 plant planted in soil D had the best salt- absorbing effect,indicating that the different number of planted plants would affect the salt-absorbing effect of atriplex canescens on saline- alkali land. When one atriplex canescens was planted in each of the four soils,the salt absorption effect was the best in D soil,and the salt reduction rate reached 33.80% in the first month,but then the atriplex canescens withered. In the other three soils with different initial salt content,the atriplex canescens kept normal growth,and the salt-absorbing ability was as follows: B soil ＞A soil ＞ C soil. Soil salinity reduction rates were 23.25%,17.61% and 15.17%,respectively. Multiple comparison results showed that the atriplex canescens could grow normally in the soil with less than 2% salt content,and had certain improvement ability to the saline-alkali soil.

Based on the meteorological data of the Jingzhou Meteorological Station from 1953 to 2008,the ET0 values calculated by Penman -Monteith formula method were compared with those calculated by Hargreaves,Priestley-Taylor,Mc-Cloud and Irmak-Allen. The results show that the Hargreaves formula and Priestley-Taylor formula have the perfect applicability in Jingzhou area,the average relative error is about 10%,the correlation coefficient is more than 0.96,and the consistency index is more than 0.98,they can be directly used to calculate the local reference crop evapotranspiration. The average relative error of Mc-Cloud formula is more than 40%,and the correlation is poor, the consistency index is less than 0.90,and the correlation coefficient of average annual is less than 0.90. The Mc-Cloud formula is not suitable for the calculation of reference crop evapotranspiration in Jingzhou area. Irmak-Allen can be used to calculate the crop reference evapotranspiration in Jingzhou area with the revised formula as follows: ET'0IA = 1.095 7 ET0IA -9.020 1( P = 25%) ,ET'0IA = 1.137 5 ET0IA -12.29 9( P= 50%) ,ET'0IA = 1.124 4 ET0IA -12.056( P= 75%) and ET'0IA = 1.124 4 ET0IA -12.056( P= 90%) .

In order to explore the effects of de-electronic water on the growth of tomato grown in greenhouse,＇maofen 802＇was selected as experimental material to analyze the effect of different de-electronic water irrigation volume on yield,quality and water use efficiency. The results showed that de-electronic water could obviously promote the growth of tomato grown in greenhouse and improve water use efficiency. Compared with normal water ( CK) ,the Pn,Gs,Ci,Tr,yield per plant,Vc content,sugar-acid ratio,lycopene content and water use efficiency of tomato grown in greenhouse with the same irrigation amount of de-electronic water ( T2) were significantly improved by 9.56%, 14.29%,4.75%,7.52%,11.82%,13.28%,7.80%,6.76%,and 7.96%,respectively,but the titrated acid content was significantly reduced by 5. 88% ( P＜ 0. 05) . Comprehensively considering yield,quality and water use efficiency of tomato grown in greenhouse,the recommend irrigation amount of de-electronic water was 3 120 m3 /hm2 .

The influence of different laying slope,working pressure and laying length on the irrigation uniformity of inlay patch drip irrigation tape was studied by adopting uniform orthogonal design and fitting the prediction model of irrigation uniformity. The results showed that working pressure and laying length had significant influence on the irrigation uniformity of drip irrigation belt,while laying slope had no significant influence on it. The ranking of the three factors was as follows: working pressure ＞ laying length ＞ laying slope. As the laying length increases,the irrigation uniformity of the drip irrigation zone decreases. Therefore,in order to ensure the irrigation uniformity,the laying length should be reduced as far as possible. Under moderate working pressure,the irrigation uniformity of drip irrigation zone is higher.

The water resources and agricultural management of Colorado River Basin in the United States is a typical example of America and the world. The river characteristics and water resources situation are similar to the Yellow River Basin in China. Based on the data of water resources,climate,economy,and demography of seven western states in the United States in 2005 and 2010,this paper establishes a multiple linear regression model to analyze the factors affecting farmers＇ income,such as water resources utilization,weather and climate, etc. The results indicate that farm income is significantly affected by the proportion of surface water irrigation,crop planting income,average precipitation during crop growing period,maximum average temperature and minimum average temperature. When the proportion of surface water irrigation is increased by 1%,the net income of farmers will decreases by about 54.19 yuan. When the proportion of crop planting income in the total income of agricultural products trading is 41.34%,the net income of farmers is the lowest. When the average rainfall in the region is more than 42.37 mm,farmers＇ income will increase 399.97 yuan for every 1 mm increase in rainfall. Therefore,farmers＇ income can be increased by comprehensively utilizing the irrigation mode combining diversion river irrigation and water storage irrigation,improving irrigation technology,optimizing planting structure,and actively guiding farmers to actively respond to the impact of precipitation and temperature rise.

In order to analyze the relationship between soil air permeability and saturated water conductivity characteristics,the single ring infiltration method and the three-dimensional steady state soil permeability measurement method were used to measure the saturated water conductivity and air permeability of brown soil in Tai＇an city. The influence of the different diameter infiltration rings on the saturated water conductivity was studied,and the relationship model between the air permeability and saturated water conductivity was established. The results showed that the infiltration rate and cumulative infiltration amount decrease gradually with the increase of the diameter of infiltration ring,the infiltration rate and the cumulative infiltration amount was the largest with a diameter of 10 cm,followed by 20 cm,and the smallest with a diameter of 30 cm. Meanwhile,the significant differences were found in the values of saturated water conductivity with different infiltration ring diameters. Then,the relationship between gas conductivity and saturated water conductivity was discussed by using saturated water conductivity model and gas conductivity model. Through the logarithmic relation curve of saturated water conductivity and gas conductivity,it could be found that there was a significant logarithmic relation between air permeability and saturated water conductivity,and the R2 of the fitting relation curve was up to 0.874 1,indicating that it was feasible to estimate the saturated water conductivity of brown soil in Tai＇an city.

According to the situation of relatively developed water-saving in engineering and agronomy in China,but still low utilization efficiency of water resources,the field of water-saving in agricultural management has become the current focus of attention. The evolution path and hot spots of research on water saving in agricultural management were analyzed by using data from 2000 to 2019 from CNKI and CiteSpace mapping software. The results show that the annual publication volume of this field is fluctuating,the number of core papers ( Peking University core journals,CSSCI and CSCD journals) is in a stable state,and the research content is deepening constantly,which is closely connected with the guidance documents of national departments. Agricultural management water conservation is a research field centering on water rights allocation,in which water rights trading is the core of the current path. In the context of the strictest water resource management and land transfer,the compensation for water saving and the replacement of agricultural water rights in the resource-deficient areas are the forefront research hotspots in this field.

In order to clarify the characteristics of N2O emission from vineyard soil under different nitrogen application rates,and to provide scientific basis for guiding vineyard rational nitrogen application and formulating greenhouse gas emission reduction measures,taking the Guanzhong semi-humid zone vineyard ecological system as the research object,under the integration of drip irrigation and fertilization way, three nitrogen treatments were set,including N0 ( no nitrogen application) ,N155 ( 155 kg /hm2,which is 2 /3 of the traditional nitrogen application rate) ,and N232 ( 232 kg /hm2 ) ,the traditional nitrogen application rate. The static chamber-gas chromatography method was applied to monitor the annual N2O emission flux of the vineyard ecosystem in the semi-humid region of Guanzhong plain,China. ( from September,2018 to October,2019) . The characteristics of N2O emissions from vineyard soils with different nitrogen application rates and their response to soil environmental factors under drip irrigation water and fertilizer integration models were discussed. The results showed that nitrogen application significantly increased the N2O emission flux ( p＜0.01) ,the cumulative N2O emissions under N232 treatment were 2.26 and 1.31 times of N155 and N0 treatment,respectively. The cumulative N2O emissions from N0,N155,and N232 treatments during the grape growing period accounted for 61. 91%,54. 13%,and 68. 18% of the annual emissions,respectively. Under nitrogen application conditions,the N2O emissions during the grape coloring period accounted for 37.00% and 45.75% during the growing period,respectively. N2O emission flux was significantly positively correlated with soil temperature and humidity ( p ＜0.01) . N2O emission from N0 treatment was mainly affected by ground temperature. was the main controlling factor affecting N2O emissions under N155 and N232 treatments. The grape growing periods were the main periods of N2O emissions. Strengthening the application management of nitrogen fertilizer during the grape growing period,especially the coloring period,is an effective way to reduce N2O emissions from vineyards in the semi-humid region of Guanzhong plain,China.

In order to explore the effect of different drip irrigation methods and water and fertilizer combinations on the growth,photosynthesis and yield of grape under the gravel soil conditions in the eastern foot of Helan Mountain,the orthogonal experiment of three factors and three levels was adopted,and the range analysis and variance analysis were used to obtain the order,significance,influence trend and optimal combination of the three factors. The results showed that the order of the three factors on yield was: drip irrigation mode ＞ irrigation quota ＞ fertilizer amount,all of which reached a significant level. According to the effects of drip irrigation,irrigation quota and Fertilization on the growth,photosynthesis and yield of wine grape,the optimal level combination of the three factors was determined as follows: drip irrigation under film,irrigation quota 2 295 m3 /hm2,fertilization 291.45 kg /hm2,the highest yield of grape was 10 507.59 kg /hm2,which was 169. 63% higher than CK( no film drip irrigation,irrigation quota 1 395 m3 /hm2,fertilization 174.75 kg /hm2 ) .

In order to study the multi-objective optimization model of irrigation system for crops in inland arid areas under the condition of inadequate irrigation,in this study,the cotton in the Awati harvest irrigation area in Xinjiang was taken as an example,the farmland water balance model was used to simulate the relationship between the cotton root layer water amounts,the relative yield of cotton was calculated by using the crop water production function model,the irrigation time and irrigation quota of cotton were taken as independent variables,and the relative yield and total irrigation amount during the whole growth period were taken as objective functions to establish a multi -objective optimization model of crop irrigation system in inland arid areas. Aiming at the multi-objective constraint problem,the CNSGA-Ⅱ algorithm was used to solve the optimization model. The calculation results show that the growth of crops in inland arid areas mainly depends on irrigation,and rainfall has little effect on their relative yield. Compared with the previous irrigation system,the irrigation system optimized in average water level year can increase the relative crop yield by 2.5% to 3.1% when the irrigation quota is consistent. At the same relative yield,irrigation water can be saved 495 ～ 705m per hectare of land. The optimization of the cotton irrigation system shows that the model established in this paper can be applied to the optimization of the irrigation system of other crops in arid areas and has certain reference significance.

Accurate mastery of soil moisture dynamic changes is crucial for accurate formulation of irrigation plans. In this study,according to the data of soil water and 7 meteorological elements ( temperature,rainfall,evaporation of water surface,sunshine hours,wind speed, absolute humidity and ground temperature ) of the same period from 2018 to 2019 by the evapotranspiration apparatus of Wudaogou experimental Station,the BP neural network method was used to establish soil moisture prediction model of different layers ( 10,30,50 cm) in winter wheat growth period. The models were BP ( 7-9-1) ,BP ( 7-12-1) and BP ( 7-14-1) . And the genetic algorithm was used to optimize the BP neural network model. The results showed that both models could be used to predict soil moisture during the growth period of winter wheat,among which the BP neural network optimized by genetic algorithm could better improve the prediction accuracy,and the prediction accuracy increased with the increase of soil thickness. The average relative errors of BP neural network for soil moisture prediction in 10,30 and 50 cm soil layers were 6.2%,4.0% and 2.9%,respectively. The mean relative errors of soil moisture prediction in 10,30 and 50 cm soil layers by genetic BP neural network were 3.8%,1.7% and 1.3%.

The surface water source must go through the desilting and filtering system to ensure that the irrigation water can pass through the drip irrigation system smoothly. The desilting basin needs to undertake the first precipitation task. Aiming at the shortcomings of traditional linear desilting basin,such as low sedimentation efficiency and large occupied area,according to the law of water and sediment movement, the desilting basin was improved by adding opening flow regulating teeth in the drainage section and designing serrated spillway trough in the overflow weir,so as to improve the sediment settling efficiency on the premise of reducing the occupied area of desilting basin. By building the physical model,the water depth,velocity,sediment concentration and particle size were monitored and analyzed. The results show that the improved linear desilting basin with the design of the opening flow regulating teeth and the increase of the spillway trough can effectively reduce the water head and the flow rate and stabilize the water level in the basin,thereby improving the sediment settling efficiency. The flow regulating teeth and spillway trough respectively reduce the flow rate by 25.45% and 42.82%. Compared with the traditional linear desilting basin,the design of the flow regulating teeth improves the sedimentation rate by 9.42%. The maximum sediment settling rate is 72.08% when the channel length is 5 m,and the minimum outlet sediment content is only 0.212 kg /m3 . When the inlet sediment concentration is 1 kg /m3, the overall sediment settling efficiency is increased by 34.39%,and more than 65% of the sediment grain size of the outlet tank is less than 0.05 mm. It fully shows that the sand settling effect of the improved linear desilting basin is remarkable. The research results determine the optimal structure scheme of the improved linear desilting basin under constant velocity.

The development and utilization of salt wasteland provides an important way to solve the conflict between social and agricultural development. Soil salt content is an important index that affects crop growth and yield. In order to study the temporal and spatial distribution characteristics of soil salinity in salt wasteland cotton field under long-term drip irrigation and its influence on cotton yield,through field monitoring data,the temporal and spatial variation of soil salinity in the two year after mulched drip irrigation was studied,and the relative desalination rate,seedling emergence rate and yield were compared and analyzed after 8 years of drip irrigation under membrane. The results show that: after 8 years,the average desalination rate of soil of the 6th company of the 121th corp was -84.89%,the average desalination rate of soil of the 14th company of the 142th corp was -34.81%,and the average desalination rate of the 9th company of the 149th corp is - 69.84%; the emergence rate increased from at least 21.7% in 2008 to a maximum of 74.7%; the yield increased from a minimum of 261 kg / hm2 in 2008 to a maximum of 6 390 kg /hm2 ; Long-term submembrane drip irrigation reduced soil salt content and increased soil desalination rate,seedling emergence rate and cotton yield.

In order to explore the response of N2O emissions from controlled irrigation paddy fields to the application of bio-organic fertilizer, the N2O emission fluxes from paddy fields with different fertilization systems were observed in-situ through field experiment. A total of 3 fertilization treatments were set up in the experiment,including full chemical fertilizer ( CK) ,50% chemical fertilizer +50% bio-organic fertilizer ( T1) ,full bio-organic fertilizer ( T2) .The research results showed that the addition of bio-organic fertilizer could significantly reduce N2O emissions from paddy fields. The cumulative N2O emissions of T1 during the whole growth period of rice were reduced by 35.96% compared with CK ( p＜0.05) . The cumulative N2O emissions of T2 were 89.11% and 83.00% lower than those of CK and T1 respectively, and the differences between T2 and the other two treatments ( CK and T1) were significant ( p＜ 0.05) .The cumulative N2O emissions at various growth stages of rice were the lowest in T2 treatment,and significant differences were observed between T2 and the other two treatments ( p＜ 0.05) . From the first dehydration of the soil to the maturity of rice,the N2O emission fluxes in all treatments showed a significant or extremely significant positive correlation with Water Filled Pore Space( WFPS) . Therefore,the reasonable application of bio- organic fertilizer and chemical fertilizer can effectively reduce the N2O emissions from paddy fields,and the research may provide a theoretical basis for the formulation of greenhouse gas emission reduction measures in paddy fields and the sustainable development of agricultural ecological environment.

The transferability of agricultural water rights to ecological water rights is conducive to the inclusion of ecological water rights in the basin water distribution plan of Tarim river oasis,to ensure the distribution of ecological water rights of oasis,and to promote the maintenance and restoration of oasis ecological environment. Therefore,in this paper,the connotation of ecological water right allocation adjustment based on transferable agricultural water right allocation in Tarim river basin was theoretically defined,the content,method and model of adjustment were determined,and the adjustment of oasis ecological water right allocation was calculated. The results are as follow: ① The adjustment of oasis ecological water rights based on the allocation of transferable Agricultural water rights is mainly occurred in the source of Tarim river basin; the adjustment of oasis ecological water rights is needed only in the stem of Tarim river basin; Yerqianghe river basin has the highest adjustment of oasis ecological water rights; and in the middle and low reach of mainstream of basin,the allocation of ecological water rights isn＇t needed. ② Compared with the oasis ecological water rights allocation that has been studied,the oasis ecological water rights allocation adjustment based on the transferable agricultural water rights allocation in Tarim river Basin can reduce the oasis ecological water rights allocation in the basin water allocation scheme and improve the ecological water rights guarantee ability. ③ In Tarim river,the adjustment and reduction of the ecological water rights were greater than that of the minimum oasis and the restoration of the appropriate oasis,and the adjustment and reduction of the maintenance and restoration of the minimum oasis were greater than that of the maintenance and restoration of the appropriate oasis. ④ The reduction proportion of the allocation of oasis ecological water rights in the mainstream of basin is higher than that in the source in Tarim river basin. Moreover,the decrease proportion of the allocation of adjustment of oases ecological water right in 2030 is higher than that in 2020,and that in in 2015 is the smallest. This will become a reference to determine the allocation scheme of oases ecological water rights in Tarim river basin.

In order to improve the monitoring accuracy of satellite remote sensing on soil salinization,GF-1 satellite remote sensing and Unmanned Aerial Vehicle multi-spectral remote sensing were used to obtain remote sensing image data in mid-June 2018 and simultaneously collect 0 ～ 20,20 ～ 40 cm in -depth soil salinity data. Through analysis,the principle of Lorentz curve was used to characterize soil heterogeneity. The BP neural network,support vector machine and extreme learning machine were introduced to construct soil salinization monitoring model. The resampling scale conversion method was used to scale up the UAV data,and the GF-1 satellite data was corrected with the scaled up UAV data. Then inversion modeling was carried out and compared with the model established by directly using satellite data. The results showed that the heterogeneity of the experimental area was positively correlated with the coefficient of variation. The accuracy of the machine learning algorithm model constructed by drone data was higher than that of satellite data. Among them,the optimal model for inversion of soil salt content from UAV remote sensing data at a depth of 20 cm was the SVM model,R2 was 0.875,RMSE was 0.132,and RPD was 2.773; the optimal model for inverting soil salinity from UAV remote sensing data at a depth of 40 cm was BP model,R2 was 0.709,RMSE was 0.144,and RPD was 1.781; the optimal model for retrieving soil salt content from GF-1 satellite remote sensing data at a depth of 20 cm was the SVM model,R2 was 0.453,RMSE was 0.245,and RPD was 0.055; the optimal model for inversion of soil salinity from GF-1 satellite remote sensing data at a depth of 40 cm was BP model,R2 was 0.271,RMSE was 0.267,and RPD was 0.001. Through upscaling,the accuracy of the model of soil salinity inversion from satellite remote sensing can be improved. The R2 can be increased by 0.4 to 0.5,the RMSE can be reduced by 0.061,and the RPD can be increased by 1.308. This study can provide a reference for improving the method of monitoring soil salinization by satellite remote sensing.

The proportion of agricultural water consumption in China is 61.4%. Water measurement is one of the most basic and critical work in agricultural irrigation. How to ensure the accurate measurement of irrigation water consumption is the premise to support the development of agricultural water conservation and promote the reform of water price. Taking the U-shaped channel commonly used in agricultural irrigation as an example,this paper analyzes the application of Bashir and parabolic flume. The VOF model of FLOW-3D software is used to simulate the flow field in the Parshall flume and parabola flume. The velocity distribution and turbulent energy dissipation rate of each part of the two flumes are analyzed,and the total head loss curves of the two flumes are obtained. The analysis results show that the head loss of the Bashir flume is larger when it is used in the U-shaped channel,while the head loss of the parabolic flume is only 30% of that of the Bashir flume, which is very suitable for measuring water in the U-shaped channel. This study can provide references for the arrangement of water measuring facilities in irrigation area.

In order to calculate the uniformity of combined sprinkler irrigation quickly and simply,based on the test data of single sprinkler and according to the principle of water volume superposition,the calculation method and steps of the combined sprinkler irrigation uniformity calculated by ArcGIS system software were studied. The calculation results of different interpolation methods and the size of interpolation grid were analyzed and compared through calculation examples. The research showed that the PAEE,RMSE and MSE values of the natural neighborhood interpolation method were 0.093,0.048 and 0.261 respectively,which were the smallest among the four interpolation methods studied. Under the same layout form and the same sprinkle spacing,the influence of 0.4,1.0 and 1.5 interpolation grid sizes ( resolution) on the calculated results of sprinkler irrigation uniformity was compared,and the results showed that the differences were not significant. By comparing the calculation results of ArcGIS system software,self-compiled software and Surfer software,it was found that the difference between the calculation results of various methods was no more than 2.9%. Taking triangle layout sprinkler irrigation system as an example and taking triangle area and the area between two branch pipes as typical areas respectively,the combined sprinkler uniformity ( Cu) was calculated with ArcGIS system software,it was found that the difference between them was 0.8%. The results show that it is feasible to calculate the uniformity of sprinkler irrigation by using ArcGIS system software,and the operation is intuitive,fast and simple.