Study On The Law Of Soil Water And Salt Transport And Crop Growth In The Field Of Automatic Drip Irrigation

With the continuous development of science and technology,intelligence and information technology continue to spread.The development of automatic irrigation technology has become an inevitable trend in the development of modern agriculture.Therefore,the response of farmland irrigation indexes,such as soil water and salt transport,farmland microclimate and crop physiological growth,to the high-efficiency water-saving irrigation technology needs further research in order to better apply the high-efficiency water-saving technology to the field.Therefore,through the field tracking test of traditional film top irrigation technology(T1),general film bottom drip irrigation technology(T2)and automatic film bottom drip irrigation technology(T3),Nongfeng 133 cotton was selected as the research object to analyze the law of water and salt transport of cotton,the impact of crop physiological growth indicators,farmland microclimate indicators and the impact of yield;at the same time,combined with the field investigation and sampling data of the 148 regiment of the eighth division,this paper analyzed These indicators are combined with 26 representative evaluation factors such as environment,economy and society to analyze the comprehensive benefits of automatic drip irrigation,find out its main shortcomings and advantages,and provide theoretical basis for future improvement and better promotion,and draw the following conclusions:(1)From the analysis of soil water and salt environment: the overall water content of film irrigation is the highest,and the leaching effect of soil salt is better.T3 had the same law of soil water and salt transport as T2,but its soil water content was higher than T2,and the effect of salt leaching was better than T2.The spatial movement of water and salt in T2 and T3 soil before and after irrigation also showed that the water in the center of the dripper diffused to the surrounding,and a salt crust with the dripper as the center would be formed in the root layer.After that,the salt branch moved horizontally towards the membrane.The average desalination rate of T1,T2 and T3 was 57.1%,10.45% and 14.95%.The salt and water content of each treatment showed opposite change law in horizontal and vertical directions,which fully reflected the characteristics of soil water and salt change of "salt moves with water,water goes and salt stays".(2)According to the microclimate analysis of cotton growing field,the air temperature of T1 treatment was significantly higher than that of T2 treatment(P < 0.05).T2 was significantly higher than T3(P < 0.05).With the development of the growth period,the air temperature is higher in the middle and lower on both sides,which is reflected in bud stage,seedling stage,boll stage and boll stage.The relative humidity showed the rule of T3 > T2 > T1(P < 0.05).With the development of growth period,the relative humidity also increased.The change trend of the ground temperature of each treatment is the same as that of the same day.The upper layer(5-15cm)is greatly affected by the air temperature.T1 is affected by the film damage and vegetation coverage,and the daily fluctuation range of the ground temperature is larger than that of other treatments.(3)From the analysis of physiological growth characteristics of cotton: the four photosynthetic indexes of automatic drip irrigation under mulch were significantly better than the other two treatments.According to the heat map and the comprehensive analysis of each index,it can be concluded that the automatic drip irrigation under the film can provide a relatively good field microclimate environment for crop growth and the physiological growth condition of the crop is the best.(4)Through the fitting analysis of crop growth and development,farmland microclimate index and yield under different irrigation modes,it is found that except air temperature,other indexes have a positive correlation with yield,and the relative humidity,plant height,leaf area and yield have a certain degree of fitting,R2 are 0.8661,0.8585 and 0.8371 respectively;the yield of automatic under film drip irrigation is higher than that of under film drip irrigation and above film drip irrigation respectively 5.8% and 73.2%respectively.(5)Comprehensive benefit results: through the evaluation results of the evaluation index system,the automatic drip irrigation under the film is the best irrigation technology.Compared with film irrigation,its irrigation water utilization coefficient is increased by 38.7%,especially 62.3% manpower is saved.(6)Through the evaluation results,it is found that although the investment cost per unit area of automation is higher than that of conventional drip irrigation,the comprehensive consideration of its control area is large,which greatly saves manpower,and the information technology conforms to the development trend of modern agriculture,so the technology has great application potential in Xinjiang.At the same time,it is necessary to digest foreign advanced technology to reduce costs,to improve the soil environment by appropriate stubble irrigation,to solve the problem of residual film pollution,and to organize farmers' training and publicity.