Research On Real-time Irrigation Forecast And Water Use Plan In Irrigation Area

In China,the management level and water use efficiency of irrigation area are generally low,water resources waste and lack exist at the same time,most irrigation equipment is not advanced enough,and the full-automatic management mode is difficult to achieve in China.In view of the above situation,the research on the real-time irrigation forecast and water use plan of the irrigation area can accurately guide the irrigation time and irrigation quota,and reasonably arrange the water distribution of the canal system,which is of great significance to improve the management level of the irrigation area,the utilization efficiency of water resources and the overall benefit of the irrigation area.The research combined theoretical analysis,model construction,programming and simulation.On the basis of theoretical analysis of the research methods of real-time irrigation forecast and water use plan in domestic irrigation areas,the prediction and calculation correction methods of each parameter in the water balance equation applicable to dry crops and paddy were studied and analyzed,and the common methods in domestic irrigation districts were summarized.The general real-time irrigation prediction model,the optimization model of canal system water distribution and the modification idea were established.The typical canal system of Fengjiashan irrigation area was simulated and applied,and the irrigation water plan of the canal system was preliminarily worked out.The main results and application results are as follows:1?In view of the fact that the daily soil moisture content is difficult to obtain,the requirements for irrigation equipment are high,and there is no study on the correction of no measured moisture content.According to the theoretical analysis,this study summarized the methods applicable to general irrigation areas,established the real-time irrigation prediction model based on the water balance equation according to the two different purposes of prediction and calculation correction,compiled and run the real-time irrigation prediction calculation program,which can achieve the short-term real-time irrigation prediction and timely correction when there is no measured water content.2?Considering the flexibility and accuracy of the model,a general two-stage channel water distribution model was established based on the current situation of the general channel system in the domestic irrigation area,which aims at the shortest total water distribution time and the smallest water distribution time difference between irrigationgroups in each round.Based on the principle of meeting the needs of water users and centralized irrigation,the time difference between planned irrigation day and water demand day is combined with the real-time irrigation forecast and the irrigation time is unified for correction,which is more convenient for irrigation area management.3?The simulation application of real-time irrigation forecast and preliminary preparation of water use plan for autumn crops in typical irrigation area was carried out.The practice simulation shows that the irrigation forecast model and preliminary preparation of water use plan established in this study are more reasonable in practical application,the arrangement of water distribution sequence is reasonable,the water demand is accurate,and it is convenient for unified control.The theory is basically feasible.