Research On Assembling The Saving Water Technique And Synthetically Optimum Of Well Irrigation For Rice In The Course Of Field Produce Of San Jiang Plain

The Thesis is the sub-project of the task named he Agricultural Synthetically Development Study on Low-Wet Land of San Jiang Plain?which belongs to he Ninth Five Years Plan of China? Through researching the system, the writer eater to provide some data and theoretical basis for the saving water model of well irrigation for rice and continued using and development of agriculture and groundwater resources.San Jiang Plain is the most important base of commodity grain of China. The area under cultivation of well irrigation for rice has been expanding year after year of lately year. Groundwater resources has been become the restricted factor. The development of San Jiang Plain has been restricted by groundwater. Ultra-extracting the groundwater and wasting the water resources by artificial t~ctor, the dynamic balance of groundwater has been destroyed.So, more and more pumps can work and the appearance of funnel has been arisen. The water quantity used for agriculture make up 70 percent of the total used water of society. Most of water resources used for agriculture have been used for rice irrigation, it makes up 90 percent of agriculture water. So, we must research the new model of saving water on rice irrigation. We should master the regularity of water motion in field. Thus, we can irrigate in good time, in proper water quantity and temperature. So, the emphasis should be put on how to save water resources, how to raise the water temperature and output.The task research t,n the Well irrigation for rice of San iiang Plain. During the course of filed produce, the writer take sunning water pool, irrigation ditch, field, motor-pumped well and agricultural machinery as a whole system. Through observing the data and applying the method of interrelation and regression analysis, we build up the water balance model that fit for the area of San Jiang Plain. The model includes the model of soil permeability, the model of water surf~ce evaporation and the model of water requirement for rice. We apply the method of season forecast to build up the model of forecasting rainfall. At the same time, we build up the model of forecasting water requirement through the method of time array analysis. Using frequency analysis, we also calculate the designed irrigation quota and designed irrigation system. The writer studied the mechanism of raising temperature insunning water pool and the water depth of pool and the water temperature in pool. We also build up the mathematical function between water temperature in irrigation ditch and air temperature and the speed of water in ditch.The paper researches the distributed regularity of field pool, and the method of the water irrigation. At the same time, tbe writer studied the motor-pumped well and agricultural machinery according to the designed condition. It includes choosing the model of well, the type of pump, the matching power plant, the type and scale of agricultural machinery and the relationship between them. At last, through designing a typical area, the writer compose each technique together, such as technique of engineering saving water, farming technique, field management technique and raising water temperature system and so on. Through studied the system, we can save water resources 20 to 30 percent Thus, the writer calculated the most suitable area of planting well irrigation for rice in San Jiang Plain. The results of the paper provide some theoretical basis for further research.Fu QiangMechanization of Agricultural EngineeringYang Guang Lin...