Research On Optimized Irrigation Program Of The Artificial Grassland In The West Of Jilin Province

The water resource is the material foundation of all the mankind society, production and living. Have no water resources to have no mankind. With the progress of mankind, the world economic development and the extension of city-turning, the demand of water are getting more and more, water deficiency has become a popular problem in the modern world. Only the agriculture irrigation accounts for about 70 percent of the general water resources. Our country's territory is broad, and the water resource is distributing very asymmetry everywhere. The water amount of resources of the southwest region has 39% of the national total amount or so, but the water resources of northwest, north China, and northeast three greatest areas have 17%.For this, some measures, such as developing the saving water irrigation, and exploiting the water resources in rational way, have been taken to keep the sustainable development of agriculture, industry and environment.At present, our country traditional water-saving irrigation mainly launches on the stages of acquiring headwaters, transportation and sprayed irrigate, and has actually attained the purpose of saving water and heightening the utilization of irrigation water availably. However, along with the growth of the industry, agriculture, economy and the population, the demand of the water resource increases increasingly, and most people think on the thought that saving water is equal to output reduction etc. reason, so the above-mentioned water-saving irrigational techniques which are used in common in our country didn't obtain real results currently, didn't alleviate the nervous problem of water resources by the root, and didn't make the one who use water set up the water-saving consciousness. Under this kind of background, the research puts forward the new water-saving irrigational theories, namely: the basic target of the water-saving irrigation is under the situation that the limited water measure, acquiring the irrigation production value of unit water quantity with minimum expenses and maximum limit (or yield), the theories of not- full irrigation emerges with the tide of the times.Not- full irrigation, which is also called limited irrigation or lacking irrigation, lies in carrying on the active artificial managements of lacking water and establishing excellent irrigational system according to the physiological characteristic of the farm crop and the regulation of water-needing. Opposite in traditional irrigational theories, not-full irrigation is the reform of irrigates idea. The main target of the full irrigation is to acquire farm crop of high and steady produce, and to promise that the traditional irrigational request that the watering all satisfy"in time and capacity"each time will be satisfied under the limited condition of controlling soil degree of humidity . Not- full irrigation is put forward aiming at the lacking of water resource and the catholicity of lowly water-using efficiency. Its theories bases on: The farm crop teach a stage to be subjected to a drought and watering appropriately in the some whole life, strengthen the ability of farm crop itself to permeate the ability of regulate, and can be in the Photo-synthesis , nourishment growth , material conveyance and yield formation etc. physiological process to produce a compensate mechanism effectively to realize the efficiency of the using of limited humidity. Combining concrete environment of the agriculture production, and the objective regulation of the farm crop growth to adjust irrigation, studying the inside physiology of the farm crop-humidity relation, and making extensive adoption and expansion of not-full irrigate mode, not-full irrigation will take an important role in society, ecosystem and economic.This text discusses various mathematics models of not-full irrigate experiment, and provides the definition and solution to these models of the parameter. Aiming at the growing characteristics of farm crop in Jilin western region, the clover's growing stages are divided in to return-green, cent, bud, bloom, mature five stages. This text sets up mathematics model by adopting Jensen model to be the function of humidity's production and carries on related of not-full irrigating test. The result of the test indicts, the key periods of clover's water-needing in Jilin western region are cent, bud and bloom periods. According to the result of increased production by irrigating in each growth stage of clover, the opposite growth rate of the bud-period is the tallest. However, the cent stage is the most obvious about the influence of the water shortage upon the yield. Therefore, under the situation that supplied water is shortage, we should satisfy the needing of water of cent and bud first.All the text encircles water-saving and water-installing efficiently, applies systems analysis, operational research, mathematical statistics and the principle of water-saving irrigation and builds up dynamic programming of clover's water-saving irrigation. The text provides the solving process in details to the dynamic programming. Depending on the clover's needing regulation, this test applies dynamic state programming theories and not-full irrigating principle, refers to the parameter data of the area clover not-full irrigation, and provides the optimum collocation of the water measure under different irrigation requirement for the purpose of reducing the quantity of irrigational water and avoiding the waste of water.According to the simulation of the model's result, we have got the scheme of optimum water distribution and the water supply quantity for plentiful produce of clover in the test-area. That model can be accurate to really settle key period of the water for the crop's need, guide people to infuse"the key water", and guide how to admeasure water quantity on time under different water shortage degree in order to make opposite yield of farm crop biggest. It will certainly be irrigated under the quota for every irrigated area in future, the amount of water irrigated offers reference in optimum distribution and planning and design of the irrigated area at every stage. Under not-full irrigational condition, there are lots of sublimate conditions which have been used all over the whole establishment of this model, assuming that in this model the soil moisture change is zero and the earth's surface path flow and the amount of underground leakage caused by excessive irrigation is ideally turned to zero. According to above two assumption conditions, the actual transpiration is predigested to the sum of effective rainfall and the amount of irrigation water based on the balanced equation of water yield of field. Water of income is it optimize model can offer the basis for the fact that the agricultural water in the area lacking of water is managed to manage, have certain reference value in the similar area of the North. If the area in which the regional water resource situation changes, must do corresponding modification on the model which is used to distribute irrigation water best, and it is need to await further developmental research.