Nong Bashi Development Of Water-saving Irrigation Mode And Single Well Drip Irrigation Optimization Study

Owing to special geographical position and climate condition, the extinct hungriness-oasis agriculture is formed in Shihezi reclamation area which locates in arid areas of Xinjiang production and construction corps. The environmental characteristic of oasis-drought, surrounded by desert, makes agricultural ecology very fragile and farm field and meadow in a ecological deterioration situation of desertization, salinization and de- generation. In order to bring desertization ,safinization and degeneration under permanent control , it is necessary to lower ground water level and to decrease salt accumulation in tillage layer. The implement of high wa- ter-saving irrigation can lower ground water level and decrease secondary salinization, moreover, can save water and increase field area, as insure the virtuous development of agricultural ecology. The research on drip ir- rigation under sheet-film carried out in 1996 by the eighth agricultural division in reclamation area and the technique is extended. At present the total field area which is irrigated by this technique access to 10,000 ha in Xinjiang Autonomous region, and the technique will be extended inten- sively within a few year. Drip irrigation under sheet-film is applied on cotton and tomato in great area for first time, so it is very urgent to study this technique suitable, irrigation scheduling and design method for ex- tending and applying. Coupling the technical properties of drip irrigation under sheet-film, the present situation of soil-water source, social economic and irrigation technique in the eighth agricultural division reclamation area angl the re- search result of irrigation scheduling, drip irrigation technique and pro- gramming and designing, following research are worked out in this paper: the development pattern of water-saving irrigation for the eight agricul- tural division of Xingjiang production and construction crops; the irriga- tion scheduling of drip irrigation under sheet-film for field crops under the condition of limited irrigation for single well; and the optimum design 55 of drip irrigation under sheet-film system one well. The development pattern of water-saving irrigation for the eighth agricultural division, the irrigation scheduling of drip irrigation under sheet-film and optimum method for pipe net are decided in this paper and draw up software is compiled with Visual Basic 5.0. The research results of this paper provide a practical choose method of water-saving irrigation pattern for policy- maker, and provide irrigation scheduling and pipe net optimum design for drip irrigation under sheet-film system under the condition of single well for designer, and can guide the extending and applying of drip irrigation under sheet-film in reclamation area and Xinjiang Autonomous region. Firstly, every water-saving irrigation method is judged and chose with indistinct comprehensive judging in this paper; Based on above re- sults, this paper draw a conclusion that water-saving irrigation develop- ment pattern in the eighth agricultural division should coupling drip irri- gation under sheet-film and improved surface irrigation presently, and the water-saving irrigation development pattern should be drip irrigation un- der sheet-film and low-pressure pipe-line in the future. Moreover, the op- timum model of irrigation scheduling is worked out in this paper with the method of dynamic programming and enumerate, according to the prop- erty of drip irrigation un...