| In this study, we collected and analyzed the field experiment date, dailymeteorological data, the main soil parameter data, and field management data ofagricultural meteorological test station of Dingxi City in Gansu Province of2010, and thenwe carried a parameter calibration for the Aquacrop model that FAO launched. Using themodel of parameterization, we simulated the canopy cover, the yield, biomass, soil watercontent in2010and2008. On this basis, we evaluated the model and studied the responseof the spring wheat to different moisture conditions in different irrigation methods, basedon the most stable yield and maximize water use efficiency, the best deficit irrigationmanagement strategies are presented. It can refer a water-saving and yield-increasingtechnology when the environment becomes dryer and dryer. The main content of itsresearch and explore include:1. The sensitivity analysis of part non-conservative parameters in Aquacrop modelderived the parameters calibration of canopy growth coefficient, standardized waterproduction efficiency, reference harvest index, building up of harvest index are first andforemost in the model calibration process.2. we can obtained the parameterized Aquacrop model through the trial and errormethod, using the field experiments data of2010and driving the model and taking thebiomass and yield as the objective function. Then we using the parameterized Aquacropmodel simulated and confirmed the canopy cover, yield, biomass and soil water content of2010and2008. The results showed that the canopy cover, yield, biomass and soil watercontent of the spring wheat in2010and2008have a good correlation with the measuredvalues, so theAquaCrop model has good applicability in in semi-arid region.3. The model simulated the yield and biomass of spring wheat under differentirrigation methods in a wet year, a normal year and a dry year: There was so littledifference between full irrigation and deficit irrigation treatment for the yield of the springwheat in wet years, the maximum yield (4.589t/ha) happened with two number ofirrigation frequency(three-leaf stage, grain filling stage)and the maximum biomass (10.608t/ha) happened with full irrigation; The yield and biomass of spring wheat increased withincreasing irrigation water, it can obtained the high yield and biomass (yield:4.663t/ha，biomass：10.824t/ha)with four number and three number (three-leaf stage, jointing stage,heading stage) of irrigation frequency in normal years; The yield and biomass of spring wheat increased with increasing irrigation water and the maximum yield and biomass(yield:4.197t/ha，biomass：9.580t/ha) happened in the full irrigation in drought years.4. Water use efficiency of spring wheat under different irrigation methods:Non-watering treatment had the greatest water use efficiency than once than two times thanthree times than full irrigating, it is thus clear that the more for irrigation water, the lowerfor water use efficiency in wet years; Irrigating once had the greatest water use efficiencythan two times than non-watering treatment than three times than full irrigating, It canobtain higher water use efficiency in the case of filling a water irrigation (T14) at headingstage in normal years; Full irrigating had the greatest water use efficiency than three timesthan twice than once than non-watering treatment, it is thus clear that it can obtain higherwater use efficiency under full irrigation in drought years.5. The optimal deficit irrigation water management was presented based on thehighest water use efficiency and the most stable production in different years: We can getthe most stable yield just to ensure sowing irrigation (50mm) in wet years; We can get themost stable yield to implementation two times irrigation (150mm) on the basis of sowingirrigation in normal years; On the basis of the sowing irrigation we can get the most stableyield to implementation four times irrigation (250mm) in the three-leaf stage, jointingstage, heading stage and grain filling stage in drought years. |
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