Calibration Of CERES-Maize Model And Analysis Of Water Saving Potential In Arid Area Of Northwest China

Crop model DSSAT provides an effective tool for crop growth simulation. The results of model calibration and validation provide a theoretical basis for the extension of simulation results. The article which based on Yingke irrigation area of oasis in the middle reaches of Heihe River, constructing DSSAT model by collecting experimental data and graphic data from different branch canal irrigation. Then it depends on the maize phenology, crop biomass and maximum leaf area index to test the DSSAT model. By using the maize growth data in 2012 at Yingke irrigation area, the CERES-Maize model crop varieties were calibrated and the maize growth data in 2013 were used for validation. The outputs of these branches were estimated on the basis of above research, then maize outputs irrigation amount, cultivated land area and the number of employed persons were treated as analytical factors, DEA would analyze the efficiency of water use and allocation of other resources. According to the research contents and ideas, the main results are as follows:1.Make each experiment area as a unit, build the crop growth model of Yingke irrigation area which is based on constructed meteorology module, module of soil, irrigation and fertilization etc. module.2.The study is based on the experiment of maize in 2012,2013 at Yingke irrigation area. The DSSAT model is used to simulate the growth period, LAI, yield and aboveground biomass of maize. The changes in different years help to get the main parameter and value which influences the crop growth model. Some conclusions can received by analysis the model, the error of simulation on maize growth period was only 3-days,while the RE and nRMSE of yield and aboveground biomass of maize were also less than 10%.Although there is larger relative error on the simulation of LAI, the result could be accepted.3. According to the maize experiment in 2012 at Yingke irrigation area and the different soil type distribution, estimate output of 11 maize branch area.4. Based on the data envelopment analysis, put the irrigation water amount, the crop planting area, the number of employees as input factors, output of maize as the output factor to calculate. There are 5 branches get the irrigation water effective in DEA. the remaining seven branch did not reach the efficiency value of 1, but the overall get a high average to 0.93. Water analysis results show that under existing technical conditions and keep the crop output the same, the 11 branches at Yingke irrigation area can save 4.29 million m3 water, which take 5.0% of the whole irrigation. The optimum water content of 11 branches is 80.7 million m3. In addition, it could save 4.8% of the land resources and 5.8% of the human resources.