Computing and Study on Irrigation Requirement in Field of Bojili Irrigation District

The Yellow River Basin is one of the areas of serious water shortage in China. Water-saving irrigation is an important part of the current building and basin of the Yellow River Irrigation water management. In this paper, Shandong Bojili, Irrigation District, for example, of the Yellow River Irrigation crop water requirements and irrigation system, and provide a scientific basis for the improvement of irrigation and watershed management. This article is calculated by the irrigation district observed data various crop water demand, deducing the net irrigation water demand; then through the model to test whether the current crop irrigation system are reasonable, and field irrigation system evaluation, seeking actual field irrigation efficiency; final by the comparison of two different irrigation system program, determine the trial District reasonable crops'irrigation in, represents years of field irrigation water demand and water process line is obtained on this basis. Firstly Irrigation District FAO latest recommended Penman-Monteith method reference evapotranspiration ET ₀ , with KCISA Calculating accordance with the method of calculation of the FAO crop coefficient of the ten kinds of crops the K _{c ; thus calculated on the basis of crop the water demand ET C , according to the results of analysis of the different crop water requirement rules; frequency of calculation of the amount of crop water stress NIR (net irrigation water demand), seeking four representative years of the irrigation district and analysis on behalf of the years during the year of natural moisture status and crop water stress law. Two years of irrigation measured data on ISAREG model determine inspection and parameters, found in good agreement with simulated soil moisture change curve with the measured soil moisture content, shows that the model can be used to simulate or evaluation of local crop irrigation system. Evaluation of the current winter wheat irrigation system simulation results that the existing irrigation system has led to a decline in crop yields more, there is a need to improve and perfect place. Of the the irrigation experiment measured data analysis, to determine irrigation district field soil infiltration parameters K, α, n by field irrigation the simulation model SRFR analog and then integrated to find the of Huimin field irrigation efficiency of 0.68, Wudi 0.52. Area status quo irrigation efficiency, more waste of water, and also that the area especially Wudi water-saving potential is great. To contrast two irrigation systems seek the Irrigation District reasonable crops'irrigation, with ISAREG model simulation, by comparison of the simulation results indicators to determine the recommended four years on behalf of ten kinds of crops to cut a minimum and save water for goals Crop irrigation system. Invert the representative years Huimin and Wudi to push to the field of basic irrigation water demand and water demand process on the basis of simulation and optimization of the irrigation system. As the the decade average water supply and water distribution ratio, average year Huimin adequate water supply and surplus more Wudi water shortage have to seek countermeasures to meet the needs of calculation results visible.}