Research On Simulation Of Field Moisture In Irrigation Area Of Arid Inland River

With the development of social economy in xingjiang, more and more water which used in agricultural are demand, with poor water resource and uneven distributionin temporal or spetial, all these problems and lower utilization efficiency seriously restricted the economy development in Xinjiang. So, the high efficiency method must be done to the water resource in irrigation area, strengthening the research on field moisture transformation and consumption in irrigation area.The research base on an example in Fengshou irrigation area of Awati county in Akesu, through the experimentation in the field, to analysis the change of soil water content and moving of under water, which in the condition of current irrigation. In the condition of irrigation, with the character of crop growth and soil moisture change, the aerated soil can be divided into epipelagic layer, lower layer and deep layer. Taking phreatic evaporation as the transducer of ground water furnish out soil moisture, and taking day as the time section to build simulation model of soil moisture in a field, it could simulate the irrigation water distribution in the field and soil moisture changes course. Main research results can be concluded as follows:1) With runoff model and evapotranspiration model of Xin'anjiang model, take day as the time section to describe the irrigation water distribution and soil moisture rising consumption process in the fields. From rising consumption process of the field moisture, the change tendency between the simulated values and the measured values was same, the average of absolute error was 15.1 mm, the maximum was 23.5 mm; And the relative error was 5.8% on average, the maximum was 9.3%; ABS average error of daily moisture process was 0.9%, the discrepancy of moisture content (ΔW) was 0.16, the effect of model simulation is better;2) In the period of growing, soil moisture with infiltration and evapotranspiration changed strongly, which showed short-term fluctuation in the process. Transformation was active between soil water and groundwater: when irrigating, soil moisture was rapidly increasing, after irrigating, it was rapidly fall. From whole irrigation, the largest increment of soil water was about 50mm (about 30% of the volume of irrigation). The soil water content with the vertical infiltration and evapotranspiration dissipated fast, on the 1st day after irrigation dissipated soil moisture storage capacity increased about 40%, showing the storage capacity of the soil is clearly inadequate;3) In the arid inland river irrigation, the crop growths mainly depend on irrigation, and the precipitation can be ignored. According to the analysis of experimental data, in addition to the irrigation of soil moisture had a great impact, and precipitation of soil moisture also had a great impact. How much precipitation will have an impact on soil moisturehas yet to be studied and confirmed.