| In order to explore the arid oasis farmland moisture migration regularity and determine reasonable irrigation quota of cotton under film drip irrigation, Studied Tarim Irrigation area under Film Drip Irrigation Cotton dynamic characteristics of soil moisture and water balance law, analyses the factors that influence the membrane in cotton field with drip irrigation trees between the water evaporation and utilization efficiency of, Analysis the factors influencing membrane in cotton field with drip irrigation trees between the water evaporation and utilization efficiency, established under film drip irrigation cotton field crop coefficient and vapor emission calculation model, obtained under film drip irrigation cotton field actual evapotranspiration quantity, explore the cotton with drip irrigation under plastic film mechanism of water consumption, to reveal the arid area oasis crop water relations, formulate reasonable under film drip irrigation of cotton to provide the basis. The main conclusions are as follows:(1)The variation characteristics of reference crop evapotranspiration in the whole growth period were expounded. The reference crop evapotranspiration(ET0) increased from January to mid July, and reached the maximum in July. After June, with the decrease of the radiation intensity, the temperature decreased,and the ET0 began to decrease. During the cotton growing period, the reference crop evapotranspiration743.19 mm, the average daily value of 4.24mm/d. At the seedling stage ET0 accounted for 31.88% of ET0 in the whole growth period, bud period accounted for 20.4%, flowering boll opening period accounted for33.74%, accounted for 13.98%.(2) Proved the law of water transport in the oasis of arid region. Soil moisture change process is divided into 3 stages, from mid April to mid July for soil moisture stable period; from mid July to the end of 8 for the period of severe soil moisture change; from the end of 8 to the end of 10 for the slow consumption period. From the spatial variation, reduce soil moisture in cotton field mainly occurred in 0 ~60cm.(3) The crop coefficient and the actual water consumption of cotton were determined. Single crop coefficient and dual crop coefficient method to calculate the film drip irrigation cotton evapotranspiration and using the principle of water balance measured evapotranspiration overall trend consistent; overall single crop coefficient to calculate evapotranspiration intensity less than dual crop coefficient to calculate the intensity of the evapotranspiration. |
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