Study On The Water And Salt Transport Of Drip Irrigation Of Different Salinity Cotton Fields In Baotouhu Farm

Due to the shortage of water resources and soil secondary salinization has seriously restricted the development of agriculture in Xinjiang. To this end, drip irrigation as a new type of water saving and salt control method, has been widely used in the whole territory of Xinjiang. In this paper, take low, medium and high salinity of three kinds of cotton soil as the research object, analysis the law of the soil water and salt transport of the whole growth period, the optimized irrigation system and to provide the basis for the further development of under film drip irrigation cotton field of sustainable development and water saving irrigation technology.The main research results of this paper are as follows:(1)The change of the groundwater in different salinity cotton field: The higher the groundwater level,the higher the salt content.The overall change trend: The groundwater level rises and the groundwater conductivity decreases during the spring irrigation. The groundwater level decreases and the groundwater conductivity rise slowly during the growth period..(2)Through the observation of the growing period, the change of soil water content and salt content in soil of the low, medium and high salinity of three kinds of cotton soil in growing period are: The water content decreases, and the salt content increases from the sowing time to the seedling stage. The water content increases and the salt content are reduced from the seedling stage to the bud stage. The water content decreases and the salt content decreases and then increases slowly later from the bud stage to the boll opening stage. Under the same conditions,the changes of water content of the high salinity soil is less than the changes in low and medium salinity soil, but the water content is more than the low and medium salinity soil. The changes of salt content of the high salinity soil are more than the changes in low and medium salinity soil.(3)In the cotton growing period, the water content and salt content of every soil layer of the low,medium and high salinity of three kinds of cotton soil are significantly different. Moisture is mainly concentrated in the 50~60cm soil layer. Salt is concentrated in the surface layer and 40-50 cm layer.(4)In the same period of 3 salinity cottons field the water content is emitter > inter-row > film and the salt content is emitter<inter-row<film. Emitter of every salinity cotton field the salinity in the 0-50 cm soil layer is substantially less in September than in April, in the 60-100 cm soil layer is substantially more in September than in April. It shows that the drip irrigation make the soil water move from the emitter to the film and from the surface to the deeper layer. Soil salinity is concentrated in the deep soil layer and the film.(5)Irrigation system for growing period for low, medium and high salinity of three kinds of cotton soil:The irrigation quota of the low salinity cotton in the growth period is 450 m3/hm2, the irrigation frequency is10 times and the irrigation interval is 7 days. The irrigation quota of the medium salinity cotton in the growth period is 450 m3/hm2, the irrigation frequency is10 times and the irrigation interval is 7 days. The irrigation quota of the high salinity cotton in the growth period is 375 m3/hm2, the irrigation frequency is 12 times and the irrigation interval is 5 days.