Study On Water Efficiency And The Laying Of Drip Tape Under The Condition Of Underground Drip Irrigation Of Alfalfa In The Areas Of Altay

Because of the special geographical position and climate conditions in Xinjiang, the agricultural production ways in most areas is irrigation agriculture mainly. At present, Alfalfa irrigation is surface flooding at most parts of Xinjiang. This irrigation method is easy to waste water resources, but also no help for the growth of alfalfa. Therefore, it will be of great importance to carry out underground drip irrigation on alfalfa, which can improve the yield of alfalfa and irrigation water efficiency.In this paper, taking the typical areas in Fuhai County of Aletai region in the north of Xinjiang as the research background, by studying the conditions of different drip tape arrangements and different irrigation quota,also each index of Alfalfa (plant height, leaf area index in different growth stage, biomass and yield of drip irrigation), reaching the conclusion that the suitable laying of underground drip irrigation tape and irrigation quota for Aletai area in the north of Xinjiang. Analysising the amount of water consumption and water consumption regularity in the suitable conditions. Through field experiments and analysis, this paper comes to the following conclusions:(1)Under the conditions of underground drip irrigation, irrigation drip tape intervals and depth, irrigation quota all have influence on plant height, leaf area index and biomass in each growth period, also on the yield. The influence of irrigation quota and irrigation drip depth is bigger than that of irrigation drip intervals. The treatment of the underground drip interval is80cm, the depth is30cm; the irrigation quota is375mm has the optimal experiment resuls.The amount of dry grass per Mu is513.47Kg, water efficiency is1.17kg/m2, the production cutting rate compared to the treatment of the underground drip interval is80cm, the depth is30cm; the irrigation quota is450mm is0.55%.(2) Underground drip irrigation water consumption in the whole growth period of alfalfa is367.55～513.91mm, the water consumption of treatment flood irrigation is630.48mm, there is previous relationship between the water consumption and irrigation quota. The maximum amount is in the branching stage and bud stage. The water consumption intensity of underground drip is0.79～5.82mm/d; while in the flood irrigation is1.99～7.04mm/d. Subsurface drip-saving effect is obvious.(3) Deriving single crop coefficient approach under subsurface drip irrigation of alfalfa crop water requirement is547.75mm, the average growth period of crop coefficient of0.96. Each growth stage alfalfa crop water requirements with a single crop coefficient approach is generally greater than the calculated field measured crop water requirements, especially the initial growth period. It has a certain relationship with subsurface drip irrigation methods. Altay region when using single crop coefficient approach Deriving alfalfa crop water requirements can be based on different ways of laying drip tape, multiplied by the appropriate correction factor.A comprehensive analysis of the above conclusions, the appropriate layout of underground drip irrigation for Alfalfa in North Aletai area is80cm, drip tape depth is30cm, the irrigation quota in the whole growth period is375mm. Water consumption in the whole growth period is462.75mm, the water consumption intensity is0.93～5.72mm/d, the maximum water consumption intensity5.72mm/d appears in the second stubble budding and blossom period.the maximum water requirement modulus appears in the branching to budding stage.