干旱区绿洲滴灌成龄枣树耗水规律及作物系数

Jujube Drip Irrigation Water Consumption and Its Crop Coefficient in Oasis of Arid Areas

【目的】研究不同水分处理对成龄枣树各生育期土壤水分动态变化、耗水量及作物系数的影响,为滴灌枣树灌溉制度和灌溉预报提供依据。【方法】利用水量平衡法和彭曼-蒙特斯公式计算枣树各生育期耗水量和参考作物蒸腾量,探明滴灌成龄枣树的耗水规律及确定作物系数。【结果】参考作物ET0呈两头低中间高的抛物线趋势;灌水定额105 m^3/hm^2处理的灌水量相对较小或者灌水周期过长,入渗深度达到50 cm,枣树的耗水量大于灌水量;灌水定额165 m^3/hm^2处理水量和灌水周期相对合理,入渗深度达到70 cm;灌水定额225m^3/hm^2处理的灌水量相对较大或者周期过短,入渗深度达到80 cm。枣树全生育期耗水量在5 796-6 682m^3/hm^2,各生育期耗水量对比：开花坐果期〉果实膨大期〉果实成熟期〉萌芽展叶期。开花坐果期和果实膨大期耗水模数在71%-77%;萌芽展叶期作物系数0.74-0.86;开花坐果期作物系数1.24-1.36;果实膨大期作物系数1.22-1.45;果实成熟期作物系数0.63-0.92。【结论】参考作物ET0呈两头低中间高的抛物线趋势;灌水定额165 m^3/hm^2处理灌水量和灌水周期相对合理;开花坐果期和果实膨大期耗水模数在71%-77%,属于需水关键期。作物系数是个范围值,萌芽展叶期作物系数0.86;开花坐果期作物系数1.36;果实膨大期作物系数1.22;果实成熟期作物系数0.83。

【Objective】To study the soil moisture dynamic,water consumption and crop coefficient of jujube during the growth period by different water treatments and provide the basis for jujube drip irrigation system and irrigation forecasting. 【Method】The method of water balance and Peng Man-Montes formula was used to calculate jujube water consumption at various stages and the reference crop transpiration in order to find out the water consumption law and make sure the crop＇s coefficient. 【Result】The reference crop ET0 is low at both ends and high in the middle which displayed a parabolic trend. The Irrigation quota of 105 m^3/ hm^2 treatment was rather small or took a long cycle of irrigation. If the infiltration depth was up to 50 cm,jujube water consumption was greater than the irrigation water. If the irrigation quota was 165 m^3/ hm^2,the irrigation cycle was relatively reasonable,and when the infiltration depth was up to 70 cm,irrigation quota of 225 m^3/hm^2 treatment was large with a shorter cycle. When the infiltration depth was up to 80 cm,water consumptionwas between 5 796-6 682 m^3/ hm^2 in the whole stage. During the whole growth period,the water consumption amount was： flowering fruit-bearing stage〉 fruit enlargement stage〉 fruit mature stage bud exhibition leaf stage. The period of flowering fruit and fruit enlargement period,water consumption modulus was between 71%-77%; Bud exhibition leaf stage crop coefficient was 0. 74-0. 86; Flowering fruit crop coefficient was1. 24-1. 36; Fruit enlargement period crop coefficient was 1. 22-1. 45; Mature fruit crop coefficient was 0.63-0. 92. 【Conclusion】The reference crop ET0 is low at both ends and of high in the middle showing a parabolic trend; Irrigation quota of 165 m^3/ hm^2 of water and irrigation cycle is relatively reasonable; The period of flowering fruit and fruit enlargement period,the water consumption modulus was between 71%-77%,which belonged to the critical period for water requirement. At the bud exhibition leaf stage,crop coefficient was 0. 86; At the fruit flowering and setting stage,the crop coefficient was 1. 36; And at the fruit enlargement period crop coefficient was 1. 22; It was 0. 83 in the mature period.