单点滴灌模式干旱区枣园土壤水分运移特征分析

Analysis on the Characteristics of Soil Water Transfering in Jujube Orchard under Conditions of Single Drip Irrigation in Arid Region

在阿克苏佳木试验站枣树果园进行了单点滴灌灌水方式12,16,20L/h滴头流量和4,6,8h滴水时间共9种灌水模式试验,采用土壤含水量连续监测系统(AV-EC5、EM50/R)监测并分析了土壤水分时空运移特征。结果表明,单点滴灌灌水方式下湿润体内土壤含水量的分布从中心向外逐渐减小,土壤水分按点源三维入渗方式运移,湿润层呈扇形剖面;供水停止后土壤水分再分布过程中,土壤湿润峰面不断向外部推移,湿润层土壤含水量开始有所增加,后期湿润体内的土壤含水量普遍降低,高含水区逐渐下移,最后达到相对稳定;滴头流量越大,灌溉时间越长湿润层能达到的深度越深,水平方向水分运移也越远;深层土壤水分持续增加时间也与滴头流量和灌溉时间成正比;试验地土壤水分水平运移速度比垂直运移速度快;当地枣树果园滴灌模式选择16L/h流量8h灌溉模式为宜。

The experiments in the jujube orchard in Jamu experimental Station,Aksu District,Xinjiang by the suse of a kinds of irrigation method with single drip irrigation of 12,16,20 L/b flow rate and 4,6,8 h drip irrigated time were surveyed by use of the soil moisture content continuous monitering system （AV- ECS,EmS0/R） and the characteristics of soil moistrue spatial transfering were analyzed. The results showed that, soil water content distribution is reduced gradually from center to outward, and the soil water in moist body moved by three-dimensional flow and the moist layer was of fan-shaped section. In the course of soil water redistribution after stopping water,the soil moist peak surface was developed to outside. The moisture content of the moist soil layer began to be increased and soil moisture content of moist body was reduced generally at the late period. The area with high water moisture moved down gradually and soil wa- ter content was relatively stable finally. The greater the water droppers, the longer the irrigation time, the deeper the moist layer moved to depth, the longer the water moved at horizontal level. There was direct proportion between the time of continuously increasing water in the soil of deep layer and the flow of water droppers and irrigation time;The velocity of soil water vertical movement in the test field was faster than that of horizontal movement;The method of 16 L/h flow rate and 8 h irrigated time was the best for local jujube tree soil.