涌泉根灌条件下灌水定额对枣树土壤水分动态变化及水分利用的影响

Effects of Irrigation Quota under Bubbled-root Irrigation on Soil Water Dynamic Changes and Water Use Efficiency of Jujube

【目的】明确枣树涌泉根灌灌水定额。【方法】以陕北山地枣树为研究对象进行了非充分灌溉试验,探明不同灌水定额对涌泉根灌条件下山地枣树各生育期的土壤水分动态变化及水分利用效率的影响。【结果】涌泉根灌方式是由地表以下枣树根部进行灌水,土层深度方向含水率随灌水定额的增大而增大;与灌前相比较,灌后各处理在土层深度0～100 cm范围内土壤含水率分别较灌前高2.35%、3.66%和4.49%。土壤含水率分布近似为椭圆形,并在60～80 cm范围达到最大,不同灌水定额与不同灌水次数对土壤水分的影响在土层深度30～60 cm范围可以得到较好的表征。枣吊前期生长受温度影响较大,灌水定额越大,枣吊生长受抑制程度越高,随着气温回升,灌水定额越大,枣吊生长越快,而灌水次数对枣吊生长的影响并不显著。灌水次数相同,随灌水定额的增大,枣树产量越高,WUE与WUEi均越小;灌水定额相同,随灌水次数的增加,枣树产量越高,WUE与WUEi均越低。【结论】T1(灌水定额75 m3/hm2)以更低的灌水投入获得相对更高的产量,为本试验条件下最经济的灌溉方案。

【Objective】To determine irrigation quota under bubbled-root irrigation of jujube. 【Method】The non-sufficient irrigation experiments were conducted on jujube trees in northern Shaanxi to explore the effects of different irrigation quotas on the dynamic changes of soil moisture and water use efficiency at different growth stages of mountain jujube trees under the conditions of Bubbled-root irrigation.【Result】The results showed that the irrigation method of Bubbled-root irrigation was performed by the roots of jujube trees below the surface. The water content in the depth direction of the soil increased with the increase of the irrigation quota. Compared with the pre-irrigation, Soil water content within 100 cm was higher than 2.35%, 3.66% and 4.49%. The distribution of soil water content was approximately elliptic and reaches the maximum in the range of 60~80 cm. The effects of different irrigation quotas and different irrigation times on soil moisture can be well characterized in the soil depth range of 30~60 cm. The growth of the early stage of jujube hanging was influenced by temperature. The larger the irrigation quota, the higher the suppression of jujube hanging growth. With the temperature rising, the larger the irrigation quota, the faster the jujube hanging growth, and the impact of irrigation times on jujube hanging growth was not obvious. With the same number of irrigation times, with the increase of irrigation quota, the higher the output of jujube, the smaller the WUE and WUEi;the same irrigation quota, the higher the output of jujube, the lower the WUE and WUEi.【Conclusion】T1 (Irrigation Quota 75 m3 /hm2), with relatively lower irrigation inputs, yields relatively higher yields, making it the most economical irrigation scheme under the conditions of the trial.