红崖山灌区不同灌溉定额下灌溉水转化规律研究

Research on Irrigation Water Transformation Under Different Irrigation Quota in Hong ya-shan Irrigation Area

通过土壤墒情监测系统水分传感器和微型蒸渗器测定了不同灌溉定额下农田种植作物和裸地条件下土壤水分动态变化规律,初步提出了民勤红崖山灌区灌溉水深层渗漏的零通量面ZFP为地表以下120cm处,并结合气象数据比较不同灌溉定额下灌溉水转化规律及蒸散发特征,提出了作物生育期适宜的灌水定额上限,在考虑节水效益、土壤质地及灌溉时段等情况下,无论有作物覆盖还是无作物覆盖,农田灌水定额均不能大于1 200m3/hm2。这一结果对合理控制土壤水的无效渗漏、制定配水计划和节水灌溉制度提供了依据。

The soil moisture dynamic change rule under the condition of farmland with or without planting crops and different irrigation quota was determined through soil moisture sensors and micro permeability steamer of soil moisture monitoring system.It is put forward that the deep irrigation water leakage zero flux plane is 120 cm below the surface in Minqin Hongya-shan irrigation area.Combined with meteorological data,through comparing the irrigation water transformation rule and characteristics of evaporation under different irrigation quota,the suitable upper irrigation quota limit in crop growth period is proposed.Considering the aspects of benefit,soil texture and irrigation time,the farmland irrigation quota can not be greater than 1200m3/hm2 either for the condition of crop-covering or no crop-covering.The results provide a basis for reasonably controlling the soil water leakage and determining the water distribution plan and water saving irrigation system.