产芝水库灌区农田水分转化及节水灌溉模式分析

Analysis on field water balance and water-saving irrigation modes in Chanzhi Reservior irrigation area

在长期田间试验的基础上,建立了产芝水库灌区典型农田的土壤水分运动模型。结果表明,常规灌溉条件下灌区农田水分的无效渗漏量较大,降水和灌溉与土壤深层渗漏和农田蒸散量之间存在明显的正相关关系。基于作物的土壤水分调节标准,模拟得到灌区不同降水年型的节水灌溉模式,与常规灌溉相比,节水灌溉模式在丰水年可节省水240mm,平水年140mm,枯水年为90mm,并且农田渗漏量显著低于常规灌溉,丰水年、平水年和枯水年的全年平均农田渗漏强度分别减少了0.66、0.35和0.27mm/d。在作物关键生育期合理控制灌水量,能够保证作物正常需水的同时减少土壤水的无效渗漏,从而提高灌溉水的利用效率。

This paper establishes soil water movement model of typical farmland in Chanzhi Reservior irrigation area based on long-time field experiment.The results indicate that leakage of soil water is almost serious under conventional irrigation mode,precipitation and irrigation show positive correlation with water leakage and field evapotranspiration.Water-saving irrigation modes under the condition of different hydrographic years were simulated based on soil water adjustment criterion,in contrast with conventional irrigation,it could save water 240 mm in wet year,140 mm in medium precipitation year,and 90 mm in draught year,respectively.Simultaneity,the amounts of water leakage under water-saving irrigation modes are significantly less than conventional irrigation,the leakage intensities of wet year,medium precipitation year,and draught year decrease by 0.66,0.35 and 0.27 mm/d,respectively.Due to the reasonable control of irrigation in the key growth stages of crop,the amount of water leakage decreases while meeting water requirement for crop.So it can improve the utilization efficiency of irrigation water.