温室膜下滴灌条件下黄瓜经济灌溉制度及其下限值的研究

以温室黄瓜为试验材料,采用膜下滴灌,对最适宜作物生长的温度、水分胁迫指数和干物质转化因子3个作物生长模型参数进行了率定,并以此为依据分析确定了膜下滴灌黄瓜的经济灌溉制度。结果表明:采用经济灌溉制度比实际灌水有显著的增产增收效果,产量和效益分别增加2.54t/hm~2和2.36万元/hm~2,节约灌溉水量7.59%;在经济灌溉条件下灌水前土壤含水率(0~60cm)随时间的变化幅度较作物生长期土壤含水率的变化幅度小得多,取各次灌水前土壤含水率的平均值作为作物经济灌溉的灌水下限值,对于本研究中的黄瓜,其值为0.240。按照该灌水下限值灌水,可使温室膜下滴灌黄瓜单位面积的灌溉效益最大。

Research on Cucumber Economical Irrigation Schedule and Irrigation Low Limit with Drip Irrigation Under Plastic Mulch in Greenhouse

Taking the greenhouse cucumber with drip irrigation under plastic mulch as experimental material,three crop growth model parameters of the temperature,water stress index and dry matter transformation factor are determined,and the economic irrigation schedule is determined based on the three model parameters.The results show that:the economic irrigation system can significantly increase yield and income by 2.54 t/hm2 and 23 600 yuan/hm2 than the existing irrigation schedule,and the irrigation water con-sumption is saved by 7.59%.The fluctuation percent of soil moisture content (0~60 cm)before irrigation is much smaller than that of the crop growing period.The average value of soil water content before irrigation is used as the irrigation low limit for crop eco-nomical irrigation,and the value is 0.240.According to the irrigation low limit,the irrigation benefit of the unit area of Cucumber with drip irrigation under plastic mulch in Greenhouse can be the best.