基于土壤水势的棉花滴灌预警模型研究

Study on Warning Model of Cotton Drip Irrigation Based on Soil Water Potential

[目的]研究膜下滴灌棉花不同土层深度土壤水势变化及与棉花功能叶片水势之间的关系,实现土壤水分的实时监测。[方法]利用水势测定仪测定土壤水势,并建立基于土壤水势的棉花滴灌预警模型。[结果]土壤水势在20~40 cm土层变化幅度较大,土壤水势(x)与棉花功能叶的凌晨叶水势(y)之间的关系:0~20 cm土层的方程式为y=-0.000 7x^2-0.028 3x-1.394 3(R^2=0.964 3),20~40 cm土层的方程式为y=-0.000 8x^2-0.046 6x-1.8 093(R^2=0.948 2)。通过田间验证预测精度较高(R^2=0.945 7)。[结论]该研究为膜下滴灌棉花灌溉补水和水分实时监测预警提供参考。

[ Objective] To study the relationship between soil water potential changes of cotton under mulched dip irrigation in different soil depth and water potential of cotton function leaf,and realize the real-time monitoring of soil moisture. [ Method] Soil water potential was measured using water potential instrument, and early warning model of cotton drip irrigation based on soil water potential was established. [ Result ] Change amplitude of soil water potential （SWP） was maximum in soil layer of 20 -40 cm, and the relationship between soil water potential （x） and leaf water potential of function leaves （y） in the morning：equation in 0 -20 cm soil layer for y =0. 000 7x^2 -0. 028 3x - 1. 394 3 （R^2 =0. 964 3） ,equation in 20 - 40 em soil layer for y = 0. 000 8x^2 - 0. 046 6x - 1. 809 3 （R^2 = 0. 948 2）. Through the field validation prediction accuracy was higher （R^2 = 0. 945 7）. [ Conclusion ] The study can provide theoretical reference for filling water and real-time monitoring and early warning.