渭北旱塬地膜小麦施肥模型研究

Fertilizer application model on winter wheat with plastic film mulching in Weibei Dryland

采用三元二次回归正交组合设计 ,建立了不同降水年型地膜小麦产量与氮磷钾肥的模型关系 ,通过数学模型寻优得出了达到某一产量所需的最佳施肥量 ,并根据肥料的产投比得出了经济目标产量。施肥量及比例直接影响作物的水分利用效率 (WU E) ,增施肥料特别是磷肥和氮肥能显著提高地膜小麦的 WU E,钾肥对

The mathematical model has been set up to describe the relationships of grain yield to nitrogen,phosphorus and potassium in different precipitation years by means of the design of the regression orthogonal combination in this study.From the model,the optimum amount of fertilizers is simulated.Economical object yield is obtained according to the ratio of fertilizers output to input.The amount and the ratio of applying fertilizer directly affect WUE.The WUE of film mulched wheat is increased with the amout of fertilzers,especially phosphorus and nitrogen,but the effect of potassium is smaller.