旱地起垄覆膜沟播小麦氮磷钾施肥模型研究

Fertilizer model of nitrogen phosphorus and potassium on winter wheat with plastic film mulching in dryland

通过对氮磷钾肥三元二次回归正交组合设计的试验研究,建立了地膜小麦产量与氮磷钾肥的模型关系,对数学模型寻优得出了不同产量范围下的施肥范围。对边际产量与边际成本的计算得出了最佳施肥量和最高产量时的施肥量分别为:施氮、磷、钾肥量分别为157.3 kg/hm2、138.0 kg/hm2、135.2 kg/hm2和158.2 kg/hm2、138.9 kg/hm2、137.0 kg/hm2,并根据不同的施肥水平得出了地膜小麦的群体和生物学产量的变化规律。

The mathematical model has been set up to describe the relationships of grain yield with nitrogen, phosphorus and potassium by means of the design of the regression-orthogonal combination in this study. From the model, the amount of fertilizers is simulated in different grain yield. On the basis of analysis with marginal yield and marginal cost, it is put forward the optimum amount of fertilizers of NPK which either economal cost or highest yield. It was reached individually 157.3 kg/hm2, 138.0 kg/hm2, 135.2 kg/hm2 and 158.2 kg/hm2, 138.9 kg/hm2, 137.0 kg/hm2. And also pointed out the trends law of the culm number and biomass on winter wheat with different level of fertilizer application.