本文采用回归饱和最优设计 ,对宁南三区 3种不同立地农田生态系统影响春小麦产量地氮肥和磷肥的用量进行了长期定位研究。建立了春小麦施肥效益函数模型 ,通过对函数模型分析 ,确定了最大产量效应和最佳经济效应的施肥组合方案 ,明确了模型因素效应顺序和高产施肥的关系 In this paper, the optimal design of regression saturation was used to study the long-term location of nitrogen and phosphorus fertilizers affecting the yield of spring wheat in three kinds of farmland ecosystems in the three districts of Ningnan. The fertilization benefit function model of spring wheat was established. Through the analysis of function model, the fertilization combination scheme of maximum yield effect and optimal economic effect was established, and the relationship between the order of model factor effect and high-yield fertilization was clarified