肥料效应方程经济合理施肥量是以获得最大的经济效益为原则。在肥料资源充裕的条件下，应充分发挥土地的增产潜力，提高单位面积的施肥利润，增加总收益，施肥量应以经济最佳施肥量为限，到达经济最佳施肥量时，边际产量（指增加单位量肥料所增加的总产量）等于肥料和产品的价 Fertilizer effect equation Economical and reasonable amount of fertilizer is based on the principle of obtaining the greatest economic benefits. Under the condition of abundant fertilizer and resources, the yield potential of land should be fully utilized, the fertilization profit per unit area should be increased, and the total revenue should be increased. The amount of fertilizer should be limited to the optimal economic fertilizer amount. When reaching the optimal economic fertilizer amount, the marginal product Refers to the increase of total output of fertilizer per unit of output) is equal to the price of fertilizers and products