本文从经济效益的角度出发,提出用经济成熟龄确定伐期龄。即以单位面积上云杉天然林年平均经济收入最大值作为目标函数,求出不同地位级云杉林的经济成熟龄。并计算了不同龄级的损益值。进一步阐明了达到经济成熟龄时采伐的经济效益为最佳。提前或推后采伐,在经济上都不合算。同时也提出了由林分平均胸径推算经济成熟龄,为科学经营森林提供了依据。 This article from the perspective of economic efficiency, proposed the use of economic mature age to determine the cutting age. That is, taking the maximum annual average economic income of natural spruce forest per unit area as the objective function, the economic maturity age of spruce-fir forest at different positions was obtained. And calculated the profit and loss value of different age groups. Further clarified the economic benefits of harvesting when the economic mature age is the best. Logging ahead of schedule or postponing is uneconomical. At the same time, it also proposed that the average age at breast height should be used to calculate the economic maturity and provide the basis for scientific management of forests.