本文推导出描述同龄纯林的林龄分布结构动态变化规律和特点的数学物理方程：它描述了同龄纯林这一森林类型的生灭过程，为同龄纯林的面积资源预测及监测、面积的林龄结构调整及最优控制、面积资源的最优模拟等研究建立了数学模型并提出了计算方法． This paper deduces the mathematical physics equation that describes the regularity and characteristics of the dynamic change of forest age distribution structure of the pure forest of the same age. It describes the birth and death process of the pure forest of the same age, which is the prediction and monitoring of the area resource of pure forest of the same age, The age structure adjustment and the optimal control, the optimal simulation of area resources and so on, establishes the mathematical model and puts forward the calculation method.