用竞争密度效果的倒数式分析了 I- 6 9杨 (Populusdeltoids)的生长过程。随着时间的推移 ,C- D曲线在双对数图上向上移动。生物时间τ(τ被定义为逻辑斯蒂生长曲线中生长系数λ(t)的积分 )与物理时间 t的关系可以用双曲线方程表示。 C- D效果倒数式 (即 1/ w =Aρ+B,式中 w和ρ分别代表平均单株材积和密度 )中的系数 A和 B被求出。随着生物的时间τ的增加 ,系数 A急剧增加到最大值后逐渐下降 ,而系数 B呈指数下降 ,倾向于接近零。随着林分的生长 ,生长系数λ(t)倾向于下降 The growth of I-6 9 Populus deltoids was analyzed by reciprocal of competitive density effect. As time goes on, the C-D curve moves up on the double logarithmic graph. The biological time τ (τ is defined as the integral of the growth factor λ (t) in the logistic growth curve) and the physical time t can be expressed by the hyperbolic equation. The coefficients A and B in the reciprocal C-D effect (ie 1 / w = Aρ + B, where w and p represent the mean individual plant volume and density, respectively) are found. As the biological time τ increases, the coefficient A increases sharply to a maximum and then decreases gradually, while the coefficient B decreases exponentially and tends to approach zero. With the growth of the forest, the growth coefficient λ (t) tends to decrease