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研究了四合木种群的径级结构、冠幅结构、高度结构和年龄结构 ,运用静态生命表描述了四合木种群年龄结构动态变化规律。研究表明 :四合木种群株数随径级、高度级的变化呈“山峰型”,植株数随冠幅级变化成倒“J”型。现实的四合木种群年龄结构呈“凸”型。四合木种群的死亡率 qx、致死力 k X 随龄级增大而增高 ,存活率 lx 随龄级增大而降低。其存活曲线接近于 Deevey 型。利用L eslie矩阵定量模拟种群动态 ,发现在受外界干扰很小条件下 ,该种群具有波动特点 ,各龄级的个体数变化趋势不同 ,种群由衰退型向增长型过渡。
The diameter structure, crown width structure, height structure and age structure of Tetraena mongolica population were studied. The static life table was used to describe the dynamic changes of age structure of Tetraena mongolica population. The results showed that: the number of Tetraena mongolica populations was “mountain-type” with the change of diameter and height, and the number of plants changed into “J” with crown width. The realistic age structure of Tetraena population was “convex” type. Tetragena population mortality qx, lethal force k X increased with age and increased survival rate lx decreased with age. Its survival curve is close to Deevey type. Using the L eslie matrix to quantitatively simulate the population dynamics, we found that under the condition of little interference from outside, the population has the characteristics of fluctuating, the individuals of all ages have different trends, and the population transitions from declining to growing.