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研究结果表明,该种群的年龄结构由一至数个相间隔的年龄波组成。据此,可将该种群的年龄结构划分为一代型、两代型和多代型三大类,进一步又可按世代(年龄波)的构成状态细分为11种类型。自然干扰因素对年龄结构具有重要影响。绝大多数年龄波的出现都与森林火有关。风倒、风折亦有影响,但其作用只能从新近发生的幼小一代中看出。高频、低强度的森林火利于形成两或多代型的年龄结构;而低频、高强度的森林火则利于形成一代型的年龄结构。不同地段自然干扰状况的差异是造成多种年龄结构类型共存的主要原因。年龄波,做为年龄结构的基本构成单元,具有明显的β分布特点。年龄波的形状大致可分为右偏、左偏、递减分布和递增分布四种类型。不同形状的年龄波与种群环境有关,是种群更新过程的综合反映。
The results show that the age structure of the population consists of one to several spaced age waves. Accordingly, the age structure of the population can be divided into three major types: generation type, two generation type and multi-generation type, and further subdivided into 11 types according to the generation state (age wave). Natural disturbance has an important influence on the age structure. The appearance of most age waves is related to forest fire. Wind down, wind break also have an impact, but its role can only be seen from the newly emerged young generation. High-frequency, low-intensity forest fire is conducive to the formation of two or more generations of age structure; and low-frequency, high-intensity forest fire is conducive to the formation of a generation of age structure. The differences in natural disasters in different locations are the main reasons for the coexistence of various age structure types. Age wave, as the basic structural unit of age structure, has obvious distribution characteristics of β. The shape of the age wave can be divided into four types: right deviation, left deviation, decreasing distribution and increasing distribution. Age waves of different shapes are related to the population environment and are a comprehensive reflection of the population renewal process.