黄土高原中国沙棘克隆种群高度结构动态

为了解黄土高原中国沙棘种群演替规律,以人工林为材料、以高度替代年龄为手段,采用＂空间差异代替时间变化法＂和＂样地编年序列法＂对种群结构类型及其动态进行分析。结果表明：种群高度结构可划分为增长型、稳定型和衰退型,种群结构动态遵循增长型、稳定型、衰退型、恢复型、增长型的顺序变化过程。上述结果与种群年龄结构动态分析一致,两者都揭示了中国沙棘通过林窗更新恢复种群结构稳定性这一特殊而重要的事实。其中,克隆种群结构由增长型经过稳定型发展到衰退型,这一过程符合阳性树种的普遍演替规律。而在衰退型种群中,中国沙棘通过克隆繁殖调节恢复增长型种群结构则体现了克隆植物的特殊性。同时,克隆种群稳定性恢复的实现与克隆植物独有的＂生理整合＂及＂觅养行为＂等优越性密切相关。

Height-class Structure Dynamics of Hippophae rhamnoides ssp.sinensis Clone Population in the Loess Plateau

In order to understand the succession regularity of Hippophae rhamnoides ssp.sinensis clone population in the Loess Plateau,taking the plantation as study materials and using the means of height-class instead of age-class,the structure types and dynamics of clone population were analyzed with the methods of spatial series substituting for time series and sample plots serial arranged with age.The results showed that the height-class structures of clone population can be divided into increasing type,stable type and decreasing type.Population structure dynamics followed the changing processes in order,which were from increasing type to stable type then decreasing type and through recovery type restoring to increasing type finally.The results mentioned above were consistent with the dynamics analysis of clone population age-class structures,and both revealed the special and important facts that the population could restore its structure stability through the gap regeneration.The dynamics of height structure from increasing type to stable type and then to decreasing type were corresponded with the general succession regularity of heliophyte tree.But in the decreasing type of clone population,H.rhamnoides ssp.sinensis could restore its increasing structure through clonal propagation regulating and this reflected the particularity of clonal plant.And the achievements on stability recovery of clone population were closely related to the clonal plant unique advantages of ＂physiological integration＂ and ＂foraging behavior＂.