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通过分析不同择伐强度下思茅松(Pinus kesiya)天然林乔木种群的生态位、种间联结、种内与种间竞争和群落稳定性,探讨干扰强度对思茅松天然林乔木种群种间与种内关系的影响。结果表明:(1)择伐干扰改变了大多数乔木树种在群落中的优势地位,思茅松优势地位未受影响,随着择伐干扰强度的增加,思茅松在群落中的生态位宽度逐渐变大,在重度干扰的群落中与红木荷(Schima wallichii)一起成为生态幅度最大的树种。(2)通过种间联结与生态位重叠分析发现,随着干扰强度的加剧,乔木种群的种间关系发生变化,中度干扰群落中物种之间的生态位重叠明显高于未干扰和重度干扰群落,而在三类群落中,思茅松与其他种群之间的重叠值较小。随着干扰强度增加,种群间正联结与负联结的种对所占的比例逐渐增加。(3)Hegyi竞争指数表明,三类群落中思茅松种群的竞争压力主要来自种间,而干扰强度进一步增加了思茅松种群的种间竞争强度,其种内平均竞争指数随着对象木胸径的增加而减少。(4)林窗是思茅松种群种间和种内关系变化的主要原因,三类群落都处于较不稳定的阶段,但中度干扰群落的物种丰富度与稳定性都高于未干扰和重度干扰的群落。择伐原则依据森林管理的目的而确定,如以木材培育为主或森林生态系统服务功能为主。
By analyzing the niche, interspecific association, intraspecific and interspecific competition and community stability of natural populations of Pinus kesiya under different selective densities, the effects of disturbance intensity on the spatial variability of tree species in Pinus kesiya natural forest The impact of internal relations. The results showed that: (1) Selective disturbance changed the dominance of most arbor species in the community, and the dominant position of S. sinensis was unaffected. With the increase of selective disturbance, the niche breadth of Pinus kesiya in the community gradually changed Larger, together with Schima wallichii in the heavily disturbed community, became the most ecologically important tree species. (2) Through interspecific association and niche overlap analysis, it was found that with the intensification of disturbance intensity, the interspecific relationships of arbor population changed. The niche overlap among species in moderate disturbance community was significantly higher than that of undisturbed and severe disturbance However, in the three communities, the value of overlap between the two populations was smaller. With the increase of disturbance intensity, the proportion of species pairs with positive and negative associations between populations gradually increased. (3) The Hegyi competition index indicates that the competitive pressure of S. sinensis population in the three communities mainly comes from interspecies, while the intensity of disturbance further increases the interspecific competition intensity of S. sinensis population. The average intra-species competition index varies with the DBH Increase and decrease. (4) Gap was the main reason for the change of interspecific and intraspecific relationships in Pinus kesiya var. Mangei population. All three communities were in a less stable stage, but the species richness and stability of the moderately disturbed community were higher than that of the uninterrupted and severe Interfered with the community. The principle of selective cutting is determined according to the purpose of forest management, such as mainly timber cultivation or forest ecosystem service function.