【摘要】 为揭示不同演替阶段森林群落结构与种间关联，通过时间序列法选取粤北石门台国家级自然保护区两个不同演替阶段的森林群落，并对其乔木层的物种组成、群落结构及种间关联进行了研究。运用双向聚类分析和主坐标分析对两个群落的乔木层进行了物种分布和种间关系的分析，同时采用基于2×2联立表的χ~2检验分析了该区域两个群落乔木层的种间联结性。结果表明，随着演替的进行，群落的总物种数减少，重要值较小的阳性植物逐渐消失，而耐阴植物的重要值增大。群落Ⅰ(林龄85 a)中，正联结的种对数占42.38%，负联结的种对数占57.62%，联结性达到显著水平的种对仅有11个，占总数的5.24%，体现出较强的种间独立性;群落Ⅱ(林龄65 a)中，正联结的种对数占25.32%，负联结的种对数占74.68%;种间联结性达到显著水平的种对数占35.56%。随着演替的进行，显著负联结的种对比例减少，不显著正联结的种对比例增加，说明森林群落随演替进行树种趋于和谐共存的相对稳定状态，而群落的稳定性可能通过树种独立性的提高来维持。更多还原

【Abstract】 We selected two forest stands of different successional stages in Shimentai National Nature Reserve in north Guangdong to reveal the forest structure and interspecific association in different successional stages. We used the chronosequence method to investigate the species composition, community structure, and interspecific associations of the canopy trees. We also used two-way cluster analysis, principal coordinate analysis, and the χ~2 test based on a 2×2 contingency table to analyze species distribution and interspecific associations of the canopy trees. The results showed that, with community succession, the total number of species in the community decreased, and the heliophilous plants with a low importance value gradually disappeared, while the importance value of shade-tolerant plants increased. In community Ⅰ(85 years of forest age), 42.38% species pairs had positive associations, while 57.62% of the total species pairs had negative associations. Only 11 species pairs were found to have significant interspecific associations, accounting for 5.24% of the total, indicating a strong independence of species in the community. In community Ⅱ(65 years of forest age), 25.32% of species pairs had positive associations, and 74.68% had negative associations, with significant interspecific associations found in 35.56% of the total species pairs. With the progress of succession, the proportion of species pairs with negative associations decreased, while the proportion of those with nonsignificant positive associations increased. These results demonstrate that forest trees in the communities tended to be relatively stable in coexistence with the succession progress, and community stability might be maintained by the improvement of tree species independence.更多还原