五鹿山国家级自然保护区油松群落优势种生态位研究

根据五鹿山国家级自然保护区油松群落57个样地调查资料，通过TWINSPIN聚类分析对该群落类型进行了划分，将划分群丛类型作为资源轴，计算了乔木和灌木树种Shannon-Wiener和Hurbert生态位宽度及Morisita重叠指数。结果表明：油松群落共划分为7个群丛。乔木层油松、辽东栎、茶条槭的生态位宽度（Shannon-Wiener和Hurbert生态位宽度）较大，LB和HB分别是1.656、1.404、1.047和0.948、0.735、0.386。灌木层水栒子、土庄绣线菊、陕西荚蒾的生态位宽度较大，LB和HB分别是1.562、1.401、1.300和0.512、0.447、0.389。乔木层生态位高度重叠的占6%(>0.8)，中度重叠的占10%(0.6~0.8)，小于0.6的低度重叠的占84%，灌木层高度重叠者占7%(>0.8)，中度重叠者占10.39%(0.6~0.8)，小于0.6的低度重叠者占82.25%。说明油松群落组成植物对当地环境具有较高的适应性和资源环境利用能力，种间竞争较小，有些物种的生态位明显趋于特化，群落处于共摊阶段。

Niche Analysis of Pinus tabulaeformis Community Dominant Species in Wulu Mountain Nature Reserve

According to the data of 57 plots, Pinus tabulaeformis community from Wulu Mountain Nature Reserve was classified by TWINSPIN cluster analysis. Shannon-Wiener, Hurbert niche width and niche overlap of Morisita Index of the type of tree and shrub were calculated by utilizing the type of association as a resource axis. The results showed that P.tabulaeformis, Quercus wutainnesis and Acer ginnala had larger Shannon-Wiener values which were 1.656, 1.404 and 1.047, respectively and Hurbert niche width values were 0.948, 0.735 and 0.386, respectively, in the tree layer. Cotoneaster multiflorus, Spiraea pubescens, and Viburnum schensianum had larger Shannon-Wiener values which were 1.562, 1.401 and 1.300, respectively and Hurbert niche breadth values were 0.512, 0.447 and 0.389, respectively, in the shrub layer. The niche overlapping of tree layer included three degrees which consisted of high overlap, moderate overlap and low overlap, high overlap accounted for 6% (>0.8), moderate overlap accounted for 10% (0.6-0.8) and low overlap accounted for 84%. Besides, the niche overlapping of shrub layer also included three degrees which consisted of high overlap, moderate overlap and low overlap, high degree overlap accounted for 7% (>0.8), moderate overlap accounted for 10.39% (0.6-0.8), and low overlap accounted for 82.25%. As succession proceeding, P.tabuliformis had higher adaptability and the ability of using resources, and lower inter-specific competition in the local environment. However, the niches of some species obviously tended to specialize, the community was in the polled stage.