【摘要】 基于粤北始兴县罗坝保护区内 2个 2 5 0 0m2 样地的群落分层频度调查数据 ,以不同林层作为一维资源位状态 ,以个体多度为生态位计测的资源状态指标 ,对天然常绿林群落中的 12个优势树种 (栲树、马尾松、荷木、枫香、罗浮柿、杨梅、鹿角栲、黄瑞木、甜锥、山杜英、牛耳枫及鸭公树 )进行了生态位的计测和分析 .结果表明 ,大部分的耐荫树种具有较大的生态位宽度值 ;而阳性树种 (如马尾松等 )则表现为较小的生态位宽度值 .其中马尾松和枫香的生态位宽度值为 0 ,与这两个种在群落演替中的衰退地位相一致 .各优势树种 ,无论是耐荫种类抑或是阳性种类 ,均表现出一定程度的对现有环境适应的相似性 .群落 1中相似性比例在 0 .5以上的占 5 4.5 % ;也表现出一定程度的生态位重叠 ,群落 1中重叠值大于 0 .2的占 5 1.5 % .结合经典的森林群落分层频度分析 ,则可以更准确地判定种群在群落中的地位和更新发展潜力 ;另一方面 ,把群落分层作为资源位 ,考虑不同的个体多度在分层中的分布情况 ,这些分析结果也从一个侧面反映树种对生境的要求情况 .不同的群落由于其中树种组成结构不同 ,使树种生态位宽度值产生变化 ,从而影响树种之间的生态位相似比例和生态位重叠值 .更多还原

【Abstract】 Two communities of the natural evergreen forest in Luoba Nature Reserve, North Guangdong, each represented by a 2500m2 plot, were surveyed with Tree-layer-frequency method. Based on these data,the niche characteristics of 12 dominant populations, i.e.,Castanopsis fargesii,Pinus massoniana,Schima superba,Liquidambar formosana,Diospyros morrisiana,Myrica rubra,Castanopsis lamontii,Adinandra milletii,Castanopsis eyrei,Elaeocarpus silvestris,Daphniphyllum calycinum,Neolitsea chuii,were described and analyzed, with stand layer as the resource state and tree abundance as the resource state descriptor of niche. The results indicate that most of the shade-tolerant tree species have higher niche breadth values, while the intolerant tree species have the lower ones, with zero value for Pinus massoniana and Liquidambar fomosana, which is in accordance with the declining status of the two species in the community. All the dominant populations, both shade-tolerant and intolerant, showed some adaptation to the community environment. 54.5% of the population-links had a niche similarity over 0.5, and 51.5% of them had a niche overlap over 0.2 in community 1. Niche characterization combined with conventional Tree-layer-frequency method could better determine the status and regenerating potential of tree species in the community. On the other hand, measuring tree abundance in different stand layers as the resource niche could demonstrate tree’s requirement for the habitat. Variations in tree composition result in varied niche breadth, which lead to the variations of niche similarity and niche overlap values.更多还原