滇中地区元江栲群落物种多样性及其关联因子

Species Diversity and Its Associated Factors of Castanopsis orthacantha Community in Central Yunnan

为准确掌握滇中地区元江栲群落的物种多样性水平及其与相关因子的关系,在设置典型样地调查的基础上,采用Margalef丰富度指数、Pielou均匀度指数、Shannon-Weiner多样性指数以及物种多样性综合指数测度元江栲群落的物种多样性水平,结合灰色关联分析法探究物种多样性水平与立地因子、林分因子以及林地干扰强度的关系。研究表明:1)元江栲群落物种组成较丰富,共涉及75科141属202种,以灌木层(含更新层)物种组成最为复杂,乔木层树种组成具有典型亚热带常绿阔叶林特征,不同区域物种组成及重要值差异明显。2)丰富度指数、多样性指数和均匀度指数均表现为灌木层(含更新层)最高,元江栲群落物种多样性整体呈中等水平,研究区内不同调查区域间物种多样性具有不同程度的差异。群落草本层和灌木层(含更新层)对群落物种多样性综合指数贡献率最大。3)物种多样性与立地因子、林分因子和林地干扰强度3个层面的6个因子间都表现出较强关联性,关联度大小排序为海拔>林地干扰强度>平均胸径>坡向>株数密度>坡度。通过研究,以期为滇中地区元江栲群落的修复和保育措施的制定提供依据。

In order to accurately grasp the species diversity level of Castanopsis orthacantha community and its relationship with related factors in central Yunnan,based on the investigation of typical plots,the Margalef richness index,Pielou evenness index,Shannon-Weiner diversity index and species diversity comprehensive index were used to measure the species diversity level of Castanopsis orthacantha community,and the grey correlation analysis method was used to explore the relationship between species diversity level and site factors,stand factors and forest disturbance intensity.The results showed that:1)The species composition of Castanopsis orthacantha community was rich,involving 75 families,141 genera and 202 species,and the species composition of shrub layer was the most complex.The tree species composition of the arbor layer had the characteristics of typical subtropical evergreen broad-leaved forest.And there were significant differences in species composition and important values in different regions.2)The richness index,diversity index and evenness index of shrub layer(including regeneration layer)were the highest,and the species diversity of Castanopsis orthacantha community was at a medium level.The species diversity of different survey areas in the study area was different.The contribution rate of herb layer and shrub layer(including regeneration layer)to the comprehensive index of community species diversity was the highest.3)There was a strong correlation between species diversity and six factors in three levels of site factors,stand factors and forest disturbance intensity.The order of correlation degree was altitude>forest disturbance intensity>average DBH>aspect>plant density>slope.Through research,the aim is to provide a basis for the restoration and conservation measures of Castanopsis orthacantha community in central Yunnan.