贵州濒危树种岩生红豆森林群落特征及种群结构

Community Characteristic and Population Structure of Ormosia saxatilis in Guizhou Province

通过典型群落样地调查，对不同干扰强度下岩生红豆所处森林群落特征及种群结构进行了研究，结果表明，（1）该种群所处群落乔木层物种较为丰富，多样性指数（SW）为2．66—3．26，生态优势度（E1））为0．11～0．17，各群落样地之间差异不显著；（2）岩生红豆能成为局部群落建群层的次优种或共优种，但数量很少，在整个群落乔木层处于明显弱势；（3）不同干扰强度下岩生红豆种群大小级指数不同，笔架山群落种群大小级指数（SDI）为负值（-0．0037），种群连续；黔灵山的群落种群大小级指数（SDI）为正值（0．0016），种群不连续；（4）群落更新层岩生红豆幼苗、幼树的年龄结构呈倒金字塔型，I级幼苗数量较少，多为Ⅱ～Ⅳ级幼树，且数量稀少，天然更新明显不良。

Population structure and community characteristics of Ormosia saxatilis under different disturbance densities was studies by using classical community sampling approach, and the results shows that ： （ 1 ） The species diversity of tree layers in the community is rich. The diversity index （SW） is 2. 66 - 3.26, the ecological dotalnance （ED） is 0. 11 -0. 17, and there is no significant difference between different community samples ; （2） Even Ormosia saxatilis could become subdominant species or co-dominant species of some local communities, but such phenomena is few and it is usually at a disadvantage position in the whole tree layer community; （3） The grade index of Ormosia saxatilis population size are different under different disturbance densities, the SDI in Bijia Mountain is a negative value （-0. 003 7 ） with continuous population, and SD! in Qianling Mountain is positive （0. 001 6） with discrete population; （4） The age structure of the regeneration layer in the communities is an in- verted pyramid type. The number of I-grade seedlings is was small, and the most are saplings from II to IV, and natural regeneration of Ormosia saxatilis is not obvious.