粤东七目嶂自然保护区桫椤群落维管植物多样性研究

Study on the vascular plant diversity of Alsophila spinulosa community in Qimuzhang,East Guangdong

采用植物群落学、区系学等方法,对保护区内桫椤群落及物种多样性、物种区系成分、生活型谱和群落结构等进行研究。调查表明:(1)群落范围内有46科66属78种的维管植物,其中的蕨类植物有9科9属11种,被子植物有37科57属67种。(2)生活型谱中以高位芽植物为主,约占58%。(3)科和属的分布型均以热带分布型为主,均超过65%;(4)群落垂直分层显著,乔木层的树高所占比例最大的是在4—16 m,约占77%;灌木层最大是在0—2 m,约70%;草本层的各区间分布在0—0.4 m的比例比较大,群落层次比较明显。乔木层和灌木层的平均高度均低于沟谷附近其他地段的植物群落,很可能是沟谷特殊的生境和一些人为的干扰所致。(5)群落植物多样性较丰富,物种丰富度、Shannon-Wiener多样性指数、均匀度指数、Simpson指数、Margalef指数均高于周边的风水林。加强对保护区内桫椤的生态监护,在合适地段种植和栽培以扩大种群规模,从而更有利于保护桫椤种群。

In this paper,the community and species diversity,floristic composition,life form spectrum and community structure of Alsophila spinulosa in the reserve were studied by means of phytocoenology and floristics.The results showed that:(1)there were 78 vascular plants in 66 genera,46 families in the community,including 11 ferns,belonging to 9 genera and 9 families,and 67 angiosperms,belonging to 57 genera,37 families.(2)In the life-type spectrum,high bud plants were dominant,accounting for about 58%.(3)The distribution types of families and genera were mainly tropical,which were over 65%.(4)The vertical stratification of the community was significant,the proportion of tree height in the tree layer was the largest in 4-16 m,about 77%;the shrub layer was the largest in 0-2 m,about 70%;the proportion of each interval distribution in the herb layer was relatively large in 0-0.4 m,and the community level was more obvious.The average height of tree layer and shrub layer was lower than that of other areas near the valley,which was probably caused by special habitat and some artificial disturbance.The plant diversity of the community was abundant,and the species richness,the index of Shannon-Wiener diversity,evenness,Simpson and Margalef were all higher than those of the surrounding geomantic forest.It is more beneficial to protect the Alsophila spinulosa population by strengthening the ecological monitoring of cormorants in protected areas,planting them in suitable areas to expand the population size.