平潭岛不同演替阶段植被群落物种多样性特征

Species Diversity Characteristics of Vegetation Communities in Different Succession Stages in Pingtan Island

以平潭岛天然次生林为研究对象,分析灌草丛、针叶林、针叶混交林、常绿阔叶林群落的物种组成、重要值、物种多样性特征的变化,探讨平潭岛与邻近海岛和大陆的群落物种多样性差异。结果表明:4种群落类型共有53科89属104种植物,群落类型间及各层次的丰富度、多样性、均匀度从灌草丛到针阔混交林阶段呈上升趋势,阔叶林阶段呈下降趋势。群落各层次的丰富度、多样性变化,乔木层为针阔混交林>阔叶林>针叶林;灌木层为针阔混交林>针叶林>常绿阔叶林>灌草丛;草本层为针阔混交林>常绿阔叶林>针叶林>灌草丛。单因素方差分析,乔木层丰富度、多样性、均匀度在针阔混交林和针叶林呈显著性差异(P<0.05);灌木层和草本层多样性在针阔混交林与灌草丛和常绿阔叶林呈显著性差异(P<0.05)。平潭岛群落物种多样性水平明显低于普陀山岛和大陆。

Taking the natural secondary forest in Pingtan Island as the research object,this paper analyzed the changes of species composition,important value and species diversity of shrub-grass,coniferous forest,mixed wood and broadleaf forest and discussed community species diversity differences among Pingtan Island and surrounding islands and land areas.The results showed that there were 53 families,89 genera and 104 species in the four forest.Margalef index,Shannon-Wiener index and Pielou index of the community types and the various levels showed an upward trend from shrub-grass to mixed wood,and a downward trend in broadleaf forest.The change of Margalef index,Shannon-Wiener index at the various levels was as follows:tree layer was mixed wood>broadleaf forest>coniferous forest,shrub layer was mixed wood>coniferous forest>broadleaf forest>shrub-grass,and herb layer was mixed wood>broadleaf forest>coniferous forest>shrub-grass.In one-way anova,the Margalef index,Shannon-Wiener index and Pielou index of the tree layer were significantly different between mixed wood and coniferous forests(P<0.05).Shannon-Wiener index of shrub layer and herb layer was significantly different between mixed wood and shrub-grass,broadleaf forest(P<0.05).The species diversity level of Pingtan Island is significantly lower than that of Putuoshan Island and the land areas.