云霄县巨尾桉人工林群落林下植被多样性研究

Study on Undergrowth Vegetation Diversity of Eucalyptus grandis×E.urophylla Plantation Community in Yunxiao County

为揭示云霄县巨尾桉(Eucalyptus grandis×E.urophylla)人工林群落植被分布特征,对该区巨尾桉人工林下植被组成、群落结构等进行了调查。结果表明:(1)该群落林下共记录到植物22科28属36种497株,其中,灌木22种,占61.11%;草本植物14种,占38.89%。植物群落种数最多的是禾本科,其次是蔷薇科、菝葜科;从数量上看,禾本科植物所占比重最大,为23.14%。(2)各层次重要值:灌木层中毛冬青(Ilex pubescens)的重要值最大,为29.65;其次是粉背菝葜(Smilax hypoglauca)和梅叶冬青(Ilex asprella)。草本层中蕨(Pteridium aquilinum var.latiusculum)的重要值最大,为52.49,占明显优势地位。(3)灌木层物种丰富度、Shannon-Wiener多样性指数和均匀度指数均明显高于草本层,但是Simpson优势度指数草本层大于灌木层。

To reveal the vegetation distribution characteristics of Eucalyptus grandis×E.urophylla plantation community in Yunxiao County,this study investigated the composition and community structure of undergrowth vegetation of Eucalyptus grandis×E.urophylla plantation in the area.The results showed as the following three aspects.(1)A total of 497 plants belonging to 36 species,28 genera,22 families,were recorded under the forest in the community,with 22 species of shrubs,accounting for 61.11%,14 species of herbaceous plants,accounting for 38.89%.Poaceae had the largest number of species in the plant community,followed by Rosaceae and Smilacaceae.In terms of quantity,Poaceae plants accounted for the largest proportion of 23.14%.(2)The important values at all levels were as follows:the important value of Ilex pubescens in the shrub layer was the highest of 29.65,followed by Smilax hypoglauca and Ilex asprella.The important value of Pteridium aquilinum var.latiusculum in the herb layer was the highest of 52.49,occupying a clear dominant position.(3)The species richness,Shannon-Wiener diversity index and evenness index of the shrub layer were significantly higher than those of the herb layer,but the Simpson dominance index of the herb layer was greater than that of the shrub layer.