西双版纳热带山地常绿阔叶林蕨类植物多样性研究

Species diversity of pteridophytes of tropical montane evergreen broad-leaved forest in Xishuangbanna

关键词:  蕨类植物  α-多样性  β-多样性  热带山地常绿阔叶林  西双版纳

Key words:  pteridophytes  α-diversity  β-diversity  tropical montane evergreen broad-leaved forest  Xishuangbanna

摘要:

基于4个50 m×50 m(包含400个5 m×5 m)样方调查,统计了蕨类植物的α多样性指数、优势度指数、相似性指数及β多样性指数。结果表明:在调查的1 hm²西双版纳热带山地常绿阔叶林里,蕨类植物的物种丰富度为32种; 不同样地蕨类植物丰富度指数、多样性指数、优势度指数及均匀度指数的变化趋势一致; 该森林群落蕨类植物的物种多样性虽然不高,但优势种群显著; 通过3个无人为干扰与1个受人为干扰样地的对比分析研究看出,该类森林遭受一定程度的人为干扰后,蕨类植物物种丰富度、多样性、优势度及相似性等均显著下降,其中物种多样性的降低尤为显著,既使群落的外貌、结构等恢复至接近原始林状态,蕨类植物丰富度及多样性也难以恢复,故此,保护原始的森林植被是保护该森林蕨类植物多样性的有效措施之一。

Abstract:

Based on 4 sampling plots of 50 m×50 m(divided into 400 small plots of 5 m×5 m),α-diversity,β-diversity,Jaccard index and Simpson index of ferns of the tropical montane evergreen broad-leaved forest in Xishuangbanna were studied. It was found that there are 32 fern species in a total 1 hm² area of sampling plot in the forest. The α-diversity,β-diversity,Jaccard index and Simpson index of ferns had similar patterns in the 4 sampling plots. The dominant species are conspicuous although species diversity of ferns was relatively low in the forest. However,the diversity of ferns including the α-diversity,β-diversity,Jaccard index and Simpson index decreased with disturbance,especially the α-diversity decreased conspicuously. It was also revealed that the diversity of ferns did not significantly increase in the old secondary forest comparing with that of primitive forest of the same type. This suggests that conservation of primitive forest is of most importance for the biodiversity conservation of fern species.