浙西北天然次生林群落物种多样性研究

对浙西北地区天然次生林群落植物物种多样性特征进行了研究，测定了群落植物生长型构成以及各层次植物物种的重要值，采用多种测度方法计算了群落各层次植物物种的丰富度指数、均匀度指数和多样性指数。结果表明：（1）浙西北地区天然次生林群落各层次优势种比较明显，乔木树种以青冈为主，灌木树种以柃木和檐木占优势，草本植物则以箬竹为主；（2）该地区天然次生林群落植物物种比较丰富，乔木树种种数最多，草本植物稀少；就各层次而言，草本层物种数最多，乔木层和灌木层比较接近，各层次的均匀度指数的趋势是灌木层最高，草本层最低，乔木层居中；以多种指标计算各层次物种多样性指数结果均显示，灌木层多样性指数最高，草本层最低，尽管草本层具有最高的丰富度；（3）封育时间长、人为干扰轻的地区具有较高的物种多样性指标以及数量指标，有利于生物多样性的保护。

Plant Species Diversity of Natural Secondary Forest Community in Northwest Zhejiang

The characteristics of the plant species diversity of natural secondary forest community in the northwest Zhejiang Province were studied. The plant growth form and the importance value of the community were determined, and the richness, evenness, and species diversity index of each layer of the community were calculated with varied calculation method. The results are as follows: (1) There existed the comparatively obvious dominant species within each layer of the natural secondary forest community, with Cyclobalanopsis glauca in tree layer, Cyclobalanopsis glauca and Loropetalum chinese in shrub layer and Indocalamus tessellatus in herb layer as the dominant species. (2) The natural secondary forest community in this area had rich plant species, with the species number of arbor tree being the most and that of the herb being the least. In terms of the layer of the natural secondary forest, the herb layer had the highest richness, followed by shrub layer and tree layer with a similar richness between them. The shrub layer had the highest evenness, followed by tree layer. While the richness of the herb layer was the lowest. Also, the shrub layer had the highest species diversity index calculated with various methods. The index for herb layer was the lowest even if it had the highest richness. (3) There were higher plant species diversity index and higher quantity index in the forest community which was closed for a longer time and suffered from less human disturbance.