凤阳山白豆杉种群结构及群落特性的研究

对凤阳山自然保护区白豆杉（Pseudotaxus chienii）种群大小级结构、分布格局及群落特性进行了研究.结果表明,白豆杉种群在福建柏 猴头杜鹃林及猴头杜鹃矮林中生长最为良好，其重要值分别可达5%～10%.在猴头杜鹃矮林中，大小级为增长型，存活曲线为Deevy-Ⅰ型，种群将得到长期发展；在福建柏 猴头杜鹃林中，大小级为衰退型，存活曲线为Deevy-Ⅲ型，但由于幼苗储备量较为丰富，在一定时期内还将保持稳定，在这两种群落类型中，种群呈现集群分布.在常绿阔叶林中，白豆杉的重要值只有0.9%，并且种群大小级为衰退型，存活曲线为Deevy-Ⅱ型，分布格局为随机分布，说明常绿阔叶林不适合白豆杉种群的生长.通过对白豆杉和其他种群的相关分析表明，白豆杉种群与猴头杜鹃、福建柏等呈正相关，而与褐叶青冈、木荷等呈负相关.可以认为，如果凤阳山白豆杉种群的生境能够得到切实的保护，该种群就能长期存活和发展.

Population structure and community characteristics of Pseudotaxus chienii in Fengyangshan National Natural Reserve

Pseudotaxus chienii, an endemic plant in China, is one of the second grade state protection wild plants, and distributes in Fengyangshan Natural Reserve as one of its concentrative dwelling places. A survey in the region was carried out on 10 communities, which were dominated by P. chienii. The analysis on its size structure, spatial distribution pattern and community characteristics showed that the populations of P. chienii could grow in the communities dominated by Rhododendron simiarum, Fokienia hodginsii-R. simiarum, and evergreen broad-leaved forests. In R. simiarum communities, the size structure, survival curve, and overwhelming community distribution pattern of P. chienii showed a sustaining development, while in communities dominated by F. hodginsii-R. simiarum, though the size structure was declining, the survival curve was Deevy- III type. Plenty of plantlets were still existed, and the populations kept steady. Two types were considered to be the most suitable ones for P. chienii populations. The important value of P. chienii reached 5% - 10%. In evergreen broad-leaved forests, the populations of P. chienii showed to be a declining type, and the survival curve was Deevy- II type. The distribution pattern was random, indicating that P. chienii populations could not fit for survive in this kind of communities. Correlation analysis showed that P. chienii populations had a positive correlation with R. simiarum and F. hodginsii, but a negative correlation with Cyclobalanopsis stewardiana and Schima superba. P. chienii could associate to the habits with the community canopy density of about 0.6 - 0.8. From the results mentioned above, the populations of P. chienii could be able to sustain and develop, and the existing habitat in Fengyangshan should be protected effectively. The protection of P. chienii requires more basic work to establish efficient measures to protect its habitat.