摘要
本文运用聚类和排序的方法对安徽黟县的次生灌丛及灌草丛38个样地进行了分类。样地间的相似性计算采用了Wishart(1969年)的相似性系数公式,聚合策略用形心法,排序采用了主分量分析(PCA)。根据聚类分析的结果,38个样地分为6种群落类型,并在其中5类中找出它的区分种;这6种类型在PCA排序图上可作为分离的点集划分出来,排序也能很好地反映群落间的相互关系。聚类和排序的结果与定性分类所得出的结果基本相同,说明数量分类方法是适用于亚热带次生灌丛的分类。此外,本文还对聚类和排序在亚热带次生灌丛研究中的应用进行了讨论。
Secondary shrub thicket and shrub-grassland are widely distributed in the subtropical zone of China, and they are of important effect in producing organic matter and environmental condition in that area. This paper is a report on cluster analysis and ordination of secondary shrub thicket and shrub-grassland in Yi County of Anhui Province (30°N, 118°E), which locates in the middle subtropical zone in China. 38 sample plots were investigated. Wichart's (1969) similarity ratio formula is adopted for the calculation of similarity between releves, and centroid method is used in cluster analysis. In ordination, PCA method is used. The results of cluster analysis show that these 38 plots can be classified into 6 plant community types, and the diagnostic species are sought out of the 5 types of them. On the diagram of PCA ordination, 6 types established by cluster analysis can be drawn as discrete entities, and there are no marked overlappings of the types. So ordination can show well the correlation of releves. The results of classification by using cluster analysis and ordination are very similiar to that of the qualitative classification. It is identified that the numerical classification method is applicable to the classification of subtropical secondary shrub thicket. In addition, the application of cluster analysis and ordination method in subtropical secondary shrub thicket research is discussed.
出处
《同济大学学报（自然科学版）》
EI
CAS
CSCD
1990年第1期85-94,共10页
Journal of Tongji University:Natural Science
关键词
亚热带
次生
灌丛
聚类
排序
灌木
Subtropical belt
Secondary shrub thicket
Cluster analysis and ordination
