图论在中国三尖杉属植物区系地理成分划分中的应用

本文根据图论中树与生成树的理论,选用中国三尖杉属(Cephalotaxus)8种植物的地理分布资料,采用图论分类法——Prim法,对国产三尖杉属植物地理分布进行定量研究。结果表明,本文应用图论分类法划分植物区系地理成分基本上是成功的,其结果与传统分析基本相符,尤其是采用不对称信息系数构成相异矩阵的方法;此外,本方法还有以下特点:(1)结果直观、简单;(2)能处理非常复杂的植物地理分布问题;(3)能避免因人为主观意识所引起的片面性甚至错误;(4)能准确地反映各类区系地理成分之间及其在地质时期植物地理联系的“亲缘关系”。

APPLICATION OF GRAPH THEORY IN DIVISION OF FLORISTIC ELEMENTS OF THE GENUS CEPHALOTAXUS IN CHINA

Based on the theories of Tree and Spanning Tree in Graph theory, this paper selects the data of the distribution of 8 species belonging to the genus Cephdotaxus in China. By means of Graph theoretical methods of classification (that is to say Prim's method in detail), the quantitative study is carried out for the distribution of 8 species belonging to the genus Cephalotaxus in China. The result shows that this paper is basically successful for the application of Graph theoretical method of classification in the division of the floristic elements of Cephalotaxus in China, and the results of this method and the classical analysis are basically unform,especially using the asymmetric information coefficients to constitute dissimilarity matrix. On the sides, Graph theoretical method of classification with its special features as follows: ( 1 ) The results of this method are very intuitive and simple; ( 2 ) This method can treat the very complex problems for the phytogeographical distribution; (3) This method can avoid the one-sided -ness even as errors that are arose from the artifical subjective consciousness; (4) This method can reflect accurately " the consanguineous relationships" among each iloristic elements and its phytogeographical relationships in the geological time.