广东种子植物区系地理成分研究

THE FLORISTIC ANALYSIS ON THE GEOGRAPHICAL ELEMENTS OF THE SPERMATOPHYTIC FLORA FROM GUANGDONG

广东种子植物区系共有２１９科１４３４属４９８６种。其中：①热带区系成分占有较大的比例，约占非世界属的６２．３％，表明广东区系受到热带区系的强烈渗透，次之为亚热带（至亚热带山地）成分约占３２．２％，及中国特有分布占５．６％；②以单型属（７２属），单种属（５８５属）和寡种属（５６２属）占绝对优势，共占８５．０％，充分显示了广东区系的古老性和过渡性特点；③从区系组成和植被结构的特征成分来看，以华夏植物区系成分为主，包括：亚热带分布，亚热带山地分布，中国特有分布，东亚—北美间断分布，及一些亚洲热带分布中以亚热带为主的属：④在这些属中有东亚特有属１３２属，中国特有属７５属以及华南—西南—中南半岛特有属６８属等；这些属的存在毫无疑问地说明，广东区系是华夏植物区系的核心地区之一，同时也显示了热带区系与亚热带区系有着不可分隔的统一性。

The spermatophytic flora of Guangdong consists of 219 families 1434 genera and 4986 species. A detailed investigstion on the composition, characteristics of Guangdong flora are showing: (1) As with the geographical elements, severely affected by the tropic elements, Guangdong flora consists a largest proportion of tropical genera (62.3%), but they aren't dominators in the forest vegetation; next plenty of arealtypes are the subtropic (or the subtropic orographic) genera (32.2%), and the genera endemic to China (5.6%). (2) The overwhelming of monotypic genera (72),single-species genera (585) and rare-species genera (562) reveal the antiqueness andtransitiveness of the Guangdong flora. (3) In view of the analysis of typical elements,Guangdong flora mainly are the constituent of Cathaysian flora, including the subtropic distribution, subtropic orographic, endemic to China, East Asia-North Americadisjuncted, and some subtropic genera in the tropical distribution of Asia; and (4)Among them about 132 genera endemics are belonging to East Asian flora, 75 generaendemic to China, 68 endemic genera to South China─SW China─Indo─China peninsula, ect.; These abundant evidences undoubtedly indicate that Guangdong is a part ofCathaysian flora; and indicated Asia tropical and subtropical region were an unity both in the floristic composition and forest-community origin.