Abstract: The paper discussed Arctic-Tertiary dispersal and its impact on flora of Himalayan-Hengduan Mountains since the Tertiary climatic vicissitude of Arctic regions. Through analyzing distribution patterns of Rhododendron, Acer, Salix, Betula,Alnus and some genera of Saxifragaceae, Triosteum showed there were quite a few groups of flora from Himalayan-Hengduant role on the flora development of the region.In addition, the two main pathways for the migration of the flora between the arctic regions and the Himalayandition, the two main pathways for the migration of the flora between the arctic regions and the Himalayan-Hengduan Mountains were suggested, one is Himalayan-Hengduan Mountain-Qinling-NE China.

Key words: Himalayas

摘要： 通过古植物学及古地史资料,论述了北极地区在第三纪早期气候变迁对喜马拉雅-横断山地区植物区系形成的影响,并通过一些喜马拉雅-横断山地区的特征类群:杜鹃属,槭树属,柳属,桦木属和桤木属以及一些草本类群虎耳草科的落新妇族,金腰属和虎耳草属,忍冬科的莛子镳属的分布式样和起源分化的分析,说明了喜马拉雅-横断山区系中有相当一部分是这些北方起源的,北极-第三纪成分迁移是现代喜马拉雅-横断山植物区系成分的一个重要来源.并且讨论了喜马拉雅-横断山植物区系同北方植物区系可能的迁移路线,指出西南-秦岭-东北通道即西南沿四川盆地经秦岭和黄河至东北和西伯利亚和中亚高地通道即向西经帕米尔高原同北方交流,向东经西南-秦岭-东北通道迁移交流是喜马拉雅-横断山植物区系成分同北方交流的主要路线.由于第四纪冰期间冰期反复作用,各类成分在该地区保存、汇集、分化发展,使得该喜马拉雅-横断山地区成了北极-第三纪中心消失以后,在近代形成的温带和高山植物区系新的发展和分化中心.

关键词: 喜马拉雅, 横断山, 北极-第三纪成分, 高山植物区系