Abstract: The paper present the characters of the vegetation in the Big Bend Gorge (600~ 2 500 m) of Yalu Tsangpo river, S.E. Tibet, E.Himalayas. The original vegetations of the region are mainly as follows; (1) tropical low mountain semi-evergreen rain forest: Ahtingia excelsa + Terminalia myriocarpa community, Ahtwia excelsa + Lagerstroemia minuticarpe community, KAItingia excelsa community. (2) Subtropical mountain evergreen broadleaved forest: Castanopsis hystrix + Altingia excelsa community; Castanopsis hystrix community; Castanopsis echidnocarpo + CycIobalanopsis gambleana + Lithocarpus xizangensis community; Quercus lodicosa + Cyclobalanopsis gambleana community and Quercus lanata community. etc.

Key words: Vegetation, Yalu Tsangpo River, E.Himalayas

摘要： 论述了喜马拉雅东部雅鲁藏布江大峡弯河谷地区（即海拔 600~2500 m）的植被组成特征。本地区原始植被主要有：（1）热带低山半常绿雨林：阿丁枫+千果榄仁群落，阿丁枫+小果紫薇群落，阿丁枫群落;（2）亚热带常绿阔叶林：刺拷+阿丁枫群落，刺拷群落，短刺拷+毛曼青冈+西藏石栎群落，西藏栋+毛曼青冈群落，通麦栎群落；（3）亚热带山地半常绿阔叶林：薄片青同群落，依江栋群落；（4）常绿针叶林：不丹松群落，喀西松群落。此外，本区还分布有处于次生演替各个时期的大面积的次生植被，主要有：尼泊尔桤木群落；中平树＋鸡嗉子果+尼泊尔桤木群落，常绿竹丛；野芭蕉群落；热带高草群落。

关键词: 植被, 雅鲁藏布江, 东喜马拉雅