【摘要】 基于路线调查和样地调查资料,鉴定记录到西藏阿里西部地区共有种子植物319种,隶属于53科159属。其中,裸子植物1科1属2种,被子植物52科158属317种,表明该地区植物种类贫乏。种子植物的区系成分复杂,划分为5个科分布区类型和9个属分布区类型,其中温带成分分布占绝对优势:温带科16科,占总科数的72.73%,温带属99属,占总属数的77.34%,说明本区系具有明显的温带性质。而热带成分仅有几个科属作为代表,表明本区系在发生发展过程中曾经历过与热带相联系的历史渊源。此外,特有性程度极低,没有中国特有科和特有属分布,证实了本区系植物的年轻性及其较短的演化发展历史。更多还原

【Abstract】 The pathway expedition and sample plot survey on seed plants in western Ngari of Tibet,China were carried out for two years from 2002 to 2003.As the result,there are 319 species of seed plants this area,which belong to 159 genera and 53 families.Among them,1 family,1 genus,2 species belong to gymnosperms,and 52 families,158 genera,317 species to angiosperm.The results show that the plant species are quite poor in western Ngari.But the types of distribution,which can be divided into 5 areal-types of families and 9 areal-types of genera,are complex.In the flora composition,the temperate elements,having 16 families and 99 genera,accounting for 72.73% in total families and 77.34% in total genera(excluding cosmopolitan),occupy a dominant position.This distribution of the flora reflects the western Ngari is obvious temperate characteristics.While the tropical elements consist of several genera and families,which indicates the flora had some connection with tropical flora historically.Moreover the flora which has no endemic to China is less dominant in endemism.It shows that the flora is not only of youthful character,but also of short evolutive history.更多还原