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作 者 ：吴玉虎

期 刊 ：武汉植物学研究 2009年 27卷 3期 页码：277-289

关键词：澜沧江源区；植物区系；区系特征；区系分区；

Keywords:The source area of Lancangjiang(Mekong River), Flora, Floristic characteristics, Floristic regionalization,

摘 要 ：澜沧江源区位于青海省的南部,约处于北纬31°30′～33°53′,东经92°35′～97°35′.海拔3500～5900 m,面积约50590 kmp>2p>,属于高原大陆性气候类型.本区共有野生种子植物61科、279属、996种.分别占青海省总科数的67.78%、总属数的54.92%、总种数的43.59%.区系特征如下:(1)种类相对丰富,木本较少;(2)就属的层面而言,本区属于以北温带成分,特别是欧亚大陆温、寒地带典型成分和东亚的中国-喜马拉雅高山成分为优势的高寒类型的温带区系性质;(3)许多属和多数种均以横断山地区和西藏东北部高原为传播通道而与喜马拉雅关系密切;(4)为青藏高原主体区系与横断山区系的交汇过渡区,区系的过渡性质明显;(5)是青藏高原植物亚区唐古特地区的一部分;(6)是青海植物区系或"唐古特植物地区"中植物分化比较活跃的地区之一.

Abstract:The source area of Lancangjiang(Mekong River)is situated in the south of Qinghai,China,between latitude 31°30′～33°53′N and longitude 92°35′～97°35′E.The area at an altitudinal range of 3500 m to 5900 m.,with c.50590 km² in total area.Its climate is plateau-continental one.There are 996 species of native seed plants which belong to 61 families and 279 genera in the area.They are 43.59% of the total species and 54.92% of the total genera,67.78% of the total families in Qinghai,respectively.The floristic characteristics in native seed plants for the area are as follows:(1) Number of species are relatively rich and woody ones are poor.(2) At generic level,the flora is temperate in nature,dominated by North Temperate elements especially the typical ones from the warm and cold zone of Eurasia and the Alpine from Sino-Himalayan elements of the E.Asia.(3) Many genera and species come from the Heng-duan Mt.and the northeast plateau of Tibet are closely related to these of the Himalaya.(4) Floristic-geographically,it is a convergent and transitional region for the Qinghai-Tibetan Plateau Alpine Flora and the Hengduan Mt.Flora.The transitional nature of the flora is conspicuously.(5) It is a part of the Tangute Flora.(6) Floristically,it is one of the most active differentiate area in the flora of Qinghai or in the Tangute Area.

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