巴颜喀拉山地区植物区系研究

The Floristic Characteristics in the Region of Bayan Har Mountains

巴颜喀拉山地区位于青海省南部 ,北纬 32°2 0′～ 35°15′ ,东经 94°5 0′～ 10 1°4 5′ ,面积约84 0 0 0km2 ,海拔高程介于 36 0 0m至 5 36 9m之间。本地区拥有种子植物 1116种 ,分属于 6 4科 ,2 95属。区系特征概述如下 :1)对属的分布区类型的分析表明 ,本地区植物区系以北温带成分为主 ,仅有 9个分布区从热带延伸到温带的热带属 ,且在本区所含种类极少或仅有 1种。 2 )对种的分布区类型的分析表明 ,大多数种 (不包括中国特有种 )属于中亚成分和东亚成分 ,且多呈中亚 -喜马拉雅 -中国西南或中国 -喜马拉雅分布式样。以此为据所得结论是 ,本地区的种以温带成分为优势 ,具高原、高山分布的特点。 3)本区东南部的生态环境和区系成分的来源均不同于其余地区。东亚分布型及其变型中国 -喜马拉雅的种聚集在东南部。这里被认为是那些来源于横断山和西秦岭的区系成分的一个通道。 4 )对中国特有种的分析表明 ,本区系与横断山区系和甘肃南部区系联系最为密切。 5 )在高山特化作用和高山生态因子的选择之下 ,本区植物获得了适应寒冷和干旱的特性。 6 )本区植物的耐寒性常常伴随着耐旱和耐湿的双重特性 ,植物的这些特性也反映在它们的地理分布上。 7)本区的区系性质和特点与唐古特地区基本一致 。

Bayan Har Mountain which owns a land area about 84 000?km^2 and a height range above sea level from 3 600-5 369?m,is located at S.Qinghai between 32°20′-35°15′ N and 94°50′-101°45′ E.There are 1 116 species of seed plants belonging to 46 families and 295 genera in this area.The floristic characteristics are summarized as follows: 1)Analysis of the generic distribution pattern demonstrated that they mainly consist of north temperate elements,except 9 genera which have a distribution from tropical to temperate zone and only a few or one species of them were found in this area. 2)Analysis of the specific distribution pattern demonstrated that most of the species (excluded those endemic to China) belong to C.Asia and E.Asia elements especially to those with distribution from C.Asia to both Himalaya and S.W.China or Sino-Himalaya.By the evidence mentioned above,it easily comes to a conclusion that the species belonging to temperate elements had achieved complete dominance in this area and always distributed in plateau and alpine mountains. 3)In the southeast of this area,the ecological environment and the source of floristic elements differ from the others.The species from E.Asia and its subtype Sino-Himalaya concentratively collected at this place.It should be regarded as a corridor of the floristic elements from Hengduan Moutains and W.Qinling Mountains. 4)Analysis of the endemic species from China demonstrated that the flora is most closely related to those of Hengduan Mountains and S.Kansu. 5)The species under alpine specialization and selection of the alpine ecological factors obtained the adaptive characters to resist the frigidity and the aridity. 6)The plants with cold-resistance are always accompanied with dual species abilities of drought-tolerance and wet-tolerance.These characters of the plants are also reflected in their distribution. 7)The floristic nature and characteristics basically are in accord with those of Tangut area,in other words,it is only a part of Tangut flora.