梵净山种子植物区系特征及植物地理学意义

Characteristics of spermatophyte flora of Fanjing Mountain and its phytogeographical significance

关键词:  梵净山, 种子植物区系特征, 植物交汇, 植物地理学意义

Key words:  Fanjing Mountain, characteristics of spermatophyte flora, plant intersection, phytogeographical significance

摘要:

梵净山为地处云贵高原向湘西丘陵过渡斜坡区,是武陵山脉的最高主峰,面积约为77 514 hm²。该研究针对当地野生种子植物区系的问题,主要通过对种子植物科属种水平的地理成分、区系古老性、区系过渡性等区系特征进行了统计和分析。结果表明:(1)该区物种丰富、地理成分复杂,共有野生种子植物163科843属2 584种,中国特有种1 010种(含梵净山特有种46种),其中属的热带、温带地理成分比例相当,热带成分略占优势。(2)该区植物起源古老,保存有梵净山特有裸子植物梵净山冷杉、长苞铁杉、粗榧、水青树、伯乐树、领春木等大量古老树种。(3)该区与临近区系交汇、渗透现象明显、过渡性质突出,经初步确定以梵净山为典型分布边界点的植物共有120科197属288种,分别有103种、62种、87种、36种以梵净山地区为分布的北界、南界、东界和西界,即梵净山更多的阻碍了热带、亚热带植物的北迁和中国—喜马拉雅成分的东扩。(4)该区常绿树种与落叶树种并茂发育,热带成分与温带成分竞争激烈。因此,梵净山在中国植物区系甚至东亚植物区系中具有非常重要的意义。 关键词: 梵净山, 种子植物区系特征, 植物交汇, 植物地理学意义

Abstract:

Fanjing Mountain is located in the transitional slope area from the Yunnan-Guizhou Plateau to the hills of West Hunan. It is the highest main peak of wuling mountains and covering an area of about 77 514 hm². This paper reported the results of study on floristic feature of the spermatophytic flora of Fanjing Mountain region. The results were as followed:(1)The area was rich in species and complex in geographical elements. There were 2 584 species belonging to 843 genera and 163 families, in which 1 010 species were endemic to China(among them 46 species are endemic to Fanjing Mountain). The tropical geographical elements of genera was a little more than temperate zone.(2)The flora of Fanjing Mountain was rich of relict and endemic species and original taxa, e.g. Abies fanjingshanensis, Tsuga longibracteata, Cephalotaxus sinensis, Tetracentron sinense, Bretschneidera sinensis, Euptelea pleiosperma, etc.(3)The flora of Fanjing Mountain had extensive relationship with the surrounding flora. The analysis indicated that Fanjing Mountain was probably situated at a special distribution boundary, where there were 120 families 197 genera 288 species. They were the north, south, east and west boundary of 103, 62, 87 and 36 species respectively. In other words, Fanjing Mountain was the barrier that prevented many tropical and subtropical plants moving further north and also stopped many west Himalaya components moving eastward.(4)Both evergreen trees and deciduous trees had developed collectively, and tropical geographical elements and temperate geographical elements had competed strongly. Furthermore, Fanjing Mountain is an important floristic region to Chinese spermatophytic flora and East Asia flora.