湖北京山对节白蜡自然保护区种子植物区系研究

Study on Spermatophyte flora of Fraxinus hupehensis Nature Reserve in Jingshan county of Hubei

通过对京山对节白蜡自然保护区进行野外调查及文献检索,分析其植物物种组成和区系地理成分。结果显示:保护区共有种子植物133科496属939种。区系组成中,在科的层次上,Compositae为保护区内含植物种类数最多的科;在属的层次上,Polygonum为含植物种数最多的属,种的层次上,Fraxinus hupehensis为保护区内绝对优势植物,分布范围极其广泛,从保护区的最低海拔到最高海拔均有分布,并多区域形成群落。初步探讨了该地区植物区系的性质:区系成分具有复杂性和多样性,拥有中国种子植物分布区类型科级水平的12个类型,属级水平的15个类型,各类热带成分共164属,占总属数的37.44%;各类温带分布类型(不包括中国特有分布)共264属,占总属数的60.27%,植物区系偏重于温带性质,具有亚热带向温带过渡的特点。保护区内特有性较突出,有中国特有分布有10属,特别是大洪山南麓区域特有种—Fraxinus hupehensis分布范围极其狭窄,仅分布于京山县和钟祥市接壤的大洪山余脉伸入部分形成的低山高丘类型地区。

By scientific survey and analysis of historical data, we find that spermatophyte in Fraxinus hupehensis nature reserve in Jiangshan county consist of 939 species which belong to 496 genus and 133 families. Based on the analysis of the floristic elements from the level of genera and family. We find that： On the family level, Compositae contains the largest number of plant species;On the genus level, Polgonum contains the largest number of plant species; On the species level, Fraxinus hupehensis is the plant having the absolute advantage, and distributed widely from the lowest altitude to the highest altitude, and forms communities in multi--regions. The flora compositions are complicated and various in the re- serve, with 12 types of the family level and 15 types of the genus level of Chinese spermatophyte distribution area. Tropi- cal genus account for 37.44% of total genus, and temperate genus represent 60.27%, which reveal the flora is temperate and has the transition characteristics from subtropical to temperate. The endemism is outstanding with 10 endemic genus of China. The distribution scope of Fraxinus hupehensis, which is regional endemic species, is very narrow; and it only distributes in Jingshan county and Zhongxiang city.