湖北鳞毛蕨属植物的地理分布及区系特征

Studies on the Geographical Distribution and Floristic Characteristics of the Genus of Dryopteris Adanson from Hubei,China

对湖北鳞毛蕨属植物的地理分布和区系特点进行了研究。鳞毛蕨属植物广布于世界各地 ,该属的分布和多样性中心位于中国西南部和东喜马拉雅山区 ;另一中心则位于日本 ,中国东南部和南部。鳞毛蕨属是一个自然的北温带分布属。中国有鳞毛蕨属植物 134种 (包括 7变种 ) ,西南地区 (云南、四川、贵州等 )是国产鳞毛蕨属植物分布最集中的地区。区系分析表明 :湖北鳞毛蕨属植物种类比较丰富 ,有 36种 ,主要分布于鄂西北和鄂西南山区 ,是构成湖北森林植物区系林下草本植物的主要成分之一 ;地理成分比较复杂 ,种的分析显示出以中国 -日本分布和中国特有分布为主的特点 ;与相邻省鳞毛蕨属植物区系的关系比较密切 ;

This paper deals with the geographical distribution and the floristic characteristics of the genus of Dryopteris from Hubei Province of China.Dryopteris is commonly distributed in the world.One center of distribution and diversity is in southwest China and the east Himalayan,another in Japan,southeast and south China.Dryopteris is a very natural northern temperate genus.In China,including 134 species (7 varieties),more than 80% of Dryopteris are distributed in southwest China (i.e.Yunnan,Sichuan,and Guizhou).Floristic analysis indicates that,there are 36 species of Dryopteris in Hubei,which account for 26 87% of all the species of this genus in China.They are mainly distributed in the northwest and southwest of Hubei.Dryopteris is one of the main components of the herb layer in the forests of Hubei.In Hubei the geographical elements of the species are complex.Among them,both Sino Japan and Chinese endemic elements are dominant,which account for 37 84% and 30 56% of all the species of this genus,respectively.The floristic characteristics of the east of Hubei differ greatly from those of the west.Namely, east Hubei belongs to east China flora,which shows the characteristics of the transition from warm temperate zones to subtropical zones.West Hubei belongs to the central China flora,which is abundant in species,and is closely related to the southwest China flora.The flora of Dryopteris in Hubei is closely related to its neighbor regions including Sichuan,Yunnan,Guizhou,Jiangxi and Zhejiang.And the similarity coefficients are 77 78%,70 27%,67 57%,62 16%,and 62 16%,respectively.The floristic characteristics show distinct transitional nature.It acts as a link flora between east China flora and central China flora.