湖南小溪国家级自然保护区蕨类植物区系研究

在文献和实地调查基础上,统计分析了小溪国家级自然保护区蕨类植物区系特征及其与相邻区系间的关系。结果表明:(1)该区蕨类植物丰富,共有蕨类植物34科、77属、273种(含变种),优势科为鳞毛蕨科、水龙骨科、蹄盖蕨科等5科,优势属为鳞毛蕨属、蹄盖蕨属、铁角蕨属等18属,但属内分化程度较低;(2)科和属的地理成分均以热带成分为主,说明小溪与热带联系紧密,但种的地理成分以温带性质的亚热带山地成分为主,其中尤以东亚成分中的中国—喜马拉雅型占绝对优势(占小溪总种数的38.5%);(3)在相邻6个蕨类植物区系中,物种的丰富程度由高到低依次为井冈山、梵净山、壶瓶山、小溪、八大公山、猛洞河;小溪蕨类植物区系与壶瓶山、梵净山蕨类植物区系关系密切,与八大公山、井冈山蕨类植物区系关系较为密切,与猛洞河蕨类区系关系较疏远。

The pteridophyte flora in Xiaoxi National Nature Reserve,Hunan,China

Based on statistic of its fern which got from the field investigation and reference related literature in Xiaoxi Na-tional Nature Reserve,comparatively intensive analysis on the characteristics of Pteridophyte floras and the relationship with its neighbourhood,three main conclusions were as followed:(1 )Xiaoxi National Nature Reserve is in rich in Pteri-dophyte flora and is found to have 273 species,including 77 genera in 34 families,and the dominant families are Dryopteridaceae,Polypodiaceae,Athyriaceae,etc,the main genera are Dryopteris,Athyrium,Asplenium,etc,neverthe-less,species are rare in genera;(2)The Pteridophyte flora show the tropical characteristics significantly ,based on the analysis of geographic compositions of families and genera,which indicate the close connection to the tropic,but of spe-cies,subtropical mountain compositions are dominant,notably the Sino-Himalaya (38.5%)in East-Asian elements;(3)The species richness of the nearby flora in sequence from high to low is:Jinggangshan,Fanjingshan,Hupingshan, Xiaoxi,Badagongshan,Mengdong River,and the flora of Xiaoxi is much more closely allied to Hupingshan and Fanjings-han than to the others of its neighbourhood,Jinggangshan and Badagongshan is the second,Mengdong River is the last.