云南蕨类植物的物种多样性和区系组成

在一定实地调查和分类的基础上,采用统计分析及区系地理分析法,对云南地区蕨类植物进行研究。结果表明:云南地区共有蕨类植物60科193属1 530种(包括变种和变型),科、属、种分别占中国蕨类植物科总数的58.8%,属的83.9%和种的95.2%;在这60个科中含30种以上的有13个,含5个属以上的有11个,分别占该蕨类植物区系属、种数的56.5%和79.2%,特别是鳞毛蕨科、蹄盖蕨科、水龙骨科和金星蕨科,这4个科共拥有70属761种,分别占总属数、总种数的36.3%、49.7%;193属中含30种以上的有11个,分别占总属、总种数的5.7%和41.7%,最具优势的是鳞毛蕨属和耳蕨属、蹄盖蕨属、铁角蕨属、卷柏属,这5个属共有403种,占总种数的26.3%;该区系中无云南特有科,但具有4个亚洲特有科:雨蕨科、稀子蕨科、柄盖蕨科和骨碎补科;该区系以热带、亚热带性质为主,科的区系成分中热带亚热带分布的科占66.6%,热带成分的属有112个,占68.7%(除世界分布类型);该区系是东亚地区蕨类植物区系的重要组成部分,东亚分布31属和中国特有分布6属,分别占总属数(除世界分布属外)的19.0%和3.7%;该地区蕨类植物区系与西藏、台湾具有共同的区系起源和物种分化形成的背景,属的相似性系数约为70%,种的相似性系数约为30%,均起源于热带亚热带地区;属的热带区系成分与温带区系成分所占比例分别为68.7%和27.6%,存在一定的区系过渡性;该区系科的分化强度为3.2,属的分化强度为7.9,在科、属水平上均表现出较强的区系分化特征。

Species diversity and floristic composition of the fern flora of Yunnan, China

Based on the field investigation and plant classification, the floristic analysis of fern in Yunnan Province was studied. We made Flora of Yunnan(Vol. 20 and Vol. 21)complete,which was the principal research material,by using the list of local ferns in Mt. Ailaoshan Nature Reserve,Xishuangbanna,Yuengling Nature Reserve,Dulong River and so on supplementing the list of pteridophyte in Yunnan,through routine method of statistical analysis method and the analysis of the floristic geography study of ferns in Yunnan,in order to find out the number of species in Yunnan ferns,the floristic composition characteristics and contact area of the surrounding area. The results were as follows:The fern flora of Yunnan consisted of 60 families,193 genera and 1 530 species(including varieties and forms),and the family,genera and species accounting for the total number of ferns in Chinese were 58.8%,83.9% and 95.2% respectively; The number of families containing more than 30 species was 13 and the number of families containing more than 5 genera was 11 in this 60 families, these genera and species accounting for the total number of ferns in Yunnan Province was 56.5% and 79.2%, especially the Dryopteridaceae, Athyriaceae, Polypodiaceae, thelypteridaceae, there were 761 species of ferns belonging to 70 genera in 4 families, accounted for 36.3% and 49.7% respectively,the number of genera containing more than 30 species was 11,accounted for 5.7% and 41.7% respectively,and the dominant genera were Dryopteris,Polystichum,Athyrium,Asplenium,Selaginella,the five genera had 403 species which accounted for 26.3% of the total species in this area; the peteridophyte florae did not contain the families endemic in Yunnan Province,but had four endemic families in Asia: Peranemaceae,Monachosoraceae,Davalliaceae,Gymnogrammitidaceae; The floristic analyses showed that the main elements were tropical and subtropical in nature, the families in tropical and subtropical distributions accounted for 66.6% in the family areal type and the tropical distribution type had 112 genera,which accounted for 68.7% of the total genera(excluding the Cosmopolitan); The fern flora of Yunnan was an important part of East Asia,there were 31 genera distributed in East Asia and 6 genera in China alone,respectively accounted for 19.0% and 3.7% of the total genera in addition to the cosmopolitan; The fern floras of Yunnan,Tibet and Taiwan,China shared common floristic elements,and origin,as well as the background of species differentiation,the similarity coefficient of genera was about 70% and the similarity coefficient of species was about 30%,their common originated in tropical and subtropical areas; At the genus level,tropical floristic composition accounted for 68.7%,temperate floristic elements 27.6%,there was a certain degree of floristic transition; The intensity of floristic differentiation at family level was 3.2 and at genus level was 7.9. The flora differentiations both at family and genus levels are strong.