国家Ⅱ级保护植物滇桐生存群落分类及物种组成特征

Classification and species composition characteristics of the living communities of Craigia yunnanensis (Tiliaceae),a second-class national protected plant

滇桐(Craigia yunnanensis)为滇桐属(Craigia)主要物种之一,由于地理分布狭窄、居群数量少、生境高度异质性、物种濒危,具有重要的科研和经济价值。为探究其天然生存群落物种组成特性及数量分类状况,以独山县滇桐天然生存群落集中分布的2个区为对象,采用TWINSPAN和PCA方法进行物种分类和排序,对其植物群落物种组成及群落数量分类进行分析。结果表明:样方内记录独山县维管植物51科80属93种,其中蕨类植物9科14属17种,被子植物42科66属76种,以樟科、鳞毛蕨科和蔷薇科植物为主。TWINSPAN将独山县滇桐天然分布区40种主要植物种划分为常山+石山楠群丛、香叶树+野扇花群丛、香叶树+石岩枫群丛、滇桐+朴树+马蓝群丛4个群丛类型;PCA物种排序可划分为4个群落类型,即马蓝+芒+青冈栎群落、滇桐+椤木石楠群落、南酸枣+石岩枫群落、野扇花+石山楠+香叶树群落,各群落内物种间存在相似的生境,以阳性、耐旱树种居多。

Craigia yunnanensis is one of the main species of Craigia.It has important scientific and economic value due to its narrow geographical distribution, small population, highly heterogeneous habitat and endangered state.In order to explore the characteristics of the species composition and quantitative classification of the natural communities of Craigia yunnanensis,two areas in Dushan County that had natural communities of Craigia yunnanensis were selected as the research objects.TWINSPAN and PCA methods were used to classify and rank the species, and then the species composition and quantitative classification of the plant communities were analyzed.The results showed that there were 93 species of vascular plants belonging to 80 genera and 51 families in Dushan County, including 17 species of pteridophytes belonging to 14 genera and 9 families, and 76 species of angiosperms belonging to 66 genera and 42 families, mainly Lauraceae, Dryopteridaceae and Rosaceae.TWINSPAN divided the 40 main plant species in the natural distribution area of Craigia yunnanensis in Dushan County into 4 association types: Dichroa febrifuga + Phoebe calcarea,Lindera communis + Sarcococca ruscifolia,Lindera communis + Mallotus repandus,and Craigia yunnanensis + Celtis sinensis + Strobilanthes japonica.PCA species ordination divided the communities into 4 types: Strobilanthes japonica + Miscanthus sinensis + Cyclobalanopsis glauca,Craigia yunnanensis + Photinia bodinieri,Choerospondias axillaris + Mallotus repandus,and Sarcococca ruscifolia + Phoebe calcarean + Lindera communis.The species in each community had similar habitats, and most of them were heliophilous and drought tolerant species.