Habitat Association Of Lianas In A Subtropical Forest Of Kanghe Nature Reserve

Liana,an essential feature distinguishing tropical and subtropical forests from temperate forests,is one of the most important components of tropical and subtropical forests,accounting for 25% up to 44% of woody plant species richness.Thus,study on liana diversity patterns can help us to know species diversity in tropical and subtropical forests.So far,the studies on species diversity of subtropical evergreen broadleaved forests are much fewer than those of tropical rain forests.Meanwhile,most of the studies on habitats focused on the tree and shrub layers.Due to the difficulty of field work,the relationship between liana diversity and habitat remains largely under studied.In this paper,the species composition and structural characteristics of liana community were studied in a 2-ha permanent sample plot established in a subtropical evergreen broadleaved forest in Kanghe Nature Reserve.Habitat associations in the liana community were also investigated.The study aimed to provide reference for the related research of liana and habitat and scientific basis for the maintenance of forest diversity and the sustainable development of ecosystems.The 2-ha sample plot was divided into fifty 20 m320 m plots for convenient survey of the habitat factors and liana communities.We recorded 1463 liana individuals with DBH?1cmfrom 30 species,22 genera and 19 families.The dominant species were Millettia dielsiana,Actinidia latifolia,Cryptolepis sinensis and Rourea microphylla.The most abundant genera of were Actinidia,Rourea,Millettia.Spearman's rank correlation analysis and canonical correspondence analysis(CCA)were used to explore the correlations between Liana community and habitat factors.The results of CCA ordination showed that tree species richness,altitude,and total potassium in soil had significant effects on the liana community.Indicator species analysis showed that Ecdysanthera rosea could be used as an indicator of 5 habitat factors,and its indicator values were generally higher than other indicators.However,these species only occurred in a special range of each habitat factor,indicating that some species more frequently appeared in a certain environmental condition.Spearman's rank correlation analysis showed that exchangeable manganese,total phosphorus,soil bulk density,exchangeable magnesium were significantly and positively correlated with liana species richness,diversity index,total basal area.Moreover,these four factors were also significantly and positively correlated with number of individuals of lianas.The quantitative structure,diversity of lianas were significantly and positively correlated with tree species richness,but significantly and negatively correlated with tree total basal area.Results of Spearman's rank correlation analyses showed a significantly positive correlation between liana diversity index and the Shannon Wiener index of tree,a significantly negative correlation between number of individuals of lianas and tree DBH,and no significant correction between liana and understory light.The diversity of lianas was significantly and negatively correlated with elevation.