| This study focuses on 700 vascular plant species we investigated in Thousand Island Lake region.Species were divided into groups with different functional traits in order to take part in characteristic and quantitative analysis.In the meantime,effects of plant species functional types influenced by different extent of anthropogenic disturbance were evaluated. The study provides theoretical reference for conservation of semitropical plant functional traits and biological diversity under forest fragmentation.It is also meaningful by contributing data-base on future study in Thousand Island Lake region with community ecology and island biological geography.The research mainly covers the following sections:1.Plant species investigation799 vascular plant species was detected,including 96 planting and 703 wild species. Among these,17 species belonging to 14 genera,6 families were gynmosperm,34 species belonging to 22 genera,15 families were fern,and 748 species belonging to 447 genera,122 families were angiosperm.2.Plant qualitative function traitsWe adopted six types of qualitative functional traits(growth form,life form,fruit types, leaf characteristics,shade tolerance and pollination styles) to evaluate the community structure.The results showed:among the 703 species we investigated,arbor,small tree and shrub dominated with growth form.MaPh dominated with life form.For fruit type,capsule, drupe and achene were the main types.For leaf texture,orthophyll and sclerophyll were the main types.For leaf type,simple leaf dominated.Both richness of evergreen or deciduous and entire or non-entire leaf were close.And entomophilous was the main pollination type.3.Plant quantative function traitsWe carried analysis on quantity character of the investigated plant functional traits, including specific leaf area(SLA),leaf dry mass content,leaf thickness,specific stem density and stem dry mass content.Each trait analysis of leaf and stem involved 227 and 145 species respectively.Negative correlation were detected between SLA and leaf dry mass content,SLA and leaf thickness(r =-0.610,-0.231,P＜0.01).The correlation between leaf thickness and leaf dry mass content was non-significant.We also found negative correlation between specific stem density and stem dry mass content(r = -0.21,P＜0.05).One way ANOVA analysis suggested that there was a significant difference among the grow forms groups in their specific leaf area,leaf area,and leaf dry mass content,and among six faculties groups in their specific leaf area,leaf thickness,leaf dry mass content.Average weight of seed dry mass showed arbor＞shrub＞liane＞gramineous＞non- gramineous,the result implied that seed size is related to plant's growth form.Moreover,we observed that grand plant also had heavier dry mass.One way ANOVA analysis suggested that there was a significant difference among the grow forms groups in their seed dry mass content.4.The effects of different intensity of human disturbance on the plant functional trait in islandsBy using TWINSPAN and DCA ordination analysis,all detected 138 species in 20 islands with different intensity of disturbance were divided into 5 groups.PFTsl consists species of evergreen,phaenerophyte and non-herbaceous / evergreen,chamaphytes and non-herbaceous;PFTs2 consists of deciduous,phaenerophyte and non-herbaceous / deciduous, chamaphtes,non-herbaceous;PFTs3 consists forbs,flash-fruited and fern;PFTs4 consists forbs and dry-fruited;PFTs5 consists the group of grass,fern and herbaceous-vines.The average proportions of PFTsl,PFTs3 and PFTs4 showed decline as disturbance intensity increased.This indicated that disturbance of different intensity have negative effects on plant diversity and functional structure of the three groups in some degree,in Pearson correlation analysis(r = -0.385,-0.384,-0.329;P＞0.05).While PFTs2,PFTs5 showed increase as disturbance intensity increased.Intensity below medium could promote plant diversity and functional structure of PFTs2,PFTs5.(r = 0.310,0.286;P＞0.05)...
|
PDF Full Text Request