粤西次生针阔混交群落的林下植被物种组成与多样性研究

季风常绿阔叶林是南亚热带的地带性植被类型,经采伐干扰和人工造林后形成大面积的次生林。参照CTFS样地建设技术规范,于2006年在广东粤西马尾松针阔次生林建立2 hm2固定监测样地。在对样地进行调查的基础上,分析了林下植被的物种组成与多样性。结果表明：（1）样地共有维管束植物207种,隶属于79科144属,数量优势科为茜草科、大戟科、樟科、番荔枝科、紫金牛科、禾本科和蔷薇科;单种属植物较多（101属）,占总属数的70.14%。林下植物泛热带和热带亚洲成分占绝对优势,具有南亚热带向中亚热带过渡的特征。（2）物种的丰富度指数表现出乔木幼苗〉灌木层〉藤本层〉草本层;Shannon-Wiener指数表现出乔木幼苗〉藤本层〉灌木层〉草本层;Simpson指数则为乔木幼苗〉藤本层〉草本层〉灌木层;均匀度指数为乔木幼苗〉藤本层〉灌木层〉草本层。

Species Composition and Diversity of Understory Vegetation in Secondary Conifer and Broadleaf Mixed Forest in Western Guangdong Province

The monsoon evergreen broadleaved forest was the typical vegetations in subtropical South Asia,and was partly destroyed by large-scale industrial logging at the turn of the 20th century and replaced by secondary forests plantations.A long-term 2 hm^2 forest plots were established in secondary coniferous and broadleaf forest in western Guangdong following the protocols of the Center for Tropical Forest Science forest dynamic plot.Based on the sample plot investigation,the species composition and diversity was discussed.The result was：（1）There were 207 species of vascular plants belonging to 79 families and 144 genera.The dominant families of community are Rubiaceae,Euphorbiaceae,Annonaceae,Myrsinaceae,Gramineae,Rosaceae.The monotypic genera are many,101 kinds,accounting for 70.14% of the total number.Most of the floristic elements at the familial and generic level are pantropic and tropical-Asia areal types,which show some transition character of southern and mid-suhtropical elements.（2）The order of R was arbor seeding 〉shrub 〉liana 〉herb,the sequence of H was arbor seeding 〉liana〉 shrub〉 herb,D ranked from high to low was arbor seeding〉 shrub〉 herb〉 liana,and E was seeding 〉liana〉 shrub〉 herb.