中文摘要：

研究了不同扩张强度下毛竹和肿节少穗竹对江西武夷山常绿阔叶林群落结构和物种多样性的影响.结果表明：毛竹、肿节少穗竹扩张都会不同程度地改变阔叶林群落结构与物种组成,两者同时高强度扩张时（毛竹30～50 ind·100 m^-2,肿节少穗竹300～500 ind·100m^-2）,群落的乔∶灌（密度比）由2∶8变成1∶9,竹∶木（密度比）由0∶10变成9∶1.毛竹、肿节少穗竹扩张对阔叶林物种多样性影响的主效应显著,毛竹主要影响乔木层,肿节少穗竹主要影响灌木层,但两种竹子的交互作用不显著.两种竹子同时扩张对群落生物多样性的影响存在叠加效应,尤其是高强度扩张使群落Shannon指数下降91.3%.毛竹与肿节少穗竹同时低强度扩张时,两者相互影响不大,但当达到一定密度后两者会相互竞争排斥.这表明,当常绿阔叶林同时遭受毛竹、肿节少穗竹扩张时,虽然二者交互作用不明显,但会通过叠加效应影响木本植物,导致阔叶林群落简单化.

英文摘要：

The effects of Phyllostachys edulis and Oligostachyum oedogonatum expansion on species diversity of broad-leaved forests were investigated in Wuyishan National Nature Reserve,Jiangxi Province,China. Ph. edulis and/or O. oedogonatum expansion changed community structure and species composition. The co-expansion of the two bamboos in high intensity（ Ph. edulis was 30-50ind·100 m^-2,O. oedogonatum was 300-500 ind·100 m^-2） changed the density ratio of arbor and shrub from 2： 8 to 1： 9,and density ratio of bamboo and tree from 0： 10 to 9： 1. The main effects of Ph. edulis and O. oedogonatum on the species diversity were significant. Ph. edulis mainly influenced arbor layer,while O. oedogonatum influenced shrub layer more,and the interaction effect of two bamboos was not remarkable. There existed addition effects between Ph. edulis and O. oedogonatum on species diversity. The co-occurrence of two bamboos in high intensity decreased the Shannon index of community by 91.3%. Ph. edulis and O. oedogonatum did not compete obviously unless in high density. It was addition effect rather than interaction effect that changed the community structure and reduced species diversity when broad-leaved forest suffered invasion by Ph. edulis and O. oedogonatum.