鄱阳湖湿地灰化苔草群落物种多度分布格局沿水分梯度的变化  

The change of species-abundance distribution patterns of Carex cinerascens community along a hydrological gradient in the Poyanghu wetland

作　　者：刘扬[1,2] 施建敏[2] 边子星 邓绍勇[3] 裘利洪[2] 张微微[2] 缪伸义 

机构地区：[1]南京林业大学林学院,江苏南京210037 [2]江西农业大学林学院,江西南昌330045 [3]江西省林业科学院,江西南昌330032

出　　处：《草业科学》2016年第1期19-26,共8页Pratacultural Science

基　　金：江西省青年科学基金(20114BAB214012);江西农业大学自然科学基金(2010-07)

摘　　要：为揭示鄱阳湖湿地苔草群落的构建机制,选择灰化苔草(Carex cinerascens)群落作为研究对象,通过设立3条样带调查不同水分梯度的群落物种多度,选用断棍模型(BSM)、生态位优先占领模型(NPM)、优势优先模型(DPM)、随机分配模型(RAM)和生态位重叠模型(ONM)5个生态位模型对群落种-多度关系进行拟合,结果表明,1)灰化苔草群落可按土壤水分划分为高湿度、中湿度和低湿度3组,分别对应从湖边、湿地中间和湿地边缘的梯度分布;2)从高到低的水分梯度上,灰化苔草群落的物种数先增加后降低,优势种多度逐渐增加,物种多度分布曲线由相对平缓变为陡峭;3)高湿度灰化苔草群落物种多度分布格局的最佳拟合模型为BSM,中、低湿度的理想模型转变为NPM。研究认为,水分条件的变化是灰化苔草群落物种多度分布格局改变的主因,随着水分梯度降低,群落构建的生态学过程由随机生态位变为生态位优先占领。研究为鄱阳湖湿地多样性保育和生态功能管理提供了理论参考。The variation of water level in Poyanghu plays a significant effect on the dominant vegetation of Carex spp.community. However,the community assemblage mechanism under the change of hydrology is unclear now. Five species-abundance distribution pattern（ SDP） models,including broken stick model（ BSM）,niche preemption model（ NPM）,dominance preemption model（ DPM）,random assortment model（ RAM） and overlapping niche model（ ONM） were employed to detect the community assemblage mechanism of C. cinerascens along a hydrological gradient in Poyanghu wetland. The results showed that the number of species firstly increased and then decreased along the hydrological gradient from high to low. Meanwhile,the curve of species-abundance distribution became steep. The optimal fitting SDP models were BSM,NPM and NPM for high humidity community,medium humidity community and low humidity community,respectively. These indicated that the hydrology condition resulted in the change of SDP. With the decrease of humidity,the community assemblage mechanisms of C. cinerascens were replaced from stochastic niche to niche preemption.

关 键 词：鄱阳湖湿地 灰化苔草 水分梯度 多度格局 生态位模型 

分 类 号：Q948[生物学—植物学]