摘要
河岸带生态系统是水生生态系统和陆生生态系统进行物质、能量和信息交换的生态交错带,具有较高水平的物种多样性并能提供多种生态系统服务。本研究基于植物群落调查,探讨了北江干流河岸带植物物种组成以及纵向环境梯度上植物物种α、β和γ多样性的分布规律。结果表明:(1)群落调查共记录植物59科116属136种,以禾本科和菊科植物居多,但样地间物种差异明显,物种出现频率低,其中只出现1次的物种数百分比高达48.7%～71.4%,表明河岸带维持植物物种多样性的功能很大程度上是维持不同的物种共存,而不是单一物种的数量;(2)在纵向环境梯度上,α多样性均呈先减少后增加的趋势,高海拔河岸带物种α多样性最高;(3)纵向环境梯度物种替代性表现出强烈的波动性和间断性,而相似性则呈现连续变化,这与河岸带保存物种多样性的特征以及人类活动、地形、气候要素等影响下物种分布相对不均有关;(4)γ多样性在纵向环境梯度上呈先减少后增加的趋势,说明河岸带γ多样性在区域尺度上受多种环境梯度交互影响,但高海拔河岸带物种γ多样性高于低海拔河岸带。
Riparian ecosystem is the ecotone between aquatic ecosystem and terrestrial ecosystem. It harbors high biodiversity and provides numerous ecosystem services.In this study,we exam- ined species composition and α,β,and γ diversities of plant communities in the riparian zone along a longitudinal gradient of elevation from downstream to upstream of the Beijiang River.The results showed that :(1)A total of 136plant species belonging to 115genera and 59families were recorded.Gramineae and Compositae were dominant families.Species composition differed among plots.Many species were found with low frequency,with 48.7%-71.4%of total species occurred only once,suggesting that riparian ecosystem maintained plant species diversity through harboring different species rather than high individuals of single species.(2)The oL diversity first decreased and then increased along the longitudinal gradient,with higher values observed at plots located in high altitudinal riparian zone.(3)Plant species turnover presented intense fluctuation and discontinuity from low altitudinal to high altitudinal sites or from downstream to upstream, while the similarity of plant species consistently varied.This would be related to the specific char- acteristics of riparian zone in maintaining biodiversity and the relative heterogeneous distribution of plants species derived by human activities,topographic,and climatic factors.(4)The γ diversity along the longitudinal gradient showed a down-up trend,suggesting that the riparian γ diversity at regional scale was simultaneously influenced by many environmental gradients.The γ diversity of high altitude was higher than that of low altitude.
作者
赵清贺
冀晓玉
丁圣彦
徐珊珊
ZHAO Qing-he;JI Xiao-yu;DING Sheng-yan;XU Shan-shan(College of Environment and Planning,Henan University,Kaifeng 475004,Henan,China)
出处
《生态学杂志》
CAS
CSCD
北大核心
2018年第12期3654-3660,共7页
Chinese Journal of Ecology
基金
国家自然科学基金项目(41301197)
河南省高等学校重点科研项目(18A170004)资助
关键词
物种多样性
梯度分析
河岸带
北江流域
species diversity
gradient analysis
riparian zone
Beijiang Basin
