摘要
三峡水库消落带具有独特的周期性水淹-干旱胁迫,其地形与植物群落特征具有较强的关联性,然而两者之间的关系很少受到关注,因此探索消落带不同水淹强度下微地形与植物物种多样性及功能多样性之间的关系具有重要意义。选取受三峡水库水位变化影响的重庆开州区汉丰湖北岸乌杨坝,沿高程梯度对不同微地形下群落类型及多样性分布格局、地形因子对多样性的相对贡献进行分析。结果表明:(1)消落带不同微地形之间的植物群落类型存在显著分化;(2)不同微地形的物种多样性指数存在显著差异,其中下凹地形、凸起地形中的多样性指数显著高于崎岖斜坡及平坦地形;(3)高程I中,3种物种多样性指数和2种功能多样性指数与地形起伏度呈显著负相关;高程III-IV中,3种物种多样性指数和所有功能多样性指数与地形起伏度呈显著正相关;(4)高程、地形起伏度、微地形类别依次是影响消落带物种多样性及功能多样性最重要的三个因子,其中"高程+地形起伏度"具有最大的协同效应,证明了在消落带中,更高的环境异质性可能意味着更强的群落稳定性与恢复力。研究结果揭示了消落带植物群落类型、物种多样性及功能多样性在不同高程沿微地形的空间分布格局,可为消落带生态修复及生物多样性保护提供科学依据。
The water-level fluctuation zone of the Three Gorges Reservoir is a unique ecosystem characterized by periodic flooding and drought stress,where topography strongly influences plant community dynamics.However,the connection between microtopography and plant diversity under varying hydrological regimes has received limited attention.Therefore,it is crucial to explore the connection between microtopography and both plant species diversity and functional diversity under different flooding intensities in the water-level fluctuation zone.This study investigated the effects of microtopography on plant species and functional diversity at different flooding intensities in the Wuyangba,located on the north bank of Hanfeng Lake in Kaizhou District,Chongqing,which is affected by the changing water level of the Three Gorges Reservoir.We analyzed community composition,patterns of diversity distribution along elevation gradients,and the relative contributions of topographic factors to diversity indices.The results indicated that:(1)plant community types significantly differed across microtopographic features;(2)significant differences were observed in species diversity index among different microtopographies,with the diversity index in concave and convex terrains being significantly higher than that in rugged slopes and flat terrains;(3)at elevation I,three species diversity indices and two functional diversity indices were significantly negatively correlated with topographic standard deviation(TSD);conversely,at elevations III and IV,the three species diversity indices and all functional diversity indices were significantly positively correlated with TSD;(4)elevation,TSD,and microtopography were the primary drivers of diversity,with the"elevation+TSD"combination having the strongest synergistic effect(R2=0.83,P<0.001).These findings suggest that environmental heterogeneity enhances community stability and resilience in the zone.This study provides critical insights into the spatial distribution patterns of plant communities and their diversity across microtopographies,offering a scientific foundation for ecological restoration and biodiversity conservation in the water-level fluctuation zone.
作者
程莅登
袁兴中
杨柳青
黄亚洲
魏丽锦
CHENG Lideng;YUAN Xingzhong;YANG Liuqing;HUANG Yazhou;WEI Lijin(Faculty of Architecture and Urban Planning,Chongqing University,Chongqing 400044,China;Research Center for Ecological Restoration and Control of Water Level Fluctuating Zone in the Three Gorges Reservoir,Chongqing University,Chongqing 400044,China;Nature Reserve Administration Center of Kaizhou District,Chongqing 405400,China)
出处
《生态学报》
北大核心
2025年第15期7455-7469,共15页
Acta Ecologica Sinica
基金
国家自然科学基金重点项目(52238003)
国家自然科学基金面上项目(52178031)
中央高校基本科研业务费(2021CDJQYJC005)。
关键词
消落带
水淹强度
微地形
地形起伏度
物种多样性
功能多样性
三峡水库
water-level fluctuation zone
flooded intensity
microtopography
topographic standard deviation
biodiversity
functional diversity
Three Gorges Reservoir
