林冠结构是局域尺度木本植物功能性状beta多样性形成的重要驱动力  

Canopy structure is an important factor driving local-scale woody plant functional beta diversity

作　　者：周昌艳 王彬 邓云[1,2,4] 乌俊杰 曹敏 林露湘[1,4] Changyan Zhou;Bin Wang;Yun Deng;Junjie Wu;Min Cao;Luxiang Lin(CAS Key Laboratory of Tropical Forest Ecology,Xishuangbanna Tropical Botanical Garden,Chinese Academy of Sciences,Kunming 650223;University of Chinese Academy of Sciences,Beijing 100049;School of Ecology and Environmental Sciences&Yunnan Key Laboratory for Plateau Mountain Ecology and Restoration of Degraded Environments,Yunnan University,Kunming 650091;National Forest Ecosystem Research Station at Xishuangbanna,Mengla,Junnan 666303;College of Agriculture and Biology,Dali University,Dali,Yunnan 671003)

机构地区：[1]中国科学院西双版纳热带植物园热带森林生态学重点实验室,昆明650223 [2]中国科学院大学,北京100049 [3]云南大学生态学与环境学院暨云南省高原山地生态与退化环境修复重点实验室,昆明650091 [4]云南西双版纳森林生态系统国家野外科学观测研究站,云南励腊666303 [5]大理大学农学与生物科学学院,云南大理671003

出　　处：《生物多样性》2020年第12期1546-1557,共12页Biodiversity Science

基　　金：国家重点研发计划(2016YFC0500202)。

摘　　要：功能性状beta多样性反映了群落间功能性状组成的差异,解析其形成机制是群落生态学研究的核心内容之一。本研究以云南西双版纳热带季节雨林20 ha动态监测样地为研究对象,测定木本植物11个重要的功能性状,采用多度加权的平均最近邻体性状距离度量不同取样尺度的功能性状beta多样性,基于距离矩阵的多元回归方法解析林冠结构差异、环境异质性、空间距离在功能性状beta多样性格局形成中的相对作用。结果表明,对于所有木本植物个体(DBH≥1 cm)而言,同时考虑林冠结构、环境和空间距离的模型为解释功能性状beta多样性格局的最优模型;在3个不同取样尺度上,林冠结构差异和环境距离都对功能性状beta多样性具有较大的解释力,且随着取样尺度的增大而上升,空间距离的作用基本可以忽略。本研究证实了林冠结构是局域尺度木本植物功能性状beta多样性格局形成的重要驱动力,这一发现更新了环境异质性和空间距离是驱动功能性状beta多样性格局形成的主要因素的传统认知,为将来研究功能性状beta多样性形成机制提供新的视角,并证实了取样尺度在解析木本植物功能性状beta多样性格局形成机制中的重要性。Functional beta diversity refers to the variation of functional composition between communities.Exploring the mechanisms underlying functional beta diversity is a central theme in community ecology.We measured 11 important functional traits of woody plants in 20 ha forest dynamics plot in Xishuangbanna tropical seasonal rainforest and used abundance-weighted mean nearest neighbor trait distance to quantify the functional beta diversity at different sampling scales.We revealed the relative importance of canopy structure,environmental heterogeneity,and spatial distance on functional beta diversity using multiple regressions on distance matrices.Our results showed that,for all woody plant individuals with DBH≥1 cm,the best model to explain the functional beta diversity was one including canopy structure,environment,and spatial distance.At each of the three sampling scales,canopy structure and environment had relatively large explanatory power and increased with increasing sampling scale,while the relative importance of spatial distance was negligible.Our findings corroborate that environmental heterogeneity and spatial distance are the two main factors driving functional beta diversity,and we provide new mechanistic insights by including the effects of canopy cover at local scales.

关 键 词：环境异质性 空间距离 热带季节雨林 森林动态监测样地 西双版纳 

分 类 号：S718.5[农业科学—林学]