鼎湖山南亚热带常绿阔叶林不同树种存活对邻体组成的响应差异

doi:10.17520/biods.2018056

生物多样性 ›› 2018, Vol. 26 ›› Issue (6): 535-544. DOI: 10.17520/biods.2018056 cstr: 32101.14.biods.2018056

• 研究报告: 植物多样性 • 下一篇

鼎湖山南亚热带常绿阔叶林不同树种存活对邻体组成的响应差异

马钦洪^1,^2,³, 李艳朋^1,^2,³, 练琚愉^1,², 叶万辉^1,^2,^*()

1 中国科学院华南植物园退化生态系统植被恢复与管理重点实验室, 广州 510650
2 中国科学院华南植物园广东省应用植物学重点实验室, 广州 510650
3 中国科学院大学, 北京 100049

收稿日期:2018-02-12 接受日期:2018-04-02 出版日期:2018-06-20 发布日期:2018-09-11
通讯作者: 叶万辉
作者简介:# 共同第一作者
基金资助:
国家自然科学基金(41371078)、中国科学院B类先导科技专项培育项目(XDPB0203)和中国森林生物多样性监测网络建设项目

Difference in survival response of tree species to neighborhood crowding in a lower subtropical evergreen broad-leaved forest of Dinghushan

Qinhong Ma^1,^2,³, Yanpeng Li^1,^2,³, Juyu Lian^1,², Wanhui Ye^1,^2,^*()

1 Key Laboratory of Vegetation Restoration and Management of Degraded Ecosystems, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650
2 Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650
3 University of Chinese Academy of Sciences, Beijing 100049

Received:2018-02-12 Accepted:2018-04-02 Online:2018-06-20 Published:2018-09-11
Contact: Ye Wanhui
About author:# Co-first authors

摘要/Abstract

摘要：

理解群落结构和动态的主导机制是生态学研究的基本目标之一。群落内树种的存活受到其邻近树木的显著影响。为探究不同树种的存活对邻体组成的响应差异, 本研究基于鼎湖山南亚热带阔叶林20 ha森林动态监测样地中常见的90个树种的存活监测数据和功能性状数据, 建立了一系列关于邻体效应的树种存活模型。结果表明: 约58%的树种存活对邻体组成有敏感的响应, 共存树种间的功能性状差异影响着50%的树种存活动态。不同树种对邻体组成的响应差异与其耐阴性相关, 耐阴能力较弱的树种更倾向于表现出对邻体的敏感性。低比叶面积、高叶干物质含量、木材密度和最大胸径意味着较强的耐阴能力, 与光资源利用策略有关的生态位分化可能是邻域尺度上物种共存的原因。本研究为量化邻体间的相互作用和解释局域群落的物种共存提供了新的视角。

关键词: 邻体组成, 存活响应, 性状差异, 功能性状, 耐阴性

Abstract

Identifying the mechanisms that drive community structure and dynamics is one of the most fundamental goals in ecology. The local neighborhood in which trees grow significantly influences species survival. In order to understand the mechanisms underlying the various survival responses to neighborhood crowding among species, we compared the survival responses of focal tree species through modeling tree survival in terms of neighborhood effects. These effects were quantified in different ways, based on the survival monitoring and functional trait data of 90 species commonly observed in a lower tropical evergreen broad-leaved forest 20-ha plot in the Dinghu Mountains. We found that among all species tested, 58% showed sensitivity to neighborhood effects and that the survival response of 50% were mediated by functional trait differences among co-occurring species. Shade tolerance of species is associated with species sensitivity to its neighborhood as species with lower shade tolerance are intended to be sensitive to their neighbors. Lower specific leaf area, higher leaf dry matter content, wood density and maximum diameter at breast height indicate higher shade tolerance. Niche difference associated with light acquisition strategies may underlie species coexistence at the neighborhood scale. Our study provides new insights into quantifying neighborhood interaction and species coexistence at the local neighborhood scale.

Key words: neighborhood crowding, survival response, trait difference, functional trait, shade tolerance

马钦洪, 李艳朋, 练琚愉, 叶万辉 (2018) 鼎湖山南亚热带常绿阔叶林不同树种存活对邻体组成的响应差异. 生物多样性, 26, 535-544. DOI: 10.17520/biods.2018056.

Qinhong Ma, Yanpeng Li, Juyu Lian, Wanhui Ye (2018) Difference in survival response of tree species to neighborhood crowding in a lower subtropical evergreen broad-leaved forest of Dinghushan. Biodiversity Science, 26, 535-544. DOI: 10.17520/biods.2018056.

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链接本文: https://www.biodiversity-science.net/CN/10.17520/biods.2018056

https://www.biodiversity-science.net/CN/Y2018/V26/I6/535

图/表 5

表1 功能性状在PCA分析中各主成分(PC)的载荷值

Table 1 Factor loadings of the principal components of the PCA on functional traits

功能性状 Functional trait	PC1	PC2	PC3	PC4
比叶面积 Specific leaf area	0.582	-0.062	0.088	0.237
叶干物质含量 Leaf dry matter content	-0.367	0.489	-0.059	-0.178
叶面积 Leaf area	0.289	-0.378	-0.558	-0.337
叶片厚度 Leaf thickness	-0.366	-0.512	-0.273	-0.282
叶绿素含量 Chlorophyll concentration	-0.339	-0.324	-0.177	0.816
木材密度 Wood density	-0.422	-0.201	0.367	-0.196
最大胸径 Maximum diameter at breast height	-0.126	0.455	-0.66	0.121
累计解释量 Cumulative interpretation (%)	33.2	56.6	71.7	82.1

表2 90个目标树种对存活候选模型的选择

Table 2 Selection of models on survival for 90 species

模型 Model		合计 Total	绝对差异 Absolute difference	等级差异 Hierarchical difference
基本模型 Basic model		38	NA	NA
邻体等价模型 Neighbour equivalence model		7	NA	NA
同种密度效应模型 Onspecific density effect model		5	NA	NA
基于性状差异的模型 Models based on trait difference	比叶面积 Specific leaf area	6	6	0
	叶干物质含量 Leaf dry matter content	9	8	1
	叶面积 Leaf area	8	6	2
	叶片厚度 Leaf thickness	1	0	1
	叶绿素含量 Chlorophyll concentration	6	5	1
	木材密度 Wood density	3	0	3
	最大胸径 Maximum diameter at breast height	4	4	0
	PCA轴1 PCA axis 1	1	NA	NA
	PCA轴1-4 PCA axes 1-4	2	NA	NA
总计 Total		90	29	8

图1 对邻体组成的存活响应表现出不同敏感性的两组树种的多度分布, 其中黑色代表对邻体组成敏感的种组S, 灰色代表对邻体组成不敏感的种组IS, 虚线表示种组内物种多度的中位数。多度数据在分析前进行了对数转换。

Fig. 1 Distribution of abundance for species with different survival response sensitivity to neighborhood crowding are showed. Species sensitive to neighborhood crowding are in black while insensitive ones in grey. Median values of abundance are indicated in dashed lines. The abundance data were log transformed beforehand.

图2 对邻体组成的响应表现出不同敏感性的树种的耐阴性指数, IS和S分别表示对邻体不敏感和敏感的种组。

Fig. 2 Shade tolerance index of species with different response sensitivity to neighborhood crowding, where IS and S separately represent the species group insensitive and sensitive to neighborhood.

图3 树种耐阴性和功能性状之间的关系, A-G依次是比叶面积、叶干物质含量、叶面积、叶片厚度、叶绿素含量、木材密度和最大胸径, 其中比叶面积、叶面积和最大胸径在分析前进行了对数转换。虚线表示耐阴性指数随性状值的变化趋势。

Fig. 3 Relationship between shade tolerance index. (A) Specific leaf area (SLA); (B) Leaf dry matter content (LDMC); (C) Leaf area (LA); (D) Leaf thickness (LT); (E) Chlorophyll concentration (Chl); (F) Wood density (WD); (G) Maximum diameter at breast height (MDBH). Trends of shade tolerance index with each trait are indicated in dashed lines.

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鼎湖山南亚热带常绿阔叶林不同树种存活对邻体组成的响应差异

Difference in survival response of tree species to neighborhood crowding in a lower subtropical evergreen broad-leaved forest of Dinghushan

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