南亚热带森林常见种和偶见种的功能多样性特征

群落特征可能取决于物种在功能实体功能特征的独特组合（FE）中的分布。了解这些分布是保护生物多样性和维持生态系统功能的基础。鼎湖山南亚热带常绿阔叶林群落物种丰富,根据物种的多度来区分常见种（每hm²超过一个个体）和偶见种（每hm²少于一个个体）。基于功能实体,分别计算功能实体数量、功能冗余度、功能脆弱度和功能过度冗余度来描述每个样方中常见种和偶见种的功能多样性。采用Wilcoxon检验检测常见种和偶见种功能性状的差异,通过线性回归分析常见种和偶见种的功能多样性与物种数量的关系,采用冗余分析（RDA）影响常见种和偶见种的功能多样性的环境因子。研究结果表明：（1）鼎湖山南亚热带常绿阔叶林群落中功能性状在常见种和偶见种间差异显著。（2）群落中数量较低的偶见种保持着较高比例的功能实体数量。功能实体数量、功能冗余度与常见种和偶见种数量显著正相关,功能过度冗余度与偶见种数量显著正相关,功能脆弱度与常见种和偶见种的物种数量呈显著负相关。（3）海拔是影响常见种功能多样性最关键的地形因子,凹凸度是影响偶见种功能多样性最关键的地形因子。土壤含水量是影响常见种功能多样性最关键的土壤因子,速效钾是影响偶见种功能多样性最关键的环境因子。研究结果表明,尽管物种丰富的热带森林具有较高的功能冗余,但其提供的保险效应不能抵消生态系统的功能脆弱性。减少具有独特功能实体和偶见种的损失是避免热带森林生态系统功能损失的有效和必要的方法。     

Unraveling the relative contribution of inter‐ and intrapopulation functional variability in wild populations of a tadpole species

Functional traits are increasingly recognized as an integrative approach by ecologists to quantify a key facet of biodiversity. And these traits are primarily expressed as species means in previous studies, based on the assumption that the effects of intraspecific variability can be overridden by interspecific variability when studying functional ecology at the community level. However, given that intraspecific variability could also have important effects on community dynamics and ecosystem functioning, empirical studies are needed to investigate the importance of intraspecific variability in functional traits. In this study, 256 Scutiger boulengeri tadpole individuals from four different populations are used to quantify the functional difference between populations within a species, and the relative contribution of inter‐ and intrapopulation variability in functional traits. Our results demonstrate that these four populations differ significantly in functional attributes (i.e., functional position, functional richness, and low functional overlap), indicating that individuals from different populations within a species should be explicitly accounted for in functional studies. We also find similar relative contribution of inter‐ (~56%) and intrapopulation (~44%) variation to the total variability between individuals, providing evidence that individuals within populations should also be incorporated in functional studies. Overall, our results support the recent claims that intraspecific variability cannot be ignored, as well as the general idea of “individual level” research in functional ecology.     

水盐变化对荒漠植物功能多样性与物种多样性关系的影响

研究植物功能多样性与物种多样性关系对土壤水盐环境的响应规律,有助于掌握胁迫环境下植物多样性的维持机理.本研究分析了艾比湖高、低土壤水盐环境下荒漠植物功能多样性、物种多样性差异及二者间关系在不同水盐环境下的变化规律.结果表明:(1)高水盐环境下植物功能离散度显著低于低水盐环境(P<0.05),物种多样性指数Fish-α显著高于低水盐环境;(2)一元与多元回归分析均表明,高水盐环境下物种多样性对功能多样性RaoQ与FRic指数有显著促进作用,低水盐环境下物种多样性对功能多样性和均匀度有显著促进作用,但对功能离散度具有显著抑制作用(P<0.05);(3)物种多样性对功能多样性的影响在低水盐环境下更显著,预测力更强;(4)功能丰富度、离散度与均匀度能较敏感地反映出荒漠植物功能多样性对水盐变化的响应.本研究有助于理解荒漠植物群落构建机制,并为荒漠植物恢复与管理提供理论参考.     

用功能生态学方法揭示峨眉髭蟾蝌蚪和棘腹蛙蟾蝌蚪共存的原因

采用功能生态学的研究方法,选取了3个指标(功能丰富度、功能定位和功能生态位的重叠程度)对峨眉山清音阁黑龙江中峨眉髭蟾蝌蚪和棘腹蛙蝌蚪共存的原因进行了解析。结果表明,峨眉髭蟾蝌蚪功能丰富度的实测值远远小于棘腹蛙蝌蚪。采用自助法随机抽样15和51个个体时,峨眉髭蟾蝌蚪的功能丰富度值显著小于棘腹蛙蝌蚪。同时,非参数多元方差分析的结果显示二者的功能定位存在显著差异。此外,二者功能生态位重叠程度的实测值与采用自助法计算所得值均极低。以上结果表明二者的功能生态位存在明显分化,表现为峨眉髭蟾蝌蚪个体较大,开口较小,眼间距较大,尾部发达且多采用背腹弯曲的游泳模式;而棘腹蛙蝌蚪开口较大,眼睛间距较小,尾部较为短小且多采用脊椎弯曲的游泳模式。鉴于功能性状可以反映生物体对生长环境的响应,推测两种蝌蚪主要栖息地的微生境也存在分化。     

广西马尾松林植物功能多样性与生产力的关系

探索植物多样性与生产力的关系可为森林经营与管理提供科学基础。本研究以广西4个地区的马尾松(Pinus massoniana)人工林群落为研究对象, 通过计算物种多样性、功能多样性和功能优势值, 运用相关分析、自动线性建模和方差划分等方法, 分析了多样性与生产力的关系。研究发现, 生产力与物种丰富度、Shannon指数、功能丰富度、功能均匀度极显著正相关(P < 0.01), 与物种均匀度、功能多样性、功能离散度、功能团个数、坡向显著正相关(P < 0.05), 与林龄极显著负相关(P < 0.01), 4个功能多样性参数和4个物种多样性参数两两之间皆为显著正相关; 未发现初始生物量制约生产力的提高; 方差划分最优模型中, 功能多样性参数效应、功能优势值效应和林龄效应分别解释生产力方差的56%、43%和33%, 功能多样性参数效应和功能优势值效应重叠部分高达27%; 生态位互补效应主要由功能丰富度和功能均匀度产生, 选择效应主要由生长型优势值产生; 生长型优势值为灌木的样地生产力较高, 次优种或过渡种对生态系统功能也有重要作用。以生产力为响应变量的自动线性建模最佳子集包括重要性由大到小的5个因素: 林龄、生长型优势值、功能丰富度、功能均匀度、功能团个数。建议维护森林功能多样性, 加强林下叶层植物保护, 用好功能重要的物种, 通过林下叶层的补偿性光合作用和生长竞争, 有效地提高生产力和生物多样性。     

高寒草甸对刈割、施肥和浇水发生响应的最优植物性状集和功能型

基于植物性状和功能型的特征变化对于研究植被动态和生态系统功能变化具有重要意义。通过在高寒矮嵩草(Kobresia humilis)草甸为期5年(2007-2011年)的刈割(不刈割、留茬3 cm、留茬1 cm)、施肥(施肥、不施肥)和浇水(浇水、不浇水)控制实验, 采用递归算法(recursive algorithm)和多元回归分析筛选对模拟放牧发生响应的最优植物性状集和响应功能型, 以及影响群落生产力变化的作用功能型。研究结果显示: (1)在不施肥不浇水、仅施肥、仅浇水和既施肥又浇水4种条件下的最优植物性状集不同, 它们分别是叶缘形状-株高-叶干质量-比叶面积、生活周期-株高-叶干质量-比叶面积、生活周期-叶片叶绿素含量-叶表面结构-株高-叶干质量-比叶面积和繁殖结构-叶缘-株高。其中, 株高、叶干质量和比叶面积是对刈割和土壤资源变化更为敏感的植物性状。(2)在这4种处理条件下, 共获得14个最优响应功能型和4个作用功能型。作用功能型对群落生产力变异的解释能力在50.3%-86.4%之间。(3)最优响应功能型和作用功能型分别占功能型总数的70%和20%。作用功能型占最优响应功能型的28.5%, 两者间仅存在部分重叠。上述结果说明, 植物功能性状和功能型变化能够准确地反映植被的放牧响应和生态系统功能变化, 但是不同资源条件下群落的最优响应性状集和功能型不同。作用功能型是同时反映植被放牧响应和生态系统功能变化的最优功能型。     

山西五鹿山森林群落木本植物功能多样性

通过选取群落中木本植物种子的扩散方式、传粉方式、植株高度和盖度等13个功能性状,计算出群落的6个功能多样性指数:功能性状距离、功能性状平均距离、功能体积、功能均匀度、功能分散指数和Rao二次熵指数,结合群落物种丰富度指数、Shannon-Wiener指数和物种均匀度指数对山西五鹿山森林群落木本植物功能多样性进行研究。结果表明:(1)功能性状距离、功能性状平均距离、功能体积与物种丰富度、Shannon-Wiener指数显著正相关;功能均匀度与Shannon-Wiener指数、物种均匀度指数显著正相关;功能分散指数、Rao二次熵指数与物种均匀度指数、Shannon-Wiener指数显著正相关;(2)功能多样性的差异很大程度上是由于物种差异所引起的;(3)6个功能多样性指数可分为三类:功能性状距离、功能性状平均距离、功能体积为功能丰富度指数;功能均匀度为功能均匀度指数;功能分散指数和Rao二次熵指数为功能离散度指数。该分类结果符合指数的计算方法和生态学意义,以及相互独立的标准。     

淡水鱼类功能生态学研究进展

在全球变化和人类活动的影响下,生物多样性正以前所未有的速度丧失,全球生物正经受第六次生物多样性危机。淡水生态系统是最脆弱的生态系统之一。淡水鱼类作为淡水生态系统的重要组成部分,承受着日趋严重的气候变化、栖息地退化、生物入侵和过度捕捞等压力,面临巨大的威胁。在此背景下,如何准确评估鱼类种群和群落对环境变化的响应,以及鱼类群落结构和功能的变化对生态系统功能的影响是淡水鱼类多样性和淡水生态系统保护的关键问题。近年来,淡水鱼类功能生态学的快速发展为解答这一问题提供了一个框架。系统地介绍了淡水鱼类功能生态学主要研究内容、方法、进展及其应用,并着重介绍了淡水鱼类功能特征及其与环境的关系、环境变化下的功能生态学响应研究。据此提出了淡水鱼类功能生态学未来的重点研究方向,指出了其在鱼类多样性保护和资源利用等领域的应用前景。     

环境因子对山西太岳山典型森林类型物种多样性及其功能多样性的影响

该研究采用典型样地法,调查群落内物种分布并测量植物功能性状(叶面积和植株高度),对山西太岳山不同坡位华北落叶松-白桦混交林以及辽东栎次生林物种多样性及其功能多样性进行比较分析,探究环境因子对不同群落层次(乔木、灌木、草本)物种多样性及其功能多样性的影响机制,以及环境因子与群落构建之间的联系,为森林生态系统多样性研究以及经营管理提供理论依据。结果显示:(1)华北落叶松-白桦混交林的物种分布更加均匀,物种多样性和功能多样性(乔木层)均显著高于辽东栎次生林。(2)华北落叶松-白桦混交林乔木层功能均匀度与功能分散指数显著高于辽东栎次生林,但灌木草本层低于辽东栎次生林。(3)不同群落层次的物种多样性与功能多样性均呈正相关关系,影响物种分布和性状分布的环境因子存在差异,物种多样性受多种环境因子的综合影响,而单个环境因子对功能多样性影响较大,环境解释力与林分类型和群落层次相关。(4)乔木层物种多样性主要受土壤pH、冠层结构(MLA、林分开度)以及光照影响,灌木层物种多样性与土壤pH和MLA密切相关,林下总辐射、土壤养分(SOC、STN)、土壤相对含水率是影响草本层物种分布的主要环境因子;冠层结构(MLA、林分开度)是影响乔木层功能多样性最主要的环境因子,土壤pH和坡位分别是华北落叶松-白桦混交林和辽东栎次生林灌木层功能多样性的主要影响因子,影响草本层功能多样性的主要环境因子是土壤相对含水率与LAI。研究表明,在垂直分层的森林生态系统中,不同群落层次竞争的主要环境资源存在差异,乔木层通过改变冠层结构和林内环境限制林下物种分布和性状分布。     

Functional diversity (FD), species richness and community composition

Functional diversity is an important component of biodiversity, yet in comparison to taxonomic diversity, methods of quantifying functional diversity are less well developed. Here, we propose a means for quantifying functional diversity that may be particularly useful for determining how functional diversity is related to ecosystem functioning. This measure of functional diversity “FD” is defined as the total branch length of a functional dendrogram. Various characteristics of FD make it preferable to other measures of functional diversity, such as the number of functional groups in a community. Simulating species' trait values illustrates how the relative importance of richness and composition for FD depends on the effective dimensionality of the trait space in which species separate. Fewer dimensions increase the importance of community composition and functional redundancy. More dimensions increase the importance of species richness and decreases functional redundancy. Clumping of species in trait space increases the relative importance of community composition. Five natural communities show remarkably similar relationships between FD and species richness.     

A functional perspective for breeding and wintering waterbird communities: temporal trends in species and trait diversity

Waterbird communities are prone to strong temporal changes both seasonally and annually, but little is known about how this affects their functional diversity and community assembly. Detecting temporal trends in taxonomic and functional diversity within (alpha diversity) and between (beta diversity) communities in breeding and wintering seasons could give insight into the ecological processes driving those trends. In this study, we investigated trends in wintering and breeding waterbirds within and between eleven wetlands in Mediterranean Spain, using a 28‐year time‐series up to 2017. We assessed the temporal trends in taxonomic and functional diversity measures, and compared observed functional diversity values with null expectations, in order to explore the mechanisms driving community assembly. We found increases over time in species richness and in the occupied functional space for both wintering and breeding communities, indicating that species with distinct functional roles were added in both seasons. However, the distribution of the abundances in the functional space was different for breeding and wintering communities. Dissimilarity of species and functional traits decreased among wetlands, suggesting that some of the same functional traits were added to the different wetlands, increasing regional homogenization through time. This is reflected in increases over time in mean body mass, diet plasticity and in the importance of fish in waterbird diets, plus declines in the dietary importance of invertebrates and in plasticity of feeding strata. Furthermore, species composition between wintering and breeding communities, but not trait composition, has become more similar through time. Our results highlight that annual changes, and especially seasonal changes, in the composition of waterbird communities have different effects on their functional diversity, and are influenced by opposing community assembly mechanisms.     

The biogeography and filtering of woody plant functional diversity in North and South America

Aim In recent years evidence has accumulated that plant species are differentially sorted from regional assemblages into local assemblages along local‐scale environmental gradients on the basis of their function and abiotic filtering. The favourability hypothesis in biogeography proposes that in climatically difficult regions abiotic filtering should produce a regional assemblage that is less functionally diverse than that expected given the species richness and the global pool of traits. Thus it seems likely that differential filtering of plant traits along local‐scale gradients may scale up to explain the distribution, diversity and filtering of plant traits in regional‐scale assemblages across continents. The present work aims to address this prediction. Location North and South America. Methods We combine a dataset comprising over 5.5 million georeferenced plant occurrence records with several large plant functional trait databases in order to: (1) quantify how several critical traits associated with plant performance and ecology vary across environmental gradients; and (2) provide the first test of whether the woody plants found within 1° and 5° map grid cells are more or less functionally diverse than expected, given their species richness, across broad gradients. Results The results show that, for many of the traits studied, the overall distribution of functional traits in tropical regions often exceeds the expectations of random sampling given the species richness. Conversely, temperate regions often had narrower functional trait distributions than their smaller species pools would suggest. Main conclusion The results show that the overall distribution of function does increase towards the equator, but the functional diversity within regional‐scale tropical assemblages is higher than that expected given their species richness. These results are consistent with the hypothesis that abiotic filtering constrains the overall distribution of function in temperate assemblages, but tropical assemblages are not as tightly constrained.     

功能多样性和功能冗余对高寒草甸群落稳定性的影响

功能多样性和功能冗余是影响群落稳定性的重要因素,但它们对稳定性影响的相对强弱尚有争论。通过在青藏高原高寒矮嵩草(Kobresia humilis)草甸为期6a的刈割(不刈割、留茬3cm、留茬1cm)和施肥(施肥、不施肥)控制实验对此进行了探讨。研究结果显示,群落稳定性随着功能多样性和功能冗余的增大而单调增加,但由于功能多样性的变异性大于功能冗余的变异性,功能多样性与物种多样性间的相关性强于功能冗余与物种多样性间的相关性,功能多样性与群落稳定性间的相关性也强于功能冗余与群落稳定性间的相关性,因此,尽管功能冗余产生的保险效应对维持群落稳定性具有促进作用,但功能多样性的互补效应对维持群落稳定性的作用更大。结果表明,功能多样性和功能冗余对群落稳定性的相对影响与其变化程度正相关,功能多样性与群落稳定性的变化具有更紧密的联系,能更好地预测生态系统稳定性的变化。研究为草原生态系统的可持续管理提供了重要启示。