Explaining variation in productivity requires intraspecific variability in plant height among communities

Abstract Aims While recent studies have shown the importance of intraspecific trait variation in the processes of community assembly, we still know little about the contributions of intraspecific trait variability to ecosystem functions. Methods Here, we conducted a functional group removal experiment in an alpine meadow in Qinghai-Tibetan Plateau over four years to investigate the relative importance of inter- and intra-specific variability in plant height for productivity. We split total variability in plant height within each of 75 manipulated communities into interspecific variability (TVinter) and intraspecific variability within a community (ITVwithin). Community weighted mean height among communities was decomposed into fixed community weighted mean (CWMfixed) and intraspecific variability among communities (ITVamong). We constructed a series of generalized additive mixed models and piecewise structural equation modelling to determine how trait variability (i.e., TVinter, ITVwithin, CWMfixed and ITVamong) indirectly mediated the changes in productivity in response to functional group removal. Important Findings Community productivity was not only affected directly by treatment manipulations, but also increased with both inter- and intra-specific variability (i.e., CWMfixed, ITVamong) in plant height indirectly. This suggests that both the “selection effect” and a “shade-avoidance syndrome” can incur higher CWMfixed and ITVamong, and may simultaneously operate to regulate productivity. Our findings provide new evidence that, besides interspecific variability, intraspecific trait variability in plant height also plays a role in maintaining net primary productivity.

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Phenotypic plasticity can reverse the relative extent of intra- and interspecific variability across a thermal gradient

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2021.0428 ◽

2021 ◽

Vol 288 (1953) ◽

pp. 20210428

Author(s):

Staffan Jacob ◽

Delphine Legrand

Keyword(s):

Phenotypic Plasticity ◽

Thermal Gradient ◽

Environmental Gradients ◽

Intraspecific Variability ◽

Functional Trait ◽

Ecosystem Functions ◽

Interspecific Variability ◽

Ciliate Species ◽

Relative Extent ◽

Trait Variability

Intra- and interspecific variability can both ensure ecosystem functions. Generalizing the effects of individual and species assemblages requires understanding how much within and between species trait variation is genetically based or results from phenotypic plasticity. Phenotypic plasticity can indeed lead to rapid and important changes of trait distributions, and in turn community functionality, depending on environmental conditions, which raises a crucial question: could phenotypic plasticity modify the relative importance of intra- and interspecific variability along environmental gradients? We quantified the fundamental niche of five genotypes in monocultures for each of five ciliate species along a wide thermal gradient in standardized conditions to assess the importance of phenotypic plasticity for the level of intraspecific variability compared to differences between species. We showed that phenotypic plasticity strongly influences trait variability and reverses the relative extent of intra- and interspecific variability along the thermal gradient. Our results show that phenotypic plasticity may lead to either increase or decrease of functional trait variability along environmental gradients, making intra- and interspecific variability highly dynamic components of ecological systems.

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Accounting for underlying complexities identifies simple hierarchy of trait‒environment relationships in Wisconsin forest understory communities

10.1101/2020.11.17.387050 ◽

2020 ◽

Author(s):

Andrés G. Rolhauser ◽

Donald M. Waller ◽

Caroline M. Tucker

Keyword(s):

Observational Data ◽

Plant Height ◽

Mixed Model ◽

Environmental Gradients ◽

Functional Structure ◽

Forest Understory ◽

Weighted Mean ◽

Community Weighted Mean ◽

Understory Communities ◽

Positive Effect

AbstractAdaptive relationships between traits and the environment are often inferred from observational data by regressing community-weighted mean (CWM) traits on environmental gradients. However, trait‒environment relationships are better understood as the outcome of trait‒abundance and environment‒abundance relationships, and the interaction between traits and the environment. Accounting for this functional structure and for interrelationships among traits should improve our ability to accurately describe general trait‒environment relationships. Using forest understory communities in Wisconsin, we applied a generalized mixed model (GLMM) incorporating this structure. We identified a simple hierarchy of trait‒environment relationships dominated by a strong positive effect of mean temperature on plant height. Compared to the traditional CWM approach, the GLMM was more conservative in identifying significant trait‒environment relationships, and also detected important relationships that CWM regressions overlooked. This work highlights the need to consider the complexity underlying trait‒environment relationships in future analyses.

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Effect of Grazing Types on Community-Weighted Mean Functional Traits and Ecosystem Functions on Inner Mongolian Steppe, China

Sustainability ◽

10.3390/su12177169 ◽

2020 ◽

Vol 12 (17) ◽

pp. 7169

Author(s):

Wen Wang ◽

Huamin Liu ◽

Jinghui Zhang ◽

Zhiyong Li ◽

Lixin Wang ◽

...

Keyword(s):

Functional Traits ◽

Nutrient Content ◽

Co2 Exchange ◽

Ecosystem Functions ◽

Weighted Mean ◽

Nitrogen And Phosphorus ◽

Inner Mongolia Grassland ◽

Grassland Ecosystems ◽

Community Weighted Mean ◽

Set Up

The relationships between community-weighted mean (CWM) functional traits and ecosystem functions have been extensively studied. However, how CWM traits and ecosystem functions respond to grazing types and whether the relationships between CWM traits and ecosystem functions mediate the response of ecosystem functions to grazing types remains controversial. In the present study, we set up a seven-year grazing experiment with four grazing types: no grazing (NG), cattle grazing (CG), sheep grazing (SG), and mixed grazing by sheep and cattle (MG) on Inner Mongolia grassland. Nine functional traits of dominant species and five ecosystem functions under different grazing types were determined, and the relationships between CWM traits and ecosystem functions were analyzed. The results showed that the CWM height decreased after grazing, while the CWM nitrogen and phosphorus contents increased after CG. SG caused a greater decrease in aboveground biomass (AGB) and a greater increase in the net ecosystem CO2 exchange (NEE) of grassland ecosystems than did CG. This result may be partially because the CWM nutrient content and NEE were more negatively related after CG; and the increase in the CWM nitrogen and phosphorus contents suppressed NEE after CG. Therefore, to protect the sustainability of grassland ecosystem functions, SG should be reduced. Additionally, our work emphasizes that the relationships between plant functional traits and ecosystem functions may mediate the response of ecosystem functions to grazing types.

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Leaf trait variability between and within subalpine grassland species differs depending on site conditions and herbivory

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2019.0429 ◽

2019 ◽

Vol 286 (1907) ◽

pp. 20190429 ◽

Cited By ~ 1

Author(s):

Jennifer Firn ◽

Huong Nguyen ◽

Martin Schütz ◽

Anita C. Risch

Keyword(s):

Plant Traits ◽

Intraspecific Variability ◽

Leaf Traits ◽

Nutrient Concentrations ◽

Phosphorus Concentration ◽

Geographical Differences ◽

Leaf Trait ◽

Interspecific Variability ◽

Herbivore Exclusion ◽

Trait Variability

Plant traits are commonly used to predict ecosystem-level processes, but the validity of such predictions is dependent on the assumption that trait variability between species is greater than trait variability within a species—the robustness assumption. Here, we compare leaf trait intraspecific and interspecific variability depending on geographical differences between sites and 5 years of experimental herbivore exclusion in two vegetation types of subalpine grasslands in Switzerland. Four leaf traits were measured from eight herbaceous species common to all 18 sites. Intraspecific trait variability differed significantly depending on site and herbivory. However, the amount and structure of variability depended on the trait measured and whether considering leaf traits separately or multiple leaf traits simultaneously. Leaf phosphorus concentration showed the highest intraspecific variability, while specific leaf area showed the highest interspecific variability and displayed intraspecific variability only in response to herbivore exclusion. Species identity based on multiple traits was not predictable. We find intraspecific variability is an essential consideration when using plant functional traits as a common currency not just species mean traits. This is particularly true for leaf nutrient concentrations, which showed high intraspecific variability in response to site differences and herbivore exclusion, a finding which suggests that the robustness assumption does not always hold.

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Accounting for underlying complexities identifies simple hierarchy of trait‒environment relationships in Wisconsin forest understory communities

10.22541/au.160614552.23429727/v1 ◽

2020 ◽

Author(s):

Andres Rolhauser ◽

Don Waller ◽

Caroline Tucker

Keyword(s):

Observational Data ◽

Plant Height ◽

Mixed Model ◽

Environmental Gradients ◽

Functional Structure ◽

Forest Understory ◽

Weighted Mean ◽

Community Weighted Mean ◽

Understory Communities ◽

Positive Effect

Adaptive relationships between traits and the environment are often inferred from observational data by regressing community-weighted mean (CWM) traits on environmental gradients. However, trait‒environment relationships are better understood as the outcome of trait‒abundance and environment‒abundance relationships, and the interaction between traits and the environment. Accounting for this functional structure and for interrelationships among traits should improve our ability to accurately describe general trait‒environment relationships. Using forest understory communities in Wisconsin, we applied a generalized mixed model (GLMM) incorporating this structure. We identified a simple hierarchy of trait‒environment relationships dominated by a strong positive effect of mean temperature on plant height. Compared to the traditional CWM approach, the GLMM was more conservative in identifying significant trait‒environment relationships, and also detected important relationships that CWM regressions overlooked. This work highlights the need to consider the complexity underlying trait‒environment relationships in future analyses

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Exploring the relationship between functional structure and ecosystem multifunctionality requires intraspecific trait variability

10.1101/2020.11.03.366054 ◽

2020 ◽

Author(s):

Li Zhang ◽

Bill Shipley ◽

Shurong Zhou

Keyword(s):

Intraspecific Variability ◽

Nitrogen Addition ◽

High Threshold ◽

List Type ◽

Relative Contribution ◽

The Face ◽

Ecosystem Multifunctionality ◽

Intraspecific Trait Variability ◽

Trait Variability

AbstractRecent studies have shown that intraspecific trait variability is an important source of total trait variation in the face of global change. However, the contribution of intraspecific variability to ecosystem multifunctionality remains unknown.We calculated the mean and variability of four functional traits in an alpine meadow under long-term nitrogen addition and experimental warming and split them into interspecific and intraspecific variabilities. We then investigated their net effects and relative importance in determining ecosystem multifunctionality.We found that the effect of trait variability on multifunctionality depended not only on the number of functions, but also on the thresholds considered. Trait variability dominating ecosystem multifunctionality switched from interspecific to intraspecific when the thresholds of multifunctionality varied from low to high levels. When more functions were considered to interpret multifunctionality above high threshold levels, the relative contribution of intraspecific variability would be more important.

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Intraspecific trait variability of a typical tree species of riverine forests in southern Brazil

Flora ◽

10.1016/j.flora.2021.151806 ◽

2021 ◽

Vol 279 ◽

pp. 151806

Author(s):

Edilvane Inês Zonta ◽

Guilherme Krahl de Vargas ◽

João André Jarenkow

Keyword(s):

Tree Species ◽

Southern Brazil ◽

Riverine Forests ◽

Intraspecific Trait Variability ◽

Trait Variability

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Linking functional group richness and ecosystem functions of dung beetles: an experimental quantification

Oecologia ◽

10.1007/s00442-016-3756-5 ◽

2016 ◽

Vol 183 (1) ◽

pp. 177-190 ◽

Cited By ~ 6

Author(s):

Tanja Milotić ◽

Stijn Quidé ◽

Thomas Van Loo ◽

Maurice Hoffmann

Keyword(s):

Functional Group ◽

Dung Beetles ◽

Ecosystem Functions

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Australian endemic Drosophila I. Tasmania and Victoria, including descriptions of two new species

Australian Journal of Zoology ◽

10.1071/zo9770249 ◽

1977 ◽

Vol 25 (2) ◽

pp. 249 ◽

Cited By ~ 6

Author(s):

PA Parsons ◽

IR Bock

Keyword(s):

New South ◽

Intraspecific Variability ◽

Distribution Patterns ◽

Progressive Reduction ◽

Upland Forest ◽

Interspecific Variability ◽

South Wales ◽

Forest Regions ◽

Southern Species ◽

Marginal Habitats

The endemic Drosophila fauna of southern Australia consists principally of species of the typically Australian subgenus Scaptodrosophila. In Tasmania and Victoria (but less so further north), the inornata group of species within the subgenus predominates. With one exception, none of the southern species is found further north than the upland forest regions of the Queensland-New South Wales border, this being the most northern extension of floral elements of the temperate rain forests of the south. Species diversities increase with decreasing latitude, presumably because of the dependence of Drosophila species on the flora which itself becomes more diverse with decreasing latitude. Evidence is presented for a progressive reduction of niches available or exploited with increasing latitude. In very marginal habitats interspecific variability is low, paralleling low genetic intraspecific variability often found in such habitats. Species distributions are probably highly dependent upon density-independent factors of the climate, so that past climatic shifts would have been important in leading to distribution patterns found today of Drosophila populations in 'insular islands of vegetation' surrounded by unsuitable habitats.

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