NEW MULTIDIMENSIONAL FUNCTIONAL DIVERSITY INDICES FOR A MULTIFACETED FRAMEWORK IN FUNCTIONAL ECOLOGY

Ecology, Journal Year: 2008, Volume and Issue: 89(8), P. 2290 - 2301

Published: Aug. 1, 2008

Functional diversity is increasingly identified as an important driver of ecosystem functioning. Various indices have been proposed to measure the functional a community, but there still no consensus on which are most suitable. Indeed, none existing meets all criteria required for general use. The main that they must be designed deal with several traits, take into account abundances, and facets diversity. Here we propose three quantify each facet community species distributed in multidimensional space: richness (volume space occupied by community), evenness (regularity distribution abundance this volume), divergence (divergence volume). estimated using convex hull volume index. new index based minimum spanning tree links space. Then quantifies regularity abundances along tree. measured novel how diverge their distances (weighted abundance) from center gravity We show index, instead set complementary these criteria. Through simulations artificial data sets, demonstrate independent other. Overall, our study suggests decomposition its primary components provides meaningful framework quantification classification indices. This has potential shed light role biodiversity functioning influence biotic abiotic filters structure communities. Finally, applying

Language: Английский

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The global spectrum of plant form and function

Nature, Journal Year: 2015, Volume and Issue: 529(7585), P. 167 - 171

Published: Dec. 23, 2015

Language: Английский

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TRY – a global database of plant traits

Global Change Biology, Journal Year: 2011, Volume and Issue: 17(9), P. 2905 - 2935

Published: April 26, 2011

Abstract Plant traits – the morphological, anatomical, physiological, biochemical and phenological characteristics of plants their organs determine how primary producers respond to environmental factors, affect other trophic levels, influence ecosystem processes services provide a link from species richness functional diversity. Trait data thus represent raw material for wide range research evolutionary biology, community ecology biogeography. Here we present global database initiative named TRY, which has united plant trait worldwide gained an unprecedented buy‐in data: so far 93 databases have been contributed. The repository currently contains almost three million entries 69 000 out world's 300 species, with focus on 52 groups characterizing vegetative regeneration stages life cycle, including growth, dispersal, establishment persistence. A first analysis shows that most are approximately log‐normally distributed, widely differing ranges variation across traits. Most is between (interspecific), but significant intraspecific also documented, up 40% overall variation. types (PFTs), as commonly used in vegetation models, capture substantial fraction observed several occurs within PFTs, 75% In context models these would better be represented by state variables rather than fixed parameter values. improved availability unified expected support paradigm shift trait‐based ecology, offer new opportunities synthetic enable more realistic empirically grounded representation terrestrial Earth system models.

Language: Английский

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A functional approach reveals community responses to disturbances

Trends in Ecology & Evolution, Journal Year: 2012, Volume and Issue: 28(3), P. 167 - 177

Published: Nov. 8, 2012

Language: Английский

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Cross‐validation strategies for data with temporal, spatial, hierarchical, or phylogenetic structure

Ecography, Journal Year: 2016, Volume and Issue: 40(8), P. 913 - 929

Published: Dec. 9, 2016

Ecological data often show temporal, spatial, hierarchical (random effects), or phylogenetic structure. Modern statistical approaches are increasingly accounting for such dependencies. However, when performing cross‐validation, these structures regularly ignored, resulting in serious underestimation of predictive error. One cause the poor performance uncorrected (random) noted by modellers, dependence that persist as model residuals, violating assumption independence. Even more concerning, because overlooked, is structured also provides ample opportunity overfitting with non‐causal predictors. This problem can even if remedies autoregressive models, generalized least squares, mixed models used. Block where split strategically rather than randomly, address issues. blocking strategy must be carefully considered. Blocking space, time, random effects distance, while dependencies data, may unwittingly induce extrapolations restricting ranges combinations predictor variables available training, thus overestimating interpolation errors. On other hand, deliberate space improve error estimates extrapolation modelling goal. Here, we review ecological literature on non‐random and blocked cross‐validation approaches. We provide a series simulations case studies, which that, all instances tested, block nearly universally appropriate goal predicting to new selecting causal recommend used wherever exist dataset, no correlation structure visible fitted account correlations.

Language: Английский

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CAN STABLE ISOTOPE RATIOS PROVIDE FOR COMMUNITY-WIDE MEASURES OF TROPHIC STRUCTURE?

Ecology, Journal Year: 2007, Volume and Issue: 88(1), P. 42 - 48

Published: Jan. 1, 2007

Stable isotope ratios (typically of carbon and nitrogen) provide one representation an organism's trophic niche are widely used to examine aspects food web structure. Yet stable isotopes have not been applied quantitatively characterize community-wide structure (i.e., at the level entire web). We propose quantitative metrics that can be this end, drawing on similar approaches from ecomorphology research. For example, convex hull area occupied by species in δ13C–δ15N space is a total extent diversity within web, whereas mean nearest neighbor distance among all pairs measure packing space. To facilitate discussion opportunities limitations metrics, we empirical conceptual examples drawn Bahamian tidal creek webs. These illustrate how methodology quantify redundancy webs, as well link individual characteristics which they embedded. Building extensive applications ecologists, may new perspective structure, function, dynamics.

Language: Английский

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Community assembly, coexistence and the environmental filtering metaphor

Functional Ecology, Journal Year: 2014, Volume and Issue: 29(5), P. 592 - 599

Published: Sept. 16, 2014

Summary One of the most pervasive concepts in study community assembly is metaphor environmental filter, which refers to abiotic factors that prevent establishment or persistence species a particular location. The has its origins change during succession and plant dynamics, although it gained considerable attention recently as part surge interest functional trait phylogenetic‐based approaches communities. While filtering clear utility some circumstances, been challenging reconcile concept with recent developments ecological theory related coexistence. These advances suggest evidence used many studies assess insufficient distinguish from outcome biotic interactions. We re‐examine perspective coexistence theory. In an effort move discussion forward, we present simple framework for considering role environment shaping membership, review literature document typically highlight research challenges address coming years. current usage term empirical likely overstates tolerances play structure. recommend ‘environmental filtering’ only be refer cases where prevents absence interactions, 15% our presented such evidence. Finally, urge ecologists consider additional mechanisms aside by can shape pattern.

Language: Английский

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Functional diversity measures: an overview of their redundancy and their ability to discriminate community assembly rules

Functional Ecology, Journal Year: 2010, Volume and Issue: 24(4), P. 867 - 876

Published: March 15, 2010

Summary 1. Indices quantifying the functional aspect of biodiversity are essential in understanding relationships between biodiversity, ecosystem functioning and environmental constraints. Many indices diversity have been published but we lack consensus about what quantify, how redundant they which ones recommended. 2. This study aims to build a typology from artificial data sets encompassing various community structures (different assembly rules, species richness levels) identify set independent able discriminate rules. 3. Our results confirm that can be divided into three main categories, each these corresponding one diversity: richness, evenness divergence. Most highly correlated quantify while quadratic entropy ( Q ) represents mix Conversely, two (FEve FDiv respectively divergence) rather all others. The power analysis revealed some efficiently detect rules others performed poorly. 4. To accurately assess establish its with constraints, recommend investigating component separately appropriate index. Guidelines provided help choosing given issue being investigated. 5. demonstrates potential reveal processes structure biological communities. Combined complementary methods (phylogenetic taxonomic diversity), multifaceted framework will improve our interacts

Language: Английский

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Scaling environmental change through the community‐level: a trait‐based response‐and‐effect framework for plants

Global Change Biology, Journal Year: 2008, Volume and Issue: 14(5), P. 1125 - 1140

Published: Jan. 31, 2008

Abstract Predicting ecosystem responses to global change is a major challenge in ecology. A critical step that understand how changing environmental conditions influence processes across levels of ecological organization. While direct scaling from individual dynamics can lead robust and mechanistic predictions, new approaches are needed appropriately translate questions through the community level. Species invasion, loss, turnover all necessitate this processes, but predicting such changes may function notoriously difficult. We suggest community‐level be incorporated into predictions using trait‐based response–effect framework differentiates response (predicted by traits) effect on traits). develop response‐and‐effect functional framework, concentrating relationships among species' response, effect, abundance general concerning magnitude direction function. then detail several key research directions better scale effects These include (1) trait characterization, (2) linkages between traits, (3) importance species interactions expression, (4) incorporation feedbacks multiple temporal scales. Increasing rates extinction invasion modifying communities worldwide make agenda imperative.

Language: Английский

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Functional Traits and Niche-Based Tree Community Assembly in an Amazonian Forest

Science, Journal Year: 2008, Volume and Issue: 322(5901), P. 580 - 582

Published: Oct. 23, 2008

It is debated whether species-level differences in ecological strategy, which play a key role much of coexistence theory, are important structuring highly diverse communities. We examined the co-occurrence patterns over 1100 tree species 25-hectare Amazonian forest plot relation to field-measured functional traits. Using null model approach, we show that co-occurring trees often less ecologically similar than niche-free (neutral) predicts. Furthermore, find evidence for processes simultaneously drive convergence and divergence aspects plant suggesting at least two distinct niche-based occurring. Our results strategy differentiation among contributes maintenance diversity one most tropical forests world.

Language: Английский

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