Seven Shortfalls that Beset Large-Scale Knowledge of Biodiversity

Annual Review of Ecology Evolution and Systematics, Journal Year: 2015, Volume and Issue: 46(1), P. 523 - 549

Published: Oct. 30, 2015

Ecologists and evolutionary biologists are increasingly using big-data approaches to tackle questions at large spatial, taxonomic, temporal scales. However, despite recent efforts gather two centuries of biodiversity inventories into comprehensive databases, many crucial research remain unanswered. Here, we update the concept knowledge shortfalls review tradeoffs between generality uncertainty. We present seven key current data. Four previously proposed pinpoint gaps for species taxonomy (Linnean), distribution (Wallacean), abundance (Prestonian), patterns (Darwinian). also redefine Hutchinsonian shortfall apply abiotic tolerances propose new relating limited traits (Raunkiæran) biotic interactions (Eltonian). conclude with a general framework combined impacts consequences large-scale ecological consider ways overcoming dealing uncertainty they generate.

Language: Английский

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A TRAIT-BASED TEST FOR HABITAT FILTERING: CONVEX HULL VOLUME

Ecology, Journal Year: 2006, Volume and Issue: 87(6), P. 1465 - 1471

Published: June 1, 2006

Community assembly theory suggests that two processes affect the distribution of trait values within communities: competition and habitat filtering. Within a local community, leads to ecological differentiation coexisting species, while filtering reduces spread values, reflecting shared tolerances. Many statistical tests for effects exist in literature, but measures are less well-developed. Here, we present convex hull volume, construct from computational geometry, which provides an n-dimensional measure volume space occupied by species community. Combined with null models, this offers useful test We use model analyze California woody-plant community data. Our results show observed plant communities occupy than expected random assembly, result consistent

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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Community assembly and shifts in plant trait distributions across an environmental gradient in coastal California

Ecological Monographs, Journal Year: 2009, Volume and Issue: 79(1), P. 109 - 126

Published: Feb. 1, 2009

Community assembly processes are thought to shape the mean, spread, and spacing of functional trait values within communities. Two broad categories have been proposed: first, a habitat filter that restricts range viable strategies second, partitioning microsites and/or resources leads limit similarity coexisting species. The strength both may be dependent on conditions at particular site change along an abiotic gradient. We sampled environmental variables plant communities in 44 plots across varied topography coastal California landscape. characterized 14 leaf, stem, root traits for 54 woody species, including detailed intraspecific data two with goal understanding connection between variety conditions. examined within‐community range, variance, kurtosis, other measures values. In this landscape, there was topographically mediated gradient water availability. Across we observed strong shifts plot‐level mean variation Trends means environment were due largely species turnover, playing smaller role. Traits associated vertical light showed greater variance wet soils, while nitrogen per area, which is use efficiency, spread dry soils. found nonrandom patterns distributions consistent expectations based trait‐mediated community assembly. There significant reduction six out 11 leaf stem relative null model. For specific area (SLA) even seed size more platykurtic distribution than expected. These results suggest can simultaneously local

Language: Английский

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Plant trait responses to grazing – a global synthesis

Global Change Biology, Journal Year: 2006, Volume and Issue: 13(2), P. 313 - 341

Published: Oct. 27, 2006

Abstract Herbivory by domestic and wild ungulates is a major driver of global vegetation dynamics. However, grazing not considered in dynamic models, or more generally studies the effects environmental change on ecosystems at regional to scale. An obstacle this lack empirical tests several hypotheses linking plant traits with grazing. We, therefore, set out test whether some widely recognized trait responses are consistent level. We conducted meta‐analysis grazing, based 197 from all regions world, using six conceptual models response as framework. Data were available for seven traits: life history, canopy height, habit, architecture, growth form (forb, graminoid, herbaceous legume, woody), palatability, geographic origin. Covariates precipitation evolutionary history herbivory. Overall, favoured annual over perennial plants, short plants tall prostrate erect stoloniferous rosette architecture tussock architecture. There was no effect form. Some patterns modified particular combinations Climatic historical contexts therefore essential understanding Our study identifies key be incorporated into functional classifications explicit consideration used research. Importantly, our results suggest that type rules need specific different climate herbivory history.

Language: Английский

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Towards an assessment of multiple ecosystem processes and services via functional traits

Biodiversity and Conservation, Journal Year: 2010, Volume and Issue: 19(10), P. 2873 - 2893

Published: April 9, 2010

Language: Английский

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Functional traits and the growth–mortality trade‐off in tropical trees

Ecology, Journal Year: 2010, Volume and Issue: 91(12), P. 3664 - 3674

Published: June 22, 2010

A trade-off between growth and mortality rates characterizes tree species in closed canopy forests. This is maintained by inherent differences among spatial variation light availability caused canopy-opening disturbances. We evaluated conditions under which the expressed relationships with four key functional traits for 103 from Barro Colorado Island, Panama. The strongest saplings of fastest growing individuals slowest (r2 = 0.69), intermediate average overall 0.46), much weaker large trees < or 0.10). parallels likely levels availability, greatest fast- vs. slow-growing least foliage forest canopy. Inherent attributes contributing to include abilities disperse, acquire resources, grow rapidly, tolerate shade other stresses. There interest possibility that might provide insight into such ecological a consensus seed mass (SM), leaf per area (LMA), wood density (WD), maximum height (H(max)) are trees. Seed mass, LMA, WD, H(max) predicted be small light-demanding rapid shade-tolerant slow mortality. Six these trait-demographic rate predictions were realized saplings; however, exception weak 0.1 three r2 0.2 five six remaining relationships). together explained 43-44% interspecific positions on growth-mortality trade-off; WD alone accounted > 80% and, after was included, LMA made insignificant contributions. Virtually full range values SM, occurred at all trade-off. Although provides promising start, successful trait-based ecology tropical will require consideration additional traits.

Language: Английский

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Plant functional traits and the multidimensional nature of species coexistence

Proceedings of the National Academy of Sciences, Journal Year: 2015, Volume and Issue: 112(3), P. 797 - 802

Published: Jan. 5, 2015

Understanding the processes maintaining species diversity is a central problem in ecology, with implications for conservation and management of ecosystems. Although biologists often assume that trait differences between competitors promote diversity, empirical evidence connecting functional traits to niche stabilize coexistence rare. Obtaining such critical because also underlie average fitness driving competitive exclusion, this complicates efforts infer community dynamics from phenotypic patterns. We coupled field-parameterized mathematical models competition 102 pairs annual plants detailed sampling leaf, seed, root, whole-plant relate stabilizing differences. Single were well correlated species, indicating dominance was associated late phenology, deep rooting, several other traits. In contrast, single poorly coexistence. Niche could only be described by combinations traits, corresponding differentiation multiple ecological dimensions. addition, both These complex relationships competing argue against simple use assembly but lay groundwork theoretically justified trait-based ecology.

Language: Английский

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Assessing functional diversity in the field – methodology matters!

Functional Ecology, Journal Year: 2007, Volume and Issue: 22(1), P. 134 - 147

Published: Nov. 22, 2007

1 Interpreting the functional diversity of vegetation is important in unravelling relationship between environmental change, community composition and ecosystem processes. Functional range distribution trait values a community. It can be described, among other indicators, by community-level weighted means (CWM) divergence. Standard methods exist for measurements but not assessments CWM divergence field. No research has addressed effects different estimating relative abundances, nor need to estimate traits at individual, population or species level, whether could used that bypass taxonomy all together. 2 This study reviews evaluates plot-level assessment herbaceous vegetation. We asked: (i) Should objective influence method abundance? (ii) What are strengths limitations intensive vs. 'rapid' approaches, when should either applied? (iii) Are taxon-free robust comparison taxon-explicit measurement? Under what circumstances might they 3 Our review published studies have measured field showed choice metric generally taken into account link functions interest, cover been most widely used, regardless purpose. 4 compared quantitatively subalpine grasslands three quantification abundances plus one method. found that: data base were across years diverse set dominant species; little sensitivity abundances; this also depends on traits, example, seed mass results less stable than leaf heights; estimates obtained from visual ranks biomass using dry-weight ranking (BOTANAL), whereas was more sensitive method; (iv) treated with caution performed particularly poorly 5 conclude methodology affect diversity. Although care interpretation results, rapid often offer promising avenues sampling larger areas and/or repeated measures.

Language: Английский

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Global shifts towards positive species interactions with increasing environmental stress

Ecology Letters, Journal Year: 2013, Volume and Issue: 16(5), P. 695 - 706

Published: Jan. 30, 2013

The study of positive species interactions is a rapidly evolving field in ecology. Despite decades research, controversy has emerged as to whether and negative predictably shift with increasing environmental stress hypothesised by the stress-gradient hypothesis (SGH). Here, we provide synthesis 727 tests SGH plant communities across globe examine its generality variety ecological factors. Our results show that change through an outright facilitation (survival) or reduction competition (growth reproduction). In limited number cases, do not respond stress, but they never towards stress. These findings are consistent types, growth forms, life histories, origins (invasive vs. native), climates, ecosystems methodologies, though magnitude shifts dependent on these We suggest future studies should employ standardised definitions protocols test SGH, take multi-factorial approach considers variables such traits addition apply better understand how will change.

Language: Английский

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