Trade‐offs in community ecology: linking spatial scales and species coexistence

Ecology Letters, Год журнала: 2003, Номер 7(1), С. 69 - 80

Опубликована: Ноя. 27, 2003

Abstract Trade‐offs in species performances of different ecological functions is one the most common explanations for coexistence communities. Despite potential occurring at local or regional spatial scales, trade‐offs are typically approached a single scale. In recent years, ecologists have increasingly provided evidence importance community processes both and scales. This review summarizes theoretical predictions traits associated with under conditions We provide framework understanding trade‐offs, supportive empirical evidence. Predictions presented that link patterns diversity observed to lead Recent evolution which explores laboratory microcosm studies phylogenetic tests. Examining within can strong approach structure dynamics, while explaining diversity.

Язык: Английский

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Species–energy relationships at the macroecological scale: a review of the mechanisms

Biological reviews/Biological reviews of the Cambridge Philosophical Society, Год журнала: 2005, Номер 80(1), С. 1 - 25

Опубликована: Янв. 12, 2005

Correlations between the amount of energy received by an assemblage and number species that it contains are very general, at macro-scale such species-energy relationships typically follow a monotonically increasing curve. Whilst ecological literature frequent reports relationships, debate on their causal mechanisms is limited focuses role availability in controlling individuals assemblage. Assemblages from high-energy areas may contain more enabling to maintain larger, viable populations, whose lower extinction risk elevates richness. Other have, however, also been suggested. Here we identify clarify nine principal generate positive macro-scale. We critically assess assumptions applicability over range spatial scales, derive predictions for each evidence supports or refutes them. Our synthesis demonstrates all share least one with alternative mechanism. Some previous studies appear not have recognised extent shared predictions, this detract contribution mechanisms. The combination made mechanism is, unique, suggesting that, principle, conclusive tests possible. Sufficient testing has yet be conducted, no single currently unequivocal support. Each contribute some circumstances, but unlikely act simultaneously. Moreover, particularly likely frequently increased population size, niche position diversification rate noteworthy context.

Язык: Английский

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COEXISTENCE OF THE NICHE AND NEUTRAL PERSPECTIVES IN COMMUNITY ECOLOGY

Ecology, Год журнала: 2006, Номер 87(6), С. 1399 - 1410

Опубликована: Июнь 1, 2006

The neutral theory for community structure and biodiversity is dependent on the assumption that species are equivalent to each other in all important ecological respects. We explore what this concept of equivalence means communities, how such may arise evolutionarily, possibility equivalents relates previous ideas about niche differentiation. also show co-occurrence ecologically similar or not incompatible with as has been supposed, because relations can sometimes favor coexistence species. argue both evolutionary processes operate promote introduction sustain persistence many cases nearly embedded highly structured food webs. Future work should focus synthesizing perspectives rather than dichotomously debating whether models provide better explanations biodiversity.

Язык: Английский

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The interaction between predation and competition: a review and synthesis

Ecology Letters, Год журнала: 2002, Номер 5(2), С. 302 - 315

Опубликована: Март 10, 2002

This review discusses the interface between two of most important types interactions species, interspecific competition and predation. Predation has been claimed to increase, decrease, or have little effect on, strength, impact importance competition. There is confusion about both meaning these terms likelihood of, conditions required for, each outcomes. In this article we distinguish among three measures influence predation on competitive outcomes: short‐term per capita consumption growth rates, long‐term changes in density, probability coexistence. We then outline various theoretical mechanisms that can lead qualitatively distinct effects predators. The qualitative predators depend mechanism definition strength/impact. assessing empirical literature, ask: (1) What definitions strength/impact assumed? (2) Does strong evidence exist support one more possible produce a given outcome? (3) Do biases choice organism manipulation exist, are they likely influenced conclusions reached? conclude by discussing several unanswered questions, espouse stronger interchange approaches question.

Язык: Английский

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The Niche Concept Revisited: Mechanistic Models and Community Context

Ecology, Год журнала: 1995, Номер 76(5), С. 1371 - 1382

Опубликована: Июль 1, 1995

The niche concept is a central organizing aspect of modern ecology. Although its history has often been reviewed, the structure and connection to advances in ecological theory received less recent attention. I review using “mechanistic” models community identify two distinct components. One describes environmental requirements organisms other per capita impact on environment. argue that these correspond significant differences between Grinnell's Elton's concepts from previously discussed “habitat” vs. “functional” dichotomy. illustrate distinction requirement components resource competition keystone predators, discuss “Gause's axiom” conventional “niche theory” context suggest be elucidated by explicit reference components; “impact” (corresponding concept) describing instantaneous per—capita effects species environment, “requirement” responses environment Hutchinson's definition). This approach connects with individual—based can help provide more for concept.

Язык: Английский

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REVERSAL OF GRAZING IMPACT ON PLANT SPECIES RICHNESS IN NUTRIENT-POOR VS. NUTRIENT-RICH ECOSYSTEMS

Ecology, Год журнала: 1998, Номер 79(8), С. 2581 - 2592

Опубликована: Дек. 1, 1998

To test the hypothesis that impacts of grazers on plant species richness reverse under contrasting nutrient richness, we analyzed unpublished and published data from lake, stream, marine, grassland, forest ecosystems. We 30 studies providing 44 comparisons low vs. high grazing pressure in enriched or nutrient-rich non-enriched nutrient-poor All 19 ecosystems exhibited significantly lower than grazing. In contrast, 14 25 showed higher However, nine these no significant impact while two declines Based all comparisons, decreases with ecosystems, it increases Although seemed to produce more variable responses did rare cases produced a decline environments. suggest because limitation available resources prevents regrowth after grazing, which may not be case It is also possible an increase due dominance inedible species. Our observation grazer reversal have important implications for management diversity.

Язык: Английский

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Experimental Tests of the Dependence of Arthropod Diversity on Plant Diversity

The American Naturalist, Год журнала: 1998, Номер 152(5), С. 738 - 750

Опубликована: Ноя. 1, 1998

Because a diversity of resources should support consumers, most models predict that increasing plant increases animal diversity. We report results direct experimental test the dependence on sampled arthropods in well‐replicated grassland experiment which species richness and functional were directly manipulated. In simple regressions, both number planted ($$\mathrm{log}\,_{2}$$ transformed) groups significantly increased arthropod but not abundance. However, was only significant predictor when variables included ANOVAs or MANOVA. Although highly significant, regressions had low $$R^{2}$$ values, high intercepts (24 monocultures), shallow slopes. Analyses relations among plants trophic indicated herbivore influenced by plant, parasite, predator Furthermore, more strongly correlated with parasite than Together regression results, this suggests that, although diversity, local is also maintained by, turn maintains, parasites predators.

Язык: Английский

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Biodiversity, Ecosystem Functioning, and Human Wellbeing

Oxford University Press eBooks, Год журнала: 2009, Номер unknown

Опубликована: Июль 30, 2009

Abstract How will biodiversity loss affect ecosystem functioning, services, and human wellbeing? In an age of accelerating loss, this volume summarizes recent advances in biodiversity‐ecosystem functioning research explores the economics services. The first section development basic science provides a meta-analysis that quantitatively tests several hypotheses. second describes natural foundations research, including: quantifying functional diversity, field into predictive science, effects stability complexity, methods to quantify mechanisms by which diversity affects importance trophic structure, microbial ecology, spatial dynamics. third takes on further than it has ever gone dimension. six chapters cover most pressing environmental challenges humanity faces, including on: climate change mitigation, restoration degraded habitats, managed ecosystems, pollination, disease, biological invasions. remaining three consider economic perspective, synthesis services biodiversity, options open policy-makers address failure markets account for services; examination valuing and, hence, understanding consequences decisions neglect these ways economists are currently incorporating decision models conservation management biodiversity. final new ecoinformatics help transform globally finally, advancements future directions field. book's ultimate conclusion is essential element any strategy sustainable development.

Язык: Английский

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A Graphical Model of Keystone Predators in Food Webs: Trophic Regulation of Abundance, Incidence, and Diversity Patterns in Communities

The American Naturalist, Год журнала: 1996, Номер 147(5), С. 784 - 812

Опубликована: Май 1, 1996

I analyze a model of species interactions involving that compete for single resource and share common "keystone predator" to study the "bottom-up" effects productivity (potential carrying capacity resource) "top-down" factors affect death rate predator on diversity, abundance, distribution patterns in resulting assemblages. The predicts coexistence such will occur at intermediate (and rates top predator) superior exploiters dominate low high rates), whereas predator-resistant forms rates). In this model, densities are "buffered" against variation productivity, but trophic level not. Given large "pool" potential species, replacement series multiple pairs ranging from good as increases or decrease. case, is most likely among more similar forms, abundances predicted be negatively correlated. Furthermore, overall density organisms all levels correlated with productivity. Spatiotemporal heterogeneity modifies these predictions by allowing than two coexist presence permitting positive covariation coexisting competitors well. These models show critical role compositional turnover determining food web responses bottom-up top-down regulation rates. also predict unimodal diversity versus curves depend part degree prey specificity predator.

Язык: Английский

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Biodiversity in a complex world: consolidation and progress in functional biodiversity research

Ecology Letters, Год журнала: 2009, Номер 12(12), С. 1405 - 1419

Опубликована: Окт. 22, 2009

Ecology Letters (2009) 12: 1405–1419 Abstract The global decline of biodiversity caused by human domination ecosystems worldwide is supposed to alter important process rates and state variables in these ecosystems. However, there considerable debate on the prevalence importance effects ecosystem function (BDEF). Here, we argue that much stems from two major shortcomings. First, most studies do not directly link traits leading increased or decreased needed for species coexistence dominance. We implementing a trait‐based approach broadening perception diversity include trait dissimilarity divergence will result more realistic predictions consequences altered biodiversity. Second, empirical theoretical reflect complexity natural ecosystems, which makes it difficult transfer results situations loss. review how different aspects (trophic structure, multifunctionality, spatial temporal heterogeneity, population dynamics) our BDEF. propose future research avenues concisely testing whether acknowledging this strengthen observed effects. Finally, task disentangle direct changes due alterations abiotic constraints.

Язык: Английский

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