scholarly journals Coexistence patterns and diversity in a trait-based metacommunity on an environmental gradient

2021 ◽  
Author(s):  
Mozzamil Mohammed ◽  
Bernd Blasius ◽  
Alexey Ryabov
Keyword(s):  
Environmental Gradient ◽  
Resource Competition ◽  
Environmental Variability ◽  
Environmental Filtering ◽  
Dispersal Rate ◽  
Optimal Position ◽  
Joint Influence ◽  
Coexistence Mechanisms ◽  
Source Sink ◽  
Resource Variability

The dynamics of trait-based metacommunities have attracted much attention, but not much is known about how dispersal and environmental variability mutually interact with each other to drive coexistence mechanisms and diversity patterns. Here, we present a spatially-explicit model of resource competition in a metacommunity on a one-dimensional environmental gradient and analyse the joint influence of dispersal and environmental variability on coexistence mechanisms, spatial structure, trait distribution and local and regional diversity. We find that without dispersal, species are sorted according to their optimal position on the gradient, but with the onset of dispersal source-sink effects are initiated. Thereby, the dispersal rate and the range of spatial environmental variability strongly affect the competition outcomes, composition, and diversity. That is, at low dispersal rates the number of surviving species increases with the spatial environmental variability. Increasing dispersal rates generates trait lumping and strengthens environmental filtering so that only a few dominant species can survive. Interestingly, for very large dispersal rates the system becomes spatially homogeneous, but nevertheless two specialists at the extreme ends of the trait-off curve can coexist. Global species richness depends in an intricate manner on dispersal strength and resource variability, with a classic hump-shaped dependence of diversity on dispersal rate, but also a pronounced peak of global diversity for intermediate values of resource variability. Our findings thus provide important insights into the factors that shape metacommunity structure and promote coexistence and about how spatial environmental variability can lead to different competition outcomes in metacommunities.

scholarly journals Coexistence Patterns and Diversity in A Trait-Based Metacommunity On An Environmental Gradient

2021 ◽  
Author(s):  
Mozzamil Mohammed ◽  
Bernd Blasius ◽  
Alexey Ryabov
Keyword(s):  
Environmental Gradient ◽  
Resource Competition ◽  
Environmental Variability ◽  
Environmental Filtering ◽  
Optimal Growth ◽  
Growth Conditions ◽  
Regional Diversity ◽  
Local Species Richness ◽  
Local Species ◽  
Source Sink

Abstract The dynamics of trait-based metacommunities have attracted much attention, but not much is known about how dispersal and spatial environmental variability mutually interact with each other to drive coexistence patterns and diversity. Here, we present a spatially-explicit model of resource competition in a metacommunity on a one- dimensional environmental gradient. We find that both the strength of dispersal and the range of spatial environmental variability affect coexistence patterns, spatial structure, trait distribution and local and regional diversity. Without dispersal, species are sorted according to their optimal growth conditions on the gradient. With the onset of dispersal source-sink effects are initiated, which increases the effects of environmental filtering and interspecific competition and generates trait lumping, so that only a few species from an environment-defined trait range can survive. Interestingly, for very large dispersal rates the system becomes spatially homogeneous, but nevertheless two species at the extreme ends of the trait-off curve can coexist for large environmental variability. Local species richness follows a classic hump-shaped dependence on dispersal rate, while local and regional diversity exhibit a pronounced peak for intermediate values of the environmental variability. Our findings provide important insights into the factors that shape the structure of trait-based metacommunities.

scholarly journals Coexistence patterns and diversity in a trait-based metacommunity on an environmental gradient

2022 ◽  
Author(s):  
Mozzamil Mohammed ◽  
Bernd Blasius ◽  
Alexey Ryabov
Keyword(s):  
Environmental Gradient ◽  
Environmental Variability ◽  
Environmental Filtering ◽  
Optimal Growth ◽  
Growth Conditions ◽  
Spatially Explicit Model ◽  
Regional Diversity ◽  
Local Species Richness ◽  
Local Species ◽  
Source Sink

AbstractThe dynamics of trait-based metacommunities have attracted much attention, but not much is known about how dispersal and spatial environmental variability mutually interact with each other to drive coexistence patterns and diversity. Here, we present a spatially explicit model of competition for two essential resources in a metacommunity on a one-dimensional environmental gradient. We find that both the strength of dispersal and the range of spatial environmental variability affect coexistence patterns, spatial structure, trait distribution, and local and regional diversity. Without dispersal, species are sorted according to their optimal growth conditions on the gradient. With the onset of dispersal, source-sink effects are initiated, which increases the effects of environmental filtering and interspecific competition and generates trait lumping, so that only a few species from an environment-defined trait range can survive. Interestingly, for very large dispersal rates, species distributions become spatially homogeneous, but nevertheless two species at the extreme ends of the trade-off curve can coexist for large environmental variability. Local species richness follows a classic hump-shaped dependence on dispersal rate, while local and regional diversity exhibit a pronounced peak for intermediate values of the environmental variability. Our findings provide important insights into the factors that shape the structure of trait-based metacommunities.

scholarly journals Environment drives high phylogenetic turnover among oceanic bacterial communities

2012 ◽  
Vol 8 (4) ◽  
pp. 562-566 ◽  
Author(s):  
Thomas Pommier ◽  
Emmanuel J. P. Douzery ◽  
David Mouillot
Keyword(s):  
Bacterial Communities ◽  
Environmental Gradient ◽  
Regional Scale ◽  
Environmental Filtering ◽  
Species Level ◽  
Geographical Distance ◽  
Abiotic Conditions ◽  
High Connectivity ◽  
Phylogenetic Lineages ◽  
Marine Microbial Communities

Although environmental filtering has been observed to influence the biodiversity patterns of marine bacterial communities, it was restricted to the regional scale and to the species level, leaving the main drivers unknown at large biogeographic scales and higher taxonomic levels. Bacterial communities with different species compositions may nevertheless share phylogenetic lineages, and phylogenetic turnover (PT) among those communities may be surprisingly low along any biogeographic or environmental gradient. Here, we investigated the relative influence of environmental filtering and geographical distance on the PT between marine bacterial communities living more than 8000 km apart in contrasted abiotic conditions. PT was high between communities and was more structured by local environmental factors than by geographical distance, suggesting the predominance of a lineage filtering process. Strong phenotype-environment mismatches observed in the ocean may surpass high connectivity between marine microbial communities.

Resource variability and the collapse of a dominance hierarchy in a colour polymorphic species

Behaviour ◽  
2018 ◽  
Vol 155 (6) ◽  
pp. 443-463 ◽  
Author(s):  
Dawson M. Brown ◽  
Matthew S. Lattanzio
Keyword(s):  
Social Dominance ◽  
Dominance Hierarchy ◽  
Environmental Variability ◽  
Behavioural Flexibility ◽  
Dominance Hierarchies ◽  
Species Dominance ◽  
Polymorphic Species ◽  
Series Of Experiments ◽  
Colour Morphs ◽  
Resource Variability

Abstract Intraspecific social dominance hierarchies should be influenced by environmental variation; however, in colour polymorphic species, dominance hierarchies are often assumed fixed, and thus insensitive to environmental variability. We ran a series of experiments using the colour polymorphic long-tailed brush lizard (Urosaurus graciosus) to challenge this assumption. We staged contests between orange and yellow morph males over a single heated perch, two perches at the same temperature, or two perches differing in temperature. Our first experiment revealed that orange-throated males are socially dominant. However, this hierarchy collapsed in our other experiments as yellow males became more aggressive. Interestingly, both males only ever secured their own perch where the perches differed in temperature. These findings mirror observations of morph behavioural flexibility in nature and studies of behaviour–environment interactions in non-polymorphic taxa. We conclude that colour morphs may have an underappreciated ability to assess resource-level changes and respond with concomitant flexibility in behaviour.

scholarly journals A minimal model for microbial biodiversity can reproduce experimentally observed ecological patterns

2019 ◽  
Author(s):  
Robert Marsland ◽  
Wenping Cui ◽  
Pankaj Mehta
Keyword(s):  
Minimal Model ◽  
Large Scale ◽  
Resource Competition ◽  
Human Microbiome ◽  
Environmental Filtering ◽  
Energetic Cost ◽  
Minimal Models ◽  
Microbial Biodiversity ◽  
Ecological Processes ◽  
Ecological Patterns

AbstractSurveys of microbial biodiversity such as the Earth Microbiome Project (EMP) and the Human Microbiome Project (HMP) have revealed robust ecological patterns across different environments. A major goal in ecology is to leverage these patterns to identify the ecological processes shaping microbial ecosystems. One promising approach is to use minimal models that can relate mechanistic assumptions at the microbe scale to community-level patterns. Here, we demonstrate the utility of this approach by showing that the Microbial Consumer Resource Model (MiCRM) – a minimal model for microbial communities with resource competition, metabolic crossfeeding and stochastic colonization – can qualitatively reproduce patterns found in survey data including compositional gradients, dissimilarity/overlap correlations, richness/harshness correlations, and nestedness of community composition. By using the MiCRM to generate synthetic data with different environmental and taxonomical structure, we show that large scale patterns in the EMP can be reproduced by considering the energetic cost of surviving in harsh environments and HMP patterns may reflect the importance of environmental filtering in shaping competition. We also show that recently discovered dissimilarity-overlap correlations in the HMP likely arise from communities that share similar environments rather than reflecting universal dynamics. We identify ecologically meaningful changes in parameters that alter or destroy each one of these patterns, suggesting new mechanistic hypotheses for further investigation. These findings highlight the promise of minimal models for microbial ecology.

scholarly journals The relationship between species richness and ecosystem variability is shaped by the mechanism of coexistence

2017 ◽  
Author(s):  
Andrew T. Tredennick ◽  
Peter B. Adler ◽  
Frederick R. Adler
Keyword(s):  
Species Richness ◽  
Species Coexistence ◽  
Environmental Variability ◽  
Storage Effect ◽  
Natural Gradient ◽  
Species Pools ◽  
Coexistence Mechanisms ◽  
The Relationship ◽  
General Explanation ◽  
Consumer Resource

AbstractTheory relating species richness to ecosystem variability typically ignores the potential for environmental variability to promote species coexistence. Failure to account for fluctuation-dependent coexistence mechanisms may explain observed deviations from the expected negative diversity–ecosystem variability relationship, and limits our ability to predict the consequences of future increases in environmental variability. We use a consumer-resource model to explore how coexistence via the temporal storage effect and relative nonlinearity affects ecosystem variability. We show that a positive, rather than negative, diversity–ecosystem variability relationship is possible when ecosystem function is sampled across a natural gradient in environmental variability and diversity. We also show how fluctuation-dependent coexistence can buffer ecosystem functioning against increasing environmental variability by promoting species richness and portfolio effects. Our work provides a general explanation for variation in observed diversity–ecosystem variability relationships and highlights the importance of conserving regional species pools to help buffer ecosystems against predicted increases in environmental variability.

scholarly journals Assessing metacommunity processes through signatures in spatiotemporal turnover of community composition

2018 ◽  
Author(s):  
Franck Jabot ◽  
Fabien Laroche ◽  
François Massol ◽  
Florent Arthaud ◽  
Julie Crabot ◽  
...  
Keyword(s):  
Environmental Variability ◽  
Temporal Dynamics ◽  
Environmental Filtering ◽  
Analytical Framework ◽  
Temporal Part ◽  
Ecological Processes ◽  
Metacommunity Ecology ◽  
Path Analyses ◽  
Metacommunity Dynamics ◽  
Acting In Concert

AbstractAlthough metacommunity ecology has been a major field of research in the last decades, with both conceptual and empirical outputs, the analysis of the temporal dynamics of metacommunities has only emerged recently and consists mostly of repeated static analyses. Here, we propose a novel analytical framework to assess metacommunity processes using path analyses of spatial and temporal diversity turnovers. We detail the principles and practical aspects of this framework and apply it to simulated datasets to illustrate its ability to decipher the respective contributions of entangled drivers of metacommunity dynamics. We then apply it to four empirical datasets. Empirical results support the view that metacommunity dynamics may be generally shaped by multiple ecological processes acting in concert, with environmental filtering being variable across both space and time. These results reinforce our call to go beyond static analyses of metacommunities that are blind to the temporal part of environmental variability.

scholarly journals Robustness of norm-driven cooperation in the commons

2016 ◽  
Vol 283 (1822) ◽  
pp. 20152431 ◽  
Author(s):  
Maja Schlüter ◽  
Alessandro Tavoni ◽  
Simon Levin
Keyword(s):  
Global Change ◽  
Environmental Variability ◽  
Sustainable Use ◽  
Community Members ◽  
Large Variability ◽  
Self Organized ◽  
Sustainable Resource Use ◽  
Optimal Resource ◽  
The Commons ◽  
Resource Variability

Sustainable use of common-pool resources such as fish, water or forests depends on the cooperation of resource users that restrain their individual extraction to socially optimal levels. Empirical evidence has shown that under certain social and biophysical conditions, self-organized cooperation in the commons can evolve. Global change, however, may drastically alter these conditions. We assess the robustness of cooperation to environmental variability in a stylized model of a community that harvests a shared resource. Community members follow a norm of socially optimal resource extraction, which is enforced through social sanctioning. Our results indicate that both resource abundance and a small increase in resource variability can lead to collapse of cooperation observed in the no-variability case, while either scarcity or large variability have the potential to stabilize it. The combined effects of changes in amount and variability can reinforce or counteract each other depending on their size and the initial level of cooperation in the community. If two socially separate groups are ecologically connected through resource leakage, cooperation in one can destabilize the other. These findings provide insights into possible effects of global change and spatial connectivity, indicating that there is no simple answer as to their effects on cooperation and sustainable resource use.

scholarly journals Non-random distribution of individual genetic diversity along an environmental gradient

2009 ◽  
Vol 364 (1523) ◽  
pp. 1543-1554 ◽  
Author(s):  
Mélody Porlier ◽  
Marc Bélisle ◽  
Dany Garant
Keyword(s):  
Genetic Diversity ◽  
Environmental Gradient ◽  
Environmental Changes ◽  
Environmental Variability ◽  
Ecological Factors ◽  
Tree Swallows ◽  
Factors Affecting ◽  
Individual Level ◽  
Breeding Grounds ◽  
The Individual

Improving our knowledge of the links between ecology and evolution is especially critical in the actual context of global rapid environmental changes. A critical step in that direction is to quantify how variation in ecological factors linked to habitat modifications might shape observed levels of genetic variability in wild populations. Still, little is known on the factors affecting levels and distribution of genetic diversity at the individual level, despite its vital underlying role in evolutionary processes. In this study, we assessed the effects of habitat quality on population structure and individual genetic diversity of tree swallows ( Tachycineta bicolor ) breeding along a gradient of agricultural intensification in southern Québec, Canada. Using a landscape genetics approach, we found that individual genetic diversity was greater in poorer quality habitats. This counter-intuitive result was partly explained by the settlement patterns of tree swallows across the landscape. Individuals of higher genetic diversity arrived earlier on their breeding grounds and settled in the first available habitats, which correspond to intensive cultures. Our results highlight the importance of investigating the effects of environmental variability on individual genetic diversity, and of integrating information on landscape structure when conducting such studies.

scholarly journals Wood structure explained by complex spatial source-sink interactions

2020 ◽  
Author(s):  
Andrew D. Friend
Keyword(s):  
Environmental Variability ◽  
High Sensitivity ◽  
Wood Formation ◽  
Current Theory ◽  
Strength Properties ◽  
Wall Thickening ◽  
Diverse Range ◽  
Latewood Density ◽  
Increasing Temperature ◽  
Source Sink

AbstractWood is a remarkable material. It is responsible for the sequestration of significant anthropogenic CO21, aids understanding of past climates2, has unique acoustic, thermal, and strength properties, and is an endlessly renewable source of energy3. However, we lack a general integrated understanding of how its structure is created. A theoretical framework of wood formation is presented here that explains a diverse range of poorly understood observations, including: (i) the anatomy of growth rings, with a transition from low-density earlywood to high-density latewood; (ii) the high sensitivity of latewood density to temperature; (iii) cell-size regulation; and (iv) relationships between growth and temperature. These features arise from interactions in time and space between the production of cells, the dynamics of developmental zones, and the supply of carbohydrates. Carbohydrate distribution is critical for the final density profile, challenging current theory which emphasises compensation between the rates and durations of cell enlargement and wall thickening. These findings have implications for our understanding of how growth responds to environmental variability and the interpretation of tree rings as proxies of past climates. In addition, they provide a framework for the incorporation of explicit growth processes into models, such as those used to predict the role of vegetation in the future global carbon cycle. Finally, divergent responses in volume and mass with increasing temperature suggest caution in interpreting observations based on volume alone.

Sign in / Sign up

Export Citation Format

Share Document