Metacommunity organisation, spatial extent and dispersal in aquatic systems: patterns, processes and prospects

Freshwater Biology, Journal Year: 2014, Volume and Issue: 60(5), P. 845 - 869

Published: Dec. 29, 2014

Summary Metacommunity ecology addresses the situation where sets of local communities are connected by dispersal a number potentially interacting species. Aquatic systems (e.g. lentic versus lotic marine) differ from each other in connectivity and environmental heterogeneity, suggesting that metacommunity organisation also differs between major aquatic systems. Here, we review findings observational field studies on Species sorting (i.e. species ‘filtered’ factors occur only at environmentally suitable sites) prevails systems, particularly streams lakes, but degree to which limitation interacts with such control varies among different spatial scales. For example, mainstem rivers marine coastal may be strongly affected ‘mass effects’ high rates homogenise some neighbouring localities, irrespective their abiotic biotic conditions), whereas isolated lakes ponds structured do not otherwise‐suitable localities simply because sites potential colonists too far away). Flow directionality running waters water movements this difference have effects role Dispersal typically increases increasing distance sites, mass increase importance decreasing ability organisms determine extents processes most important. A better understanding relative roles sorting, affecting metacommunities requires following: (i) characterising more directly or adopting proxies than been used previously; (ii) considering nature networks; (iii) combining correlative experimental approaches; (iv) exploring temporal aspects (v) applying past approaches statistical methods innovatively for our organisation.

Language: Английский

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How to make more out of community data? A conceptual framework and its implementation as models and software

Ecology Letters, Journal Year: 2017, Volume and Issue: 20(5), P. 561 - 576

Published: March 20, 2017

Abstract Community ecology aims to understand what factors determine the assembly and dynamics of species assemblages at different spatiotemporal scales. To facilitate integration between conceptual statistical approaches in community ecology, we propose Hierarchical Modelling Species Communities ( HMSC ) as a general, flexible framework for modern analysis data. While non‐manipulative data allow only correlative not causal inference, this facilitates formulation data‐driven hypotheses regarding processes that structure communities. We model environmental filtering by variation covariation responses individual characteristics their environment, with potential contingencies on traits phylogenetic relationships. capture biotic rules species‐to‐species association matrices, which may be estimated multiple spatial or temporal operationalise hierarchical Bayesian joint distribution model, implement it R‐ Matlab‐packages enable computationally efficient analyses large sets. Armed tool, ecologists can make sense many types data, including spatially explicit time‐series illustrate use through series diverse ecological examples.

Language: Английский

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A consumer's guide to nestedness analysis

Oikos, Journal Year: 2008, Volume and Issue: 118(1), P. 3 - 17

Published: Dec. 23, 2008

Nestedness analysis has become increasingly popular in the study of biogeographic patterns species occurrence. Nested are those which composition small assemblages is a nested subset larger assemblages. For interaction networks such as plant–pollinator webs, nestedness also proven valuable tool for revealing ecological and evolutionary constraints. Despite this popularity, there been substantial controversy literature over best methods to define quantify nestedness, how test against an appropriate statistical null hypothesis. Here we review rapidly developing provide suggestions guidelines proper analyses. We focus on logic performance different metrics choice models inference. observe that traditional ‘gap‐counting’ biased towards loss among columns (occupied sites) many not invariant basic matrix properties. The should be combined with gradient infer possible causes observed presence–absence sequence. In our view, inference based model row sums fixed. Under model, only relatively number published empirical matrices significantly nested. call critical reassessment previous studies have used unconstrained

Language: Английский

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The microbiome of uncontacted Amerindians

Science Advances, Journal Year: 2015, Volume and Issue: 1(3)

Published: April 3, 2015

Most studies of the human microbiome have focused on westernized people with life-style practices that decrease microbial survival and transmission, or traditional societies are currently in transition to westernization. We characterize fecal, oral, skin bacterial resistome members an isolated Yanomami Amerindian village no documented previous contact Western people. These harbor a highest diversity bacteria genetic functions ever reported group. Despite their isolation, presumably for >11,000 years since ancestors arrived South America, known exposure antibiotics, they carry functional antibiotic resistance (AR) genes, including those confer synthetic antibiotics syntenic mobilization elements. results suggest westernization significantly affects AR genes appear be feature even absence commercial antibiotics. likely poised enrichment upon pharmacological levels Our findings emphasize need extensive characterization function remote nonwesternized populations before globalization modern potentially beneficial harbored body.

Language: Английский

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Estimating and mapping ecological processes influencing microbial community assembly

Frontiers in Microbiology, Journal Year: 2015, Volume and Issue: 6

Published: May 1, 2015

Ecological community assembly is governed by a combination of (i) selection resulting from among-taxa differences in performance; (ii) dispersal organismal movement; and (iii) ecological drift stochastic changes population sizes. The relative importance nature these processes can vary across environments. Selection be homogeneous or variable, while rate, we conceptualize extreme rates as two categories; limitation results limited exchange organisms among communities, homogenizing high levels organism exchange. To estimate the influence spatial variation each process extend recently developed statistical framework, use simulation model to evaluate accuracy extended framework examine subsurface microbial communities over geologic formations. For degree which it influenced selection, variable limitation, dispersal. Our analyses revealed that influences substantially even within formation. We further identify environmental features associated with process, allowed mapping ecological-process-influences. maps provide new lens through systems understood; system investigated here they was rate at redox conditions change depth.

Language: Английский

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