Simulating the role of connectivity in shaping stream insect metacommunities under colonization cycle dynamics

• Published in: Ecological modelling 2016-08, Vol.334, p.19-26
• Main Authors: Durães, Lucas, Roque, Fabio O., Siqueira, Tadeu, Santos, Anderson M., Borges, Magno A., Rezende, Renan S.
• Format: Article
• Language: English
• Subjects: adults; Aquatic insects; Assembly; Assembly rules; Computer simulation; Connectivity; Dendritic networks; Dispersal limitation; Dispersion; Ecology; environmental factors; Filtering; flight; freshwater; Graphical representations; habitats; Insects; larvae; monitoring; Networks; oviposition; species diversity; streams
• ISSN: 0304-3800; 1872-7026
• DOI: 10.1016/j.ecolmodel.2016.04.020

•Our model shows that dendritic pattern of riverine networks is important drive to local species richness of metacommunities in niche-assembled and dispersal-assembled scenarios.•The role of connectivity in shaping riverine metacommunities is context-dependent, that is, it depends on factors such as dispersal ability, environmental filtering and stochastic process.•The spatial structure of riverine networks should be considered in monitoring and conservation of freshwater biota. We simulated metacommunities in a hypothetical riverine network to investigate whether and how connectivity affects the species richness of groups with different dispersal abilities under different niche- and dispersal-assembly rules. The simulated network was represented by a graph in which the nodes represented habitat patches, each with a particular environmental condition. We built our model based on Müller's “colonization cycle” hypothesis, in which adult aquatic insects compensate for the gradual downstream movement of larvae by flying preferentially upstream to oviposition. Species occurrence in each patch was probabilistically determined, taking into account environmental filtering and/or dispersal ability in different assembly scenarios. Variation in local species richness was explained by connectivity in both assembly scenarios, especially when dispersal ability was weak. In niche assembly metacommunities, the effect of connectivity was also dependent on the location of preferable patches. In general, local species richness was higher when dispersal ability was strong. Our findings suggest that the role of connectivity in shaping riverine metacommunities is context dependent and that the spatial structure of riverine networks should be considered in monitoring freshwater biota.