The topology of spatial networks affects stability in experimental metacommunities

Arancibia, Paulina1

Published Apr 22, 2024 on Dryad. https://doi.org/10.5061/dryad.brv15dvgc

Data files

Apr 22, 2024 version files 27.39 KB

Abstract

Understanding the drivers of community stability has been a central goal in ecology. Traditionally the emphasis has been placed on studying the effects of biotic interactions on community variability, and less is understood about how the spatial configuration of habitats promotes or hinders metacommunity stability. To test the effects of contrasting spatial configurations on metacommunity stability, I designed metacommunities with patches connected as random or scale-free networks. In these microcosms, two prey and one protist predator dispersed, and I evaluated community persistence, tracked biomass variations, and measured synchrony between local communities and their neighbors. After 30 generations, scale-free metacommunities had lower global biomass variability and higher persistence, suggesting higher stability. At the local scale, patches in scale-free metacommunities showed a positive relationship between variability and patch connectivity, indicating higher stability in isolated communities. No clear relationship was observed in random networks. These results suggest the increased heterogeneity in connectivity of scale-free networks favors the prevalence of isolated patches in the metacommunity, which likely act as refugia against competition—the most dominant interaction in this system—resulting in higher global stability. These results highlight the importance of accounting for network topology in the study of spatial dynamics.

README: The topology of spatial networks affects stability in experimental metacommunities

https://doi.org/10.5061/dryad.brv15dvgc

Biomass data was used to calculate the coefficient of variation (CV) at the meta-community level and local community level.

File structure

biomass_variation.csv: raw community biomass

net_name: identification of network-level replicates
network: type of network topology
plate: identification of meta community-level replicates
day: time

cv_per_spp.csv: CV calculated separately for each species at the meta-community level

net_name: identification of network-level replicates
network: type of network topology
plate: identification of meta community-level replicates
p_cv: CV of Paramecium tetraurelia
pb_cv: CV of Paramecium bursaria
dil_cv: CV of Dileptus anser

data_for_local_cv.csv: CV of biomass calculated at the local community level (i.e., patch)

net_name: identification of network-level replicates
network: type of network topology
plate: identification of meta community-level replicates
node: local habitat patch
degree: patch metric describing the number of direct neighbors connected to the focal patch
closenesscent: the measure of closeness centrality. This patch metric describes how "central" a habitat patch is, calculated on the reciprocal of the average shortest path length between the focal patch and all other patches in the network.
local_cv: calculation of the CV of biomass in that focal patch throughout the experiment.

MC-wide_CV.csv: CV of community biomass at the meta-community level

net_name: identification of network-level replicates
network: type of network topology
plate: identification of meta community-level replicates
global: CV of community biomass at the meta-community level

Persistence.csv: persistence data for the three species at the meta-community (plate) level

net_name: identification of network-level replicates
network: type of network topology
plate: identification of meta-community-level replicates
species: species identity
days_until_ext: number of days that species was recorded as present in the experiment
full_comm_span: number of days where all three species were recorded as present in the experiment