Effects of time-varying habitat connectivity on metacommunity persistence

TL;DR

This study investigates how time-varying network connectivity influences species synchronization and persistence in ecological metacommunities, revealing that dynamic rewiring can promote asynchrony and enhance species survival.

Contribution

It introduces a model of time-varying small-world networks with chaotic food chain oscillators, showing how rewiring patterns affect synchronization and species persistence.

Findings

Higher rewiring probabilities induce asynchrony in networks.

Small rewiring periods with higher connectivity promote asynchrony and species persistence.

Synchronization time calculations are consistent across different ecosystem models.

Abstract

Network structure or connectivity pattern is critical in determining collective dynamics among interacting species in ecosystems. Conventional research on species persistence in spatial populations has focused on static network structure, though most real network structures change in time, forming time-varying networks. This raises the question, in metacommunities, how does the pattern of synchrony vary with temporal evolution in the network structure. The synchronous dynamics among species are known to reduce metacommunity persistence. Here, we consider a time-varying metacommunity small-world network consisting of a chaotic three-species food chain oscillator in each patch/node. The rate of change in the network connectivity is determined by the natural frequency or its subharmonics of the constituent oscillator to allow sufficient time for the evolution of species in between successive rewirings. We find that over a range of coupling strengths and rewiring periods, even higher rewiring probabilities drive a network from asynchrony towards synchrony. Moreover, in networks with a small rewiring period, an increase in average degree (more connected networks) pushes the asynchronous dynamics to synchrony. On the contrary, in networks with a low average degree, a higher rewiring period drives the synchronous dynamics to asynchrony resulting in increased species persistence. Our results also follow the calculation of synchronization time and robust across other ecosystem models. Overall, our study opens the possibility of developing temporal connectivity strategies to increase species persistence in ecological networks.