Ecological Networks Across Environmental Gradients

Abstract

Ecological networks have a long history in ecology, and a recent increase in network analyses across environmental gradients has revealed important changes in their structure, dynamics, and functioning. These changes can be broadly grouped according to three nonexclusive mechanisms: (a) changes in the species composition of the networks (driven by interaction patterns of invaders, nonrandom extinction of species according to their traits, or differences among species in population responses across gradients); (b) changes that alter interaction frequencies via changes in search efficiency (driven by altered habitat structure or metabolic rates) or changes in spatial and temporal overlap; and (c) changes to coevolutionary processes and patterns. Taking spatial and temporal processes into account can further elucidate network variation and improve predictions of network responses to environmental change. Emerging evidence links network structure to ecosystem functioning; however, scaling up to metanetworks or multilayer networks may modify interpretations of network structure, stability, and functioning.