title: The extent of functional redundancy changes as species' roles shift in different environments.
abstract: Assessing the ecological impacts of environmental change requires knowledge of the relationship between biodiversity and ecosystem functioning. The exact nature of this relationship can differ considerably between ecosystems, with consequences for the efficacy of species diversity as a buffer against environmental change. Using a microbial model system, we show that the relationship can vary depending on environmental conditions. Shapes suggesting functional redundancy in one environment can change, suggesting functional differences in another environment. We find that this change is due to shifting species roles and interactions. Species that are functionally redundant in one environment may become pivotal in another. Thus, caution is advised in drawing conclusions about functional redundancy based on a single environmental situation. It also implies that species richness is important because it provides a pool of species with potentially relevant traits. These species may turn out to be essential performers or partners in new interspecific interactions after environmental change. Therefore, our results challenge the generality of functional redundancy.
authors.affiliation: Department of Environmental Microbiology, Helmholtz Centre for Environmental Research-UFZ, 04318 Leipzig, Germany; Stockholm Resilience Centre, Stockholm University, 11419 Stockholm, Sweden;
authors.forename: Ingo
authors.initials: I
authors.lastname: Fetzer
authors.affiliation: Department of Ecological Modelling, Helmholtz Centre for Environmental Research-UFZ, 04318 Leipzig, Germany;
authors.forename: Karin
authors.initials: K
authors.lastname: Johst
authors.affiliation: Department of Environmental Microbiology, Helmholtz Centre for Environmental Research-UFZ, 04318 Leipzig, Germany;
authors.forename: Robert
authors.initials: R
authors.lastname: Schäwe
authors.affiliation: Department of Ecological Modelling, Helmholtz Centre for Environmental Research-UFZ, 04318 Leipzig, Germany;
authors.forename: Thomas
authors.initials: T
authors.lastname: Banitz
authors.affiliation: Department of Environmental Microbiology, Helmholtz Centre for Environmental Research-UFZ, 04318 Leipzig, Germany; German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, 04103 Leipzig, Germany.
authors.forename: Hauke
authors.initials: H
authors.lastname: Harms
authors.affiliation: Department of Environmental Microbiology, Helmholtz Centre for Environmental Research-UFZ, 04318 Leipzig, Germany; German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, 04103 Leipzig, Germany antonis.chatzinotas@ufz.de.
authors.forename: Antonis
authors.initials: A
authors.lastname: Chatzinotas
mesh_terms: D001419:Bacteria / Q000254:growth & development*; D059013:Microbial Consortia / Q000502:physiology*; D008954:Models, Biological
keywords: biodiversity-ecosystem functioning; environmental change; functional redundancy; microbial model system; species interactions