title: Ecosystem engineering effects on species diversity across ecosystems: a meta-analysis.
abstract: Ecosystem engineering is increasingly recognized as a relevant ecological driver of diversity and community composition. Although engineering impacts on the biota can vary from negative to positive, and from trivial to enormous, patterns and causes of variation in the magnitude of engineering effects across ecosystems and engineer types remain largely unknown. To elucidate the above patterns, we conducted a meta-analysis of 122 studies which explored effects of animal ecosystem engineers on species richness of other organisms in the community. The analysis revealed that the overall effect of ecosystem engineers on diversity is positive and corresponds to a 25% increase in species richness, indicating that ecosystem engineering is a facilitative process globally. Engineering effects were stronger in the tropics than at higher latitudes, likely because new or modified habitats provided by engineers in the tropics may help minimize competition and predation pressures on resident species. Within aquatic environments, engineering impacts were stronger in marine ecosystems (rocky shores) than in streams. In terrestrial ecosystems, engineers displayed stronger positive effects in arid environments (e.g. deserts). Ecosystem engineers that create new habitats or microhabitats had stronger effects than those that modify habitats or cause bioturbation. Invertebrate engineers and those with lower engineering persistence (<1 year) affected species richness more than vertebrate engineers which persisted for >1 year. Invertebrate species richness was particularly responsive to engineering impacts. This study is the first attempt to build an integrative framework of engineering effects on species diversity; it highlights the importance of considering latitude, habitat, engineering functional group, taxon and persistence of their effects in future theoretical and empirical studies.
authors.affiliation: Departamento de Biologia Animal, Instituto de Biologia, Universidade Estadual de Campinas (UNICAMP), CP 6109, CEP 13083-970 Campinas, São Paulo, Brazil.
authors.forename: Gustavo Q
authors.initials: GQ
authors.lastname: Romero
authors.affiliation: Departamento de Biologia Animal, Instituto de Biologia, Universidade Estadual de Campinas (UNICAMP), CP 6109, CEP 13083-970 Campinas, São Paulo, Brazil.
authors.forename: Thiago
authors.initials: T
authors.lastname: Gonçalves-Souza
authors.affiliation: Graduate Course in Ecology, Instituto de Biologia, Universidade Estadual de Campinas (UNICAMP), CP 6109, CEP 13083-970 Campinas, São Paulo, Brazil.
authors.forename: Camila
authors.initials: C
authors.lastname: Vieira
authors.affiliation: School of Biological Sciences, Royal Holloway University of London, Egham, Surrey TW20 0EX, U.K.
authors.forename: Julia
authors.initials: J
authors.lastname: Koricheva
mesh_terms: D000818:Animals; D044822:Biodiversity; D017753:Ecosystem; D004777:Environment; D007448:Invertebrates / Q000502:physiology; D011235:Predatory Behavior; D014714:Vertebrates / Q000502:physiology
keywords: diversity; ecosystem engineers; facilitation; functional group; indirect interactions; metafor; meta‐analysis; richness; tropical versus temperate; ‘stress‐gradient hypothesis’