title: Invasive plants have different effects on trophic structure of green and brown food webs in terrestrial ecosystems: a meta-analysis.
abstract: Although invasive plants are a major source of terrestrial ecosystem degradation worldwide, it remains unclear which trophic levels above the base of the food web are most vulnerable to plant invasions. We performed a meta-analysis of 38 independent studies from 32 papers to examine how invasive plants alter major groupings of primary and secondary consumers in three globally distributed ecosystems: wetlands, woodlands and grasslands. Within each ecosystem we examined if green (grazing) food webs are more sensitive to plant invasions compared to brown (detrital) food webs. Invasive plants have strong negative effects on primary consumers (detritivores, bacterivores, fungivores, and/or herbivores) in woodlands and wetlands, which become less abundant in both green and brown food webs in woodlands and green webs in wetlands. Plant invasions increased abundances of secondary consumers (predators and/or parasitoids) only in woodland brown food webs and green webs in wetlands. Effects of invasive plants on grazing and detrital food webs clearly differed between ecosystems. Overall, invasive plants had the most pronounced effects on the trophic structure of wetlands and woodlands, but caused no detectable changes to grassland trophic structure.
authors.affiliation: Department of Biological Sciences, University of Illinois, Chicago, IL, 60607, USA.
authors.forename: Matthew A
authors.initials: MA
authors.lastname: McCary
authors.affiliation: Department of Biological Sciences, University of Illinois, Chicago, IL, 60607, USA.
authors.forename: Robin
authors.initials: R
authors.lastname: Mores
authors.affiliation: Department of Biological Sciences, University of Illinois, Chicago, IL, 60607, USA.
authors.forename: Monica A
authors.initials: MA
authors.lastname: Farfan
authors.affiliation: Department of Biological Sciences, University of Illinois, Chicago, IL, 60607, USA.|Institute for Environmental Science and Policy, University of Illinois, Chicago, IL, 60612, USA.
authors.forename: David H
authors.initials: DH
authors.lastname: Wise
mesh_terms: D020387:Food Chain; D065928:Forests; D065948:Grassland; D058865:Introduced Species; D018521:Plant Physiological Phenomena; D053833:Wetlands
keywords: Biodiversity; community structure; ecosystem function; exotic species; food web; invasion biology; invasive plants; literature review; meta-analysis; trophic level