title: Bottom-up effects of plant diversity on multitrophic interactions in a biodiversity experiment.
abstract: Biodiversity is rapidly declining, and this may negatively affect ecosystem processes, including economically important ecosystem services. Previous studies have shown that biodiversity has positive effects on organisms and processes across trophic levels. However, only a few studies have so far incorporated an explicit food-web perspective. In an eight-year biodiversity experiment, we studied an unprecedented range of above- and below-ground organisms and multitrophic interactions. A multitrophic data set originating from a single long-term experiment allows mechanistic insights that would not be gained from meta-analysis of different experiments. Here we show that plant diversity effects dampen with increasing trophic level and degree of omnivory. This was true both for abundance and species richness of organisms. Furthermore, we present comprehensive above-ground/below-ground biodiversity food webs. Both above ground and below ground, herbivores responded more strongly to changes in plant diversity than did carnivores or omnivores. Density and richness of carnivorous taxa was independent of vegetation structure. Below-ground responses to plant diversity were consistently weaker than above-ground responses. Responses to increasing plant diversity were generally positive, but were negative for biological invasion, pathogen infestation and hyperparasitism. Our results suggest that plant diversity has strong bottom-up effects on multitrophic interaction networks, with particularly strong effects on lower trophic levels. Effects on higher trophic levels are indirectly mediated through bottom-up trophic cascades.
authors.affiliation: Georg-August-University Göttingen, Department of Crop Sciences, Agroecology, Grisebachstrasse 6, 37077 Göttingen, Germany. christoph.scherber@agr.uni-goettingen.de
authors.forename: Christoph
authors.initials: C
authors.lastname: Scherber
authors.forename: Nico
authors.initials: N
authors.lastname: Eisenhauer
authors.forename: Wolfgang W
authors.initials: WW
authors.lastname: Weisser
authors.forename: Bernhard
authors.initials: B
authors.lastname: Schmid
authors.forename: Winfried
authors.initials: W
authors.lastname: Voigt
authors.forename: Markus
authors.initials: M
authors.lastname: Fischer
authors.forename: Ernst-Detlef
authors.initials: ED
authors.lastname: Schulze
authors.forename: Christiane
authors.initials: C
authors.lastname: Roscher
authors.forename: Alexandra
authors.initials: A
authors.lastname: Weigelt
authors.forename: Eric
authors.initials: E
authors.lastname: Allan
authors.forename: Holger
authors.initials: H
authors.lastname: Bessler
authors.forename: Michael
authors.initials: M
authors.lastname: Bonkowski
authors.forename: Nina
authors.initials: N
authors.lastname: Buchmann
authors.forename: François
authors.initials: F
authors.lastname: Buscot
authors.forename: Lars W
authors.initials: LW
authors.lastname: Clement
authors.forename: Anne
authors.initials: A
authors.lastname: Ebeling
authors.forename: Christof
authors.initials: C
authors.lastname: Engels
authors.forename: Stefan
authors.initials: S
authors.lastname: Halle
authors.forename: Ilona
authors.initials: I
authors.lastname: Kertscher
authors.forename: Alexandra-Maria
authors.initials: AM
authors.lastname: Klein
authors.forename: Robert
authors.initials: R
authors.lastname: Koller
authors.forename: Stephan
authors.initials: S
authors.lastname: König
authors.forename: Esther
authors.initials: E
authors.lastname: Kowalski
authors.forename: Volker
authors.initials: V
authors.lastname: Kummer
authors.forename: Annely
authors.initials: A
authors.lastname: Kuu
authors.forename: Markus
authors.initials: M
authors.lastname: Lange
authors.forename: Dirk
authors.initials: D
authors.lastname: Lauterbach
authors.forename: Cornelius
authors.initials: C
authors.lastname: Middelhoff
authors.forename: Varvara D
authors.initials: VD
authors.lastname: Migunova
authors.forename: Alexandru
authors.initials: A
authors.lastname: Milcu
authors.forename: Ramona
authors.initials: R
authors.lastname: Müller
authors.forename: Stephan
authors.initials: S
authors.lastname: Partsch
authors.forename: Jana S
authors.initials: JS
authors.lastname: Petermann
authors.forename: Carsten
authors.initials: C
authors.lastname: Renker
authors.forename: Tanja
authors.initials: T
authors.lastname: Rottstock
authors.forename: Alexander
authors.initials: A
authors.lastname: Sabais
authors.forename: Stefan
authors.initials: S
authors.lastname: Scheu
authors.forename: Jens
authors.initials: J
authors.lastname: Schumacher
authors.forename: Vicky M
authors.initials: VM
authors.lastname: Temperton
authors.forename: Teja
authors.initials: T
authors.lastname: Tscharntke
mesh_terms: D000818:Animals; D044822:Biodiversity; D008954:Models, Biological; D018521:Plant Physiological Phenomena; D011156:Population Density