title: Functional trait diversity across trophic levels determines herbivore impact on plant community biomass.
abstract: Understanding the consequences of trophic interactions for ecosystem functioning is challenging, as contrasting effects of species and functional diversity can be expected across trophic levels. We experimentally manipulated functional identity and diversity of grassland insect herbivores and tested their impact on plant community biomass. Herbivore resource acquisition traits, i.e. mandible strength and the diversity of mandibular traits, had more important effects on plant biomass than body size. Higher herbivore functional diversity increased overall impact on plant biomass due to feeding niche complementarity. Higher plant functional diversity limited biomass pre-emption by herbivores. The functional diversity within and across trophic levels therefore regulates the impact of functionally contrasting consumers on primary producers. By experimentally manipulating the functional diversity across trophic levels, our study illustrates how trait-based approaches constitute a promising way to tackle existing links between trophic interactions and ecosystem functioning.
authors.affiliation: UMR7372, Centre d'Etudes Biologiques de Chizé, CNRS-Université de La Rochelle, Villiers en Bois, 79360, Beauvoir sur Niort, France.|USC1339, Centre d'Etudes Biologiques de Chizé, INRA, Villiers en Bois, 79360, Beauvoir sur Niort, France.|LTER, ZA Plaine & Val de Sèvre, CNRS, 79360, Villiers en Bois, France.
authors.forename: Hélène
authors.initials: H
authors.lastname: Deraison
authors.affiliation: UMR7372, Centre d'Etudes Biologiques de Chizé, CNRS-Université de La Rochelle, Villiers en Bois, 79360, Beauvoir sur Niort, France.|USC1339, Centre d'Etudes Biologiques de Chizé, INRA, Villiers en Bois, 79360, Beauvoir sur Niort, France.|LTER, ZA Plaine & Val de Sèvre, CNRS, 79360, Villiers en Bois, France.
authors.forename: Isabelle
authors.initials: I
authors.lastname: Badenhausser
authors.affiliation: Institute of Ecology and Environmental Sciences-Paris (UPMC-CNRS-IRD-INRA-UPEC-Paris Diderot), Université Pierre et Marie Curie, UMR 7618, 7 quai St Bernard, 75005, Paris, France.
authors.forename: Nicolas
authors.initials: N
authors.lastname: Loeuille
authors.affiliation: DNPW, Agroecology, Georg-August University, Göttingen, Germany.|Institute of Landscape Ecology, University of Münster, Münster, Germany.
authors.forename: Christoph
authors.initials: C
authors.lastname: Scherber
authors.affiliation: UMR7372, Centre d'Etudes Biologiques de Chizé, CNRS-Université de La Rochelle, Villiers en Bois, 79360, Beauvoir sur Niort, France.|USC1339, Centre d'Etudes Biologiques de Chizé, INRA, Villiers en Bois, 79360, Beauvoir sur Niort, France.|LTER, ZA Plaine & Val de Sèvre, CNRS, 79360, Villiers en Bois, France.
authors.forename: Nicolas
authors.initials: N
authors.lastname: Gross
mesh_terms: D000818:Animals; D044822:Biodiversity; D018533:Biomass; D020387:Food Chain; D005602:France; D060434:Herbivory; D009987:Orthoptera / Q000502:physiology*; D018521:Plant Physiological Phenomena; D012621:Seasons
keywords: Biodiversity experiment; body size; complementarity effect; functional trait diversity; grassland; herbivore; incisor strength; insect communities; plant-herbivore interactions; trophic interactions