title: Producer nutritional quality controls ecosystem trophic structure.
abstract: Trophic structure, or the distribution of biomass among producers and consumers, determines key ecosystem values, such as the abundance of infectious, harvestable or conservation target species, and the storage and cycling of carbon and nutrients. There has been much debate on what controls ecosystem trophic structure, yet the answer is still elusive. Here we show that the nutritional quality of primary producers controls the trophic structure of ecosystems. By increasing the efficiency of trophic transfer, higher producer nutritional quality results in steeper ecosystem trophic structure, and those changes are more pronounced in terrestrial than in aquatic ecosystems probably due to the more stringent nutritional limitation of terrestrial herbivores. These results explain why ecosystems composed of highly nutritional primary producers feature high consumer productivity, fast energy recycling, and reduced carbon accumulation. Anthropogenic changes in producer nutritional quality, via changes in trophic structure, may alter the values and functions of ecosystems, and those alterations may be more important in terrestrial ecosystems.
authors.affiliation: Dauphin Island Sea Lab and Department of Marine Sciences, University of South Alabama, Dauphin Island, Alabama, United States of America. jcebrian@disl.org
authors.forename: Just
authors.initials: J
authors.lastname: Cebrian
authors.forename: Jonathan B
authors.initials: JB
authors.lastname: Shurin
authors.forename: Elizabeth T
authors.initials: ET
authors.lastname: Borer
authors.forename: Bradley J
authors.initials: BJ
authors.lastname: Cardinale
authors.forename: Jacqueline T
authors.initials: JT
authors.lastname: Ngai
authors.forename: Melinda D
authors.initials: MD
authors.lastname: Smith
authors.forename: William F
authors.initials: WF
authors.lastname: Fagan
mesh_terms: D000818:Animals; D018533:Biomass; D003247:Conservation of Natural Resources; D017753:Ecosystem; D004734:Energy Metabolism; D005502:Food; D006801:Humans