title: Herbivory makes major contributions to ecosystem carbon and nutrient cycling in tropical forests.
abstract: The functional role of herbivores in tropical rainforests remains poorly understood. We quantified the magnitude of, and underlying controls on, carbon, nitrogen and phosphorus cycled by invertebrate herbivory along a 2800 m elevational gradient in the tropical Andes spanning 12°C mean annual temperature. We find, firstly, that leaf area loss is greater at warmer sites with lower foliar phosphorus, and secondly, that the estimated herbivore-mediated flux of foliar nitrogen and phosphorus from plants to soil via leaf area loss is similar to, or greater than, other major sources of these nutrients in tropical forests. Finally, we estimate that herbivores consume a significant portion of plant carbon, potentially causing major shifts in the pattern of plant and soil carbon cycling. We conclude that future shifts in herbivore abundance and activity as a result of environmental change could have major impacts on soil fertility and ecosystem carbon sequestration in tropical forests.
authors.affiliation: Department of Forest Ecology and Management, Swedish University of Agricultural Sciences, Skogsmarksgränd, Umeå, SE-901 83, Sweden.
authors.forename: Daniel B
authors.initials: DB
authors.lastname: Metcalfe
authors.forename: Gregory P
authors.initials: GP
authors.lastname: Asner
authors.forename: Roberta E
authors.initials: RE
authors.lastname: Martin
authors.forename: Javier E
authors.initials: JE
authors.lastname: Silva Espejo
authors.forename: Walter Huaraca
authors.initials: WH
authors.lastname: Huasco
authors.forename: Felix F
authors.initials: FF
authors.lastname: Farfán Amézquita
authors.forename: Loreli
authors.initials: L
authors.lastname: Carranza-Jimenez
authors.forename: Darcy F
authors.initials: DF
authors.lastname: Galiano Cabrera
authors.forename: Liliana Durand
authors.initials: LD
authors.lastname: Baca
authors.forename: Felipe
authors.initials: F
authors.lastname: Sinca
authors.forename: Lidia P
authors.initials: LP
authors.lastname: Huaraca Quispe
authors.forename: Ivonne Alzamora
authors.initials: IA
authors.lastname: Taype
authors.forename: Luzmila Eguiluz
authors.initials: LE
authors.lastname: Mora
authors.forename: Angela Rozas
authors.initials: AR
authors.lastname: Dávila
authors.forename: Marlene Mamani
authors.initials: MM
authors.lastname: Solórzano
authors.forename: Beisit L
authors.initials: BL
authors.lastname: Puma Vilca
authors.forename: Judith M
authors.initials: JM
authors.lastname: Laupa Román
authors.forename: Patricia C
authors.initials: PC
authors.lastname: Guerra Bustios
authors.forename: Norma Salinas
authors.initials: NS
authors.lastname: Revilla
authors.forename: Raul
authors.initials: R
authors.lastname: Tupayachi
authors.forename: Cécile A J
authors.initials: CA
authors.lastname: Girardin
authors.forename: Christopher E
authors.initials: CE
authors.lastname: Doughty
authors.forename: Yadvinder
authors.initials: Y
authors.lastname: Malhi
mesh_terms: D000818:Animals; D057486:Carbon Cycle / Q000502:physiology*; D017753:Ecosystem; D005502:Food; D060434:Herbivory / Q000502:physiology*; D008954:Models, Biological; D010568:Peru; D018515:Plant Leaves / Q000737:chemistry*; D013057:Spectrum Analysis; D014197:Trees; D014329:Tropical Climate
keywords: Climate change; ecosystem biogeochemistry; montane rainforest; net primary productivity; nitrogen cycle; plant-soil feedbacks; soil phosphorus