title: Scaling leaf respiration with nitrogen and phosphorus in tropical forests across two continents.
abstract: Leaf dark respiration (Rdark) represents an important component controlling the carbon balance in tropical forests. Here, we test how nitrogen (N) and phosphorus (P) affect Rdarkand its relationship with photosynthesis using three widely separated tropical forests which differ in soil fertility. Rdarkwas measured on 431 rainforest canopy trees, from 182 species, in French Guiana, Peru and Australia. The variation in Rdarkwas examined in relation to leaf N and P content, leaf structure and maximum photosynthetic rates at ambient and saturating atmospheric CO2concentration. We found that the site with the lowest fertility (French Guiana) exhibited greater rates of Rdarkper unit leaf N, P and photosynthesis. The data from Australia, for which there were no phylogenetic overlaps with the samples from the South American sites, yielded the most distinct relationships of Rdarkwith the measured leaf traits. Our data indicate that no single universal scaling relationship accounts for variation in Rdarkacross this large biogeographical space. Variability between sites in the absolute rates of Rdarkand the Rdark: photosynthesis ratio were driven by variations in N- and P-use efficiency, which were related to both taxonomic and environmental variability.
authors.affiliation: School of Geosciences, University of Edinburgh, Edinburgh, EH9 3JN, UK.|Geography, College of Life and Environmental Sciences, University of Exeter, Amory Building, Exeter, EX4 4RJ, UK.
authors.forename: Lucy
authors.initials: L
authors.lastname: Rowland
authors.affiliation: School of Geosciences, University of Edinburgh, Edinburgh, EH9 3JN, UK.|Geography, College of Life and Environmental Sciences, University of Exeter, Amory Building, Exeter, EX4 4RJ, UK.
authors.forename: Joana
authors.initials: J
authors.lastname: Zaragoza-Castells
authors.affiliation: Division of Plant Sciences, Research School of Biology, Australian National University, Canberra, 2601, ACT, Australia.
authors.forename: Keith J
authors.initials: KJ
authors.lastname: Bloomfield
authors.affiliation: Centre for Integrative Ecology, School of Biological Sciences, University of Canterbury, Private Bag, 4800, Christchurch, New Zealand.
authors.forename: Matthew H
authors.initials: MH
authors.lastname: Turnbull
authors.affiliation: INRA, UMR 1137 Ecologie et Ecophysiologie Forestieres, Champenoux, 54280, France.
authors.forename: Damien
authors.initials: D
authors.lastname: Bonal
authors.affiliation: INRA UMR-ECOFOG, Campus agronomique - BP 316, 97379, Kourou, French Guiana, France.
authors.forename: Benoit
authors.initials: B
authors.lastname: Burban
authors.affiliation: Environmental Change Institute, School of Geography and the Environment, University of Oxford, South Parks Road, Oxford, OX1 3QY, UK.
authors.forename: Norma
authors.initials: N
authors.lastname: Salinas
authors.affiliation: Pontificia Universidad Catolica del Peru, Seccion Quimica, Av Universitaria 1801, San Miguel, Lima, Peru.
authors.forename: Eric
authors.initials: E
authors.lastname: Cosio
authors.affiliation: CSIRO, Land and Water, Tropical Forest Research Centre, Atherton, QLD, 4883, Australia.
authors.forename: Daniel J
authors.initials: DJ
authors.lastname: Metcalfe
authors.affiliation: CSIRO, Land and Water, Tropical Forest Research Centre, Atherton, QLD, 4883, Australia.
authors.forename: Andrew
authors.initials: A
authors.lastname: Ford
authors.affiliation: School of Geography, University of Leeds, Leeds, LS6 2AB, UK.
authors.forename: Oliver L
authors.initials: OL
authors.lastname: Phillips
authors.affiliation: Division of Plant Sciences, Research School of Biology, Australian National University, Canberra, 2601, ACT, Australia.|ARC Centre of Excellence in Plant Energy Biology, Division of Plant Sciences, Research School of Biology, Australian National University, Canberra, 2601, ACT, Australia.
authors.forename: Owen K
authors.initials: OK
authors.lastname: Atkin
authors.affiliation: Geography, College of Life and Environmental Sciences, University of Exeter, Amory Building, Exeter, EX4 4RJ, UK.|Division of Plant Sciences, Research School of Biology, Australian National University, Canberra, 2601, ACT, Australia.
authors.forename: Patrick
authors.initials: P
authors.lastname: Meir
mesh_terms: D001315:Australia; D019069:Cell Respiration; D003624:Darkness; D065928:Forests; D005616:French Guiana; D008027:Light; D009584:Nitrogen / Q000378:metabolism*; D010568:Peru; D010758:Phosphorus / Q000378:metabolism*; D010788:Photosynthesis; D018515:Plant Leaves / Q000033:anatomy & histology / Q000737:chemistry; D012044:Regression Analysis; D012987:Soil / Q000737:chemistry; D014329:Tropical Climate
chemical_list: D012987:Soil; D010758:Phosphorus; D009584:Nitrogen
keywords: leaf respiration; nitrogen (N); phosphorus (P); photosynthesis; tropical forest