title: Variation in leaf wettability traits along a tropical montane elevation gradient.
abstract: Leaf wetting is often considered to have negative effects on plant function, such that wet environments may select for leaves with certain leaf surface, morphological, and architectural traits that reduce leaf wettability. However, there is growing recognition that leaf wetting can have positive effects. We measured variation in two traits, leaf drip tips and leaf water repellency, in a series of nine tropical forest communities occurring along a 3300-m elevation gradient in southern Peru. To extend this climatic gradient, we also assembled published leaf water repellency values from 17 additional sites. We then tested hypotheses for how these traits should vary as a function of climate. Contrary to expectations, we found that the proportion of species with drip tips did not increase with increasing precipitation. Instead, drip tips increased with increasing temperature. Moreover, leaf water repellency was very low in our sites and the global analysis indicated high repellency only in sites with low precipitation and temperatures. Our findings suggest that drip tips and repellency may not solely reflect the negative effects of wetting on plant function. Understanding the drivers of leaf wettability traits can provide insight into the effects of leaf wetting on plant, community, and ecosystem function.
authors.affiliation: Environmental Change Institute, School of Geography and the Environment, University of Oxford, Oxford, OX1 3QY, UK.|Ecosystem Fluxes Group, Laboratory for Atmospheric Chemistry, Paul Scherrer Institute, 5232 Villigen, Switzerland.
authors.forename: Gregory R
authors.initials: GR
authors.lastname: Goldsmith
authors.affiliation: Environmental Change Institute, School of Geography and the Environment, University of Oxford, Oxford, OX1 3QY, UK.
authors.forename: Lisa Patrick
authors.initials: LP
authors.lastname: Bentley
authors.affiliation: Environmental Change Institute, School of Geography and the Environment, University of Oxford, Oxford, OX1 3QY, UK.
authors.forename: Alexander
authors.identifier: http://orcid.org/0000-0003-2358-9367
authors.initials: A
authors.lastname: Shenkin
authors.affiliation: Environmental Change Institute, School of Geography and the Environment, University of Oxford, Oxford, OX1 3QY, UK.|Universidad Nacional San Antonio Abad del Cusco, Avenida de la Cultura, Nro. 733, Cusco, Peru.
authors.forename: Norma
authors.initials: N
authors.lastname: Salinas
authors.affiliation: Environmental Change Institute, School of Geography and the Environment, University of Oxford, Oxford, OX1 3QY, UK.
authors.forename: Benjamin
authors.initials: B
authors.lastname: Blonder
authors.affiliation: Department of Global Ecology, Carnegie Institution for Science, 260 Panama Street, Stanford, CA 94305, USA.
authors.forename: Roberta E
authors.initials: RE
authors.lastname: Martin
authors.affiliation: Universidad Nacional San Antonio Abad del Cusco, Avenida de la Cultura, Nro. 733, Cusco, Peru.
authors.forename: Rosa
authors.initials: R
authors.lastname: Castro-Ccossco
authors.affiliation: Universidad Nacional San Antonio Abad del Cusco, Avenida de la Cultura, Nro. 733, Cusco, Peru.
authors.forename: Percy
authors.initials: P
authors.lastname: Chambi-Porroa
authors.affiliation: Instituto Multidisciplinario de Biología Vegetal and FCEFyN, Universidad Nacional de Córdoba - CONICET, C.C. 495, 5000 Córdoba, Argentina.
authors.forename: Sandra
authors.initials: S
authors.lastname: Diaz
authors.affiliation: Department of Ecology and Evolutionary Biology, University of Arizona, Tucson, AZ 85721, USA.
authors.forename: Brian J
authors.initials: BJ
authors.lastname: Enquist
authors.affiliation: Department of Global Ecology, Carnegie Institution for Science, 260 Panama Street, Stanford, CA 94305, USA.
authors.forename: Gregory P
authors.initials: GP
authors.lastname: Asner
authors.affiliation: Environmental Change Institute, School of Geography and the Environment, University of Oxford, Oxford, OX1 3QY, UK.
authors.forename: Yadvinder
authors.initials: Y
authors.lastname: Malhi
mesh_terms: D000531:Altitude; D017753:Ecosystem; D010802:Phylogeny; D018515:Plant Leaves / Q000033:anatomy & histology / Q000502:physiology*; D019655:Quantitative Trait, Heritable; D011891:Rain; D013045:Species Specificity; D013696:Temperature; D014329:Tropical Climate; D014867:Water; D017155:Wettability
chemical_list: D014867:Water
keywords: cloud forest; contact angle; drip tips; ecohydrology; foliar water uptake; functional traits; leaf hydrophobicity; leaf water repellency