Functional composition of the Amazonian tree flora and forests
Hans ter Steege, Lourens Poorter, Jesús Aguirre‐Gutiérrez, Claire Fortunel, William E. Magnusson, Oliver L. Phillips, Edwin Pos, Bruno Garcia Luize, Christopher Baraloto, Juan Ernesto Guevara, María‐José Endara, Timothy R. Baker, María Natalia Umaña, Masha T. van der Sande, Maihyra Marina Pombo, Matt S. McGlone, Frederick C. Draper, Iêda Leão do Amaral, Luiz de Souza Coêlho, Florian Wittmann, Francisca Dionízia de Almeida Matos, Diógenes de Andrade Lima Filho, Rafael P. Salomão, Carolina V. Castilho, Marcelo de Jesus Veiga Carim, María Teresa Fernández Piedade, Daniel Sabatier, Jean‐François Molino, Layon Oreste Demarchi, Juan David Cardenas Revilla, Jochen Schöngart, Mariana Victória Irume, Maria Pires Martins, José Renan da Silva Guimarães, José Ferreira Ramos, Olaf Bánki, Adriano Costa Quaresma, Nigel C. A. Pitman, Carlos A. Peres, Domingos de Jesus Rodrigues, Joseph E. Hawes, Everton José Almeida, Luciane Ferreira Barbosa, Larissa Cavalheiro, Márcia Cléia Vilela dos Santos, Evlyn Márcia Leão de Moraes Novo, Percy Núñez Vargas, Thiago Sanna Freire Silva, Eduardo Martins Venticinque, Ângelo Gilberto Manzatto, Neidiane Farias Costa Reis, John Terborgh, Katia Regina Casula, Eurídice N. Honorio Coronado, Abel Monteagudo Mendoza, Juan Carlos Montero, Cíntia Rodrigues de Souza, M. V. N. d'. Oliveira, Flávia R. C. Costa, Julien Engel, Ted R. Feldpausch, Nicolás Castaño Arboleda, Flávia Machado Durgante, Charles Eugene Zartman, Timothy J. Killeen, Beatriz Schwantes Marimon, Ben Hur Marimon, Rodolfo Vásquez, Bonifacio Mostacedo, Rafael L. Assis, Dário Dantas do Amaral, Hernán Castellanos, John Ethan Householder, Marcelo Brilhante de Medeiros, Marcelo Fragomeni Simon, Ana Andrade, José Luís Camargo, Susan G. W. Laurance, William F. Laurance, Lorena Maniguaje Rincón, Gisele Biem Mori, Juliana Schietti, Thaiane R. Sousa, Emanuelle de Sousa Farias, Maria Aparecida Lopes, José Leonardo Lima Magalhães, Henrique Eduardo Mendonça Nascimento, Helder Lima de Queiroz, Caroline da Cruz Vasconcelos, Gerardo A. Aymard C., Roel Brienen, Pâmella Leite de Sousa Assis, Darlene Gris, Karoline Aparecida Félix Ribeiro, Pablo R. Stevenson, Alejandro Araujo‐Murakami, Bruno Barçante Ladvocat Cintra, Yuri Oliveira Feitosa, Hugo F. Mogollón, Miles R. Silman
Abstract
Plants cope with the environment by displaying large phenotypic variation. Two spectra of global plant form and function have been identified: a size spectrum from small to tall species with increasing stem tissue density, leaf size, and seed mass; a leaf economics spectrum reflecting slow to fast returns on investments in leaf nutrients and carbon. When species assemble to communities it is assumed that these spectra are filtered by the environment to produce community level functional composition. It is unknown what are the main drivers for community functional composition in a large area such as Amazonia. We use 13 functional traits, including wood density, seed mass, leaf characteristics, breeding system, nectar production, fruit type, and root characteristics of 812 tree genera (5211 species), and find that they describe two main axes found at the global scale. At community level, the first axis captures not only the ‘fast-slow spectrum’, but also most size-related traits. Climate and disturbance explain a minor part of this variance compared to soil fertility. Forests on poor soils differ largely in terms of trait values from those on rich soils. Trait composition and soil fertility exert a strong influence on forest functioning: biomass and relative biomass production. Using 13 functional traits we characterize the Amazonian trees and the communities they form. Amazonian tree communities are distributed along a fast-slow-spectrum. This results in clear differences in traits among these forests, as well as their biomass and biomass productivity.