Variation in stem mortality rates determines patterns of above‐ground biomass in A mazonian forests: implications for dynamic global vegetation models
Year: 2016
Type: article
Abstract: Understanding the processes that determine above-ground biomass (AGB) in Amazonian forests is important for predicting the sensitivity of these ecosystems to environmental change and for designing and evaluating dynamic global vegetation models (DGVMs). AGB is determined by inputs from woody productivity [woody net primary productivity (NPP)] and the rate at which carbon is lost through tree mortality. Here, we test whether two direct metrics of tree mortality (the absolute rate of woody biomass loss and the rate of stem mortality) and/or woody NPP, control variation in AGB among 167 plots in intact forest across Amazonia. We then compare these relationships and the observed variation in AGB and woody NPP with the predictions of four DGVMs. The observations show that stem mortality rates, rather than absolute rates of woody biomass loss, are the most important predictor of AGB, which is consistent with the importance of stand size structure for determining spatial variation in AGB. The relationship between stem mortality rates and AGB varies among different regions of Amazonia, indicating that variation in wood density and height/diameter relationships also influences AGB. In contrast to previous findings, we find that woody NPP is not correlated with stem mortality rates and is weakly positively correlated with AGB. Across the four models, basin-wide average AGB is similar to the mean of the observations. However, the models consistently overestimate woody NPP and poorly represent the spatial patterns of both AGB and woody NPP estimated using plot data. In marked contrast to the observations, DGVMs typically show strong positive relationships between woody NPP and AGB. Resolving these differences will require incorporating forest size structure, mechanistic models of stem mortality and variation in functional composition in DGVMs.
Source: Global Change Biology
DOI: 10.1111/gcb.13315
Authors: Michelle O. Johnson, David Galbraith, Manuel Gloor, Hannes De Deurwaerder, Matthieu Guimberteau, Anja Rammig, Kirsten Thonicke, Hans Verbeeck, Celso von Randow, Abel Monteagudo, Oliver L. Phillips, Roel J. W. Brienen, Ted R. Feldpausch, Gabriela Lopez Gonzalez, Sophie Fauset, Carlos A. Quesada, Bradley Christoffersen, Philippe Ciais, Gilvan Sampaio, Bart Kruijt, Patrick Meir, Paul Moorcroft, Ke Zhang, Esteban Alvarez‐Davila, Atila Alves de Oliveira, Ieda Amaral, Ana Andrade, Luiz E. O. C. Aragao, Alejandro Araujo‐Murakami, Eric J. M. M. Arets, Luzmila Arroyo, Gerardo A. Aymard, Christopher Baraloto, Jocely Barroso, Damien Bonal, Rene Boot, Jose Camargo, Jerome Chave, Alvaro Cogollo, Fernando Cornejo Valverde, Antonio C. Lola da Costa, Anthony Di Fiore, Leandro Ferreira, Niro Higuchi, Euridice N. Honorio, Tim J. Killeen, Susan G. Laurance, William F. Laurance, Juan Licona, Thomas Lovejoy, Yadvinder Malhi, Bia Marimon, Ben Hur Marimon, Darley C. L. Matos, Casimiro Mendoza, David A. Neill, Guido Pardo, Marielos Peña‐Claros, Nigel C. A. Pitman, Lourens Poorter, Adriana Prieto, Hirma Ramirez‐Angulo, Anand Roopsind, Agustin Rudas, Rafael P. Salomao, Marcos Silveira, Juliana Stropp, Hans ter Steege, John Terborgh, Raquel Thomas, Marisol Toledo, Armando Torres‐Lezama, Geertje M. F. van der Heijden, Rodolfo Vasquez, Ima Cèlia Guimarães Vieira, Emilio Vilanova, Vincent A. Vos, Timothy R. Baker
Institutions: University of Leeds, Ghent University, Centre National de la Recherche Scientifique, École Pratique des Hautes Études, Université de Versailles Saint-Quentin-en-Yvelines, Commissariat à l'Énergie Atomique et aux Énergies Alternatives, Université Paris-Saclay, Sorbonne Université, Milieux environnementaux, transferts et interactions dans les hydrosystèmes et les sols, Laboratoire des Sciences du Climat et de l'Environnement, Université Pierre-et-Marie-Curie, Potsdam Institute for Climate Impact Research, Technical University of Munich, Instituto Nacional de Pesquisas Espaciais, Jardín Botánico de Missouri, University of Exeter, Instituto Nacional de Pesquisas da Amazônia, Los Alamos National Laboratory, University of Edinburgh, Wageningen University & Research, Australian National University, Harvard University, Cooperative Institute for Mesoscale Meteorological Studies, University of Oklahoma, Fundación Con Vida, Gabriel René Moreno Autonomous University, Museo de Historia Natural Noel Kempff Mercado, Universidad Nacional Experimental de los Llanos Occidentales Ezequiel Zamora, Florida International University, Universidade Federal do Acre, Ecologie et Ecophysiologie Forestières, Institut National de la Recherche Agronomique, Tropenbos International, Université Toulouse III - Paul Sabatier, Evolution et Diversité Biologique, Fundación Jardín Botánico “Joaquín Antonio Uribe” de Medellín, Amazon National University of Madre de Dios, Universidade Federal do Pará, The University of Texas at Austin, Museu Paraense Emílio Goeldi, Instituto de Investigaciones de la Amazonía Peruana, World Wildlife Fund, James Cook University, Bolivian Forest Research Institute, George Mason University, University of Oxford, Universidade do Estado de Mato Grosso, Universidad Estatal Amazónica, Universidad Autónoma del Beni, Duke University, Universidad Nacional de Colombia, Universidad de Los Andes, Iwokrama International Centre for Rainforest Conservation and Development, Universidade Federal de Alagoas, Naturalis Biodiversity Center, University of Nottingham
Language: English
Subfield: Forestry
Domain: Life Sciences
SDGs: Life on land, Climate action
Open Access status: hybrid
Estimated APC paid: $4,550
Funders: Smithsonian Institution, U.S. Department of Energy, Gordon and Betty Moore Foundation, Wildlife Conservation Society, Leverhulme Trust, European Commission, Conselho Nacional de Desenvolvimento Científico e Tecnológico, Natural Environment Research Council, European Research Council, Seventh Framework Programme, Division of Arctic Sciences, Los Alamos National Laboratory
Awards: Raising the alert about critical feedbacks between climate and long-term land use change in the Amazon, G2177296236, Role Of Biodiversity In climate change mitigatioN, G2325242462, G2605972103, G2622176538, Assessing the Impacts of the Recent Amazonian Drought, Amazon Integrated Carbon Analysis / AMAZONICA, G3089010852, G3343988683, G3789916812, Tropical Biomes in Transition, G511633942, Assessing the Impacts of the Recent Amazonian Drought, Niche evolution of South American trees and its consequences, G5833630370, Amazon Integrated Carbon Analysis / AMAZONICA, G7166077787, G7188122809, Understanding how drought affects the risk of increased mortality in tropical rain forests, Do past fires explain current carbon dynamics of Amazonian forests?, Operational Global Carbon Observing System, BIOmes of Brasil - Resilience, rEcovery, and Diversity: BIO-RED, TREMOR: Mechanisms and consequences of increasing TREe MORtality in Amazonian rainforests, G8616239171, G958672671
OpenAlex ID: W2340539073