Search

Your search keyword '"Georges Chuyong"' showing total 6 results
Start Over Author "Georges Chuyong"
6 results on '"Georges Chuyong"'

1. Pan-tropical prediction of forest structure from the largest trees

Author

Narayanaswamy Parthasarathy, Stephen P. Hubbell, Cintia Rodrigues de Souza, Takeshi Toma, Ben Swanepoel, Raphaël Pélissier, Donatien Zebaze, Luzmila Arroyo, Juliana Stropp, James R. Kellner, Alejandro Araujo-Murakami, Thomas E. Lovejoy, Benoît Cassart, Ben Hur Marimon Junior, James Grogan, Sebastian K. Herzog, Yadvinder Malhi, Krisna Gajapersad, José Luís Camargo, Christelle Gonmadje, Renato Valencia, Connie J. Clark, Denise Sasaki, Fabien Wagner, Francesco Rovero, Katrin Boehning-Gaese, David Kenfack, Olaf Bánki, John Terborgh, Ferry Slik, Arafat S. Mtui, Javier Silva Espejo, Hans Beeckman, Germaine Alexander Parada Gutierrez, Tinde van Andel, Luis Valenzuela, Thalès de Haulleville, Hans ter Steege, Elizabeth Kearsley, Martin J. P. Sullivan, Wilson Roberto Spironello, Rodolfo Vasque, Emmanuel H. Martin, Thomas Duncan, William F. Laurance, Jason Vleminckx, Paulus Matius, Charles De Cannière, Yves Laumonier, Ted R. Feldpausch, Andrew R. Marshall, John R. Poulsen, J. Daniel Soto, Priya Davidar, Jean François Gillet, Iêda Leão do Amaral, Papi Puspa Warsudi, Eurídice N. Honorio Coronado, Vincent A. Vos, Laurent Descroix, Nicolas Texier, Philippe Saner, Roderick Zagt, Marc P. E. Parren, Luiz Marcelo Brum Rossi, Robert Bitariho, Fernando Cornejo Valverde, Jon Lloyd, Nina Farwig, James Singh, Jean-Louis Doucet, Francis Q. Brearley, Leandro Valle Ferreira, Celso Paulo de Azevedo, Ervan Rutishauser, Johanna Hurtado, Bruno Hérault, Albert Angbonga-Basia, Jérôme Chave, David A. Neill, Jean Claude Razafimahaimodison, Pierre Ploton, Hilandia Brandão, Susan G. Laurance, Richard Condit, Roel J. W. Brienen, Jean-François Bastin, Ana Andrade, Marcos Silveira, Oliver L. Phillips, Gauthier Ligot, David B. Clark, Casimero Mendoza Bautista, Narayanan Ayyappan, Robin L. Chazdon, Hans Verbeeck, Santiago Espinosa, Jürgen Homeier, Mireille Breuer-Ndoundou Hockemba, Simon L. Lewis, Patricia Alvarez-Loyayza, Vincent Droissart, Sassan Saatchi, Nigel C. A. Pitman, Victoria Meyer, Nicolas Barbier, Wannes Hubau, Jorcely Barroso, Nicolas Labrière, Plinio Sist, Georges Chuyong, Pascal Boeckx, Hugo Romero Saltos, Antonio Ferraz, David Harris, Verginia Wortel, Pandi Vivek, Mark Schulze, Bonaventure Sonké, Jan Bogaert, Abel Monteagudo-Mendoza, Guido Pardo, Quentin Ponette, Ahimsa Campos-Arceiz, Michael Kessler, Beatriz Schwantes Marimon, Samir Gonçalves Rolim, Maxime Réjou-Méchain, Koen Hufkens, Narcisse Guy Kamdem, Adeline Fayolle, Aurélie Dourdain, Christine Fletcher, Moses Libalah, B.R. Ramesh, Research Unit of Landscape Ecology and Plant Production Systems, Université libre de Bruxelles (ULB), Carbon For Expert, California Institute of Technology (CALTECH), Botanique et Modélisation de l'Architecture des Plantes et des Végétations (UMR AMAP), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [France-Sud]), Ecologie des forêts de Guyane (UMR ECOFOG), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-AgroParisTech-Université de Guyane (UG)-Centre National de la Recherche Scientifique (CNRS)-Université des Antilles (UA), Département Environnements et Sociétés (Cirad-ES), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad), Université de Liège, University of Mary Washington, Instituto Nacional de Pesquisas da Amazônia (INPA), Universidad Autonoma Gabriel René Moreno (UAGRM), Institut Français de Pondichéry (IFP), Ministère de l'Europe et des Affaires étrangères (MEAE)-Centre National de la Recherche Scientifique (CNRS), Institute for Biodiversity and Ecosystem Dynamics (IBED), University of Amsterdam [Amsterdam] (UvA), Universidade Federal do Acre (UFAC), School of Engineering and Science, Jacobs University [Bremen], Laboratory of Applied Physical Chemistry, Universiteit Gent = Ghent University (UGENT), School of Geography [Leeds], University of Leeds, Universidad Nacional de San Antonio Abad del Cusco (UNSAAC), Evolution et Diversité Biologique (EDB), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS), University of Buea, Department of Computer Science, King‘s College London, Patrimoines Locaux et Gouvernance (PALOC), Muséum national d'Histoire naturelle (MNHN)-Institut de Recherche pour le Développement (IRD), Gembloux Agro-Bio Tech [Gembloux], Department of Ecology-Conservation Ecology, Faculty of Biology, Philipps Universität Marburg = Philipps University of Marburg, AgroBioTech, Forest Research Institute Malaysia (FRIM), Mount Holyoke College, Royal Botanic Gardens, Georg-August-University = Georg-August-Universität Göttingen, Royal Museum for Central Africa [Tervuren] (RMCA), Smithsonian Conservation Biology Institute, Center for Conservation Education and Sustainability, MRC 705, Box 37012, Washington, DC, VA 20013-7012, USA, Universität Zürich [Zürich] = University of Zurich (UZH), AgroParisTech, Center for International Forestry Research (CIFOR), Consultative Group on International Agricultural Research [CGIAR] (CGIAR), Université de Yaoundé I, Imperial College London, Environmental Science and Policy Department and the Department of Public and International Affairs, George Mason University [Fairfax], Environmental Change Inst., School of Geography and the Environment, University of Oxford, Universidade do Estado de Mato Grosso (UNEMAT), Centre Maurice Halbwachs (CMH), École des hautes études en sciences sociales (EHESS)-Centre National de la Recherche Scientifique (CNRS)-Département de Sciences sociales ENS-PSL, École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL), Missouri Botanical Garden, Universidad Estatal Amazonica, Universidad Autonoma del Beni, Analytical and Biophysical Environmental Chemistry (CABE), University of Geneva, Sciences II, Division of Marine Science and Conservation, Nicholas School of the Environment, Duke University [Durham], Université Catholique de Louvain = Catholic University of Louvain (UCL), Département Systèmes Biologiques (Cirad-BIOS), MUSE – Science Museum of Trento, Forêts et Sociétés (UPR Forêts et Sociétés), Amazonia Central, Brazilian Agricultural Research Corporation (Embrapa), JRC Institute for Environment and Sustainability (IES), European Commission - Joint Research Centre [Ispra] (JRC), Department of Forest Vegetation, Forestry and Forest Products Research Institute (FFPRI), Laboratorio de Ecología de Plantas y Herbario QCA, Escuela de Ciencias Biológicas, Pontificia Universidad Católica del Ecuador, Chercheur indépendant, Computational & Applied Vegetation Ecology (CAVElab), Instituto Nacional de Pesquisas Espaciais (INPE), Ministério da Ciência, Tecnologia e Inovação, Biodiversity Department, Center for Agricultural Research in Suriname (CELOS), Laboratoire de Botanique systématique et d'Ecologie [ENS Yaoudé], Université de Yaoundé I-École normale supérieure [ENS] - Yaoundé 1, Université Libre de Bruxelles [Bruxelles] (ULB), Université des Antilles (UA)-Université de Guyane (UG)-Centre National de la Recherche Scientifique (CNRS)-AgroParisTech-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA), Centre National de la Recherche Scientifique (CNRS)-Ministère de l'Europe et des Affaires étrangères (MEAE), Ghent University [Belgium] (UGENT), Universidad Nacional San Antonio Abad del Cusco, Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), Phillips Universität (Marburg), Georg-August-Universität Göttingen, University of Zurich, Université de Yaoundé, École normale supérieure - Paris (ENS Paris)-École des hautes études en sciences sociales (EHESS)-Centre National de la Recherche Scientifique (CNRS), Missouri Botanical Garden (USA), Université Catholique de Louvain (UCL), Pontificia Universidad Catolica del Ecuador, Université de Yaoundé I [Yaoundé]-École normale supérieure [ENS] - Yaoundé 1, Systems Ecology, Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Institut National de la Recherche Agronomique (INRA)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut de Recherche pour le Développement (IRD [France-Sud]), Universiteit Gent = Ghent University [Belgium] (UGENT), Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées, Georg-August-University [Göttingen], University of Oxford [Oxford], École normale supérieure - Paris (ENS Paris), and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École des hautes études en sciences sociales (EHESS)-Centre National de la Recherche Scientifique (CNRS)

Subjects
P33 - Chimie et physique du sol, 0106 biological sciences, pan-tropical, 010504 meteorology & atmospheric sciences, P40 - Météorologie et climatologie, REDD, Rainforest, F50 - Anatomie et morphologie des plantes, 010603 evolutionary biology, 01 natural sciences, Basal area, [SDV.SA.SF]Life Sciences [q-bio]/Agricultural sciences/Silviculture, forestry, K01 - Foresterie - Considérations générales, Quadratic mean diameter, Ecology, Evolution, Behavior and Systematics, ComputingMilieux_MISCELLANEOUS, 0105 earth and related environmental sciences, Changement climatique, Global and Planetary Change, Biomass (ecology), Tree canopy, Ecology, carbon, Diameter at breast height, large trees, Tropics, 15. Life on land, Structure du peuplement, séquestration du carbone, climate change, 13. Climate action, Forêt, Environmental science, Physical geography, tropical forest ecology, REDD+, Woody plant, forest structure
Abstract

© 2018 John Wiley & Sons Ltd Aim: Large tropical trees form the interface between ground and airborne observations, offering a unique opportunity to capture forest properties remotely and to investigate their variations on broad scales. However, despite rapid development of metrics to characterize the forest canopy from remotely sensed data, a gap remains between aerial and field inventories. To close this gap, we propose a new pan-tropical model to predict plot-level forest structure properties and biomass from only the largest trees. Location: Pan-tropical. Time period: Early 21st century. Major taxa studied: Woody plants. Methods: Using a dataset of 867 plots distributed among 118 sites across the tropics, we tested the prediction of the quadratic mean diameter, basal area, Lorey's height, community wood density and aboveground biomass (AGB) from the ith largest trees. Results: Measuring the largest trees in tropical forests enables unbiased predictions of plot- and site-level forest structure. The 20 largest trees per hectare predicted quadratic mean diameter, basal area, Lorey's height, community wood density and AGB with 12, 16, 4, 4 and 17.7% of relative error, respectively. Most of the remaining error in biomass prediction is driven by differences in the proportion of total biomass held in medium-sized trees (50–70 cm diameter at breast height), which shows some continental dependency, with American tropical forests presenting the highest proportion of total biomass in these intermediate-diameter classes relative to other continents. Main conclusions: Our approach provides new information on tropical forest structure and can be used to generate accurate field estimates of tropical forest carbon stocks to support the calibration and validation of current and forthcoming space missions. It will reduce the cost of field inventories and contribute to scientific understanding of tropical forest ecosystems and response to climate change.

Published
2018

2. Toward a general tropical forest biomass prediction model from very high resolution optical satellite images

Author

Christophe Proisy, Pierre Couteron, Cécile Antin, David Kenfack, S.T. Momo, Duncan W. Thomas, Gislain Ii Mofack, Nicolas Barbier, Maxime Réjou-Méchain, Jean-Philippe Gastellu-Etchegorry, Jean-François Bastin, N. Barathan, Narcisse Guy Kamdem, P. Petronelli, N. Balachandran, P. Verley, Uta Berger, Gilles Dauby, D. Zebaze Dongmo, Pierre Ploton, S. Pargal, Nicolas Texier, Raphaël Pélissier, Moses Libalah, Vincent Droissart, Georges Chuyong, Bonaventure Sonké, N. Ayyappan, Botanique et Modélisation de l'Architecture des Plantes et des Végétations (UMR AMAP), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [France-Sud]), AgroParisTech, Institut Français de Pondichéry (IFP), Ministère de l'Europe et des Affaires étrangères (MEAE)-Centre National de la Recherche Scientifique (CNRS), Research Unit of Landscape Ecology and Plant Production Systems, Université libre de Bruxelles (ULB), University of Buéa, Diversité, adaptation, développement des plantes (UMR DIADE), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [France-Sud]), Evolutionary Biology and Ecology [ULB], Herbarium et Bibliothèque de Botanique africain, Centre d'études spatiales de la biosphère (CESBIO), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Laboratoire de Botanique systématique et d'Ecologie [ENS Yaoudé], Université de Yaoundé I-École normale supérieure [ENS] - Yaoundé 1, Smithsonian Tropical Research Institute, Ecologie des forêts de Guyane (UMR ECOFOG), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-AgroParisTech-Université de Guyane (UG)-Centre National de la Recherche Scientifique (CNRS)-Université des Antilles (UA), Washington State University (WSU), Technische Universität Dresden = Dresden University of Technology (TU Dresden), ANR-12-EBID-0002, European Project: 266546,EC:FP7:ENV,FP7-ERANET-2010-RTD,BIODIVERSA2(2010), Institut des sciences et industries du vivant et de l'environnement (ISIVE), Centre National de la Recherche Scientifique (CNRS)-Ministère de l'Europe et des Affaires étrangères (MEAE), Université Libre de Bruxelles [Bruxelles] (ULB), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Observatoire Midi-Pyrénées (OMP), Université Fédérale Toulouse Midi-Pyrénées-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Université de Yaoundé I [Yaoundé]-École normale supérieure [ENS] - Yaoundé 1, Technische Universität Dresden (TUD), Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Institut National de la Recherche Agronomique (INRA)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut de Recherche pour le Développement (IRD [France-Sud]), Institut de Recherche pour le Développement (IRD [France-Sud])-Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad), Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), and Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)

Subjects
0106 biological sciences, Canopy, 010504 meteorology & atmospheric sciences, Tropical forests, forêt tropicale, Imagerie par satellite, Residual, [SDV.BID.SPT]Life Sciences [q-bio]/Biodiversity/Systematics, Phylogenetics and taxonomy, 01 natural sciences, Basal area, [SDV.SA.SF]Life Sciences [q-bio]/Agricultural sciences/Silviculture, forestry, Lacunarity, K01 - Foresterie - Considérations générales, Biomasse, Dynamique des populations, Satellite imagery, ComputingMilieux_MISCELLANEOUS, U10 - Informatique, mathématiques et statistiques, Inventaire forestier, Geology, Tropical forest biomass, Forêt, Fourier transform, Ordination, Passive optical imagery, Télédétection, REDD, Soil Science, Structural basin, 010603 evolutionary biology, Texture, Computers in Earth Sciences, Ressource forestière, 0105 earth and related environmental sciences, Remote sensing, model, Méthode statistique, Tropics, Modèle de simulation, 15. Life on land, Forest carbon, Environmental science, U30 - Méthodes de recherche, Canopy structure, satellite images
Abstract

International audience; Very high spatial resolution (VHSR) optical satellite imagery has shown good potential to provide non-saturating proxies of tropical forest aboveground biomass (AGB) from the analysis of canopy texture, for instance through the Fourier Transform Textural Ordination method. Empirical case studies however showed that the relationship between Fourier texture features and forest AGB varies across forest types and regions of the world, limiting model transferability. A better understanding of the biophysical mechanisms on which canopy texture – forest AGB relation relies is a prerequisite to move toward broad scale applications. Here we simulated VHSR optical canopy scenes in identical sun-sensor geometry for 279 1-ha tropical forest inventory plots distributed across the tropics. Our aim was to assess the respective merits and complementarity of two types of texture analysis techniques (i.e. Fourier and lacunarity) on a set of forests with contrasted structure and geographical origin, and develop a general texture-based approach for tropical forest AGB mapping. Across forests, Fourier texture captured a gradient of stands mean crown size reflecting well the progressive changes in stand structure throughout forest aggradation phase (e.g. Pearson's r=−0.42 with basal area) while lacunarity texture captured a gradient of canopy openness (, i.e. Pearson's r=−0.57 with stand gap fraction). Both types of texture indices were highly complementary for predicting forest AGB at the global level (so-called FL-model). The residual error of the FL-model was structured across sites and could be partially captured with a bioclimatic proxy, further improving the performance of the global model (so-called FLE-model) and reducing site-level biases. The FLE model was tested on a set of real Pleiades images covering a mosaic of high-biomass forests in the Congo basin (mean AGB over 49 field plots: 359±98Mgha−1), leading to a significant relationship (R2=0.47 on validation data) with reasonable error levels (

Published
2017

3. Closing a gap in tropical forest biomass estimation: accounting for crown mass variation in pantropical allometries

Author

Raphaël Pélissier, Donatien Zebaze, Maxime Réjou-Méchain, Adeline Fayolle, Vincent Droissart, Gilles Dauby, F. Boyemba Bosela, Vivien Rossi, Alfred Ngomanda, Matieu Henry, Moses Libalah, Nicolas Texier, Narcisse Guy Kamdem, Georges Chuyong, J. Katembo Mukirania, Nicolas Barbier, Uta Berger, Pierre Ploton, Duncan W. Thomas, Rosa C. Goodman, Bonaventure Sonké, David Kenfack, Pierre Couteron, and Stéphane Takoudjou Momo

Subjects
Estimation, Biomass (ecology), Crown (botany), Mass variation, Pantropical, Forestry, Biology, Tropical forest, Closing (morphology)
Abstract

Accurately monitoring tropical forest carbon stocks is an outstanding challenge. Allometric models that consider tree diameter, height and wood density as predictors are currently used in most tropical forest carbon studies. In particular, a pantropical biomass model has been widely used for approximately a decade, and its most recent version will certainly constitute a reference in the coming years. However, this reference model shows a systematic bias for the largest trees. Because large trees are key drivers of forest carbon stocks and dynamics, understanding the origin and the consequences of this bias is of utmost concern. In this study, we compiled a unique tree mass dataset on 673 trees measured in five tropical countries (101 trees > 100 cm in diameter) and an original dataset of 130 forest plots (1 ha) from central Africa to quantify the error of biomass allometric models at the individual and plot levels when explicitly accounting or not accounting for crown mass variations. We first showed that the proportion of crown to total tree aboveground biomass is highly variable among trees, ranging from 3 to 88 %. This proportion was constant on average for trees < 10 Mg (mean of 34 %) but, above this threshold, increased sharply with tree mass and exceeded 50 % on average for trees ≥ 45 Mg. This increase coincided with a progressive deviation between the pantropical biomass model estimations and actual tree mass. Accounting for a crown mass proxy in a newly developed model consistently removed the bias observed for large trees (> 1 Mg) and reduced the range of plot-level error from −23–16 to 0–10 %. The disproportionally higher allocation of large trees to crown mass may thus explain the bias observed recently in the reference pantropical model. This bias leads to far-from-negligible, but often overlooked, systematic errors at the plot level and may be easily corrected by accounting for a crown mass proxy for the largest trees in a stand, thus suggesting that the accuracy of forest carbon estimates can be significantly improved at a minimal cost.

Published
2015

4. Annual Rainfall and Seasonality Predict Pan-tropical Patterns of Liana Density and Basal Area

Author

Stefan A. Schnitzer, Guillermo Ibarra-Manríquez, Z.Q. Cai, Terese B. Hart, Georges Chuyong, Duncan W. Thomas, Miguel Martínez-Ramos, Marc P. E. Parren, Frans Bongers, Hugo Romero-Saltos, Kalan Ickes, Jean-Remy Makana, Corneille E. N. Ewango, Jérôme Chave, Saara J. DeWalt, Sainge Moses, David B. Clark, Diego R. Pérez-Salicrup, Joseph Mascaro, Helene C. Muller-Landau, Esteban Gortaire, Francis E. Putz, Jeffrey J. Gerwing, Manuel J. Macía, Narayanaswamy Parthasarathy, Robyn J. Burnham, and David Kenfack

Subjects
0106 biological sciences, Ecology, Species diversity, Tropics, 15. Life on land, Seasonality, Biology, medicine.disease, 010603 evolutionary biology, 01 natural sciences, Basal area, Liana, Abundance (ecology), Dry season, medicine, Precipitation, Physical geography, Ecology, Evolution, Behavior and Systematics, 010606 plant biology & botany
Abstract

We test the hypotheses proposed by Gentry and Schnitzer that liana density and basal area in tropical forests vary negatively with mean annual precipitation (MAP) and positively with seasonality. Previous studies correlating liana abundance with these climatic variables have produced conflicting results, warranting a new analysis of drivers of liana abundance based on a different dataset. We compiled a pan-tropical dataset containing 28,953 lianas (Z2.5cmdiam.) from studies conducted at 13 Neotropical and 11 Paleotropical dry to wet lowland tropical forests. The ranges in MAP and dry season length (DSL) (number of months with mean rainfall o100mm) represented by these datasets were 860‐7250mm/yr and 0‐7mo, respectively. Pan-tropically, liana density and basal area decreased significantly with increasing annual rainfall and increased with increasing DSL, supporting the hypotheses of Gentry and Schnitzer. Our results suggest that much of the variation in liana density and basal area in the tropics can be accounted for by the relatively simple metrics of MAP and DSL.

Published
2009

5. Seeing Central African forests through their largest trees

Author

Marc Dufrêne, Terese B. Hart, Corneille E. N. Ewango, Pierre Ploton, T. de Haulleville, Fidèle Baya, Jean-François Gillet, Sylvie Gourlet-Fleury, C De Cannière, Jean-Louis Doucet, Vincent Droissart, Gilles Dauby, Yadvinder Malhi, Duncan W. Thomas, Georges Chuyong, Jean-François Bastin, Adeline Serckx, Tariq Stévart, T. Kavali, David Kenfack, Hans Beeckman, Bonaventure Sonké, Jan Bogaert, Moses Libalah, D. Beina, C. H. Gonmadje, Pierre Couteron, Maxime Réjou-Méchain, Adeline Fayolle, Jean-Remy Makana, Danae Maniatis, Nicolas Barbier, Raphaël Pélissier, Research Unit of Landscape Ecology and Plant Production Systems, Université Libre de Bruxelles [Bruxelles] (ULB)-Université de Liège, Botanique et Modélisation de l'Architecture des Plantes et des Végétations (UMR AMAP), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [France-Sud]), Université de Liège - Gembloux, Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad), Oxford University Centre for the Environment (OUCE), University of Oxford [Oxford], Ministère des Eaux, Forêts, Chasse et Pêche, Royal Museum for Central Africa [Tervuren] (RMCA), Laboratoire de Biométrie et Biologie Evolutive - UMR 5558 (LBBE), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National de Recherche en Informatique et en Automatique (Inria)-VetAgro Sup - Institut national d'enseignement supérieur et de recherche en alimentation, santé animale, sciences agronomiques et de l'environnement (VAS)-Centre National de la Recherche Scientifique (CNRS), University of Buéa, Diversité, adaptation, développement des plantes (UMR DIADE), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [France-Sud]), Laboratoire de Physique des Solides (LPS), Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS), Entomologie fonctionnelle et évolutive - Université de Liège, Wildlife Conservation Society, Smithsonian Tropical Research Institute, Laboratoire de Botanique systématique et d'Ecologie [ENS Yaoudé], Université de Yaoundé I [Yaoundé]-École normale supérieure [ENS] - Yaoundé 1, Institut de Mécanique des Fluides de Marseille, Herbarieum et Bibliothèque de Botanique africaine, Université Libre de Bruxelles [Bruxelles] (ULB), Sud Expert Plantes, ANR-12-EBID-0002,CoForTips,Forêts du Bassin du Congo: Biodiversité, Points de Basculement et Résilience des Systèmes Écologiques et Sociaux Forestiers.(2012), Université de Liège-Université libre de Bruxelles (ULB), Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Institut National de la Recherche Agronomique (INRA)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut de Recherche pour le Développement (IRD [France-Sud]), Biens et services des écosystèmes forestiers tropicaux : l'enjeu du changement global (UPR BSEF), Ministère des Eaux, Forêts, Chasse et Pêche [République Centrafricaine], Centre National de la Recherche Scientifique (CNRS)-Université Paris-Sud - Paris 11 (UP11), Université de Yaoundé I-École normale supérieure [ENS] - Yaoundé 1, Université libre de Bruxelles (ULB), and University of Oxford

Subjects
tropical forest, Tropical and subtropical dry broadleaf forests, F40 - Écologie végétale, distributions, Tropical trees, Biodiversity, Climate change, Forests, [SDV.BID.SPT]Life Sciences [q-bio]/Biodiversity/Systematics, Phylogenetics and taxonomy, Models, Biological, size, Article, diversity, [SDV.EE.ECO]Life Sciences [q-bio]/Ecology, environment/Ecosystems, Phénomènes atmosphériques, Forest ecology, K01 - Foresterie - Considérations générales, Bosecologie en Bosbeheer, Stock (geology), Forest floor, Multidisciplinary, biomass, Ecology, Agroforestry, Forestry, dynamics, 15. Life on land, [SDV.BV.BOT]Life Sciences [q-bio]/Vegetal Biology/Botanics, PE&RC, Forest Ecology and Forest Management, Climatic change, Geography, Africa, Secondary forest, [SDE.BE]Environmental Sciences/Biodiversity and Ecology, U30 - Méthodes de recherche
Abstract

Large tropical trees and a few dominant species were recently identified as the main structuring elements of tropical forests. However, such result did not translate yet into quantitative approaches which are essential to understand, predict and monitor forest functions and composition over large, often poorly accessible territories. Here we show that the above-ground biomass (AGB) of the whole forest can be predicted from a few large trees and that the relationship is proved strikingly stable in 175 1-ha plots investigated across 8 sites spanning Central Africa. We designed a generic model predicting AGB with an error of 14% when based on only 5% of the stems, which points to universality in forest structural properties. For the first time in Africa, we identified some dominant species that disproportionally contribute to forest AGB with 1.5% of recorded species accounting for over 50% of the stock of AGB. Consequently, focusing on large trees and dominant species provides precise information on the whole forest stand. This offers new perspectives for understanding the functioning of tropical forests and opens new doors for the development of innovative monitoring strategies., SCOPUS: ar.j, info:eu-repo/semantics/published

Published
2015

6. Phylogenetic turnover along local environmental gradients in tropical forest communities

Author

Savithri Gunatilleke, Kyle E. Harms, Sumedha Madawala, Sarayudh Bunyavejchewin, Claire A. Baldeck, Hugo Navarrete, Adzmi Yaacob, David Kenfack, Mohd. N. Nur Supardi, Joseph B. Yavitt, Somboon Kiratiprayoon, Robert John, Benjamin L. Turner, Georges Chuyong, Stuart J. Davies, Renato Valencia, Duncan W. Thomas, James W. Dalling, Nimal Gunatilleke, and Steven W. Kembel

Subjects
0106 biological sciences, Ecological niche, Tropical Climate, Phylogenetic tree, Ecology, Niche, Beta diversity, Biology, Forests, 010603 evolutionary biology, 01 natural sciences, Trees, Phylogenetic diversity, Soil, Habitat, Similarity (network science), Phylogenetics, Ecology, Evolution, Behavior and Systematics, Ecosystem, Phylogeny, 010606 plant biology & botany
Abstract

While the importance of local-scale habitat niches in shaping tree species turnover along environmental gradients in tropical forests is well appreciated, relatively little is known about the influence of phylogenetic signal in species' habitat niches in shaping local community structure. We used detailed maps of the soil resource and topographic variation within eight 24-50 ha tropical forest plots combined with species phylogenies created from the APG III phylogeny to examine how phylogenetic beta diversity (indicating the degree of phylogenetic similarity of two communities) was related to environmental gradients within tropical tree communities. Using distance-based redundancy analysis we found that phylogenetic beta diversity, expressed as either nearest neighbor distance or mean pairwise distance, was significantly related to both soil and topographic variation in all study sites. In general, more phylogenetic beta diversity within a forest plot was explained by environmental variables this was expressed as nearest neighbor distance versus mean pairwise distance (3.0-10.3 % and 0.4-8.8 % of variation explained among plots, respectively), and more variation was explained by soil resource variables than topographic variables using either phylogenetic beta diversity metric. We also found that patterns of phylogenetic beta diversity expressed as nearest neighbor distance were consistent with previously observed patterns of niche similarity among congeneric species pairs in these plots. These results indicate the importance of phylogenetic signal in local habitat niches in shaping the phylogenetic structure of tropical tree communities, especially at the level of close phylogenetic neighbors, where similarity in habitat niches is most strongly preserved.

Published
2014

Catalog

Books, media, physical & digital resources
See catalog results