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1. Author Correction: Disturbance Regimes Drive The Diversity of Regional Floristic Pools Across Guianan Rainforest Landscapes

Author

Stéphane Guitet, Daniel Sabatier, Olivier Brunaux, Pierre Couteron, Thomas Denis, Vincent Freycon, Sophie Gonzalez, Bruno Hérault, Gaëlle Jaouen, Jean-François Molino, Raphaël Pélissier, Cécile Richard-Hansen, and Grégoire Vincent

Subjects
Medicine, Science
Abstract

A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has been fixed in the paper.

Published
2018
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2. Rapport d’analyse – Enquête : Les données de la recherche à l'université ParisSaclay, panorama et perspectives

Author

Mireille Brenel, Cédric Mercier, Stela Suhan, Adib Kassas, Claire Ménard, Alicia Da Mota Marques Ribeiro, Nadège Arnaud, Claire Lebreton, Maximilien Petit, Gaëlle Jaouen, Eva Legras, Annie Le Blanc, Alexia Bauville, Université Paris-Saclay, Université d'Évry-Val-d'Essonne (UEVE), Laboratoire de Mathématiques de Versailles (LMV), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Centre d'Histoire Culturelle des Sociétés Contemporaines (CHCSC), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Paris-Saclay, Ecologie des forêts de Guyane (UMR ECOFOG), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-AgroParisTech-Université de Guyane (UG)-Centre National de la Recherche Scientifique (CNRS)-Université des Antilles (UA)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), AgroParisTech, CEA- Saclay (CEA), and Commissariat à l'énergie atomique et aux énergies alternatives (CEA)

Subjects
Données de la recherche, Enquête, [SHS.INFO]Humanities and Social Sciences/Library and information sciences, Science Ouverte
Abstract

Cette enquête, proposée par l’ensemble du réseau des bibliothèques et centres de documentation et le Comité de pilotage de la Science Ouverte de l’Université Paris-Saclay en 2021, s’inscrit dans un contexte dynamique de Science Ouverte prônant l’obligation de publication des données de la recherche selon les principes FAIR (Facilement trouvable, Accessible, Interopérable, Réutilisable).L'ambition de cette enquête est de dresser un paysage le plus complet et élargi possible autour des pratiques de la recherche. Elle s’adressait à tous les chercheur·es, ingénieur·es de recherche et d’études, doctorant·es ou encore personnels administratifs de l’ensemble de l’université, en somme toutes personnes amenées à créer, manipuler, utiliser des données, et ce dans tous les établissements de l’Université.L’enquête répond à un triple objectif : - Établir un panorama des données produites au sein de l’Université- Dresser le paysage des pratiques autour des données de la recherche- Connaître les besoins des chercheur·es autour des donnéespour adapter et améliorer l'offre de services.

Published
2022

3. Large hydraulic safety margins protect Neotropical canopy rainforest tree species against hydraulic failure during drought

Author

Gaëlle Jaouen, Louis S. Santiago, Adriane Esquivel-Muelbert, Sabrina Coste, Jocelyn Cazal, Sébastien Levionnois, Camille Ziegler, Hervé Cochard, Patrick Heuret, Sylvain Delzon, Damien Bonal, Clément Stahl, Jean-Yves Goret, 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), SILVA (SILVA), Institut National de la Recherche Agronomique (INRA)-Université de Lorraine (UL)-AgroParisTech, Biodiversité, Gènes & Communautés (BioGeCo), Institut National de la Recherche Agronomique (INRA)-Université de Bordeaux (UB), Laboratoire de Physique et Physiologie Intégratives de l’Arbre en environnement Fluctuant (PIAF), Institut National de la Recherche Agronomique (INRA)-Université Clermont Auvergne [2017-2020] (UCA [2017-2020]), University of Leeds, University of Birmingham [Birmingham], Botanique et Modélisation de l'Architecture des Plantes et des Végétations (UMR AMAP), 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]), University of California, Smithsonian Tropical Research Institute, Institut National de la Recherche Agronomique (INRA)-AgroParisTech-Université de Lorraine (UL), Université de Bordeaux (UB)-Institut National de la Recherche Agronomique (INRA), Laboratoire de Physique et Physiologie Intégratives de l’Arbre en environnement Fluctuant - Clermont Auvergne (PIAF), Institut National de la Recherche Agronomique (INRA)-Université Clermont Auvergne (UCA), 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]), Smithsonian Institution, and University of California (UC)

Subjects
0106 biological sciences, Canopy, Amazon rainforest, Water potential, [SDV]Life Sciences [q-bio], Turgor pressure, Rainforest, [SDV.BID.SPT]Life Sciences [q-bio]/Biodiversity/Systematics, Phylogenetics and taxonomy, 010603 evolutionary biology, 01 natural sciences, Turgor loss point, [SDV.EE.ECO]Life Sciences [q-bio]/Ecology, environment/Ecosystems, Hydraulic conductivity, Dry season, Hydraulic safety margins, Embolism resistance, Ecology, Resistance (ecology), fungi, Xylem, Tropics, food and beverages, Forestry, 15. Life on land, [SDV.BV.BOT]Life Sciences [q-bio]/Vegetal Biology/Botanics, Agronomy, Environmental science, [SDE.BE]Environmental Sciences/Biodiversity and Ecology, 010606 plant biology & botany
Abstract

Key message Abundant Neotropical canopy-tree species are more resistant to drought-induced branch embolism than what is currently admitted. Large hydraulic safety margins protect them from hydraulic failure under actual drought conditions. Context Xylem vulnerability to embolism, which is associated to survival under extreme drought conditions, is being increasingly studied in the tropics, but data on the risk of hydraulic failure for lowland Neotropical rainforest canopy-tree species, thought to be highly vulnerable, are lacking. Aims The purpose of this study was to gain more knowledge on species drought-resistance characteristics in branches and leaves and the risk of hydraulic failure of abundant rainforest canopy-tree species during the dry season. Methods We first assessed the range of branch xylem vulnerability to embolism using the flow-centrifuge technique on 1-m-long sun-exposed branches and evaluated hydraulic safety margins with leaf turgor loss point and midday water potential during normal- and severe-intensity dry seasons for a large set of Amazonian rainforest canopy-tree species. Results Tree species exhibited a broad range of embolism resistance, with the pressure threshold inducing 50% loss of branch hydraulic conductivity varying from − 1.86 to − 7.63 MPa. Conversely, we found low variability in leaf turgor loss point and dry season midday leaf water potential, and mostly large, positive hydraulic safety margins. Conclusions Rainforest canopy-tree species growing under elevated mean annual precipitation can have high resistance to embolism and are more resistant than what was previously thought. Thanks to early leaf turgor loss and high embolism resistance, most species have a low risk of hydraulic failure and are well able to withstand normal and even severe dry seasons.

Published
2019

4. Coordinated community structure among trees, fungi and invertebrate groups in Amazonian rainforests

Author

Christopher Baraloto, Jason Vleminckx, Gaëlle Jaouen, Julien Engel, Thibaud Decaëns, Pascal Petronelli, Aurélie Dourdain, Jérôme Orivel, Mélanie Fichaux, Heidy Schimann, Mélanie Roy, Emmanuel Lapied, Vincent Vedel, 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), Florida International University [Miami] (FIU), Centre d’Ecologie Fonctionnelle et Evolutive (CEFE), Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-École pratique des hautes études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut National de la Recherche Agronomique (INRA)-Université Paul-Valéry - Montpellier 3 (UPVM)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut de Recherche pour le Développement (IRD [France-Sud]), Evolution et Diversité Biologique (EDB), 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, Taxonomia International Foundation, Botanique et Modélisation de l'Architecture des Plantes et des Végétations (UMR AMAP), 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]), Département Environnements et Sociétés (Cirad-ES), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad), Florida International University (FIU), Université Paul-Valéry - Montpellier 3 (UM3)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-École pratique des hautes études (EPHE)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [France-Sud])-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), 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 Paul-Valéry - Montpellier 3 (UPVM)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-École Pratique des Hautes Études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [France-Sud])-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), and Université de Toulouse (UT)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)

Subjects
0301 basic medicine, Amazonian, lcsh:Medicine, forêt tropicale, [SDV.BID.SPT]Life Sciences [q-bio]/Biodiversity/Systematics, Phylogenetics and taxonomy, Trees, Interactions biologiques, Soil, 0302 clinical medicine, Taxonomic rank, lcsh:Science, Phylogeny, Trophic level, Multidisciplinary, Ecology, Community structure, Edaphic, Biodiversity, [SDV.BV.BOT]Life Sciences [q-bio]/Vegetal Biology/Botanics, Tropical ecology, Écologie des populations, French Guiana, L20 - Écologie animale, P01 - Conservation de la nature et ressources foncières, Communauté végétale, Assembly rules, Rainforest, F40 - Écologie végétale, Distribution géographique, Invertébré, Champignon, Biology, Arbre, Article, 03 medical and health sciences, [SDV.EE.ECO]Life Sciences [q-bio]/Ecology, environment/Ecosystems, Animals, Community ecology, Ecosystem, Invertebrate, Tropical Climate, Ants, lcsh:R, Fungi, 15. Life on land, Invertebrates, biodiversité forestière, 030104 developmental biology, lcsh:Q, [SDE.BE]Environmental Sciences/Biodiversity and Ecology, 030217 neurology & neurosurgery
Abstract

Little is known regarding how trophic interactions shape community assembly in tropical forests. Here we assess multi-taxonomic community assembly rules using a rare standardized coordinated inventory comprising exhaustive surveys of five highly-diverse taxonomic groups exerting key ecological functions: trees, fungi, earthworms, ants and spiders. We sampled 36 1.9-ha plots from four remote locations in French Guiana including precise soil measurements, and we tested whether species turnover was coordinated among groups across geographic and edaphic gradients. All species group pairs exhibited significant compositional associations that were independent from soil conditions. For some of the pairs, associations were also partly explained by soil properties, especially soil phosphorus availability. Our study provides evidence for coordinated turnover among taxonomic groups beyond simple relationships with environmental factors, thereby refining our understanding regarding the nature of interactions occurring among these ecologically important groups.

Published
2019

5. Author Correction: Disturbance Regimes Drive The Diversity of Regional Floristic Pools Across Guianan Rainforest Landscapes

Author

Gaëlle Jaouen, Vincent Freycon, Olivier Brunaux, Pierre Couteron, Raphaël Pélissier, Grégoire Vincent, Thomas Denis, Cécile Richard-Hansen, Bruno Hérault, Stéphane Guitet, Sophie Gonzalez, Daniel Sabatier, and Jean-François Molino

Subjects
0301 basic medicine, Multidisciplinary, Disturbance (geology), Ecology, Science, media_common.quotation_subject, Rainforest, 15. Life on land, Floristics, 03 medical and health sciences, 030104 developmental biology, Geography, ComputingMethodologies_DOCUMENTANDTEXTPROCESSING, Medicine, Diversity (politics), media_common
Abstract

A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has been fixed in the paper.

Published
2018

6. In Situ Reference Datasets From the TropiSAR and AfriSAR Campaigns in Support of Upcoming Spaceborne Biomass Missions

Author

Lisa Korte, Thuy Le Toan, John R. Poulsen, Katharine Abernethy, Hervé Memiaghe, Pulchérie Bissiengou, David Kenfack, Bruno Hérault, Sassan Saatchi, Lee J. T. White, Klaus Scipal, Stuart J. Davies, Antonio Ferraz, Gaëlle Jaouen, Maxime Réjou-Méchain, Simon L. Lewis, Alfonso Alonso, Yadvinder Malhi, Shengli Tao, Nicolas Barbier, Tania Casal, Ludovic Villard, Kathryn J. Jeffery, Jérôme Chave, Grégoire Vincent, Nicolas Labrière, Evolution et Diversité Biologique (EDB), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), European Space Research and Technology Centre (ESTEC), European Space Agency (ESA), Centre d'études spatiales de la biosphère (CESBIO), 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), University of Stirling, Smithsonian Conservation Biology Institute, 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]), Centre national de la recherche scientifique et technologique (CENAREST), CENAREST, Institut de Pharmacopée et de Médecine Traditionnelle (IPHAMETRA), Smithsonian Tropical Research Institute, California Institute of Technology (CALTECH), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad), 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), University College of London [London] (UCL), University of Oxford [Oxford], Duke University [Durham], Institut de Recherche pour le Développement (IRD), 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, 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), 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), 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]), and 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)

Subjects
Atmospheric Science, 010504 meteorology & atmospheric sciences, 0211 other engineering and technologies, Biomass, 02 engineering and technology, [SDV.BID.SPT]Life Sciences [q-bio]/Biodiversity/Systematics, Phylogenetics and taxonomy, 01 natural sciences, Electronic mail, remote sensing, Tropical forest, Environmental monitoring, K01 - Foresterie - Considérations générales, Biomasse, Forêt tropicale humide, Ecology, Vegetation, Remote sensing, [SDV.BV.BOT]Life Sciences [q-bio]/Vegetal Biology/Botanics, Collecte de données, P01 - Conservation de la nature et ressources foncières, ecology, synthetic aperture radar, Carbone, Télédétection, Surface topography, [SDV.EE.ECO]Life Sciences [q-bio]/Ecology, environment/Ecosystems, Deforestation, vegetation, Mesure, Computers in Earth Sciences, 021101 geological & geomatics engineering, 0105 earth and related environmental sciences, environmental monitoring, Forest inventory, 15. Life on land, surface topography, Carbon, 13. Climate action, Synthetic aperture radar SAR, Data quality, Environmental science, Satellite, U30 - Méthodes de recherche, [SDE.BE]Environmental Sciences/Biodiversity and Ecology
Abstract

International audience; Tropical forests are a key component of the global carbon cycle. Yet, there are still high uncertainties in forest carbon stock and flux estimates, notably because of their spatial and temporal variability across the tropics. Several upcoming spaceborne missions have been designed to address this gap. High-quality ground data are essential for accurate calibration/validation so that spaceborne biomass missions can reach their full potential in reducing uncertainties regarding forest carbon stocks and fluxes. The BIOMASS mission, a P-band SAR satellite from the European Space Agency (ESA), aims at improving carbon stock mapping and reducing uncertainty in the carbon fluxes from deforestation, forest degradation, and regrowth. In situ activities in support of the BIOMASS mission were carried out in French Guiana and Gabon during the TropiSAR and AfriSAR campaigns. During these campaigns, airborne P-band SAR, forest inventory, and lidar data were collected over six study sites. This paper describes the methods used for forest inventory and lidar data collection and analysis, and presents resulting plot estimates and aboveground biomass maps. These reference datasets along with intermediate products (e.g., canopy height models) can be accessed through ESA's Forest Observation System and the Dryad data repository and will be useful for BIOMASS but also to other spaceborne biomass missions such as GEDI, NISAR, and Tandem-L for calibration/validation purposes. During data quality control and analysis, prospects for reducing uncertainties have been identified, and this paper finishes with a series of recommendations for future tropical forest field campaigns to better serve the remote sensing community.

Published
2018
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7. Ants of French Guiana: 16S rRNA sequence dataset

Author

Gaëtan Rongier, Audrey Sagne, Sandrine Etienne, Frederic Petitclerc, Gaelle Jaouen, Jerome Murienne, and Jerome Orivel

Subjects
DNA sequencing, 16S rRNA, molecular identification, Biology (General), QH301-705.5
Abstract

This dataset represents a reference library of DNA sequences for ants from French Guiana. A total of 3931 new sequences from the 16S rRNA gene has been generated. The reference library covers 344 species distributed in 57 genera. Overall, 3920 sequences have been assigned at the species level and 11 at the genus level. All these sequences were submitted to DDBJ/EMBL/GenBank databases in the Bioproject: PRJNA779056: 16S French Guiana Ants (Hymenoptera: Formicidae), sequence identifier KFFS00000000.

Published
2023
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8. Black Curassow habitat relationships in terra firme forests of the GuianaShield: A multiscale approach

Author

Olivier Brunaux, Stéphane Guitet, Gaëlle Jaouen, Bruno Hérault, Cécile Richard-Hansen, Thomas Denis, Office National de la Chasse et de la Faune Sauvage [Kourou, Guyane], Institut National de la Recherche Agronomique (INRA)-AgroParisTech-Université de Guyane (UG)-Centre National de la Recherche Scientifique (CNRS)-Université des Antilles (Pôle Guadeloupe), Université des Antilles (UA)-Université des Antilles (UA), 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), ONF Guyane, Réserve de Montabo, Office National des Forêts (ONF), 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]), Funding was provided over many yearsby ONCFS and various external sources: the EU HABITATand CHASSE programs, the French Ministry for OverseasTerritories, the French Ministry of the Environment (ECOTROPprogram), the Parc Amazonien de Guyane (PAG),Office National des Forêts, and the CNRS (Centre national dela recherche scientifique) Nouragues program. T.D. and B.H.were supported by a grant from the Investing for the Futureprogram (Investissements d’Avenir) managed by the FrenchNational Research Agency (Agence nationale de la recherche,CEBA, ref. ANR-10-LABX-0025)., ANR-10-LABX-0025,CEBA,CEnter of the study of Biodiversity in Amazonia(2010), Université des Antilles (Pôle Guadeloupe), Université des Antilles (UA)-Université des Antilles (UA)-Institut National de la Recherche Agronomique (INRA)-Université de Guyane (UG)-Institut Pasteur de la Guyane, Réseau International des Instituts Pasteur (RIIP)-Réseau International des Instituts Pasteur (RIIP)-Centre National de la Recherche Scientifique (CNRS)-AgroParisTech, ANR-10-LABX-25-01/10-LABX-0025,CEBA,CEnter of the study of Biodiversity in Amazonia(2010), 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)-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]), and Institut National de la Recherche Agronomique (INRA)-Université de Guyane (UG)-Centre National de la Recherche Scientifique (CNRS)-AgroParisTech-Université des Antilles (Pôle Guadeloupe)

Subjects
0106 biological sciences, 010504 meteorology & atmospheric sciences, terra firme forests, hunting, [SDV]Life Sciences [q-bio], habitat, Crax, forêt tropicale, 01 natural sciences, Population density, K01 - Foresterie - Considérations générales, ComputingMilieux_MISCELLANEOUS, biology, Ecology, espèce en danger, Black curassow, Cracidae, Lauraceae, Espèce protégée, Geography, Habitat, L20 - Écologie animale, Distribution géographique, Topographie, Rainforest, 010603 evolutionary biology, Ecology, Evolution, Behavior and Systematics, 0105 earth and related environmental sciences, Paysage, Rapace, Composition botanique, Crax alector, Oiseau, multiscale analysis, 15. Life on land, species–habitat relationships, biology.organism_classification, Conservation status, Animal Science and Zoology, Écologie animale
Abstract

International audience; The Black Curassow (Crax alector) is a large game bird with Vulnerable conservation status found in north-central South America. We examined its distributional pattern across French Guiana using a large number of environmental descriptors at 3 scales of analysis: landscape, forest type, and microhabitat. We used a hierarchical model with temporary emigration and imperfect detection for data collected by standard distance sampling methods at 35 study sites. At the landscape scale, Black Curassow density decreased with hunting pressure and increased with steeper slopes in both hunted and unhunted areas. Topography appeared to be a good proxy for Black Curassow ecological requirements and probably reflected habitat quality. At the forest scale, population density was negatively correlated with the abundance of palms and Mimosoideae and positively correlated with the abundance of Lauraceae. Botanical families did not directly influence Black Curassow distribution, but rather determined spatial patterns by being markers of a particular forest type. At the microhabitat scale, Black Curassows used hilltops more frequently than other parts of the local topographical gradient. Our multiscale analysis shows that this species' distribution can be explained by biotic or abiotic conditions, regardless of the scale. For conservation, we recommend maintaining connectivity between Black Curassow populations separated by hunted areas. Our predicted densities could be used to adapt hunting quotas across French Guiana's forests. We show that combining field and remote sensing data helps to understand the ecological processes responsible for Black Curassow habitat relationships.

Published
2016

9. Étude comparative de 3 tests de « copies de figures » utilisés chez l'enfant : Beery VMI, NEPSY et DTVP-2

Author

Cécilia Galbiati, Valérie Barray, Anne-Sophie Deborde, Marie Palu, Gaëlle Jaouen, and Gwenaëlle Lefévère

Subjects
School age child, Cultural environment, Psychology, Humanities, NEPSY
Abstract

Resume Dans notre pratique d’ergotherapeutes, nous relevons frequemment des differences notables de resultats d’un meme patient a trois tests de copie de figures, utilisees en pediatrie dans le domaine des troubles d’apprentissage.Cette etude compare ces trois epreuves : celle du « Beery-Buktenica Developmental Test of Visual-Motor Integration » 4e version de Beery et Buktenica, 1997 (Beery VMI), celle de la « NEPSY, bilan neuropsychologique de l’enfant » de Korkman, Kirk et Kemp, 2003 (Nepsy) et celle du « Developmental Test of Visual Perception-2 » de Hammill, Pearson et Voress, 1993 (DTVP-2). Leur presentation detaillee montre des differences : materiels, proprietes psychometriques, notations et etalonnages. Une comparaison des resultats obtenus a ces trois epreuves aupres de 90 enfants de 6 a 10 ans est realisee. Apres normalisation des donnees, l’etude de correlation montre un lien unissant ces trois epreuves. Mais l’analyse de variance multivariee par mesures repetees revele une difference significative entre les moyennes. Plusieurs hypotheses sont proposees pour expliquer les differences retrouvees. Afin d’eviter le biais introduit par les differences culturelles entre enfants americains et francais, les auteurs preconisent l’utilisation de l’epreuve de « Copie de figures » de la NEPSY pour comparer la performance du sujet teste avec celles de ses pairs. Celle du Beery VMI est recommandee quand il s’agit d’evaluer la performance de l’enfant dans une trajectoire developpementale.

Published
2010

10. How to determine sapling buckling risk with only a few measurements

Author

Meriem Fournier, Gaëlle Jaouen, Tancrède Alméras, Catherine Coutand, Ecologie des forêts de Guyane (ECOFOG), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Université des Antilles et de la Guyane (UAG)-AgroParisTech-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Physique et Physiologie Intégratives de l'Arbre Fruitier et Forestier (PIAF), Institut National de la Recherche Agronomique (INRA)-Université Blaise Pascal - Clermont-Ferrand 2 (UBP), Laboratoire d'Etudes des Ressources Forêt-Bois (LERFoB), Institut National de la Recherche Agronomique (INRA)-AgroParisTech, and AgroParisTech-Institut National de la Recherche Agronomique (INRA)

Subjects
0106 biological sciences, Sample (statistics), Plant Science, Biology, 010603 evolutionary biology, 01 natural sciences, STEM FORM, BIOMECANIQUE, Statistics, Genetics, Range (statistics), Sensitivity (control systems), Ecology, Evolution, Behavior and Systematics, SAPLING, TROPICAL RAIN FOREST, Ecology, CRITICAL BUCKLING HEIGHT, RISK FACTOR, Risk factor (finance), Variance (accounting), [SDV.BV.BOT]Life Sciences [q-bio]/Vegetal Biology/Botanics, BIOMECHANICS, FRENCH GUIANA, Tree (data structure), Buckling, Trait, TRUNK VOLUME, 010606 plant biology & botany
Abstract

Tree buckling risk (actual height/critical buckling height) is an important biomechanical trait of plant growth strategies, and one that contributes to species coexistence. To estimate the diversity of this trait among wide samples, a method that minimizes damage to the plants is necessary. On the basis of the rarely used, complete version of Greenhill's model (1881, Proceedings of the Cambridge Philosophical Society 4(2): 65-73), we precisely measured all the necessary parameters on a sample of 236 saplings of 16 species. Then, using sensitivity (variance) analysis, regressions between successive models for risk factors and species ranks and the use of these models on samples of self- and nonself-supporting saplings, we tested different degrees of simplification up to the most simple and widely used formula that assumes that the tree is a cylindrical homogeneous pole. The size factor had the greatest effect on buckling risk, followed by the form factor and the modulus of elasticity of the wood. Therefore, estimates of buckling risk must consider not only the wood properties but especially the form factor. Finally, we proposed a simple but accurate method of assessing tree buckling risk that is applicable to a wide range of samples and that requires mostly nondestructive measurements.

Published
2007

11. Landscape patterns influence communities of medium- to large-bodied vertebrates in undisturbed terra firme forests of French Guiana

Author

Stéphane Guitet, Thomas Denis, Cécile Richard-Hansen, Olivier Brunaux, Gaëlle Jaouen, Eric Marcon, Office National de la Chasse et de la Faune Sauvage [Kourou, Guyane], AgroParisTech-Université de Guyane (UG)-Centre National de la Recherche Scientifique (CNRS)-Université des Antilles (Pôle Guadeloupe), Université des Antilles (UA)-Université des Antilles (UA)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), 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), Office National de la Chasse et de la Faune Sauvage, 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), Office National des Forêts (ONF), Botanique et Modélisation de l'Architecture des Plantes et des Végétations (UMR AMAP), and 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])

Subjects
Diversity, Ecology, Environmental heterogeneity, Landscape ecology, Beta diversity, Amazonian forest, 15. Life on land, [SDV.BV.BOT]Life Sciences [q-bio]/Vegetal Biology/Botanics, Animal communities, [SDV.BID.SPT]Life Sciences [q-bio]/Biodiversity/Systematics, Phylogenetics and taxonomy, French Guiana, Diversity index, Geography, [SDV.EE.ECO]Life Sciences [q-bio]/Ecology, environment/Ecosystems, Habitat, Abundance (ecology), Forest ecology, Species-habitat association, [SDE.BE]Environmental Sciences/Biodiversity and Ecology, Relative species abundance, Ecology, Evolution, Behavior and Systematics
Abstract

Whereas broad-scale Amazonian forest types have been shown to influence the structure of the communities of medium- to large-bodied vertebrates, their natural heterogeneity at smaller scale or within the terra firme forests remains poorly described and understood. Diversity indices of such communities and the relative abundance of the 21 most commonly observed species were compared from standardized line-transect data across 25 study sites distributed in undisturbed forests in French Guiana. We first assessed the relevance of a forest typology based on geomorphological landscapes to explain the observed heterogeneity. As previously found for tree beta-diversity patterns, this new typology proved to be a non-negligible factor underlying the beta diversity of the communities of medium- to large bodied vertebrates in French Guianan terra firme forests. Although the species studied are almost ubiquitous across the region, they exhibited habitat preferences through significant variation in abundance and in their association index with the different landscape types. As terra firme forests represent more than 90% of the Amazon basin, characterizing their heterogeneity – including faunal communities – is a major challenge in neotropical forest ecology.

Published
2015

12. Geomorphological landscape features explain floristic patterns in French Guiana rainforest

Author

Stéphane Guitet, Daniel Sabatier, Raphaël Pélissier, Gaëlle Jaouen, Olivier Brunaux, 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]), Office National des Forêts (ONF), 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), European Union’s PO-FEDER program (HABITATS), 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]), and Recherche et Développement - Réserve de Montabo

Subjects
0106 biological sciences, 010504 meteorology & atmospheric sciences, Landscapes, [SDV]Life Sciences [q-bio], Species distribution, Biodiversity, Rainforest, 010603 evolutionary biology, 01 natural sciences, Abundance (ecology), Transect, Ecology, Evolution, Behavior and Systematics, 0105 earth and related environmental sciences, Nature and Landscape Conservation, Ecology, Forest dynamics, Geodiversity, Tree community, Geomorphology, 15. Life on land, Geography, Spatial ecology, Tropical rainforest
Abstract

Geomorphic landscape features have been suggested as indicators of forest diversity. However, their explanatory power has not yet been explicitly tested at a regional scale in tropical rainforest. We used forest inventories conducted according to a stratified sampling design (3,132 plots in 111 transects at 33 sites) and holistic multi-scale geomorphological mapping derived from a Shuttle Radar Topography Mission digital elevation model to describe and explain spatial patterns in floristic composition across French Guiana (80,000 km(2)). We measured and identified 123,906 trees with DBH a parts per thousand yen20 cm and used constrained and unconstrained ordinations to analyze variations in the abundance of 221 taxa and 51 families. Variance partitioning and variograms were used to detect spatial patterns in species composition, compare the explanatory power of spatial and environmental factors, and select the variables that best explain forest composition. Strong floristic patterns corresponded to a major latitudinal gradient and significant sub-regional floristic structure. Geomorphological landscapes shaped by historic climate fluctuations and major geological events successfully captured these patterns and explained the variation in abundance of 80 taxa, corresponding to 65 % of the inventoried trees. Our findings suggest that long-term forest dynamics are under substantial "geomorphographic control". A geomorphological perspective on landscapes that incorporates current and past environmental filters and historical biogeographical processes could thus be used more systematically in tropical regions for regional planning and forest conservation.

Published
2015

13. Mapping Radial,Tangential and Longitudinal Shrinkages and Relation to Tension Wood in Discs of the Tropical Tree Symphonia globulifera

Author

Bruno Clair, Meriem Fournier, Jacques Beauchêne, Gaëlle Jaouen, Ecologie des forêts de Guyane (ECOFOG), Ecole Nationale du Génie Rural, des Eaux et des Forêts (ENGREF)-Institut National de la Recherche Agronomique (INRA)-Université des Antilles et de la Guyane (UAG)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Mécanique et Génie Civil (LMGC), and Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)

Subjects
[SPI.OTHER]Engineering Sciences [physics]/Other, K50 - Technologie des produits forestiers, 0106 biological sciences, [SDV.OT]Life Sciences [q-bio]/Other [q-bio.OT], [PHYS.PHYS.PHYS-BIO-PH]Physics [physics]/Physics [physics]/Biological Physics [physics.bio-ph], Symphonia, 01 natural sciences, [PHYS.MECA.MEMA]Physics [physics]/Mechanics [physics]/Mechanics of materials [physics.class-ph], Biomaterials, [SDV.SA.SF]Life Sciences [q-bio]/Agricultural sciences/Silviculture, forestry, 010608 biotechnology, [SPI.MECA.MEMA]Engineering Sciences [physics]/Mechanics [physics.med-ph]/Mechanics of materials [physics.class-ph], Symphonia globulifera L.f, [PHYS.MECA.BIOM]Physics [physics]/Mechanics [physics]/Biomechanics [physics.med-ph], Symphonia globulifera, Composite material, Anisotropy, Shrinkage, 040101 forestry, biology, Tension wood, [SPI.MECA.BIOM]Engineering Sciences [physics]/Mechanics [physics.med-ph]/Biomechanics [physics.med-ph], Industrial chemistry, 04 agricultural and veterinary sciences, 15. Life on land, biology.organism_classification, Tension (geology), 0401 agriculture, forestry, and fisheries, Drying shrinkage, Tree (set theory)
Abstract

Summary A method for measuring shrinkage resulting from drying in the three anisotropic directions is developed and tested. Measurements are performed on sawn discs, a technique which simplifies preparation and enables large numbers of measurements. Shrinkage values can be represented as a map of the disc surface. The results indicate that comparisons between shrinkage distribution and tension wood distribution on the discs show a clear relationship and can be measured with relatively high accuracy in reference to the “shrinkage map”. In the long term, this method could be useful in the timber industry as a means for choosing the direction in which logs are cut depending on their type of wood composition.

Published
2003

14. Habitats : décrire et cartographier la diversité des forêts de Guyane

Author

Stéphane Guitet, Olivier Brunaux, Gaëlle Jaouen, Cecile Richard-Hansen, Sophie Gonzalez Portero, Daniel Sabatier, Raphaël Pélissier, 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]), Office National des Forêts (ONF), Ecologie des forêts de Guyane (ECOFOG), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Université des Antilles et de la Guyane (UAG)-AgroParisTech-Centre National de la Recherche Scientifique (CNRS), Office National de la Chasse et de la Faune Sauvage, and 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])

Subjects
[SDV]Life Sciences [q-bio]
Abstract

En 2009, l’ONF s’associait à l’ONCFS, au Parc Amazonien de Guyane, à l’UMR EcoFoG et à l’Herbier de Cayenne, dans un vaste programme de recherche, intitulé HABITATS. Son objectif : étudier les relations entre sol, végétation et grande faune pour définir une typologie des habitats forestiers de terre ferme, qui couvrent plus de 80 % du territoire. Retour sur le programme et ses acquis

Published
2014

15. Integrative biomechanics for tree ecology: beyond wood density and strength

Author

Gaëlle Jaouen, Jana Dlouha, Meriem Fournier, Tancrède Alméras, Laboratoire d'Etudes des Ressources Forêt-Bois (LERFoB), AgroParisTech-Institut National de la Recherche Agronomique (INRA), Ecologie des forêts de Guyane (ECOFOG), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Université des Antilles et de la Guyane (UAG)-AgroParisTech-Centre National de la Recherche Scientifique (CNRS), Mécanique de l'Arbre et du Bois (MAB), Laboratoire de Mécanique et Génie Civil (LMGC), Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), and French National Research Agency (ANR) through the Laboratory of Excellence ARBRE [ANR-12- LABXARBRE-01]

Subjects
0106 biological sciences, Compressive Strength, Physiology, Wind, Plant Science, Ecological strategy, Biology, Models, Biological, 010603 evolutionary biology, 01 natural sciences, Trees, Gravitropism, Size, Computer Simulation, Biomechanics, [PHYS.MECA.BIOM]Physics [physics]/Mechanics [physics]/Biomechanics [physics.med-ph], Functional ecology, Ecology, Plant Stems, Shape, [SPI.MECA.BIOM]Engineering Sciences [physics]/Mechanics [physics.med-ph]/Biomechanics [physics.med-ph], 15. Life on land, Wood, Biomechanical Phenomena, Phenotype, Basic density, Trait, Allometry, 010606 plant biology & botany
Abstract

International audience; Functional ecology has long considered the support function as important, but its biomechanical complexity is only just being elucidated. We show here that it can be described on the basis of four biomechanical traits, two safety traits against winds (SW) and self-buckling (SB), and two motricity traits involved in sustaining an upright position, tropic motion velocity (MV) and posture control (PC). All these traits are integrated at the tree scale, combining tree size and shape together with wood properties. The assumption of trait constancy has been used to derive allometric scaling laws, but it was more recently found that observing their variations among environments and functional groups, or during ontogeny, provides more insights into adaptive syndromes of tree shape and wood properties. However, over-simplified expressions have often been used, possibly concealing key adaptive drivers. An extreme case of over-simplification is the use of wood basic density as a proxy for safety. Actually, since wood density is involved in stiffness, loads and construction costs, the impact of its variations on safety is non-trivial. Moreover, other wood features, especially the microfibril angle (MFA), are also involved. Furthermore, wood is not only stiff and strong, but it also acts as a motor for MV and PC. The relevant wood trait for that is maturation strain asymmetry. Maturation strains vary with cell wall characteristics such as MFA, rather than with wood density. Finally, the need for further studies about the ecological relevance of branching patterns, motricity traits and growth responses to mechanical loads is discussed.

Published
2013

17. Thigmomorphogénèse et effet de la lumière dans les stratégies biomécaniques de croissance de jeunes arbres de deux espèces de forêt tropicale humide

Author

Meriem Fournier, Tancrède Almeras, Gaëlle Jaouen, Ecologie des forêts de Guyane (ECOFOG), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Université des Antilles et de la Guyane (UAG)-AgroParisTech-Centre National de la Recherche Scientifique (CNRS), Mécanique de l'Arbre et du Bois (MAB), Laboratoire de Mécanique et Génie Civil (LMGC), Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), ANR: woodiversity,woodiversity, Jaouen, Gaëlle, woodiversity, and ANR-05-BDIV-0012,Woodiversity,Diversité des structures de bois et analyse biophysique des stratégies écologiques des ligneux en forêt tropicale humide(2005)

Subjects
0106 biological sciences, forêt tropicale humide, Forest management, French Guiana---biomécanique, biomechanics, thigmomorphogenesis, height growth strategies, tropical rain forest, French Guiana, 010603 evolutionary biology, 01 natural sciences, Ecosystems, Staking, [SDV.EE.ECO]Life Sciences [q-bio]/Ecology, environment/Ecosystems, [SDV.SA.SF]Life Sciences [q-bio]/Agricultural sciences/Silviculture, forestry, Guyane française, stratégies de croissance en hauteur, Arbol, [PHYS.MECA.BIOM]Physics [physics]/Mechanics [physics]/Biomechanics [physics.med-ph], biomécanique de l'arbre, computer.programming_language, Ecology, biology, Tachigali, Tropics, [SPI.MECA.BIOM]Engineering Sciences [physics]/Mechanics [physics.med-ph]/Biomechanics [physics.med-ph], Forestry, Understory, Biomécanique (Physique), 15. Life on land, biology.organism_classification, croissance, thigmomorphogénèse, Ecosystèmes, guyane, Thigmomorphogenesis, computer, 010606 plant biology & botany, Tropical rainforest
Abstract

• In the dense tropical rainforest understorey, saplings exhibit different growth strategies aiming at reaching light levels better fitting their ecology. Investing mainly in height growth, at the expense of their width, a lot are close to mechanical instability. Tachigali melinonii, a long living heliophilic tree species, is frequently observed to be extremely slender and supported by neighbours. Such observations suggest an active growth control through the perception of mechanical environment. [br/] • Mechanical environment or light availability, which one is the most influent on growth and slenderness (H/D)? To test this question, we recorded growth of control and staked saplings of two species with contrasting habits and ecology: T. melinonii, and Dicorynia guianensis, along a natural light gradient. [br/] • Dicorynia, the more stable, responded more clearly to the staking treatment, showing slenderness increase when light is available, whereas for Tachigali, only light availability governed growth. [br/] • For Tachigali, growth allocation is mainly governed by light availability and ontogeny, whereas Dicorynia is probably similar to the average tree strategy, using the thigmomorphogenetic physiological process to control its stability., • Dans le sous-bois dense tropical humide, les jeunes arbres développent différentes stratégies de croissance pour atteindre des niveaux de lumière mieux adaptés à leur écologie. En investissant massivement dans la croissance en hauteur aux dépens de leur épaisseur, beaucoup sont proches de la non-autoportance. Tachigali melinonii, héliophile à vie longue, est fréquemment observée extrêmement élancée, supportée par ses voisins. Ceci suggère un contrôle actif de la croissance par la perception de l’environnement mécanique.[br/] • Qui, de l’environnement mécanique ou de la disponibilité de la lumière influence le plus la croissance et l’élancement ? Nous avons observé la croissance de jeunes T. melinonii et Dicorynia guianensis (plus sciaphile), tuteurés ou non, le long d’un gradient naturel de lumière.[br/] • Dicorynia, mécaniquement plus stable, est plus réactive aux tuteurs, investissant la biomasse produite dans la croissance en hauteur. La croissance en hauteur de Tachigali est uniquement gouvernée par la lumière disponible.[br/] • Pour Tachigali, la disponibilité de la lumière et le stade ontogénique gouvernent principalement l’allocation de croissance. Dicorynia, comme probablement beaucoup d’espèces, utilise la thigmomorphogénèse pour contrôler sa stabilité.

Published
2010

18. Functional diversity in gravitropic reaction among tropical seedlings in relation to ecological and developmental traits

Author

Gaëlle Jaouen, Tancrède Alméras, Jacques Beauchêne, Morgane Derycke, Meriem Fournier, Mécanique de l'Arbre et du Bois (MAB), Laboratoire de Mécanique et Génie Civil (LMGC), Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Ecologie des forêts de Guyane (ECOFOG), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Université des Antilles et de la Guyane (UAG)-AgroParisTech-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Etudes des Ressources Forêt-Bois (LERFoB), and AgroParisTech-Institut National de la Recherche Agronomique (INRA)

Subjects
0106 biological sciences, Eperua, Light, Physiology, Reaction wood, Biodiversity, F62 - Physiologie végétale - Croissance et développement, Plant Science, Functional diversity, F50 - Anatomie et morphologie des plantes, 01 natural sciences, K01 - Foresterie - Considérations générales, Tropical rainforest, Biomechanics, Forêt tropicale humide, Port de la plante, Expérimentation, Enquête, biology, U10 - Informatique, mathématiques et statistiques, Ecology, [SPI.MECA.BIOM]Engineering Sciences [physics]/Mechanics [physics.med-ph]/Biomechanics [physics.med-ph], Cecropia obtusifolia, Eperua falcata, Plants, French Guiana, Anatomie végétale, Interception, Modèle mathématique, Woody plant, F40 - Écologie végétale, Gravitropism, Plant Development, 010603 evolutionary biology, Quantitative Trait, Heritable, Tachinidae, Botany, Bois de réaction, [PHYS.MECA.BIOM]Physics [physics]/Mechanics [physics]/Biomechanics [physics.med-ph], Virola, Croissance, Ecosystem, Tropical Climate, Morphologie végétale, 15. Life on land, biology.organism_classification, Carapidae, Plant morphology, Seedling, Seedlings, Propriété mécanique, Dimension, Gravimétrie, 010606 plant biology & botany
Abstract

International audience; Gravitropism is necessary for plants to control the orientation of their axes while they grow in height. In woody plants, stem re-orientations are costly because they are achieved through diameter growth. The functional diversity of gravitropism was studied to check if the mechanisms involved and their efficiency may contribute to the differentiation of height growth strategies between forest tree species at the seedling stage. Seedlings of eight tropical species were grown tilted in a greenhouse, and their up-righting movement and diameter growth were measured during three months. Morphological, anatomical and biomechanical traits were measured at the end of the survey. Curvature analysis was used to analyse the up-righting response along the stems. Variations in stem curvature depend on diameter growth, size effects, the increase in self-weight, and the efficiency of the gravitropic reaction. A biomechanical model was used to separate these contributions. Results showed that (1) gravitropic movements were based on a common mechanism associated to similar dynamic patterns, (2) clear differences in efficiency (defined as the change in curvature achieved during an elementary diameter increment for a given stem diameter) existed between species, (3) the equilibrium angle of the stem and the anatomical characters associated to the efficiency of the reaction also differed between species, (4) the differences in gravitropic reaction were related to the light requirements: heliophilic species, compared to more shade-tolerant species, had a larger efficiency and an equilibrium angle closer to vertical. This suggests that traits determining the gravitropic reaction are related to the strategy of light interception and may contribute to the differentiation of ecological strategies promoting the maintenance of biodiversity in tropical rain forests.

Published
2009

19. Mechanical stimuli regulate the allocation of biomass in trees: Demonstration with young[i] Prunus avium[/i] trees

Author

Boris Adam, Christian Dupraz, Stéphane Ploquin, Catherine Coutand, Gaëlle Jaouen, Laboratoire de Physique et Physiologie Intégratives de l'Arbre Fruitier et Forestier (PIAF), Institut National de la Recherche Agronomique (INRA)-Université Blaise Pascal - Clermont-Ferrand 2 (UBP), Fonctionnement et conduite des systèmes de culture tropicaux et méditerranéens (UMR SYSTEM), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Centre International de Hautes Etudes Agronomiques Méditerranéennes - Institut Agronomique Méditerranéen de Montpellier (CIHEAM-IAMM), Centre International de Hautes Études Agronomiques Méditerranéennes (CIHEAM)-Centre International de Hautes Études Agronomiques Méditerranéennes (CIHEAM)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Ecologie des forêts de Guyane (ECOFOG), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Université des Antilles et de la Guyane (UAG)-AgroParisTech-Centre National de la Recherche Scientifique (CNRS), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Centre International de Hautes Etudes Agronomiques Méditerranéennes - Institut Agronomique Méditerranéen de Montpellier (CIHEAM-IAMM), Centre International de Hautes Études Agronomiques Méditerranéennes (CIHEAM)-Centre International de Hautes Études Agronomiques Méditerranéennes (CIHEAM)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), and Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)

Subjects
0106 biological sciences, MERISIER, Plant Science, Root system, Biology, 01 natural sciences, Acclimatization, Staking, Trees, BIOMASS, 03 medical and health sciences, Prunus, Botany, BENDING, SHELTER, 030304 developmental biology, 0303 health sciences, Biomass (ecology), Original Articles, 15. Life on land, WIND, [SDV.BV.BOT]Life Sciences [q-bio]/Vegetal Biology/Botanics, Trunk, SHOOT/ROOT RATIO, Deciduous, Agronomy, Shoot, GROWTH, Stress, Mechanical, 010606 plant biology & botany, MECHANICAL STRESS
Abstract

Publication Inra prise en compte dans l'analyse bibliométrique des publications scientifiques mondiales sur les Fruits, les Légumes et la Pomme de terre. Période 2000-2012. http://prodinra.inra.fr/record/256699; Background and Aims Plastic tree-shelters are increasingly used to protect tree seedlings against browsing animals and herbicide drifts. The biomass allocation in young seedlings of deciduous trees is highly disturbed by common plastic tree-shelters, resulting in poor root systems and reduced diameter growth of the trunk. The shelters have been improved by creating chimney-effect ventilation with holes drilled at the bottom, resulting in stimulated trunk diameter growth, but the root deficit has remained unchanged. An experiment was set up to elucidate the mechanisms behind the poor root growth of sheltered Prunus avium trees. Methods Tree seedlings were grown either in natural windy conditions or in tree-shelters. Mechanical wind stimuli were suppressed in ten unsheltered trees by staking. Mechanical stimuli (bending) of the stem were applied in ten sheltered trees using an original mechanical device. Key Results Sheltered trees suffered from poor root growth, but sheltered bent trees largely recovered, showing that mechano-sensing is an important mechanism governing C allocation and the shoot-root balance. The use of a few artificial mechanical stimuli increased the biomass allocation towards the roots, as did natural wind sway. It was demonstrated that there was an acclimation of plants to the imposed strain. Conclusions This study suggests that if mechanical stimuli are used to control plant growth, they should be applied at low frequency in order to be most effective. The impact on the functional equilibrium hypothesis that is used in many tree growth models is discussed. The consequence of the lack of mechanical stimuli should be incorporated in tree growth models when applied to environments protected from the wind (e.g. greenhouses, dense forests).

Published
2008

20. Mechanical Stimuli Regulate the Allocation of Biomass in Trees: Demonstration with Young Prunus avium Trees.

Author

Catherine Coutand, Christian Dupraz, Gaëlle Jaouen, Stéphane Ploquin, and Boris Adam

Subjects
SWEET cherry, TREE seedlings, PLANT growth, PLANT development
Abstract

Background and Aims Plastic tree-shelters are increasingly used to protect tree seedlings against browsing animals and herbicide drifts. The biomass allocation in young seedlings of deciduous trees is highly disturbed by common plastic tree-shelters, resulting in poor root systems and reduced diameter growth of the trunk. The shelters have been improved by creating chimney-effect ventilation with holes drilled at the bottom, resulting in stimulated trunk diameter growth, but the root deficit has remained unchanged. An experiment was set up to elucidate the mechanisms behind the poor root growth of sheltered Prunus avium trees. Methods Tree seedlings were grown either in natural windy conditions or in tree-shelters. Mechanical wind stimuli were suppressed in ten unsheltered trees by staking. Mechanical stimuli (bending) of the stem were applied in ten sheltered trees using an original mechanical device. Key Results Sheltered trees suffered from poor root growth, but sheltered bent trees largely recovered, showing that mechano-sensing is an important mechanism governing C allocation and the shoot–root balance. The use of a few artificial mechanical stimuli increased the biomass allocation towards the roots, as did natural wind sway. It was demonstrated that there was an acclimation of plants to the imposed strain. Conclusions This study suggests that if mechanical stimuli are used to control plant growth, they should be applied at low frequency in order to be most effective. The impact on the functional equilibrium hypothesis that is used in many tree growth models is discussed. The consequence of the lack of mechanical stimuli should be incorporated in tree growth models when applied to environments protected from the wind (e.g. greenhouses, dense forests). [ABSTRACT FROM AUTHOR]

Published
2008
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