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Author Freycon, V.; Krencker, M.; Schwartz, D.; Nasi, R.; Bonal, D. openurl 
  Title The impact of climate changes during the Holocene on vegetation in northern French Guiana Type Journal Article
  Year 2010 Publication Quaternary Research Abbreviated Journal Quat. Res.  
  Volume (down) 73 Issue 2 Pages 220-225  
  Keywords Holocene; Vegetation change; French Guiana; Carbon isotope composition; Soil organic matter  
  Abstract The impact of climatic changes that occurred during the last glacial maximum and the Holocene on vegetation changes in the Amazon Basin and the Guiana Shield are still widely debated. The aim of our study was to investigate whether major changes in vegetation (i.e. transitions between rainforests and C-4 savannas) occurred in northern French Guiana during the Holocene. We measured variations in the delta C-13 of soil organic matter at eight sites now occupied by forest or savannah. The forest sites were selected to cover two regions (forest refugia and peneplains) which are thought to have experienced different intensities of disturbance during the latest Pleistocene and the Holocene. We found that none of the forest sites underwent major disturbances during the Holocene, i.e. they were not replaced by C-4 savannahs or C-4 forest savannahs for long periods. Our results thus suggest that tropical rainforests in northern French Guiana were resilient to drier climatic conditions during the Holocene. Nevertheless, geographical and vertical variations in the C-13 of SOM were compatible with minor changes in vegetation, variations in soil processes or in soil physical properties. (C) 2009 University of Washington. Published by Elsevier Inc. All rights reserved.  
  Address [Freycon, Vincent] CIRAD, UR Dynam Forestiere, F-34398 Montpellier 5, France, Email: vincent.freycon@cirad.fr  
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  Publisher ACADEMIC PRESS INC ELSEVIER SCIENCE Place of Publication Editor  
  Language Summary Language Original Title  
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  Series Volume Series Issue Edition  
  ISSN 0033-5894 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000275246700007 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 66  
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Author Cabanillas, B.J.; Le Lamer, A.C.; Castillo, D.; Arevalo, J.; Rojas, R.; Odonne, G.; Bourdy, G.; Moukarzel, B.; Sauvain, M.; Fabre, N. openurl 
  Title Caffeic Acid Esters and Lignans from Piper sanguineispicum Type Journal Article
  Year 2010 Publication Journal of Natural Products Abbreviated Journal J. Nat. Prod.  
  Volume (down) 73 Issue 11 Pages 1884-1890  
  Keywords  
  Abstract Three new caffeic acid esters (1-3), four new lignans (4-7), and the known compounds (7'S)-parabenzlactone (8), dihydrocubebin (9), and justiflorinol (10) have been isolated from leaves of Piper sanguineispicum. Their structures were determined by spectroscopic methods, including 1D and 2D NMR, HRCIMS, CD experiments, and chemical methods. Compounds 1-10 were assessed for their antileishmanial potential against axenic amastigote forms of Leishmania amazonensis. Caffeic acid esters 1 and 3 exhibited the best antileishmanial activity (IC50 2.0 and 1.8 μM, respectively) with moderate cytotoxicity on murine macrophages.  
  Address [Cabanillas, Billy Joel; Le Lamer, Anne-Cecile; Odonne, Guillaume; Bourdy, Genevieve; Moukarzel, Beatrice; Sauvain, Michel; Fabre, Nicolas] Univ Toulouse, UPS, UMR 152, Lab Pharmacochim Subst Nat & Pharmacophores Redox, F-31062 Toulouse 9, France, Email: michel.sauvain@ird.fr  
  Corporate Author Thesis  
  Publisher AMER CHEMICAL SOC Place of Publication Editor  
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  Series Volume Series Issue Edition  
  ISSN 0163-3864 ISBN Medium  
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  Notes ISI:000284559100024 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 74  
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Author Scotti, I.; González-Martínez, S.C.; Budde, K.B.; Lalague, H. url  openurl
  Title Fifty years of genetic studies: what to make of the large amounts of variation found within populations? Type Journal Article
  Year 2016 Publication Annals of Forest Science Abbreviated Journal Annals of Forest Science  
  Volume (down) 73 Issue 1 Pages 69-75  
  Keywords Intra-specific variation; Microgeography; Natural selection; Population genomics  
  Abstract  
  Address INRA, UMR745 Ecologie des Forêts de Guyane, Campus Agronomique, Kourou, French Guiana  
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  Notes Export Date: 7 March 2016 Approved no  
  Call Number EcoFoG @ webmaster @ Serial 667  
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Author Thibaut, B.; Denaud, L.; Collet, R.; Marchal, R.; Beauchene, J.; Mothe, F.; Méausoone, P.-J.; Martin, P.; Larricq, P.; Eyma, F. url  openurl
  Title Wood machining with a focus on French research in the last 50 years Type Journal Article
  Year 2016 Publication Annals of Forest Science Abbreviated Journal Annals of Forest Science  
  Volume (down) 73 Issue 1 Pages 163-184  
  Keywords Primary conversion; Secondary processing; Surface quality; Tool wear  
  Abstract Key message: Wood machining is compulsory both for timber separation and the surfacing of wooden objects. The anisotropy, cellular nature and multi-scale level organisation of wood make its cutting complicated to study. During the last 50 years, most of the wood machining subjects were covered by French teams. Context: Woodcutting is a very old technology but scientific research is scarce on the subject. In the last 50 years, much work on basic mechanisms as well as on industrial processes has been done in France. Aims: The specific nature of wood introduces strong differences between wood and metal cutting processes. The paper focuses on French teams’ contributions. Results: The basic aspects of the tool–material interaction for different basic modes in woodcutting are highlighted. In primary conversion such as sawing, veneer cutting or green wood chipping, huge progress comes from automation and the possibility of linking the process to log and product quality through new sensors. In secondary processing, much has been done on the links between the cutting process, surface qualification and the properties of these surfaces for further processing, such as gluing or coating. Tool wear depends on the cutting process, timber quality and species. Trade-offs are required in tool technology and coating technologies may improve tool life. Conclusion: A large amount of knowledge and innovation has come from 50 years of worldwide research effort, with France being particularly active in this period. The transfer of skills from metals cutting industry was often a key, but much is needed to move closer to both metal cutting sector and woodcutting skills among craftsmen. © 2015, INRA and Springer-Verlag France.  
  Address ICA, Université Paul Sabatier Toulouse III, Toulouse, France  
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  Notes Export Date: 7 March 2016 Approved no  
  Call Number EcoFoG @ webmaster @ Serial 668  
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Author Bonal, D.; Burban, B.; Stahl, C.; Wagner, F.; Herault, B. url  openurl
  Title The response of tropical rainforests to drought—lessons from recent research and future prospects Type Journal Article
  Year 2016 Publication Annals of Forest Science Abbreviated Journal Annals of Forest Science  
  Volume (down) 73 Issue 1 Pages 27-44  
  Keywords Carbon; Climate; Drought; Global change; Growth; Mortality; Soil; Tropical; Water  
  Abstract Key message: We review the recent findings on the influence of drought on tree mortality, growth or ecosystem functioning in tropical rainforests. Drought plays a major role in shaping tropical rainforests and the response mechanisms are highly diverse and complex. The numerous gaps identified here require the international scientific community to combine efforts in order to conduct comprehensive studies in tropical rainforests on the three continents. These results are essential to simulate the future of these ecosystems under diverse climate scenarios and to predict the future of the global earth carbon balance. Context: Tropical rainforest ecosystems are characterized by high annual rainfall. Nevertheless, rainfall regularly fluctuates during the year and seasonal soil droughts do occur. Over the past decades, a number of extreme droughts have hit tropical rainforests, not only in Amazonia but also in Asia and Africa. The influence of drought events on tree mortality and growth or on ecosystem functioning (carbon and water fluxes) in tropical rainforest ecosystems has been studied intensively, but the response mechanisms are complex. Aims: Herein, we review the recent findings related to the response of tropical forest ecosystems to seasonal and extreme droughts and the current knowledge about the future of these ecosystems. Results: This review emphasizes the progress made over recent years and the importance of the studies conducted under extreme drought conditions or in through-fall exclusion experiments in understanding the response of these ecosystems. It also points to the great diversity and complexity of the response of tropical rainforest ecosystems to drought. Conclusion: The numerous gaps identified here require the international scientific community to combine efforts in order to conduct comprehensive studies in tropical forest regions. These results are essential to simulate the future of these ecosystems under diverse climate scenarios and to predict the future of the global earth carbon balance. © 2015, INRA and Springer-Verlag France.  
  Address National Institute for Space Research (INPE), São José dos Campos, SP, Brazil  
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  Notes Export Date: 7 March 2016 Approved no  
  Call Number EcoFoG @ webmaster @ Serial 669  
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Author Schimann, H.; Bach, C.; Lengelle, J.; Louisanna, E.; Barantal, S.; Murat, C.; Buée, M. url  doi
openurl 
  Title Diversity and Structure of Fungal Communities in Neotropical Rainforest Soils: The Effect of Host Recurrence Type Journal Article
  Year 2017 Publication Microbial Ecology Abbreviated Journal Microbial Ecology  
  Volume (down) 73 Issue 2 Pages 310-320  
  Keywords Amazonian forest; Fungal communities; Host recurrence; Litter; Second-generation sequencing; Soil  
  Abstract The patterns of the distribution of fungal species and their potential interactions with trees remain understudied in Neotropical rainforests, which harbor more than 16,000 tree species, mostly dominated by endomycorrhizal trees. Our hypothesis was that tree species shape the non-mycorrhizal fungal assemblages in soil and litter and that the diversity of fungal communities in these two compartments is partly dependent on the coverage of trees in the Neotropical rainforest. In French Guiana, a long-term plantation and a natural forest were selected to test this hypothesis. Fungal ITS1 regions were sequenced from soil and litter samples from within the vicinity of tree species. A broad range of fungal taxa was found, with 42 orders and 14 classes. Significant spatial heterogeneity in the fungal communities was found without strong variation in the species richness and evenness among the tree plots. However, tree species shaped the fungal assemblages in the soil and litter, explaining up to 18 % of the variation among the communities in the natural forest. These results demonstrate that vegetation cover has an important effect on the structure of fungal assemblages inhabiting the soil and litter in Amazonian forests, illustrating the relative impact of deterministic processes on fungal community structures in these highly diverse ecosystems. © 2016, Springer Science+Business Media New York.  
  Address Equipe Environnement et Microbiologie, Institut Pluridisciplinaire de Recherche en Environnement et Matériaux, Université de Pau et Pays de l’Adour, Pau, France  
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  Notes Export Date: 19 February 2017 Approved no  
  Call Number EcoFoG @ webmaster @ Serial 734  
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Author Michalet, S.; Rohr, J.; Warshan, D.; Bardon, C.; Roggy, J.-C.; Domenach, A.-M.; Czarnes, S.; Pommier, T.; Combourieu, B.; Guillaumaud, N.; Bellvert, F.; Comte, G.; Poly, F. url  openurl
  Title Phytochemical analysis of mature tree root exudates in situ and their role in shaping soil microbial communities in relation to tree N-acquisition strategy Type Journal Article
  Year 2013 Publication Plant Physiology and Biochemistry Abbreviated Journal Plant Physiol. Biochem.  
  Volume (down) 72 Issue Pages 169-177  
  Keywords Chemical ecology; Denitrification; Eperua falcata; Metabolic profiling; Mycorrhizae; Plant-microbes interactions; Root exudates  
  Abstract Eperua falcata (Aublet), a late-successional species in tropical rainforest and one of the most abundant tree in French Guiana, has developed an original strategy concerning N-acquisition by largely preferring nitrate, rather than ammonium (H. Schimann, S. Ponton, S. Hättenschwiler, B. Ferry, R. Lensi, A.M. Domenach, J.C. Roggy, Differing nitrogen use strategies of two tropical rainforest tree species in French Guiana: evidence from 15N natural abundance and microbial activities, Soil Biol. Biochem. 40 (2008) 487-494). Given the preference of this species for nitrate, we hypothesized that root exudates would promote nitrate availability by (a) enhancing nitrate production by stimulating ammonium oxidation or (b) minimizing nitrate losses by inhibiting denitrification.Root exudates were collected in situ in monospecific planted plots. The phytochemical analysis of these exudates and of several of their corresponding root extracts was achieved using UHPLC/DAD/ESI-QTOF and allowed the identification of diverse secondary metabolites belonging to the flavonoid family.Our results show that (i) the distinct exudation patterns observed are related to distinct root morphologies, and this was associated with a shift in the root flavonoid content, (ii) a root extract representative of the diverse compounds detected in roots showed a significant and selective metabolic inhibition of isolated denitrifiers invitro, and (iii) in soil plots the abundance of nirK-type denitrifiers was negatively affected in rhizosphere soil compared to bulk. Altogether this led us to formulate hypothesis concerning the ecological role of the identified compounds in relation to N-acquisition strategy of this species. © 2013 Elsevier Masson SAS.  
  Address SOLICAZ, c/o Guyane Technopole 16 bis rue du 14 Juillet, 97300 Cayenne, French Guiana  
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  ISSN 09819428 (Issn) ISBN Medium  
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  Notes Export Date: 15 November 2013; Source: Scopus; Coden: Ppbie; doi: 10.1016/j.plaphy.2013.05.003; Language of Original Document: English; Correspondence Address: Michalet, S.; Université Lyon1, CNRS, UMR5557, INRA, USC1364, Ecologie Microbienne, Centre d'Etude des Substances Naturelles, Pavillon Nétien, ISPB, 8 Avenue Rockefeller, 69373 Lyon cedex, France; email: sergemichalet@yahoo.fr Approved no  
  Call Number EcoFoG @ webmaster @ Serial 509  
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Author Leclerc, T.; Vimal, R.; Troispoux, V.; Périgon, S.; Scotti, I. url  openurl
  Title Life after disturbance (I): changes in the spatial genetic structure of Jacaranda copaia (Aubl.) D. Don (Bignonianceae) after logging in an intensively studied plot in French Guiana Type Journal Article
  Year 2015 Publication Annals of Forest Science Abbreviated Journal Annals of Forest Science  
  Volume (down) 72 Issue 5 Pages 509-516  
  Keywords Amazon; Bayesian clustering; Demogenetics; Guiana shield; Parentage analysis; Regeneration; Spatial genetic structure; Tropical rainforest  
  Abstract Key message: Forest disturbance affects the within-population distribution of genetic diversity, but not its overall levels, in a tropical pioneer tree species. In particular, clumps of related saplings with impoverished diversity are found in canopy gaps but not under forest cover. Context: Forest disturbances can have long-term consequences on the genetic structure of tree populations, because they can alter the demographic properties of the regeneration process and favour some subpopulations/genotypes, both by stochastic processes and by selection. Intermediate disturbances tend to favour species diversity, at least in highly diverse communities, but their effect on intra-specific diversity is unknown. Aims: In this study, we have looked at the genetic consequences of forest disturbance in a stand of the long-lived Neotropical pioneer species, Jacaranda copaia. Methods: The study site was experimentally logged in 1984, and the canopy gaps generated by the logging were mapped. Seedlings of J. copaia colonised the gaps, as expected, at a higher density than in the surrounding forest. In 2006, we exhaustively sampled all saplings and adult trees available in a 25-ha area. The samples were genotyped at nine microsatellite loci, and the distribution of genetic diversity was inspected by analyses of spatial autocorrelation, automated Bayesian assignment and comparisons of diversity between cohorts by bootstrap (RaBoT). Results: Spatial autocorrelation was found to extend farther in post-disturbance saplings than in the undisturbed population (100 m and beyond versus less than 50 m), and divergent clumps (F<inf>ST</inf> = 0.05) of related genotypes were found; genetic diversity was found to be impoverished in each clump relative to the global population at about half of the loci. Conclusion: Overall, our results suggest that forest disturbance has changed the patterns of distribution of genetic diversity, with potential consequences on long-term population viability. © 2015, INRA and Springer-Verlag France.  
  Address INRA, URFM « Ecologie des Forêts Méditerranéennes », Domaine de Saint-Paul, Avignon, France  
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  Notes Export Date: 16 July 2015 Approved no  
  Call Number EcoFoG @ webmaster @ Serial 611  
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Author Scotti, I.; Montaigne, W.; Cseke, K.; Traissac, S. url  openurl
  Title Life after disturbance (II): the intermediate disturbance hypothesis explains genetic variation in forest gaps dominated by Virola michelii Heckel (Myristicaceae) Type Journal Article
  Year 2015 Publication Annals of Forest Science Abbreviated Journal Annals of Forest Science  
  Volume (down) 72 Issue 8 Pages 1035-1042  
  Keywords Amazon; Bayesian clustering; Demogenetics; Guiana shield; Parentage analysis; Regeneration; Spatial genetic structure; Tropical rainforest  
  Abstract Key message: Genetic diversity appears to be unaffected by disturbance in a stand of the light-demanding Neotropical treeV. michelii. Although spatial genetic structure is modified in post-disturbance cohorts, mixing of seeds from different mother trees in canopy gaps appears to efficiently maintain genetic admixture. Context: The interplay between genetic and demographic processes has major consequences on population viability. Population size affects demographic trends, while genetic diversity insures viability by reducing risks of inbreeding depression and by maintaining adaptive potential. Yet, the consequences of increases in census size (as opposed to effective size) on genetic diversity of forest populations are poorly known. Aims: We have studied the structure of genetic diversity in populations of saplings of the light-responsive tree, Virola michelii (Myristicaceae, the nutmeg family), in two plots having undergone different levels of canopy-gap opening disturbance. This allowed us to test the “intermediate disturbance” hypothesis, which generally applies to species diversity, at the intra-specific scale. Methods: Levels and distribution of genetic diversity were compared between plots and between life stages. Sapling parentage was analysed to infer each adult tree’s contribution to regeneration. Results: Genetic diversity was higher, and spatial genetic structure was stronger in the post-disturbance than in the control seedling population. Parentage analysis suggested that a limited number of parents contributed to most of the regeneration, but that efficient mixing of their progeny may have enhanced the diversity of saplings occupying canopy gaps. Conclusion: A mixture of demo-genetic processes may contribute to maintain genetic diversity in spite of, or possibly due to, ecosystem disturbance in V. michelii. © 2015, INRA and Springer-Verlag France.  
  Address Solicaz, Guyane Technopôle, 16 bis Rue du 14 Juillet, Cayenne, French Guiana  
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  Notes Export Date: 14 December 2015 Approved no  
  Call Number EcoFoG @ webmaster @ Serial 642  
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Author Levionnois, Sébastien ; Salmon, Camille ; Alméras, Tancrède ; Clair, Bruno ; Ziegler, Camille ; Coste, Sabrina ; Stahl, Clement ; Gonzalez-Melo, Andrés ; Heinz, Christine ; Heuret, Patrick doi  openurl
  Title Anatomies, vascular architectures, and mechanics underlying the leaf size-stem size spectrum in 42 Neotropical tree species Type Journal Article
  Year 2021 Publication Journal of Experimental Botany Abbreviated Journal  
  Volume (down) 72 Issue 22 Pages 7957–7969  
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  Abstract The leaf size-stem size spectrum is one of the main dimensions of plant ecological strategies. Yet the anatomical, mechanical, and hydraulic implications of small vs. large shoots are still poorly understood. We investigated 42 tropical rainforest tree species in French Guiana, with a wide range of leaf areas at the shoot level. We quantified the scaling of hydraulic and mechanical constraints with shoot size estimated as the water potential difference ΔΨ and the bending angle ΔΦ, respectively. We investigated how anatomical tissue area, flexural stiffness and xylem vascular architecture affect such scaling by deviating (or not) from theoretical isometry with shoot size variation. Vessel diameter and conductive path length were found to be allometrically related to shoot size, thereby explaining the independence between ΔΨ and shoot size. Leaf mass per area, stem length, and the modulus of elasticity were allometrically related with shoot size, explaining the independence between ΔΦ and shoot size. Our study also shows that the maintenance of both water supply and mechanical stability across the shoot size range are not in conflict.  
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  Call Number EcoFoG @ webmaster @ Serial 1050  
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