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Author Herault, B.; Ouallet, J.; Blanc, L.; Wagner, F.; Baraloto, C.
Title Growth responses of neotropical trees to logging gaps Type Journal Article
Year 2010 Publication Journal of Applied Ecology Abbreviated Journal J. Appl. Ecol.
Volume 47 Issue 4 Pages 821-831
Keywords canopy openings; functional traits; incidence function model; light partitioning; selective logging; tree growth rates; tropical rain forest
Abstract P>1. Modelling growth strategies among tropical trees is an important objective in predicting the response of tree dynamics to selective logging and in gaining insights into the ecological processes that structure tree communities in managed tropical forests. 2. We developed a disturbance index to model the effects of distance to and area of logging gaps on stem radial growth rates. This index was tested using census data of 43 neotropical tree species, representing a variety of life-history strategies and developmental stages, from a selectively logged forest at Paracou, French Guiana. Growth strategies were analyzed in light of two indicators: the inherent species growth rate (when disturbance index is null) and the species reaction (change in growth rate) to logging gaps. 3. Across species, the predicted inherent growth rates in unlogged forest ranged from 0 center dot 25 to 6 center dot 47 mm year-1, with an average growth of 2 center dot 29 mm year-1. Ontogenetic shifts in inherent growth rate were found in 26 of the 43 species. 4. Species growth response to logging gaps varied widely among species but was significantly positive for 27 species. The effect of ontogeny on growth response to logging was retained for 14 species, and species with inherent fast growth rate (5 mm year-1) responded less to logging gap disturbances than did species with slow inherent growth (1 mm year-1). 5. Functional traits explained 19-42% of the variation in the inherent growth rate and in species' response across all developmental stages. Whereas maximum diameters and seed mass were strong predictors of inherent growth rate, maximum height, wood density, mode of germination and stem architecture were additionally involved in tree growth response. 6. Synthesis and applications: This study provides a necessary framework for developing predictive post-logging growth models for the thousands of species comprising tropical forests and is sufficiently general to apply to a broad range of managed tropical forests.
Address [Herault, Bruno] Univ Antilles Guyane, UMR Ecol Forets Guyane, F-97387 Kourou, France, Email: bruno.herault@ecofog.gf
Corporate Author Thesis
Publisher WILEY-BLACKWELL PUBLISHING, INC Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN (down) 0021-8901 ISBN Medium
Area Expedition Conference
Notes ISI:000279405100012 Approved no
Call Number EcoFoG @ eric.marcon @ Serial 53
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Author Tindo, M.; Mbenoun Masse, P.S.; Kenne, M.; Mony, R.; Orivel, J.; Doumtsop Fotio, A.; Fotso Kuaté, A.; Djiéto-Lordon, C.; Fomena, A.; Estoup, A.; Dejean, A.; Foucaud, J.
Title Current distribution and population dynamics of the little fire ant supercolony in cameroon Type Journal Article
Year 2012 Publication Insectes Sociaux Abbreviated Journal Insectes Sociaux
Volume 59 Issue 2 Pages 175-182
Keywords Auropunctata; Dispersion; Invasive ants; Reproduction strategy; Unicoloniality; Wasmannia
Abstract The little fire ant, Wasmannia auropunctata, is native to Central America, but has been introduced into many parts of the world. We examined the current distribution of W. auropunctata in Cameroon, tested for aggression between workers from different parts of the country, and examined the genotypes of workers, queens, and males to evaluate the mating system. We found W. auropunctata at 36 sites in three provinces (Centre, East, and South). We found W. auropunctata only in human-disturbed habitats. Its spread appears to be primarily human mediated. Aggressive behaviour was almost non-existent between workers from different sites, indicating that there is only one supercolony in Cameroon. Our genetic analysis found that only one male/female pair of clones was introduced into Cameroon, probably from Gabon. No new male clonal lineage was identified, whereas new sexually derived female clonal lineages were noted. Apart from the genotype of the founding queen, which was well distributed but generally not dominant, a new clonal queen genotype emerged and was both omnipresent and dominant at most sites. These results may be useful in the development of management strategies. © International Union for the Study of Social Insects (IUSSI) 2011.
Address Laboratoire Evolution Genome Speciation, Centre National de la Recherche Scientifique, Avenue de la Terrasse, F 91198 Gif sur Yvette, France
Corporate Author Thesis
Publisher Place of Publication Editor
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Series Editor Series Title Abbreviated Series Title
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ISSN (down) 00201812 (Issn) ISBN Medium
Area Expedition Conference
Notes Export Date: 24 April 2012; Source: Scopus; Coden: Insoa; doi: 10.1007/s00040-011-0202-x; Language of Original Document: English; Correspondence Address: Tindo, M.; Département de Biologie des Organismes Animaux, Faculté des Sciences, Université de Douala, BP 24157 Douala, Cameroon; email: tindodouala@yahoo.com Approved no
Call Number EcoFoG @ webmaster @ Serial 392
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Author Lebrini, M.; Mbomekallé, I.M.; Dolbecq, A.; Marrot, J.; Berthet, P.; Ntienoue, J.; Sécheresse, F.; Vigneron, J.; Etcheberry, A.
Title Manganese(III)-containing wells-dawson sandwich-type polyoxometalates: Comparison with their manganese(II) counterparts Type Journal Article
Year 2011 Publication Inorganic Chemistry Abbreviated Journal Inorg. Chem.
Volume 50 Issue 14 Pages 6437-6448
Keywords
Abstract We present the synthesis and structural characterization, assessed by various techniques (FTIR, TGA, UV-vis, elemental analysis, single-crystal X-ray diffraction for three compounds, magnetic susceptibility, and electrochemistry) of five manganese-containing Wells-Dawson sandwich-type (WDST) complexes. The dimanganese(II)-containing complex, [Na2(H2O) 2MnII2(As2W15O 56)2]18- (1), was obtained by reaction of MnCl2 with 1 equiv of [As2W15O 56]12- in acetate medium (pH 4.7). Oxidation of 1 by Na2S2O8 in aqueous solution led to the dimanganese(III) complex [Na2(H2O)2Mn III2(As2W15O56) 2]16- (2), while its trimanganese(II) homologue, [Na(H2O)2MnII(H2O)Mn II2(As2W15O56) 2]17- (3), was obtained by addition of ca. 1 equiv of MnCl2 to a solution of 1 in 1 M NaCl. The trimanganese(III) and tetramanganese(III) counterparts, [MnIII(H2O)Mn III2(As2W15O56) 2]15- (4) and [MnIII2(H 2O)2MnIII2(As2W 15O56)2]12- (6), are, respectively, obtained by oxidation of aqueous solutions of 3 and [MnII2(H2O)2MnII2(As 2W15O56)2]16- (5) by Na2S2O8. Single-crystal X-ray analyses were carried out on 2, 3, and 4. BVS calculations and XPS confirmed that the oxidation state of Mn centers is +II for complexes 1, 3, and 5 and +III for 2, 4, and 6. A complete comparative electrochemical study was carried out on the six compounds cited above, and it was possible to observe the distinct redox steps MnIV/III and MnIII/II. Magnetization measurements, as a function of temperature, confirm the presence of antiferromagnetic interactions between the Mn ions in these compounds in all cases with the exception of compound 2. © 2011 American Chemical Society.
Address Laboratoire de Physico-Chimie de L'Etat Solide, ICMMO, Université Paris-Sud, Bâtiment 410, 91405 Orsay Cedex, France
Corporate Author Thesis
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Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN (down) 00201669 (Issn) ISBN Medium
Area Expedition Conference
Notes Export Date: 21 October 2011; Source: Scopus; Coden: Inoca; doi: 10.1021/ic102237x; Language of Original Document: English; Correspondence Address: Mbomekallé, I.M.; Institut Lavoisier de Versailles, UMR 8180, CNRS Université de Versailles Saint-Quentin, 45 Avenue des Etats-Unis, 78035 Versailles Cedex, France; email: israel.mbomekalle@chimie.uvsq.fr Approved no
Call Number EcoFoG @ webmaster @ Serial 346
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Author Grangier, J.; Orivel, J.; Negrini, M.; Dejean, A.
Title Low intraspecific aggressiveness in two obligate plant-ant species Type Journal Article
Year 2008 Publication Insectes Sociaux Abbreviated Journal Insect. Soc.
Volume 55 Issue 3 Pages 238-240
Keywords aggressiveness; Allomerus; myrmecophytes; plant-ants; recognition ability
Abstract Little is known about the aggressiveness of plant-ants typically living in isolated trees nor about how that aggressiveness varies based on this isolation. Here, we examine intra- and interspecific aggressiveness between workers of two Allomerus species associated with two different myrmecophytes. In both cases, the level of intraspecific aggressiveness is very low whatever the distance separating the tested nests, while interspecific conflicts are always violent. Similar patterns of aggressiveness have been reported in various ant species, but the strictly arboreal life of Allomerus ants associated with the isolation of their adult colonies highlight different ecological conditions that might explain the lack of aggressiveness between conspecifics.
Address [Grangier, J.; Orivel, J.; Negrini, M.; Dejean, A.] Univ Toulouse 3, CNRS, UMR 5174, Lab Evolut & Diversite Biol, F-31062 Toulouse 9, France, Email: grangier@cict.fr
Corporate Author Thesis
Publisher BIRKHAUSER VERLAG AG Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN (down) 0020-1812 ISBN Medium
Area Expedition Conference
Notes ISI:000258959300004 Approved no
Call Number EcoFoG @ eric.marcon @ Serial 208
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Author Dezerald, O.; Talaga, S.; Leroy, C.; Carrias, J.-F.; Corbara, B.; Dejean, A.; Céréghino, R.
Title Environmental determinants of macroinvertebrate diversity in small water bodies: Insights from tank-bromeliads Type Journal Article
Year 2014 Publication Hydrobiologia Abbreviated Journal Hydrobiologia
Volume 723 Issue 1 Pages 77-86
Keywords Freshwater biodiversity; Linear mixed effect modelling; Microcosms; Phytotelmata; Ponds
Abstract The interlocking leaves of tank-forming bromeliads (Bromeliaceae) collect rainwater and detritus, thus creating a freshwater habitat for specialized organisms. Their abundance and the possibility of quantifying communities with accuracy give us unparalleled insight into how changes in local to regional environments influence community diversity in small water bodies. We sampled 365 bromeliads (365 invertebrate communities) along a southeastern to northwestern range in French Guiana. Geographic locality determined the species pool for bromeliad invertebrates, and local environments determined the abundance patterns through the selection of traits that are best adapted to the bromeliad habitats. Patterns in community structure mostly emerged from patterns of predator species occurrence and abundance across local-regional environments, while the set of detritivores remained constant. Water volume had a strong positive correlation with invertebrate diversity, making it a biologically relevant measure of the pools' carrying capacity. The significant effects of incoming detritus and incident light show that changes in local environments (e.g., the conversion of forest to cropping systems) strongly influence freshwater communities. Because changes in local environments do not affect detritivores and predators equally, one may expect functional shifts as sets of invertebrates with particular traits are replaced or complemented by other sets with different traits. © 2013 Springer Science+Business Media Dordrecht.
Address CNRS, EcoLab (UMR-CNRS 5245), 118 Route de Narbonne, 31062 Toulouse, France
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN (down) 00188158 (Issn) ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number EcoFoG @ webmaster @ Serial 517
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Author Céréghino, R.; Corbara, B.; Leroy, C.; Carrias, J.-F.
Title Ecological determinants of community structure across the trophic levels of freshwater food webs: a test using bromeliad phytotelmata Type Journal Article
Year 2020 Publication Hydrobiologia Abbreviated Journal Hydrobiologia
Volume 847 Issue 2 Pages 391-402
Keywords Environmental filtering; Functional group; Neotropical; Niche; Trophic interactions; alga; assembly rule; bacterium; community structure; ecological modeling; environmental conditions; food web; freshwater ecosystem; functional group; Neotropic Ecozone; niche; protozoan; taxonomy; trophic interaction; trophic level; algae; Invertebrata; Protozoa
Abstract Understanding the relative importance of habitat and biotic drivers on community assembly across food web components is an important step towards predicting the consequences of environmental changes. Because documenting entire food webs is often impractical, this question has been only partially investigated. Here, we partitioned variation in species assemblages of the major components of tank bromeliad food webs (bacteria, algae, protozoans, detritivorous and predatory invertebrates) into habitat and biotic determinants and examined the influence of habitat variables and predator or prey abundance on all taxonomic assemblages. Ecological determinism of assemblage structure ranged from weak in bacteria (< 10% of the explained variance) to strong in predatory invertebrates (90%). Habitat features and canopy openness significantly influenced species assemblages; however, prey or predator density had far and away the most significant structuring effects. If biotic forces are at least as important as the abiotic forces while the importance of stochasticity declines towards upper trophic levels, then trophic levels could respond differently to natural or anthropogenic disturbance and to shifts in species distributions. The effects of such differential responses on food web reconfiguration, however, remain to be elucidated. © 2019, Springer Nature Switzerland AG.
Address UMR EcoFoG (AgroParisTech, CIRAD, CNRS, INRA, Université de Guyane, Université des Antilles), Kourou, 97310, France
Corporate Author Thesis
Publisher Springer Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN (down) 00188158 (Issn) ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number EcoFoG @ webmaster @ Serial 996
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Author Bourreau, D.; Aimene, Y.; Beauchene, J.; Thibaut, B.
Title Feasibility of glued laminated timber beams with tropical hardwoods Type Journal Article
Year 2013 Publication European Journal of Wood and Wood Products Abbreviated Journal Eur. J. Wood Wood Prod.
Volume 71 Issue 5 Pages 653-662
Keywords
Abstract A feasibility study of glulam was carried out in French Guiana using local wood species. The aim was to determine gluing parameters affording satisfactory behaviour to manufactured glulam in a tropical climate. Three abundant wood species, with special properties, were selected for the study and resorcinol-phenol-formaldehyde resin was used for bonding. Three industrial parameters were considered: adhesive spread rate, closed assembly time and gluing pressure. Delamination and shearing tests were carried out in accordance with European Standards. The tests revealed the influence of wood properties and manufacturing parameters on joint resistance. In fact, the results showed that specific gravity and the shrinkage coefficient greatly influenced the gluing step. Indeed, wood with a medium specific gravity needed more adhesive and more pressure than wood with a high specific gravity. In addition, planing and lamella thickness were found to affect glue joint resistance. © 2013 Springer-Verlag Berlin Heidelberg.
Address CNRS-LMGC Université de Montpellier2, 34095 Montpellier, France
Corporate Author Thesis
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ISSN (down) 00183768 (Issn) ISBN Medium
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Notes Export Date: 30 August 2013; Source: Scopus; doi: 10.1007/s00107-013-0721-4; Language of Original Document: English; Correspondence Address: Bourreau, D.; UAG-UMR Ecofog, Pôle Universitaire Guyanais, 97337 Cayenne cedex, French Guiana; email: dbourreau@nancy.inra.fr Approved no
Call Number EcoFoG @ webmaster @ Serial 497
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Author Latouche-Hallé, C.; Ramboer, A.; Bandou, E.; Caron, H.; Kremer, A.
Title Nuclear and chloroplast genetic structure indicate fine-scale spatial dynamics in a neotropical tree population Type Journal Article
Year 2003 Publication Heredity Abbreviated Journal Heredity
Volume 91 Issue 2 Pages 181-190
Keywords Dicorynia guianensis; Gene flow; Genetic differentiation; Microsatellites; Spatial analysis; Tropical tree; gene flow; genetic structure; population genetics; spatial analysis; tree; tropical forest; Cell Nucleus; Chloroplasts; Cohort Studies; DNA, Plant; French Guiana; Genetic Markers; Pollen; Population Dynamics; Seeds; Trees; Variation (Genetics); French Guiana; Dicorynia guianensis; Embryophyta
Abstract Dicorynia guianensis is a canopy tree, endemic to the tropical rain forest of French Guiana. We compared generational and spatial genetic structure for maternally and biparentally inherited markers in two cohorts (adult and seedling) in order to infer processes shaping the distribution of genetic diversity. The study was conducted on a 40 ha study plot located at Paracou near Kourou, where 172 adults trees and 375 saplings were sampled. Aggregation of trees was therefore suggested at different distances, ranging from 100 to 400 m. There was a strong link between demographic and genetic spatial structures at small distances (less than 100 m) that is likely to be the consequence of restricted seed dispersal. Genetic differentiation was more pronounced between spatial aggregates than between cohorts. Despite the spatial differentiation, the species was able to maintain high levels of diversity for maternal genomes, suggesting rapid turnover of aggregates. Spatial autocorrelation was larger for chloroplast than nuclear markers indicating a strong asymmetry between pollen and seed flow. Fixation indices indicated a lower heterozygote deficiency for the adults, maybe because of gradual elimination of selfed trees. Genetic relatedness at lower distances was higher in adult trees than in saplings, as a result of generation overlapping in the adult cohort. Overall, our results confirm earlier biological knowledge about the dispersion mechanisms of the species, and lead to an enhanced role of spatial processes in the dynamics of genetic diversity of D. guianensis.
Address INRA Lab. Genet. Arbres Forestiers, BP45, 33611 Gazinet Cedex, France
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ISSN (down) 0018067x (Issn) ISBN Medium
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Notes Cited By (since 1996): 34; Export Date: 22 October 2011; Source: Scopus; Coden: Hdtya; doi: 10.1038/sj.hdy.6800296; PubMed ID: 12886285; Language of Original Document: English; Correspondence Address: Caron, H.; INRA Lab. Genet. Arbres Forestiers, BP45, 33611 Gazinet Cedex, France; email: caron@pierroton.inra.fr; Chemicals/CAS: DNA, Plant; Genetic Markers Approved no
Call Number EcoFoG @ webmaster @ Serial 358
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Author Campillo, F.; Rossi, V.
Title Convolution Particle Filter for Parameter Estimation in General State-Space Models Type Journal Article
Year 2009 Publication IEEE Transactions on Aerospace and Electronic Systems Abbreviated Journal IEEE Trans. Aerosp. Electron. Syst.
Volume 45 Issue 3 Pages 1063-1072
Keywords
Abstract The state-space modeling of partially observed dynamical systems generally requires estimates of unknown parameters. The dynamic state vector together with the static parameter vector can be considered as an augmented state vector. Classical filtering methods, such as the extended Kalman filter (EKF) and the bootstrap particle filter (PF), fail to estimate the augmented state vector. For these classical filters to handle the augmented state vector, a dynamic noise term should be artificially added to the parameter components or to the deterministic component of the dynamical system. However, this approach degrades the estimation performance of the filters. We propose a variant of the PF based on convolution kernel approximation techniques. This approach is tested on a simulated case study.
Address
Corporate Author Thesis
Publisher IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
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ISSN (down) 0018-9251 ISBN Medium
Area Expedition Conference
Notes ISI:000270225500017 Approved no
Call Number EcoFoG @ eric.marcon @ Serial 194
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Author Royer, M.; Stien, D.; Beauchene, J.; Herbette, G.; McLean, J.P.; Thibaut, A.; Thibaut, B.
Title Extractives of the tropical wood wallaba (Eperua falcata Aubl.) as natural anti-swelling agents Type Journal Article
Year 2010 Publication Holzforschung Abbreviated Journal Holzforschung
Volume 64 Issue 2 Pages 211-215
Keywords
Abstract Wallaba (Eperua falcata) is a tropical wood that is known to have naturally high moisture related dimensional stability. Samples of wallaba heartwood were subjected to differential solvent extraction. Wood pieces that were extracted with methanol showed significantly greater swelling following rehydration from oven dry to 96% relative humidity than non- extracted samples and samples extracted with other solvents. Methanol soluble wallaba heartwood extract was purified by HPLC and the compounds present were characterized by NMR spectroscopy. The structure of 13 compounds in methanol extract was identified. The relative proportion of polar compounds in methanol extract was found to be high. The compounds identified are proposed to bind to the polymeric cell wall by means of multiple hydrogen bonds restricting the association of water and therefore act as natural anti-swelling agents.
Address
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ISSN (down) 0018-3830 ISBN Medium
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Notes WOS:000274423900010 Approved no
Call Number EcoFoG @ webmaster @ Serial 307
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