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Author Leroy, C.; Gueroult, M.; Wahyuni, N.S.; Escoute, J.; Cereghino, R.; Sabatier, S.; Auclair, D. openurl 
  Title Morphogenetic trends in the morphological, optical and biochemical features of phyllodes in Acacia mangium Willd (Mimosaceae) Type Journal Article
  Year 2009 Publication Trees-Structure and Function Abbreviated Journal Trees-Struct. Funct.  
  Volume 23 Issue 1 Pages 37-49  
  Keywords Chlorophyll; Phyllode morphology; Phyllode anatomy; Nitrogen; Optical properties; Plant architecture  
  Abstract Endogenous variations in the annual growth of trees suggest that similar trends would occur in phyllodes. In comparison to leaves, the characteristics of phyllodes are less well known, hence this study examines the effects of architectural position and age of tree on the phyllodes of Acacia mangium. Phyllodes were investigated on 1-, 2-, and 3-year-old trees from three axis positions within the crown. We focused on the morphological, optical and biochemical traits of the phyllodes. The increase in phyllode area and lamina thickness is more pronounced in the older trees. Leaf mass area (LMA), stomatal density, nitrogen and chlorophyll content increase with tree age. The values of these characteristics decrease from the main stem to the lower branches for the older trees. Phyllode light absorptance increased with tree age whereas reflectance was higher for the upper position compared to the lower position within the crown. Carotenoid content and chlorophyll a/b ratio were higher for the younger phyllodes of younger trees. Increasing tree size induced modifications in the phyllode characteristics which are influenced by both morphogenetic and light gradients within the crown. This study demonstrated pronounced changes in terms of morphological and functional indicators of photosynthetic capacity in relation to phyllode position within the crown and to tree age. These morphogenetic effects on the phyllode characteristics should be taken into account in studies on phenotypic plasticity.  
  Address [Sabatier, Sylvie] CIRAD, UMR AMAP BotAnique & BioinforMat Architecture, F-34398 Montpellier 5, France, Email: sylvie-annabel.sabatier@cirad.fr  
  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 0931-1890 ISBN Medium  
  Area Expedition Conference  
  Notes (down) ISI:000262538700005 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 206  
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Author Jabiol, J.; Corbara, B.; Dejean, A.; Cereghino, R. openurl 
  Title Structure of aquatic insect communities in tank-bromeliads in a East-Amazonian rainforest in French Guiana Type Journal Article
  Year 2009 Publication Forest Ecology and Management Abbreviated Journal For. Ecol. Manage.  
  Volume 257 Issue 1 Pages 351-360  
  Keywords Bromeliaceae; Classification; Community structure; Insects; Microcosms; Neural networks; Nouragues; Phytotelmata; Species richness  
  Abstract Tank-bromeliads are discrete habitats which contain distinct aquatic communities, and which commonly occur in the neotropics. Because they span a broad range of ecological gradients in terms of habitat structure and amount of resources, researchers study the associations between the biodiversity of communities and these gradients in rainforests, where the very high species richness and densities within other continuous habitats makes it difficult to quantify animal communities. We analysed the diversity of aquatic insect communities in relation to different tank-bromeliad species in a primary rainforest (French Guiana) using artificial intelligence and complex optimization techniques to classify communities and model their determinants. First, the self-organizing map (neural network) was used to classify 158 bromeliads according to the quantitative structure of the insect communities. Catopsis berteroniana and Guzmania lingulata formed separate clusters of plants on the virtual map, while Vriesea splendens, Vriesea pleiosticha and Aechmea melinonii were grouped together in the remaining clusters. Some insect taxa occurred in all bromeliads, while other taxa were specific to a given species. Second, general linear modelling allowed us to specify the influence of the bromeliad species; water volume and volume of fine particulate organic matter inside of the tank; elevation above the ground; and sampling site on taxonomic richness and insect abundance. The number of taxa and individuals per plant increased with greater water volume, but the slope of the relationships depended on the bromeliad species. The significant influence of bromeliad species suggested that at similar water volumes different plant species had different taxon richness and insect abundance. Greater amounts of fine particulate organic matter were detrimental to community diversity in the tanks, probably because they decreased available space by clogging it and/or affected oxygen concentrations. The influence of tank-bromeliad species on the aquatic insect community was primarily related to their physical (and probably chemical) features rather than to species-specific associations sensu stricto. The classification of bromeliads with respect to animal species is likely to provide referential schemes for those biodiversity patterns to be expected under certain conditions, and may help to target model communities for subsequent experimental research. (C) 2008 Elsevier B,V. All rights reserved.  
  Address [Jabiol, J.; Cereghino, R.] Univ Toulouse 3, Ecolab, Lab Ecol Fonctionnelle, CNRS,UMR 5245, F-31062 Toulouse 9, France, Email: cereghin@cict.fr  
  Corporate Author Thesis  
  Publisher ELSEVIER SCIENCE BV Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0378-1127 ISBN Medium  
  Area Expedition Conference  
  Notes (down) ISI:000261856000038 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 124  
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Author Dejean, A.; Grangier, J.; Leroy, C.; Orivel, J. openurl 
  Title Predation and aggressiveness in host plant protection: a generalization using ants from the genus Azteca Type Journal Article
  Year 2009 Publication Naturwissenschaften Abbreviated Journal Naturwissenschaften  
  Volume 96 Issue 1 Pages 57-63  
  Keywords Aggressiveness; Ant-plant relationships; Biotic defence; Predation  
  Abstract In studying the ant genus Azteca, a Neotropical group of arboreal species, we aimed to determine the extent to which the ants use predation and/or aggressiveness to protect their host plants from defoliating insects. We compared a territorially dominant, carton-nester, Azteca chartifex, and three plant-ant species. Azteca alfari and Azteca ovaticeps are associated with the myrmecophyte Cecropia (Cecropiaceae) and their colonies shelter in its hollow branches; whereas Azteca bequaerti is associated with Tococa guianensis (Melastomataceae) and its colonies shelter in leaf pouches situated at the base of the laminas. Whereas A. bequaerti workers react to the vibrations transmitted by the lamina when an alien insect lands on a leaf making it unnecessary for them to patrol their plant, the workers of the three other species rather discover prey by contact. The workers of all four species use a predatory behaviour involving spread-eagling alien insects after recruiting nestmates at short range, and, in some cases, at long range. Because A. alfari and A. ovaticeps discard part of the insects they kill, we deduced that the workers' predatory behaviour and territorial aggressiveness combine in the biotic defence of their host tree.  
  Address [Dejean, Alain; Leroy, Celine] CNRS, UMR Ecol Forets Guyane 8172, F-97379 Kourou, France, Email: alain.dejean@wanadoo.fr  
  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 0028-1042 ISBN Medium  
  Area Expedition Conference  
  Notes (down) ISI:000261791000006 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 125  
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Author Amusant, N.; Fournier, M.; Beauchene, J. openurl 
  Title Colour and decay resistance and its relationships in Eperua grandiflora Type Journal Article
  Year 2008 Publication Annals of Forest Science Abbreviated Journal Ann. For. Sci.  
  Volume 65 Issue 8 Pages 806  
  Keywords natural durability; colour; decay resistance; variability; heartwood; tropical wood  
  Abstract Eperua grandiflora, which is widely distributed in the French Guiana forest region, shows high variability in decay resistance. Further information concerning this wood quality parameter is necessary, but standard testing methods are complex and time-consuming. We assessed the use of colorimetry to determine durability in heartwood samples from a range of trees. Eperua grandiflora colour parameters were measured using a CIELAB system, revealing that the tree effect was greater than the radial position and height effects. The wood samples were exposed to Coriolus versicolor and Antrodia sp. according to two European standards (En 350-1 and XP CEN TS 15083-1). Eperua grandiflora is more susceptible to brown rot. These two standards did not give the same durability classes. The high variation in natural durability was due to the tree effect. These two properties were found to be correlated and the assessment also distinguished the extreme durability classes but they are not sufficient to classify the class of durability of this species.  
  Address [Amusant, Nadine] CIRAD, PERSYT, UR Valorisat Bois Tropicaux, F-34538 Montpellier 5, France, Email: nadine.amusant@cirad.fr  
  Corporate Author Thesis  
  Publisher EDP SCIENCES S A Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1286-4560 ISBN Medium  
  Area Expedition Conference  
  Notes (down) ISI:000261431600006 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 127  
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Author Gibernau, M.; Orivel, J.; Dejean, A.; Delabie, J.; Barabe, D. openurl 
  Title Flowering as a key factor in ant-Philodendron interactions Type Journal Article
  Year 2008 Publication Journal of Tropical Ecology Abbreviated Journal J. Trop. Ecol.  
  Volume 24 Issue Pages 689-692  
  Keywords Araceae; domatia; habitat; nest site; non-specific association; Philodendron solimoesense; territoriality  
  Abstract  
  Address [Gibernau, Marc; Orivel, Jerome] Univ Toulouse 3, Lab Evolut & Divers Biol, UMR CNRS 5174, F-31062 Toulouse 9, France, Email: gibernau@cict.fr  
  Corporate Author Thesis  
  Publisher CAMBRIDGE UNIV PRESS Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0266-4674 ISBN Medium  
  Area Expedition Conference  
  Notes (down) ISI:000261254400012 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 128  
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Author Almeras, T. openurl 
  Title Mechanical analysis of the strains generated by water tension in plant stems. Part II: strains in wood and bark and apparent compliance Type Journal Article
  Year 2008 Publication Tree Physiology Abbreviated Journal Tree Physiol.  
  Volume 28 Issue 10 Pages 1513-1523  
  Keywords biomechanics; calibration; diurnal strains; mechanical model; multilayer cylinder; water potential  
  Abstract Tree steins shrink in diameter during the day and swell during the night in response to changes in water tension in the xylem. Stein shrinkage can easily be measured in a nondestructive way, to derive continuous information about tree water status. The relationship between the strain and the change in water tension can be evaluated by empirical calibrations, or can be related to the structure of the plant. A mechanical analysis was performed to make this relationship explicit. The stem is modeled as a cylinder made of multiple layers of tissues, including heartwood, sapwood, and inner and outer bark. The effect of changes in water tension on the apparent strain at the surface of a tissue is quantified as a function of parameters defining stem anatomy and the mechanical properties of the tissues. Various possible applications in the context of tree physiology are suggested.  
  Address INRA UMR Ecofog, Kourou 97379, French Guiana, Email: t_almeras@hotmail.com  
  Corporate Author Thesis  
  Publisher HERON PUBLISHING Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0829-318X ISBN Medium  
  Area Expedition Conference  
  Notes (down) ISI:000260027200009 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 129  
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Author Grangier, J.; Dejean, A.; Male, P.J.G.; Orivel, J. openurl 
  Title Indirect defense in a highly specific ant-plant mutualism Type Journal Article
  Year 2008 Publication Naturwissenschaften Abbreviated Journal Naturwissenschaften  
  Volume 95 Issue 10 Pages 909-916  
  Keywords Allomerus decemarticulatus; Hirtella physophora; indirect defense; myrmecophytes; optimal defense theory  
  Abstract Although associations between myrmecophytes and their plant ants are recognized as a particularly effective form of protective mutualism, their functioning remains incompletely understood. This field study examined the ant-plant Hirtella physophora and its obligate ant associate Allomerus decemarticulatus. We formulated two hypotheses on the highly specific nature of this association: (1) Ant presence should be correlated with a marked reduction in the amount of herbivory on the plant foliage; (2) ant activity should be consistent with the “optimal defense” theory predicting that the most vulnerable and valuable parts of the plant are the best defended. We validated the first hypothesis by demonstrating that for ant-excluded plants, expanding leaves, but also newly matured ones in the long term, suffered significantly more herbivore damage than ant-inhabited plants. We showed that A. decemarticulatus workers represent both constitutive and inducible defenses for their host, by patrolling its foliage and rapidly recruiting nestmates to foliar wounds. On examining how these activities change according to the leaves' developmental stage, we found that the number of patrolling ants dramatically decreased as the leaves matured, while leaf wounds induced ant recruitment regardless of the leaf's age. The resulting level of these indirect defenses was roughly proportional to leaf vulnerability and value during its development, thus validating our second hypothesis predicting optimal protection. This led us to discuss the factors influencing ant activity on the plant's surface. Our study emphasizes the importance of studying both the constitutive and inducible components of indirect defense when evaluating its efficacy and optimality.  
  Address [Grangier, Julien; Dejean, Alain; Male, Pierre-Jean G.; Orivel, Jerome] Univ Toulouse 3, Lab Evolut & Diversite Biol, CNRS, UMR 5174, F-31062 Toulouse 9, France, Email: grangier@cict.fr  
  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 0028-1042 ISBN Medium  
  Area Expedition Conference  
  Notes (down) ISI:000259737600002 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 207  
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Author McClure, M.; Chouteau, M.; Dejean, A. openurl 
  Title Territorial aggressiveness on the arboreal ant Azteca alfari by Camponotus blandus in French Guiana due to behavioural constraints Type Journal Article
  Year 2008 Publication Comptes Rendus Biologies Abbreviated Journal C. R. Biol.  
  Volume 331 Issue 9 Pages 663-667  
  Keywords Azteca alfari (Dolichoderinae); Camponotus blandus (Formicinae); foraging; rhythm of activity; territorial aggressiveness  
  Abstract This study reports new information on interactions between two sympatric ant species, the plant-ant Azteca alfari (Dolichoderinae) living in association with the myrmecophyte Cecropia obtusa (Cecropiaceae) and Camponotus blandus (Formicinae), a ground-nesting, arboreal-foraging species. Workers of A. alfari forage only on the foliage and the tipper parts of the trunk of their host Cecropia, while C. blandus nests in the ground but frequently forages and patrols pioneer tree foliage, including Cecropia. The activity pattern of A. alfari and the number of C. blandus on Cecropia obtusa was monitored hourly during a two-day period in a disturbed area in French Guiana. The maximum activity of C. blandus occurred between 8:30 and 12:30, at which time A. alfari had retreated within the domatia and were least present on the trunks. Even though aggressive confrontations were observed, C. blandus workers often initiate confrontations but do not prey on A. alfari nor exploit food bodies produced by Cecropia, the principal food source of A. alfari. Hence hostility appears to be the result of territoriality. Differences in their foraging rhythms are proposed as promoting resource and territory partitioning in this ant assemblage.  
  Address [McClure, Melanie] Concordia Univ, Dept Biol, Montreal, PQ H4B 1R6, Canada, Email: m_mcclur@alcor.concordia.ca  
  Corporate Author Thesis  
  Publisher ELSEVIER FRANCE-EDITIONS SCIENTIFIQUES MEDICALES ELSEVIER Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1631-0691 ISBN Medium  
  Area Expedition Conference  
  Notes (down) ISI:000259290200004 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 130  
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Author Grangier, J.; Orivel, J.; Negrini, M.; Dejean, A. openurl 
  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 0020-1812 ISBN Medium  
  Area Expedition Conference  
  Notes (down) ISI:000258959300004 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 208  
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Author Herault, B.; Bornet, A.; Tremolieres, M. openurl 
  Title Redundancy and niche differentiation among the European invasive Elodea species Type Journal Article
  Year 2008 Publication Biological Invasions Abbreviated Journal Biol. Invasions  
  Volume 10 Issue 7 Pages 1099-1107  
  Keywords biological traits; functional equivalence; invasivness; niche overlapping; waterweeds  
  Abstract Community ecologists implicitly assume redundancy when they aggregate species into functional groups. But there have been remarkably few empirical efforts to investigate the accuracy of this concept in situ. The concept of redundancy could be roughly split into two components: the ecological redundancy (similar response to environmental variations involving similar ecological processes) and the functional redundancy (similar biological trait combinations shaping similar functional processes). Both types of redundancy are tested among the 3 invasive European Elodeas. In 11 sites and during two successive years 2004-2005, the cover growth rate of each Elodea species was monthly recorded. To test ecological redundancy, cover growth rates were related to a large suite of environmental variables. To test functional redundancy, 13 biological traits involved in competitive relationships were measured each month. Firstly, the redundancy hypothesis looks problematic for Elodea ernstiae. Indeed, the later possess numerous biological traits involved in light competition and niche overlap with the other Elodeas is very low. Secondly, ecological and functional redundancy can be successfully applied to Elodea canadensis and Elodea nuttallii. They share a large suite of biological traits leading to wide niche overlaps through the growing season. And the measured environmental variables do not differentially influence their growth rates, which are, in turn, controlled by a similar group of biological traits. In this way, the different invasiveness patterns of E. canadensis and E. nuttallii could be solely due to the ecological drift and their ecological dynamic could follow neutral rules.  
  Address [Herault, Bruno] Univ Antilles Guyane, INRA, UMR Ecol Forets Guyane, F-97379 Kourou, France, Email: Bruno.Herault@cirad.fr  
  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 1387-3547 ISBN Medium  
  Area Expedition Conference  
  Notes (down) ISI:000258704400015 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 131  
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