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Author Roggy, J.-C. ;Schimann, H.;Sabatier, D.;Molino, J.-F.;Freycon, V.;Domenach, A.-M. pdf  doi
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  Title Complementary N Uptake Strategies between Tree Species in Tropical Rainforest Type Journal Article
  Year 2014 Publication International Scholarly Research Notices Abbreviated Journal ISRN  
  Volume 2014 Issue (down) Article ID 427194 Pages 1-6  
  Keywords  
  Abstract Within tree communities, the differential use of soil N mineral resources, a key factor in ecosystem functioning, may reflect functional complementarity, a major mechanism that could explain species coexistence in tropical rainforests. Eperua falcata and Dicorynia guianensis, two abundant species cooccurring in rainforests of French Guiana, were chosen as representative of two functional groups with complementary N uptake strategies (contrasting leaf d15N signatures related to the d15N of their soil N source, NO3- or NH4+). The objectives were to investigate if these strategies occurred under contrasted soil N resources in sites with distinct geological substrates representative of the coastal rainforests. Results showed that species displayed contrasting leaf d15N signatures on both substrates, confirming their complementary N uptake strategy. Consequently, their leaf 15N can be used to trace the presence of inorganic N-forms in soils (NH4+ and NO3-) and thus to indicate the capacity of soils to provide each of these two N sources to the plant community.  
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  Call Number EcoFoG @ webmaster @ Serial 576  
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Author Lebrini, M.; Robert, F.; Roos, C. pdf  url
openurl 
  Title Adsorption properties and inhibition of C38 steel corrosion in hydrochloric solution by some indole derivates: Temperature effect, activation energies, and thermodynamics of adsorption Type Journal Article
  Year 2013 Publication International Journal of Corrosion Abbreviated Journal Int. J. Corros.  
  Volume 2013 Issue (down) Article ID 139798 Pages 13  
  Keywords  
  Abstract The corrosion rates in the presence of some indole derivates, namely, 9H-pyrido[3,4-b]indole (norharmane) and 1-methyl-9H-pyrido[3,4-b]indole (harmane), as inhibitors of C38 steel corrosion inhibitor in 1 M HCl solution, were measured by potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) techniques, in the range of temperatures from 25 to 55 °C. Results obtained revealed that the organic compounds investigated have inhibiting properties for all temperatures. The inhibition was assumed to occur via adsorption of the indole molecules on the metal surface. Adsorption of indole derivates was found to follow the Langmuir isotherm. The apparent activation energies, enthalpies, and entropies of the dissolution process and the free energies and enthalpies for the adsorption process were determined by potentiodynamic polarization and electrochemical impedance. The fundamental thermodynamic functions were used to collect important information about indole inhibitory behaviour. © 2013 M. Lebrini et al.  
  Address Laboratoire Matériaux et Molécules en Milieu Amazonien, UAG-UMR ECOFOG, Campus Trou Biran, 97337 Cayenne, French Guiana  
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  Notes Export Date: 4 July 2013; Source: Scopus; Art. No.: 139798 Approved no  
  Call Number EcoFoG @ webmaster @ Serial 495  
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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 (down) 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 ISI:000259290200004 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 130  
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Author Herault, B.; Thoen, D. openurl 
  Title Diversity of plant assemblages in isolated depressional wetlands from Central-Western Europe Type Journal Article
  Year 2008 Publication Biodiversity and Conservation Abbreviated Journal Biodivers. Conserv.  
  Volume 17 Issue (down) 9 Pages 2169-2183  
  Keywords closed depressions; connectivity; fens; forest; grassland; habitat area; landscape matrix  
  Abstract A closed depression is defined as a geomorphologic element where a sediment depository is encircled by hillslopes. Despite the fact that closed depressions are often the only stagnant water points in many European landscapes, few ecological researches on their plant assemblages have been done. The main goal of this study was to give first results of the environmental factors responsible for the vegetation composition, richness and rarity in the closed depressions of the Lorraine biogeographical district (Belgium, France and grand-duche de Luxembourg). We surveyed for plant presence 85 forest and 77 grassland closed depressions. For each site, wetland area, local environmental factors and regional connectivities registered. For each species, the Ellenberg values were compiled. To investigate the main source of variation in species composition and in species richness (including richness in rare species), Non-metric Multidimensional Scaling analyses and Generalized Linear Models were respectively used. Species pools in forest (forest and preforest species) and in grassland (bog plants, pioneers, helophytes) were quite different. In both landscapes, a gradient from plants typical of basic high-productive soils to plants typical of acid low-productive soils reflects a shared successional gradient. The accumulation of organic matter allowed the establishment of Sphagnum spp., which slowly acidified the soil and thus acted as ecosystem engineers for the arrival of bog plants. Moreover, the species composition was additionally driven by the plant light tolerance in forests and by the plant water requirements in grasslands. Mechanisms of species accumulation (increase in species richness) were different in forests and in grasslands: respectively related to the plant light tolerance and to the wetland area. At the regional level, the averaged soil productivity was negatively related to the richness in rare species. Indeed, perennial highly-competitive plants such as Glyceria spp., Iris pseudacorus or Urtica dioica impeded the establishment of smaller and rarer species. At the habitat level, isolated closed depressions (due to either low connectivity or low grazing pressure) have more habitat rare species, giving evidences of dispersal limitation in plant assemblages of closed depressions.  
  Address [Herault, Bruno] Inst Bot, Ctr Ecol Vegetale & Hydrol, F-67083 Strasbourg, France, Email: bruno.herault@cirad.fr  
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  Publisher SPRINGER Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0960-3115 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000257486400008 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 135  
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Author Scotti, I.; Delph, L.F. openurl 
  Title Selective trade-offs and sex-chromosome evolution in Silene latifolia Type Journal Article
  Year 2006 Publication Evolution Abbreviated Journal Evolution  
  Volume 60 Issue (down) 9 Pages 1793-1800  
  Keywords antagonistic genes; linkage map; quantitative trait loci; sex-specific expression; Y chromosome  
  Abstract Alleles of sexually antagonistic genes (i.e., genes with alleles affecting fitness in opposite directions in the two sexes) can avoid expression in the sex to which they are detrimental via two processes: they are subsumed into the nonrecombining, sex-determining portion of the sex chromosomes or they evolve sex-limited expression. The former is considered more likely and leads to Y-chromosome degeneration. We mapped quantitative trait loci of major effect for sexually dimorphic traits of Silene latifolia to the recombining portions of the sex chromosomes and found them to exhibit sex-specific expression, with the Y chromosome in males controlling a relatively larger proportion of genetic variance than the X in females and the average autosome. Both reproductive and ecophysiological traits map to the recombining region of the sex chromosomes. We argue that genetic correlations among traits maintain recombination and polymorphism for these genes because of balancing selection in males, whereas sex-limited expression represses detrimental alleles in females. Our data suggest that the Y chromosome of S. latifolia plays a major role in the control of key metabolic activities beyond reproductive functions.  
  Address Indiana Univ, Dept Biol, Bloomington, IN 47405 USA, Email: ivan.scotti@kourou.cirad.fr  
  Corporate Author Thesis  
  Publisher SOC STUDY EVOLUTION Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0014-3820 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000241226800005 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 174  
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Author Leroy, C.; Corbara, B.; Dejean, A.; Céréghino, R. openurl 
  Title Potential sources of nitrogen in an ant-garden tank-bromeliad Type Journal Article
  Year 2009 Publication Plant Signaling and Behavior Abbreviated Journal Plant. Signal. Behav.  
  Volume 4 Issue (down) 9 Pages 868-870  
  Keywords Aechmea mertensii Camponotus femoratus nitrogen nitrogen stable isotope Pachycondyla goeldii plant-insect interactions phytotelmata  
  Abstract Epiphytic plants in general and bromeliads in particular live in a water and nutrient-stressed environment often limited in nitrogen. Thus, these plants have developed different ways to survive in such an environment. We focused on Aechmea mertensii (Bromeliaceae), which is both a tank-bromeliad and an ant-garden (AG) epiphyte initiated by either the ants Camponotus femoratus or Pachycondyla goeldii. By combining a study of plant morphology and physiology associated with aquatic insect biology, we demonstrate that the ant species influences the leaf structure of the bromeliad, the structure of the aquatic community in its tank, and nutrient assimilation by the leaves. Based on nitrogen and nitrogen stable isotope measurements of the A. mertensii leaves, the leaf litter inside of the tank and the root-embedded carton nest, we discuss the potential sources of available nitrogen for the plant based on the ant partner. We demonstrate the existence of a complex ant-plant interaction that subsequently affects the biodiversity of a broader range of organisms that are themselves likely to influence nutrient assimilation by the A. mertensii leaves in a kind of plant-invertebrate-plant feedback loop.  
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  Notes Potential sources of nitrogen in an ant-garden tank-bromeliad Approved no  
  Call Number EcoFoG @ eric.marcon @ 12 Serial 186  
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Author Coste, S.; Roggy, J.C.; Imbert, P.; Born, C.; Bonal, D.; Dreyer, E. openurl 
  Title Leaf photosynthetic traits of 14 tropical rain forest species in relation to leaf nitrogen concentration and shade tolerance Type Journal Article
  Year 2005 Publication Tree Physiology Abbreviated Journal Tree Physiol.  
  Volume 25 Issue (down) 9 Pages 1127-1137  
  Keywords functional diversity; leaf carbon; leaf nitrogen; nitrogen-use efficiency; photosynthetic capacity; tropical rain forest  
  Abstract Variability of leaf traits related to photosynthesis was assessed in seedlings from 14 tree species growing in the tropical rain forest of French Guiana. Leaf photosynthetic capacity (maximum rate of carboxylation and maximum rate of electron transport) was estimated by fitting a biochemical model of photosynthesis to response curves of net CO2 assimilation rate versus intercellular CO2 mole fraction. Leaf morphology described by leaf mass per unit leaf area (LMA), density and thickness, as well as area- and mass-based nitrogen (N) and carbon (C) concentrations, were recorded on the same leaves. Large interspecific variability was detected in photosynthetic capacity as well as in leaf structure and leaf N and C concentrations. No correlation was found between leaf thickness and density. The correlations between area- and mass-based leaf N concentration and photosynthetic capacity were poor. Conversely, the species differed greatly in relative N allocation to carboxylation and bioenergetics. Principal component analysis (PCA) revealed that, of the recorded traits, only the computed fraction of total leaf N invested in photosynthesis was tightly correlated to photosynthetic capacity. We also used PCA to test to what extent species with similar shade tolerances displayed converging leaf traits related to photosynthesis. No clear-cut ranking could be detected among the shade-tolerant groups, as confirmed by a one-way ANOVA. We conclude that the large interspecific diversity in photosynthetic capacity was mostly explained by differences in the relative allocation of N to photosynthesis and not by leaf N concentration, and that leaf traits related to photosynthetic capacity did not discriminate shade-tolerance ranking of these tropical tree species.  
  Address CNRS Ecol Forets Guyane, INRA, ENGREF,CIRAD, Unite Mixte Rech, Kourou 97387, French Guiana, Email: roggy.j@cirad.fr  
  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 ISI:000231555200005 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 230  
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Author Dejean, A.; Grangier, J.; Leroy, C.; Orivel, J.; Gilbernau, M. openurl 
  Title Nest site selection and induced response in a dominant arboreal ant species Type Journal Article
  Year 2008 Publication Naturwissenschaften Abbreviated Journal Naturwissenschaften  
  Volume 95 Issue (down) 9 Pages 885-889  
  Keywords ant-plant relationships; biotic defense; induced responses; predation  
  Abstract It is well known that arboreal ants, both territorially dominant species and plant ants (e.g., species associated with myrmecophytes or plants housing them in hollow structures), protect their host trees from defoliators. Nevertheless, the presence of an induced defense, suggested by the fact that the workers discovering a leaf wound recruit nestmates, is only known for plant ants. Based on the results from a field study, we show here (1) that colonies of Azteca chartifex, a territorially dominant, neotropical arboreal ant species, mostly selected Goupia glabra (Goupiaceae) trees in which to build their principal carton nests and (2) that plant signals induced workers to recruit nestmates, which patrol the leaves, likely providing the plant with a biotic defense. Furthermore, the number of recruited workers was clearly higher on G. glabra, their most frequently selected host tree species, than on other tree species. These results show that contrary to what was previously believed, induced responses are also found in territorially dominant arboreal ants and so are not limited to the specific associations between myrmecophytes and plant ants.  
  Address [Dejean, Alain] CNRS Guyane, UPS 5621, F-97300 Cayenne, 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 ISI:000258675700013 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 209  
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Author Coutand, C.; Dupraz, C.; Jaouen, G.; Ploquin, S.; Adam, B. openurl 
  Title Mechanical stimuli regulate the allocation of biomass in trees: Demonstration with young Prunus avium trees Type Journal Article
  Year 2008 Publication Annals of Botany Abbreviated Journal Ann. Bot.  
  Volume 101 Issue (down) 9 Pages 1421-1432  
  Keywords Prunus avium; growth; mechanical stress; bending; biomass; shoot/root ratio; wind; shelter  
  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).  
  Address [Coutand, Catherine; Jaouen, Gaelle; Ploquin, Stephane; Adam, Boris] Univ Clermont Ferrand, INRA, UMR PIAF, F-63100 Clermont Ferrand, France, Email: coutand@clermont.inra.fr  
  Corporate Author Thesis  
  Publisher OXFORD UNIV PRESS Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0305-7364 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000255987500013 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 211  
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Author Clair, B.; Fournier, M.; Prevost, M.F.; Beauchene, J.; Bardet, S. openurl 
  Title Biomechanics of buttressed trees: Bending strains and stresses Type Journal Article
  Year 2003 Publication American Journal of Botany Abbreviated Journal Am. J. Bot.  
  Volume 90 Issue (down) 9 Pages 1349-1356  
  Keywords biomechanics; buttress; Eleaocarpaceae; French Guiana; Sloanea spp.; tropical trees; wood  
  Abstract The different hypotheses about buttress function and formation mainly involve mechanical theory. Forces were applied to two trees of Sloanea spp.. a tropical genus that develops typical thin buttresses. and the three-dimensional strains were measured at different parts of the trunk base. Risks of failure were greater on the buttress sides, where shear and tangential stresses are greater, not on the ridges. in spite of high longitudinal (parallel to the grain) stresses. A simple beam model, computed from the second moment of area of digitized cross sections, is consistent with longitudinal strain variations but cannot predict accurately variations with height. Patterns of longitudinal strain variation along ridges are very different in the two individuals, owing to a pronounced lateral curvature in one specimen. The constant stress hypothesis is discussed based on these results. Without chronological data during the development of the tree. it cannot be proved that buttress formation is activated by stress or strain.  
  Address CIRAD ENGREF INRA, UMR Ecol Forets Guyane, F-97310 Kourou, Guyane Francais, France  
  Corporate Author Thesis  
  Publisher BOTANICAL SOC AMER INC Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0002-9122 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000185459000010 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 244  
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