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Author Dejean, A.; Fisher, B.L.; Corbara, B.; Rarevohitra, R.; Randrianaivo, R.; Rajemison, B.; Leponce, M.
Title Spatial Distribution of Dominant Arboreal Ants in a Malagasy Coastal Rainforest: Gaps and Presence of an Invasive Species Type Journal Article
Year 2010 Publication PLoS One Abbreviated Journal PLoS One
Volume 5 Issue (up) 2 Pages e9319
Keywords
Abstract We conducted a survey along three belt transects located at increasing distances from the coast to determine whether a non-random arboreal ant assemblage, such as an ant mosaic, exists in the rainforest on the Masoala Peninsula, Madagascar. In most tropical rainforests, very populous colonies of territorially dominant arboreal ant species defend absolute territories distributed in a mosaic pattern. Among the 29 ant species recorded, only nine had colonies large enough to be considered potentially territorially dominant; the remaining species had smaller colonies and were considered non-dominant. Nevertheless, the null-model analyses used to examine the spatial structure of their assemblages did not reveal the existence of an ant mosaic. Inland, up to 44% of the trees were devoid of dominant arboreal ants, something not reported in other studies. While two Crematogaster species were not associated with one another, Brachymyrmex cordemoyi was positively associated with Technomyrmex albipes, which is considered an invasive species-a non-indigenous species that has an adverse ecological effect on the habitats it invades. The latter two species and Crematogaster ranavalonae were mutually exclusive. On the other hand, all of the trees in the coastal transect and at least 4 km of coast were occupied by T. albipes, and were interconnected by columns of workers. Technomyrmex albipes workers collected from different trees did not attack each other during confrontation tests, indicating that this species has formed a supercolony along the coast. Yet interspecific aggressiveness did occur between T. albipes and Crematogaster ranavalonae, a native species which is likely territorially dominant based on our intraspecific confrontation tests. These results suggest that the Masoala rainforest is threatened by a potential invasion by T. albipes, and that the penetration of this species further inland might be facilitated by the low density of native, territorially dominant arboreal ants normally able to limit its progression.
Address [Dejean, Alain] CNRS, Unite Mixte Rech 8172, Kourou, France, Email: alain.dejean@wanadoo.fr
Corporate Author Thesis
Publisher PUBLIC LIBRARY SCIENCE Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1932-6203 ISBN Medium
Area Expedition Conference
Notes ISI:000274923700021 Approved no
Call Number EcoFoG @ eric.marcon @ Serial 81
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Author Roux, O.; Billen, J.; Orivel, J.; Dejean, A.
Title An Overlooked Mandibular-Rubbing Behavior Used during Recruitment by the African Weaver Ant, Oecophylla longinoda Type Journal Article
Year 2010 Publication PLoS One Abbreviated Journal PLoS One
Volume 5 Issue (up) 2 Pages e8957
Keywords
Abstract In Oecophylla, an ant genus comprising two territorially dominant arboreal species, workers are known to (1) use anal spots to mark their territories, (2) drag their gaster along the substrate to deposit short-range recruitment trails, and (3) drag the extruded rectal gland along the substrate to deposit the trails used in long-range recruitment. Here we study an overlooked but important marking behavior in which O. longinoda workers first rub the underside of their mandibles onto the substrate, and then-in a surprising posture-tilt their head and also rub the upper side of their mandibles. We demonstrate that this behavior is used to recruit nestmates. Its frequency varies with the rate at which a new territory, a sugary food source, a prey item, or an alien ant are discovered. Microscopy analyses showed that both the upper side and the underside of the mandibles possess pores linked to secretory glands. So, by rubbing their mandibles onto the substrate, the workers probably spread a secretion from these glands that is involved in nestmate recruitment.
Address [Roux, Olivier; Dejean, Alain] CNRS, UMR, Kourou, France, Email: oroux@cict.fr
Corporate Author Thesis
Publisher PUBLIC LIBRARY SCIENCE Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1932-6203 ISBN Medium
Area Expedition Conference
Notes ISI:000274209700003 Approved no
Call Number EcoFoG @ eric.marcon @ Serial 82
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Author Picard, N.; Mortier, F.; Rossi, V.; Gourlet-Fleury, S.
Title Clustering species using a model of population dynamics and aggregation theory Type Journal Article
Year 2010 Publication Ecological Modelling Abbreviated Journal Ecol. Model.
Volume 221 Issue (up) 2 Pages 152-160
Keywords Aggregation theory; Species grouping; Species richness; Tropical rainforest; Usher model
Abstract The high species diversity of some ecosystems like tropical rainforests goes in pair with the scarcity of data for most species. This hinders the development of models that require enough data for fitting. The solution commonly adopted by modellers consists in grouping species to form more sizeable data sets. Classical methods for grouping species such as hierarchical cluster analysis do not take account of the variability of the species characteristics used for clustering. In this study a clustering method based on aggregation theory is presented. It takes account of the variability of species characteristics by searching for the grouping that minimizes the quadratic error (square bias plus variance) of some model's prediction. This method allows one to check whether the gain in variance brought by data pooling compensate for the bias that it introduces. This method was applied to a data set on 94 tree species in a tropical rainforest in French Guiana, using a Usher matrix model to predict species dynamics. An optimal trade-off between bias and variance was found when grouping species. Grouping species appeared to decrease the quadratic error, except when the number of groups was very small. This clustering method yielded species groups similar to those of the hierarchical cluster analysis using Ward's method when variance was small, that is when the number of groups was small. (C) 2009 Elsevier B.V. All rights reserved.
Address [Picard, Nicolas; Mortier, Frederic; Rossi, Vivien; Gourlet-Fleury, Sylvie] CIRAD, F-34398 Montpellier 5, France, Email: nicolas.picard@cirad.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 0304-3800 ISBN Medium
Area Expedition Conference
Notes ISI:000273628800004 Approved no
Call Number EcoFoG @ eric.marcon @ Serial 85
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Author Ruelle, J.; Yamamoto, H.; Thibaut, B.
Title Growth Stresses and Cellulose Structural Parameters in Tension and Normal Wood from Three Tropical Rainforest Angiosperm Species Type Journal Article
Year 2007 Publication BioResources Abbreviated Journal BioResources
Volume 2 Issue (up) 2 Pages 235-251
Keywords Cellulose; Microfibril angle; Crystallite size; Tension wood; Tropical rainforest; Growth stresses
Abstract Few studies have been conducted about relation between cellulose parameters and biomechanical properties of wood in tropical angiosperms species. For this purpose, on 13 trees from 3 species of French Guyana tropical rainforest in a clear active process of restoring verticality, i) growth strains were measured in situ in order to determine the occurrence of tension wood within samples and ii) cellulose structural parameters were estimated on all the samples using X-ray diffraction method. Crystallite size was estimated from the full-width at half-maximum of the Miller index (002) arc diffraction and angle T was measured following Cave's method. Relationships between these parameters and growth stresses were good and the variations between normal and tension wood were significant, i. e. a lower angle T and a larger crystallite size in tension wood. In order to have a good estimation of the microfibril angle in the main layer of the secondary wall for each species, an experimental calibration was done between angle T and microfibril angle observed with scanning electron microscopy.
Address [Ruelle, Julien; Thibaut, Bernard] UMR EcoFoG, Kourou 97387, Guyana, Email: ruelle_j@kourou.cirad.fr
Corporate Author Thesis
Publisher NORTH CAROLINA STATE UNIV DEPT WOOD & PAPER SCI Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1930-2126 ISBN Medium
Area Expedition Conference
Notes ISI:000263689300009 Approved no
Call Number EcoFoG @ eric.marcon @ Serial 122
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Author Tindo, M.; Kenne, M.; Dejean, A.
Title Advantages of multiple foundress colonies in Belonogaster juncea juncea L.: greater survival and increased productivity Type Journal Article
Year 2008 Publication Ecological Entomology Abbreviated Journal Ecol. Entomol.
Volume 33 Issue (up) 2 Pages 293-297
Keywords colony development; evolution of eusociality; fitness; Polistinae; productivity
Abstract 1. The ecological hypothesis predicts that multiple foundress colonies of social wasps may have a better survival rate and produce more brood per capita than single foundress colonies. With the aim of verifying if these characteristics exist in the primitively eusocial wasp species Belonogaster juncea juncea (L.), we monitored 49 foundations, including 13 single and 36 multiple foundress colonies, in Cameroon. 2. Multiple foundress colonies were significantly more successful than single foundress colonies in producing at least one adult. 3. The total productivity of the colonies increased significantly with the number of associated foundresses, but the productivity per capita did not. No single foundress colony reached the sexual phase, while eight (21.6%) multiple foundress colonies did. Males were produced in only five colonies, so that the sex ratio was biased in favour of females. 4. These results suggest that because of the strong ecological constraints on solitary nesting, survival and high colony productivity are two advantages of multiple foundress colonies in B. j. juncea. 5. The decreasing per capita productivity concomitant with an increasing number of females noted in this study illustrates once again Michener's paradox. The coefficient of variance of the per capita productivity significantly decreased with group size, as Wenzel and Pickering suggested in the model they created to explain the paradox. 6. Ecological factors may act in conjunction with other factors, such as genetic relatedness between associated foundresses, to promote joining behaviour in B. j. juncea.
Address [Tindo, Maurice; Kenne, Martin] Univ Douala, Fac Sci, BP Douala, Cameroon, Email: jtindo2000@yahoo.fr
Corporate Author Thesis
Publisher BLACKWELL PUBLISHING Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0307-6946 ISBN Medium
Area Expedition Conference
Notes ISI:000253710000017 Approved no
Call Number EcoFoG @ eric.marcon @ Serial 142
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Author Brendel, O.; Le Thiec, D.; Scotti-Saintagne, C.; Bodenes, C.; Kremer, A.; Guehl, J.M.
Title Quantitative trait loci controlling water use efficiency and related traits in Quercus robur L Type Journal Article
Year 2008 Publication Tree Genetics & Genomes Abbreviated Journal Tree Genet. Genomes
Volume 4 Issue (up) 2 Pages 263-278
Keywords Quercus robur; carbon isotope composition; delta C-13; water use efficiency; QTL
Abstract Genetic variation for intrinsic water use efficiency (W-i) and related traits was estimated in a full-sib family of Quercus robur L. over 3 years. The genetic linkage map available for this F1 family was used to locate quantitative trait loci (QTL) for W-i, as estimated by leaf carbon stable isotope composition (delta C-13) or the ratio of net CO2 assimilation rate (A) to stomatal conductance to water vapour (g(w)) and related leaf traits. Gas exchange measurements were used to standardize estimates of A and g(w) and to model the sensitivity of gw to leaf-to-air vapour pressure deficit (sg(VPD)). delta C-13 varied by more than 3% among the siblings, which is equivalent to 40% variation of W-i. Most of the studied traits exhibited high clonal mean repeat-abilities (> 50%; proportion of clonal mean variability in global variance). Repeatabilities for delta C-13, leaf mass per area (LMA) and leaf nitrogen content were higher than 70%. For delta C-13, ten QTLs were detected, one of which was detected repeatedly for all 3 years and consistently explained more than 20% of measured variance. Four genomic regions were found in which co-localizing traits linked variation in W-i to variations in leaf chlorophyll and nitrogen content, LMA and sg(VPD). A positive correlation using clonal means between delta C-13 and A/g(w), as well as a co-localisation of QTL detected for both traits, can be seen as validation of the theoretical model linking the genetic architecture of these two traits.
Address [Brendel, Oliver; Le Thiec, Didier; Guehl, Jean-Marc] Ctr INRA Nancy, UMR INRA UHP 1137, F-54280 Seichamps, France, Email: brendel@nancy.inra.fr
Corporate Author Thesis
Publisher SPRINGER HEIDELBERG Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1614-2942 ISBN Medium
Area Expedition Conference
Notes ISI:000253091100013 Approved no
Call Number EcoFoG @ eric.marcon @ Serial 143
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Author Schimann, H.; Ponton, S.; Hattenschwiler, S.; Ferry, B.; Lensi, R.; Domenach, A.M.; Roggy, J.C.
Title Differing nitrogen use strategies of two tropical rainforest late successional tree species in French Guiana: Evidence from N-15 natural abundance and microbial activities Type Journal Article
Year 2008 Publication Soil Biology & Biochemistry Abbreviated Journal Soil Biol. Biochem.
Volume 40 Issue (up) 2 Pages 487-494
Keywords soil; litter; nitrate; nitrification; tree rooting; N-15; Eperua falcata; Dicorynia guianensis; tropical forest
Abstract Previous studies in lowland tropical rainforests of French Guiana showed that, among non-N-2-fixing trees, two groups of late successional species contrasting in their leaf N-15 natural abundance coexist, suggesting two different main ways of nitrogen acquisition. Two abundant late-successional species typically co-occurring in rainforests in French Guiana, namely Eperua falcata and Dicorynia guianensis, were chosen as representative of each group. Stable isotope techniques and measurements of potentials of microbial N transformation were performed to assess to what extent leaf N-15 natural abundance of these species could be related to (i) delta N-15 signatures of soil mineral N sources and (ii) the capacity of soil to express nitrification and denitrification (both processes being directly involved in the balance between NH4+ and NO3-). Soil delta N-15-NH4+ was roughly similar to leaf delta N-15 of D. guianensis (around 3.5 parts per thousand), suggesting a preferential use of NH4+, whereas in E. falcata, leaf delta N-15 values were closer to root delta N-15-NO3- values (0.2 and -2.0 parts per thousand, respectively), suggesting a preferential use of NO3-. These differences in N source utilization were not accompanied by differences in availability in soil NO3- or in intensity of microbial functions responsible for soil N mineral evolution. However, (i) under both tree species, these functions showed clear spatial partitioning, with denitrification occurring potentially in soil and nitrification in the litter layer, and (ii) E falcata fine roots colonized the litter layer much more strongly than D. guianensis fine roots. This strongly suggests that (i) the contrasted leaf delta N-15 values found in the two late-successional species reveal distinct N acquisition strategies and (ii) the ability of roots to predominantly exploit the litter layer (E falcata) or the soil (D. guianensis) may constitute an important explanation of the observed differences. A complementarity between tree species, based on mineral N resource partitioning (itself resulting from a spatially structured location of the microbial functions responsible for the balance between NH4+ and NO3-), n thus be supposed. (c) 2007 Elsevier Ltd. All rights reserved.
Address [Schimann, Heidy; Ponton, Stephane; Domenach, Anne-Marie; Roggy, Jean-Christophe] UMR Ecol Forets Guyane, F-97387 Kourou, French Guiana, Email: heidy_schimann@cirad.fr
Corporate Author Thesis
Publisher PERGAMON-ELSEVIER SCIENCE LTD Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0038-0717 ISBN Medium
Area Expedition Conference
Notes ISI:000251655800021 Approved no
Call Number EcoFoG @ eric.marcon @ Serial 146
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Author Herault, B.
Title Reconciling niche and neutrality through the Emergent Group approach Type Journal Article
Year 2007 Publication Perspectives in Plant Ecology Evolution and Systematics Abbreviated Journal Perspect. Plant Ecol. Evol. Syst.
Volume 9 Issue (up) 2 Pages 71-78
Keywords Biodiversity; ecological equivalency; biological traits; neutral theory; niche differentiation; redundancy
Abstract Both niche and neutral theories have been suggested as potential frameworks for modelling biodiversity. Niche models assume that biological traits represent evolutionary adaptations and define individuals in terms of functional trade-offs. Neutral models assume that all individuals at a single trophic level are functionally equivalent on a per capita basis with respect to their birth, death, dispersal and speciation. The opinion of many researchers is that neutral and niche processes operate simultaneously to generate diversity without knowing how the unification of both models can be achieved. Recently, several theoretical papers have reported evidence on the evolutionary emergence of niche structures shaping the emergence of groups of similar species. In this way, an Emergent Group is defined as a set of species that have a similar functional niche owing to a convergent ecological strategy. Central to the Emergent Group concept are the assumptions of functional equivalence within and of functional divergence between Emergent Groups. Within an Emergent Group, species richness is subject to a zero-sum rule set by the balance between the rate of individual loss and of immigration. Between Emergent Groups, tradeoffs such as seed size/seedling competitivity, investment in reproductive system/investment in vegetative systems or competitive ability/predator invulnerability are cornerstones of the evolutionary divergence. Delineating Emergent Groups amounts to reaching a compromise between maximizing niche differentiation (i.e. maximizing differences in functional tradeoffs) between Emergent Groups and maximizing neutrality within Emergent Groups. Up to now, the Emergent Group concept has been mostly proposed by theoretical scientists but it should be tested by empirical ecologists. The way in which niche and neutral models could be combined provides a profitable opportunity for theoretical and empirical scientists to collaborate fruitfully. (c) 2007 Rubel Foundation, ETH Zurich. Published by Elsevier GmbH. All rights reserved.
Address [Herault, Bruno] Univ Antilles Guyane, UMR Ecol Forets Guyane, F-97379 Kourou, France, Email: Bruno.Herault@cirad.fr
Corporate Author Thesis
Publisher ELSEVIER GMBH, URBAN & FISCHER VERLAG Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1433-8319 ISBN Medium
Area Expedition Conference
Notes ISI:000251685100002 Approved no
Call Number EcoFoG @ eric.marcon @ Serial 147
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Author Coutand, C.; Fournier, M.; Moulia, B.
Title The gravitropic response of poplar trunks: Key roles of prestressed wood regulation and the relative kinetics of cambial growth versus wood maturation Type Journal Article
Year 2007 Publication Plant Physiology Abbreviated Journal Plant Physiol.
Volume 144 Issue (up) 2 Pages 1166-1180
Keywords
Abstract In tree trunks, the motor of gravitropism involves radial growth and differentiation of reaction wood (Archer, 1986). The first aim of this study was to quantify the kinematics of gravitropic response in young poplar (Populus nigra x Populus deltoides, 'I4551') by measuring the kinematics of curvature fields along trunks. Three phases were identified, including latency, upward curving, and an anticipative autotropic decurving, which has been overlooked in research on trees. The biological and mechanical bases of these processes were investigated by assessing the biomechanical model of Fournier et al. (1994). Its application at two different time spans of integration made it possible to test hypotheses on maturation, separating the effects of radial growth and cross section size from those of wood prestressing. A significant correlation between trunk curvature and Fournier's model integrated over the growing season was found, but only explained 32% of the total variance. Moreover, over a week's time period, the model failed due to a clear out phasing of the kinetics of radial growth and curvature that the model does not take into account. This demonstrates a key role of the relative kinetics of radial growth and the maturation process during gravitropism. Moreover, the degree of maturation strains appears to differ in the tension woods produced during the upward curving and decurving phases. Cell wall maturation seems to be regulated to achieve control over the degree of prestressing of tension wood, providing effective control of trunk shape.
Address Univ Clermont Ferrand, Inst Natl Recherche Agronom, Physiol Integree Arbre Fruitier, Unite Mixte Recherche 547, F-63100 Clermont Ferrand, France, Email: coutand@clermont.inra.fr
Corporate Author Thesis
Publisher AMER SOC PLANT BIOLOGISTS Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0032-0889 ISBN Medium
Area Expedition Conference
Notes ISI:000247075000055 Approved no
Call Number EcoFoG @ eric.marcon @ Serial 162
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Author Baraloto, C.; Morneau, F.; Bonal, D.; Blanc, L.; Ferry, B.
Title Seasonal water stress tolerance and habitat associations within four neotropical tree genera Type Journal Article
Year 2007 Publication Ecology Abbreviated Journal Ecology
Volume 88 Issue (up) 2 Pages 478-489
Keywords drought tolerance; French Guiana; photosynthetic capacity; phylogenetically independent contrast; relative growth rate; seasonally flooded forest; specific leaf area; torus translation method; tropical forest
Abstract We investigated the relationship between habitat association and physiological performance in four congeneric species pairs exhibiting contrasting distributions between seasonally flooded and terra firme habitats in lowland tropical rain forests of French Guiana, including Virola and Iryanthera ( Myristicaceae), Symphonia ( Clusiaceae), and Eperua (Caesalpiniaceae). We analyzed 10-year data sets of mapped and measured saplings ( stems >= 150 cm in height and < 10 cm diameter at breast height [dbh]) and trees ( stems >= 10 cm dbh) across 37.5 ha of permanent plots covering a 300-ha zone, within which seasonally flooded areas ( where the water table never descends below 1 m) have been mapped. Additionally, we tested the response of growth, survival, and leaf functional traits of these species to drought and flood stress in a controlled experiment. We tested for habitat preference using a modi. cation of the torus translation method. Strong contrasting associations of the species pairs of Iryanthera, Virola, and Symphonia were observed at the sapling stage, and these associations strengthened for the tree stage. Neither species of Eperua was significantly associated with flooded habitats at the sapling stage, but E. falcata was significantly and positively associated with flooded forests at the tree stage, and trees of E. grandiflora were found almost exclusively in nonflooded habitats. Differential performance provided limited explanatory support for the observed habitat associations, with only congeners of Iryanthera exhibiting divergent sapling survival and tree growth. Seedlings of species associated with flooded forest tended to have higher photosynthetic capacity than their congeners at field capacity. In addition, they tended to have the largest reductions in leaf gas exchange and growth rate in response to experimental drought stress and the least reductions in response to experimental inundation. The corroboration of habitat association with differences in functional traits and, to a lesser extent, measures of performance provides an explanation for the regional coexistence of these species pairs. We suggest that specialization to seasonally flooded habitats may explain patterns of adaptive radiation in many tropical tree genera and thereby provide a substantial contribution to regional tree diversity.
Address INRA, UMR Ecol Forets Guyane, Kourou, French Guiana, Email: baraloto@botany.ufl.edu
Corporate Author Thesis
Publisher ECOLOGICAL SOC AMER Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0012-9658 ISBN Medium
Area Expedition Conference
Notes ISI:000245668400021 Approved no
Call Number EcoFoG @ eric.marcon @ Serial 165
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