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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 0021-8901 ISBN Medium
Area Expedition Conference
Notes ISI:000279405100012 Approved no
Call Number (up) EcoFoG @ eric.marcon @ Serial 53
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Author Ruiz-Gonzalez, M.X.; Corbara, B.; Leroy, C.; Dejean, A.; Orivel, J.
Title The Weaver Wasp: Spinning Fungus into a Nest Type Journal Article
Year 2010 Publication Biotropica Abbreviated Journal Biotropica
Volume 42 Issue 4 Pages 402-404
Keywords Allomerus decemarticulatus; French Guiana; Hirtella physophora; nest architecture; Nitela constructor; wasp biology
Abstract Wasp nests range from simple to complex structures made of paper or mud. Here, we show that a Neotropical wasp of the genus Nitela builds its nest entirely by weaving endophytic fungal hyphae and spider silk harvested from the leaves growing in the understory of the rain forest in French Guiana.
Address [Ruiz-Gonzalez, Mario X.; Orivel, Jerome] Univ Toulouse, UPS, EDB, Lab Evolut & Divers Biol, F-31062 Toulouse, France, Email: orivel@cict.fr
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 0006-3606 ISBN Medium
Area Expedition Conference
Notes ISI:000279438900002 Approved no
Call Number (up) EcoFoG @ eric.marcon @ Serial 54
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Author Baraloto, C.; Couteron, P.
Title Fine-scale Microhabitat Heterogeneity in a French Guianan Forest Type Journal Article
Year 2010 Publication Biotropica Abbreviated Journal Biotropica
Volume 42 Issue 4 Pages 420-428
Keywords canopy gap; geostatistics; light availability; microclimate; soil moisture; soil nutrients; topography
Abstract We examined fine-scale heterogeneity of environmental conditions in a primary rain forest in French Guiana to describe variation in microhabitats that plants may experience during establishment. We characterized both the range as well as the spatial structuring of 11 environmental factors important for seedling establishment in six hexagonal sampling grids, one each in gap and understory sites at three points representing the predominant geomorphic units in this primary forest. Each grid contained 37 sampling points separated by 31 cm-20 m. Monte-Carlo tests of semivariograms against complete spatial randomness indicated that for many variables in all six sampling grids, spatial dependence did not exceed 1 m. A principal component analysis of all sampling points revealed a lack of spatial microhabitat structure, rather than homogeneous patches associated with canopy structure or geomorphology. Our results suggest that ample fine-scale spatial heterogeneity exists to support the coexistence of plant species with differential abiotic requirements for regeneration.
Address [Baraloto, Christopher] INRA, UMR Ecol Forets Guyane, F-97387 Kourou, France, Email: chris.baraloto@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 0006-3606 ISBN Medium
Area Expedition Conference
Notes ISI:000279438900005 Approved no
Call Number (up) EcoFoG @ eric.marcon @ Serial 55
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Author Dejean, A.; Leroy, C.; Corbara, B.; Roux, O.; Cereghino, R.; Orivel, J.; Boulay, R.
Title Arboreal Ants Use the "Velcro (R) Principle'' to Capture Very Large Prey Type Journal Article
Year 2010 Publication PLoS One Abbreviated Journal PLoS One
Volume 5 Issue 6 Pages e11331
Keywords
Abstract Plant-ants live in a mutualistic association with host plants known as "myrmecophytes'' that provide them with a nesting place and sometimes with extra-floral nectar (EFN) and/or food bodies (FBs); the ants can also attend sap-sucking Hemiptera for their honeydew. In return, plant-ants, like most other arboreal ants, protect their host plants from defoliators. To satisfy their nitrogen requirements, however, some have optimized their ability to capture prey in the restricted environment represented by the crowns of trees by using elaborate hunting techniques. In this study, we investigated the predatory behavior of the ant Azteca andreae which is associated with the myrmecophyte Cecropia obtusa. We noted that up to 8350 ant workers per tree hide side-by-side beneath the leaf margins of their host plant with their mandibles open, waiting for insects to alight. The latter are immediately seized by their extremities, and then spread-eagled; nestmates are recruited to help stretch, carve up and transport prey. This group ambush hunting technique is particularly effective when the underside of the leaves is downy, as is the case for C. obtusa. In this case, the hook-shaped claws of the A. andreae workers and the velvet-like structure of the underside of the leaves combine to act like natural Velcro (R) that is reinforced by the group ambush strategy of the workers, allowing them to capture prey of up to 13,350 times the mean weight of a single worker.
Address [Dejean, Alain; Leroy, Celine; Roux, Olivier; Orivel, Jerome] CNRS, Ecol Forets Guyane UMR CNRS 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:000279140800028 Approved no
Call Number (up) EcoFoG @ eric.marcon @ Serial 56
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Author Stahl, C.; Burban, B.; Bompy, F.; Jolin, Z.B.; Sermage, J.; Bonal, D.
Title Seasonal variation in atmospheric relative humidity contributes to explaining seasonal variation in trunk circumference of tropical rain-forest trees in French Guiana Type Journal Article
Year 2010 Publication Journal of Tropical Ecology Abbreviated Journal J. Trop. Ecol.
Volume 26 Issue Pages 393-405
Keywords bark; drought; secondary growth; seasonality; tropical rain forest; water
Abstract Large seasonal variation in the rate of change in girth of tropical rain-forest tree species has been described, but its origin is still under debate. We tested whether this variation might be related to variation in atmospheric relative humidity through its influence on bark water content and thickness. Variation in trunk circumference of 182 adult trees was measured about twice a month in an undisturbed tropical rain forest over 18 mo using dendrometers. Furthermore, a laboratory experiment was conducted to test the direct influence of relative air humidity on bark water content and thickness. in the field, most trees displayed highly positive rates of change in girth at the onset of the wet season, while a quarter of the trees displayed negative changes during long dry seasons, whatever their total annual growth. This variation was correlated with environmental conditions, particularly with atmospheric relative humidity. Trees with high bark water content and thickness displayed a stronger decrease in girth during the dry season. in the chamber experiment, desiccation induced a decrease in the diameter of the trunk sections in tandem with a decrease in bark water content. As a result, seasonal variation in the rate of change in girth of tropical rain-forest trees reflects variation in trunk biophysical properties, through the influence of relative humidity on bark properties. but not directly variation in secondary growth.
Address [Stahl, Clement; Burban, Benoit; Bompy, Felix; Jolin, Zachari B.; Sermage, Juliette; Bonal, Damien] INRA, UMR Ecol Forets Guyane 745, Kourou 97387, French Guiana, Email: bonal@nancy.inra.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 ISI:000279100600005 Approved no
Call Number (up) EcoFoG @ eric.marcon @ Serial 57
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Author Quesada, C.A.; Lloyd, J.; Schwarz, M.; Patino, S.; Baker, T.R.; Czimczik, C.; Fyllas, N.M.; Martinelli, L.; Nardoto, G.B.; Schmerler, J.; Santos, A.J.B.; Hodnett, M.G.; Herrera, R.; Luizao, F.J.; Arneth, A.; Lloyd, G.; Dezzeo, N.; Hilke, I.; Kuhlmann, I.; Raessler, M.; Brand, W.A.; Geilmann, H.; Moraes, J.O.; Carvalho, F.P.; Araujo, R.N.; Chaves, J.E.; Cruz, O.F.; Pimentel, T.P.; Paiva, R.
Title Variations in chemical and physical properties of Amazon forest soils in relation to their genesis Type Journal Article
Year 2010 Publication Biogeosciences Abbreviated Journal Biogeosciences
Volume 7 Issue 5 Pages 1515-1541
Keywords
Abstract Soil samples were collected in six South American countries in a total of 71 different 1 ha forest plots across the Amazon Basin as part of the RAINFOR project. They were analysed for total and exchangeable cations, C, N, pH with various P fractions also determined. Physical properties were also examined and an index of soil physical quality proposed. A diverse range of soils was found. For the western areas near the Andean cordillera and the southern and northern fringes, soils tend to be distributed among the lower pedogenetic levels, while the central and eastern areas of Amazonia have more intensely weathered soils. This gives rise to a large variation of soil chemical and physical properties across the Basin, with soil properties varying predictably along a gradient of pedogenic development. Nutrient pools generally increased slightly in concentration from the youngest to the intermediate aged soils after which a gradual decline was observed with the lowest values found in the most weathered soils. Soil physical properties were strongly correlated with soil fertility, with favourable physical properties occurring in highly weathered and nutrient depleted soils and with the least weathered, more fertile soils having higher incidence of limiting physical properties. Soil phosphorus concentrations varied markedly in accordance with weathering extent and appear to exert an important influence on the nitrogen cycle of Amazon forest soils.
Address [Quesada, C. A.; Lloyd, J.; Baker, T. R.; Fyllas, N. M.] Univ Leeds, Sch Geog, Earth & Biosphere Inst, Leeds LS2 9JT, W Yorkshire, England, Email: betoquesada@yahoo.com.br
Corporate Author Thesis
Publisher COPERNICUS GESELLSCHAFT MBH Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1726-4170 ISBN Medium
Area Expedition Conference
Notes ISI:000278184500011 Approved no
Call Number (up) EcoFoG @ eric.marcon @ Serial 58
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Author Cereghino, R.; Leroy, C.; Dejean, A.; Corbara, B.
Title Ants mediate the structure of phytotelm communities in an ant-garden bromeliad Type Journal Article
Year 2010 Publication Ecology Abbreviated Journal Ecology
Volume 91 Issue 5 Pages 1549-1556
Keywords Aechmea mertensii; ant-gardens; biodiversity; bromeliads; Camponotus femoratus; Crematogaster levior; macroinvertebrates; mutualism; Pachycondyla goeldii; phytotelmata; secondary forest; Sinnamary; French Guiana; species interactions
Abstract The main theories explaining the biological diversity of rain forests often confer a limited understanding of the contribution of interspecific interactions to the observed patterns. We show how two-species mutualisms can affect much larger segments of the invertebrate community in tropical rain forests. Aechmea mertensii (Bromeliaceae) is both a phytotelm (plant-held water) and an ant-garden epiphyte. We studied the influence of its. associated ant species (Pachycondyla goeldii and Camponotus femoratus) on the physical characteristics of the plants, and, subsequently, on the diversity of the invertebrate communities that inhabit their tanks. As dispersal agents for the bromeliads, P. goeldii and C. femoratus influence the shape and size of the bromeliad by determining the location of the seedling, from exposed to partially shaded areas. By coexisting on a local scale, the two ant species generate a gradient of habitat conditions in terms of available resources (space and food) for aquatic invertebrates, the diversity of the invertebrate communities increasing with greater volumes of water and fine detritus. Two-species mutualisms are widespread in nature, but their influence on the diversity of entire communities remains largely unexplored. Because macroinvertebrates constitute an important part of animal production in all ecosystem types, further investigations should address the functional implications of such indirect effects.
Address [Cereghino, Regis] Univ Toulouse, UPS, INPT, Lab Ecol Fonct,EcoLab, F-31062 Toulouse, France, Email: cereghin@cict.fr
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:000277867600030 Approved no
Call Number (up) EcoFoG @ eric.marcon @ Serial 59
Permanent link to this record
 

 
Author Derory, J.; Scotti-Saintagne, C.; Bertocchi, E.; Le Dantec, L.; Graignic, N.; Jauffres, A.; Casasoli, M.; Chancerel, E.; Bodenes, C.; Alberto, F.; Kremer, A.
Title Contrasting relationships between the diversity of candidate genes and variation of bud burst in natural and segregating populations of European oaks Type Journal Article
Year 2010 Publication Heredity Abbreviated Journal Heredity
Volume 104 Issue 5 Pages 438-448
Keywords nucleotide diversity; candidate gene; QTL; Qeurcus petraea
Abstract Nucleotide diversity was assessed within nine candidate genes (CGs) (in total 4.6 kb) for the time of bud burst in nine sessile oak (Quercus petraea) populations distributed in central and northern Europe. The sampled populations were selected on the basis of their contrasting times of bud burst observed in common garden experiments (provenance tests). The CGs were selected according to their expression profiles during the transition from quiescent to developing buds and/or their functional role in model plants. The overall nucleotide diversity was large (pi(tot) = 6.15 x 10(-3); pi(silent) = 11.2 x 10(-3)), but population differentiation was not larger than for microsatellites. No outlier single-nucleotide polymorphism (SNP) departing from neutral expectation was found among the total of 125 SNPs. These results contrasted markedly with the significant associations that were observed between the CGs and bud burst in segregating populations. Quantitative trait loci (QTLs) for bud burst were identified for 13 year*site seasonal observations in a cloned mapping pedigree. Nineteen QTLs were detected, and QTLs located on linkage groups 2, 5 and 9 contributed repeatedly to more than 12% of the phenotypic variation of the trait. Eight genes were polymorphic in the two parents of the pedigree and could be mapped on the existing genetic map. Five of them located within the confidence intervals of QTLs for bud burst. Interestingly, four of them located within the three QTLs exhibiting the largest contributions to bud burst. Heredity (2010) 104, 438-448; doi:10.1038/hdy.2009.134; published online 7 October 2009
Address [Derory, J.; Scotti-Saintagne, C.; Bertocchi, E.; Graignic, N.; Jauffres, A.; Casasoli, M.; Chancerel, E.; Bodenes, C.; Alberto, F.; Kremer, A.] INRA, BIOGECO UMR1202, F-33610 Cestas, France, Email: antoine.kremer@pierroton.inra.fr
Corporate Author Thesis
Publisher NATURE PUBLISHING GROUP Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0018-067X ISBN Medium
Area Expedition Conference
Notes ISI:000276952000005 Approved no
Call Number (up) EcoFoG @ eric.marcon @ Serial 60
Permanent link to this record
 

 
Author Jaouen, G.; Fournier, M.; Almeras, T.
Title Thigmomorphogenesis versus light in biomechanical growth strategies of saplings of two tropical rain forest tree species Type Journal Article
Year 2010 Publication Annals of Forest Science Abbreviated Journal Ann. For. Sci.
Volume 67 Issue 2 Pages 211
Keywords biomechanics; thigmomorphogenesis; height growth strategies; tropical rain forest; French Guiana
Abstract In the dense tropical rainforest understorey, saplings exhibit different growth strategies aiming at reaching light levels better fitting their ecology. Investing mainly in height growth, at the expense of their width, a lot are close to mechanical instability. Tachigali melinonii, a long living heliophilic tree species, is frequently observed to be extremely slender and supported by neighbours. Such observations suggest an active growth control through the perception of mechanical environment. Mechanical environment or light availability, which one is the most influent on growth and slenderness (H/D)? To test this question, we recorded growth of control and staked saplings of two species with contrasting habits and ecology: T. melinonii, and Dicorynia guianensis, along a natural light gradient. Dicorynia, the more stable, responded more clearly to the staking treatment, showing slenderness increase when light is available, whereas for Tachigali, only light availability governed growth. For Tachigali, growth allocation is mainly governed by light availability and ontogeny, whereas Dicorynia is probably similar to the average tree strategy, using the thigmomorphogenetic physiological process to control its stability.
Address [Jaouen, Gaelle; Almeras, Tancrede] Univ Antilles Guyane, INRA, CNRS,Cirad, Unite Mixte Rech Ecol Forets Guyane,AgroParisTech, Kourou 97379, French Guiana, Email: gaelle.jaouen@ecofog.gf
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 ISI:000276507100012 Approved no
Call Number (up) EcoFoG @ eric.marcon @ Serial 61
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Author Baraloto, C.; Marcon, E.; Morneau, F.; Pavoine, S.; Roggy, J.C.
Title Integrating functional diversity into tropical forest plantation designs to study ecosystem processes Type Journal Article
Year 2010 Publication Annals of Forest Science Abbreviated Journal Ann. For. Sci.
Volume 67 Issue 3 Pages 303
Keywords complementarity; ecosystem function; functional groups; leaf economics spectrum; nitrogen fixation; quadratic entropy
Abstract The elucidation of relationships between biodiversity and ecosystem processes has been limited by the definition of metrics of biodiversity and their integration into experimental design. Functional trait screening can strengthen the performance of these designs. We suggest the use of Rao's quadratic entropy to measure both functional diversity and phylogenetic diversity of species mixtures proposed for an experimental design, and demonstrate how they can provide complementary information. We also present an index assessing the statistical performance of these independent variables in different experimental designs. Measurement of independent variables as continuous vs. discrete variables reduces statistical performance, but improves the model by quantifying species differences masked by group assignments. To illustrate these advances, we present an example from a tropical forest tree community in which we screened 38 species for nine functional traits. The proposed TropiDEP design is based on the relative orthogonality of two multivariate trait axes defined using principal component analysis. We propose that independent variables describing functional diversity might be grouped to calculate independent variables describing suites of different traits with potentially different effects on particular ecosystem processes. In other systems these axes may differ from those reported here, yet the methods of analysis integrating functional and phylogenetic diversity into experimental design could be universal.
Address [Baraloto, Christopher; Roggy, Jean-Christophe] INRA, UMR Ecol Forets Guyane, Kourou, French Guiana, Email: chris.baraloto@ecofog.gf
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 ISI:000276507800004 Approved no
Call Number (up) EcoFoG @ eric.marcon @ Serial 62
Permanent link to this record