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Author Gond, V.; Guitet, S.
Title Remote Sensing in Post-Logging Diagnoses for Forest Management in French Guiana Type Journal Article
Year 2009 Publication Bois et Forets des Tropiques Abbreviated Journal Bois For. Trop.
Volume 63 Issue 299 Pages 5-13
Keywords selective logging; logging impact inspections; French Guiana; remote sensing; forest management
Abstract This study is part of the activities carried out to monitor tow-impact logging operations in humid tropical forests. The sustainability of these activities is highly dependent on the scale of logging damage, and managers therefore need to carry out effective checks on the quality of forestry work. In this study, remote sensing was used to track the extension of logging operations and to assess damage, through images acquired during and after logging in each parcel. Analysis of the high-resolution images (10 m) clearly identifies logged-over clearings and some skidding tracks, allowing assessments of gaps opening up in the canopy. Several parcels were monitored in this French Guiana study. A simple diagnostic procedure was established for each parcel to assess logging intensity and identify new logging tracks and timber losses. The remote sensing toot thus helps to make more accurate assessments of logging quality and to draw relevant conclusions for the logging company. The study has demonstrated the usefulness of remote sensing to identify damage after logging. The quality of restitution of the damage was validated by means of a database on the logging terrain and through field missions. This post-logging inspection tool can now be automated for fully operational use by forest managers.
Address [Gond, Valery] Univ Laval, Fac Foresterie, Umr Ecofog Guyane francaise, Cirad,UR 36, Quebec City, PQ G1V OA6, Canada
Corporate Author Thesis
Publisher CIRAD-CENTRE COOPERATION INT RECHERCHE AGRONOMIQUE POUR Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0006-579X ISBN Medium
Area Expedition Conference
Notes (up) ISI:000266156700001 Approved no
Call Number EcoFoG @ webmaster @ Serial 280
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Author Herault, B.; Thoen, D.
Title How habitat area, local and regional factors shape plant assemblages in isolated closed depressions Type Journal Article
Year 2009 Publication Acta Oecologica-International Journal of Ecology Abbreviated Journal Acta Oecol.-Int. J. Ecol.
Volume 35 Issue 3 Pages 385-392
Keywords Closed depressions; Colonization; Connectivity; Fragmented habitats; Emergent Groups; Open and forested landscape; Life-history traits
Abstract Classifying species by shared life-history traits is important if common ecological response groups are to be identified among different species. We investigated how habitat area, local and regional factors shape plant communities in small isolated closed depressions, and how the species richness is related to the interplay between environmental factors and specific life-history trait combinations. In Central-Western Europe, 169 closed depressions were completely Surveyed for plant presence in two highly contrasted landscapes (forested and open landscapes). All species were clustered into 9 Emergent Groups based oil 10 life-history traits related to plant dispersal, establishment and persistence. Habitat areas were related to species presence using logistic regressions. Most Emergent Groups were more area-dependent in open than in forested landscapes, owing to heterogeneous light levels in forest weakening the species-area relationship. In open landscapes, Floating Hydrophytes were severely underrepresented in very small depressions, owing to the absence of waterfowl poulation. Local environmental and regional factors were related to species richness using Generalized Linear Models. In open landscapes, local environmental factors such as water conductivity or soil productivity are respectively the main predictors. In forested landscapes, the abundance of most Emergent Groups Was better predicted by regional factors, i.e., habitat connectivity and distance to the forest edge. Forested landscapes strongly impeded the closed depressions' colonization by the less mobile Emergent Groups Such as Large-seeded Perennials. (C) 2009 Elsevier Masson SAS. All rights reserved.
Address [Herault, Bruno] Univ Antilles Guyane, UMR EcoFoG, F-97387 Kourou, France, Email: bruno.herault@ecofog.gf
Corporate Author Thesis
Publisher GAUTHIER-VILLARS/EDITIONS ELSEVIER Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1146-609X ISBN Medium
Area Expedition Conference
Notes (up) ISI:000266174400006 Approved no
Call Number EcoFoG @ eric.marcon @ Serial 112
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Author Delabie, J.H.C.; Cereghino, R.; Groc, S.; Dejean, A.; Gibernau, M.; Corbara, B.; Dejean, A.
Title Ants as biological indicators of Wayana Amerindian land use in French Guiana Type Journal Article
Year 2009 Publication Comptes Rendus Biologies Abbreviated Journal C. R. Biol.
Volume 332 Issue 7 Pages 673-684
Keywords Landscape ecology; Traditional land use; Formicidae; Rapid assessment; Pit-fall traps; Self-Organizing Maps
Abstract We examined the ecological impact of traditional land use by Wayana Amerindians in French Guiana using ants as bio-indicators. Ants were sampled through a rapid assessment method and the core results analyzed using Kohonen's self-organizing maps (SOM). Our sample sites included: (1) a Wayana village; (2) a cassava plantation; (3) an abandoned cassava plantation; (4) a forest fragment near the village; (5) a riparian forest; and (6) a primary terra firma forest. The ant diversity decreases according to the decree to which the habitat is disturbed. The SOM allowed us to compare the ecological succession between the six habitats. The protocol used is robust since the same conclusions were drawn using partial data. To cite this article: J.H.C Delabie et al., C R. Biologies 332 (2009). (C) 2009 Academie des sciences. Published by Elsevier Masson SAS. All rights reserved.
Address [Groc, Sarah; Dejean, Andrea; Dejean, Alain] CNRS, UMR 8172, F-97379 Kourou, France, Email: alain.dejean@wanadoo.fr
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 (up) ISI:000267243700009 Approved no
Call Number EcoFoG @ eric.marcon @ Serial 109
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Author Flores, O.; Rossi, V.; Mortier, F.
Title Autocorrelation offsets zero-inflation in models of tropical saplings density Type Journal Article
Year 2009 Publication Ecological Modelling Abbreviated Journal Ecol. Model.
Volume 220 Issue 15 Pages 1797-1809
Keywords Hierarchical Bayesian Modelling; Conditional Auto-Regressive model; Variable selection; Zero-Inflated Poisson; Posterior predictive; Paracou; French Guiana
Abstract Modelling the local density of tropical saplings can provide insights into the ecological processes that drive species regeneration and thereby help predict population recovery after disturbance. Yet, few studies have addressed the challenging issues in autocorrelation and zero-inflation of local density. This paper presents Hierarchical Bayesian Modelling (HBM) of sapling density that includes these two features. Special attention is devoted to variable selection, model estimation and comparison. We developed a Zero-Inflated Poisson (ZIP) model with a latent correlated spatial structure and compared it with non-spatial ZIP and Poisson models that were either autocorrelated (Spatial Generalized Linear Mixed, SGLM) or not (generalized linear models, GLM). In our spatial models, local density autocorrelation was modeled by a Conditional Auto-Regressive (CAR) process. 13 explicative variables described ecological conditions with respect to topography, disturbance, stand structure and intraspecific processes. Models were applied to six tropical tree species with differing biological attributes: Oxandra asbeckii, Eperua falcata, Eperua grandiflora, Dicorynia guianensis, Qualea rosea, and Tachigali melinonii. We built species-specific models using a simple method of variable selection based on a latent binary indicator. Our spatial models showed a close correlation between observed and estimated densities with site spatial structure being correctly reproduced. By contrast, the non-spatial models showed poor fits. Variable selection highlighted species-specific requirements and susceptibility to local conditions. Model comparison overall showed that the SGLM was the most accurate explanatory and predictive model. Surprisingly, zero-inflated models performed less well. Although the SZIP model was relevant with respect to data distribution, and more flexible with respect to response curves, its model complexity caused marked variability in parameter estimates. In the SUM, the spatial process alone accounted for zero-inflation in the data. A refinement of the hypotheses employed at the process level could compensate for distribution flaws at the data level. This study emphasized the importance of the HBM framework in improving the modelling of density-environment relationships. (C) 2008 Elsevier B.V. All rights reserved.
Address [Flores, O.] CNRS, Ctr Ecol Fonct & Evolut, UMR 5175, F-34293 Montpellier 5, France, Email: olivierflores@free.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 (up) ISI:000267585400007 Approved no
Call Number EcoFoG @ eric.marcon @ Serial 201
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Author Vedel, V.; Brena, C.; Arthur, W.
Title Demonstration of a heritable component of the variation in segment number in the centipede Strigamia maritima Type Journal Article
Year 2009 Publication Evolution & Development Abbreviated Journal Evol. Dev.
Volume 11 Issue 4 Pages 434-440
Keywords
Abstract Here we address the question of how arthropod segment number may evolve by reporting the results of further work on the model system Strigamia maritima. Recently, we showed that there was a plastic component of the variation in segment number within this species; now we demonstrate that there is also a heritable component. This is important because it enables a connection to be made between the known latitudinal trend among species of geophilomorph centipedes ( more segments at lower latitudes) and the parallel trend within them. This latter trend is best documented in S. maritima but is also known in several other species. However, while a general connection between the inter- and intraspecific trends can now be made, deciding upon a specific hypothesis of the nature of the selection involved is still problematic. We provide two alternative hypotheses, one based on the temperature-related plasticity in segment number being adaptive, the other based on it being nonadaptive.
Address [Vedel, Vincent; Arthur, Wallace] Natl Univ Ireland, Dept Zool, Sch Nat Sci, Galway, Ireland, Email: wallace.arthur@nuigalway.ie
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 1520-541X ISBN Medium
Area Expedition Conference
Notes (up) ISI:000267659600011 Approved no
Call Number EcoFoG @ eric.marcon @ Serial 200
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Author Orivel, J.; Grangier, J.; Foucaud, J.; Le Breton, J.; Andres, F.X.; Jourdan, H.; Delabie, J.H.C.; Fournier, D.; Cerdan, P.; Facon, B.; Estoup, A.; Dejean, A.
Title Ecologically heterogeneous populations of the invasive ant Wasmannia auropunctata within its native and introduced ranges Type Journal Article
Year 2009 Publication Ecological Entomology Abbreviated Journal Ecol. Entomol.
Volume 34 Issue 4 Pages 504-512
Keywords Biological invasion; disturbance; ecological traits; native; Wasmannia auropunctata
Abstract 1. The biology of most invasive species in their native geographical areas remains largely unknown. Such studies are, however, crucial in shedding light on the ecological and evolutionary processes underlying biological invasions. 2. The present study focuses on the little fire ant Wasmannia auropunctata, a species native to Central and South America that has been widely introduced and which has become invasive throughout the tropics. We characterise and compare several ecological traits of native populations in French Guiana with those in one of its introduced ranges, New Caledonia. 3. We found ecologically heterogeneous populations of W. auropunctata coexisting in the species' native geographical area. First, we found populations restricted to naturally perturbed areas (particularly floodplains) within the primary forest, and absent from the surrounding forest areas. These populations were characterised by low nest and worker densities. Second, we found dominant populations in recent anthropogenic areas (e.g. secondary forest or forest edge along road) characterised by high nest and worker densities, and associated with low ant species richness. The local dominance of W. auropunctata in such areas can be due to the displacement of other species (cause) or the filling-up of empty habitats unsuitable to other ants (effect). With respect to their demographic features and ant species richness, the populations of native anthropogenic habitats were to a large extent similar to the invasive populations introduced into remote areas. 4. The results point to the need for greater research efforts to better understand the ecological and demographic features of invasive species within their native ranges.
Address [Orivel, Jerome; Grangier, Julien; Le Breton, Julien] Univ Toulouse 3, Lab Evolut & Divers Biol, CNRS, UMR 5174, F-31062 Toulouse 9, 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 0307-6946 ISBN Medium
Area Expedition Conference
Notes (up) ISI:000267659900010 Approved no
Call Number EcoFoG @ eric.marcon @ Serial 202
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Author Groc, S.; Orivel, J.; Dejean, A.; Martin, J.M.; Etienne, M.P.; Corbara, B.; Delabie, J.H.C.
Title Baseline study of the leaf-litter ant fauna in a French Guianese forest Type Journal Article
Year 2009 Publication Insect Conservation and Diversity Abbreviated Journal Insect. Conserv. Divers.
Volume 2 Issue 3 Pages 183-193
Keywords Ants of the Leaf Litter Protocol; baseline study; leaf-litter ants; Nouragues; Winkler method
Abstract 1. Leaf-litter ants represent a major component of biodiversity and are excellent bioindicators reflecting the health of terrestrial ecosystems. This study, conducted in an unspoiled forest near the Nouragues Research Station, represents the first inventory of leaf-litter ant diversity conducted in French Guiana, and so can be considered as the baseline dataset for ants in this country. 2. Ants were extracted from the leaf-litter using the Ants of the Leaf Litter Protocol, along an altitudinal gradient at four forest sites, including an inselberg. 3. A total of 196 ant species representing 46 genera distributed over eight subfamilies were collected. Four distinct communities spread over a gradient of diversity were thus identified: the liana forest was the most species-rich (140 species) followed by the forested plateau (102 species), the transition forest (87 species) and the forest at the top of the inselberg (71 species). 4. The discovery of species new to science plus several species recorded for the first time in French Guiana, coupled with the particular context of this area, suggests that the Nouragues Research Station might represent a centre of endemism. Once completed, this leaf-litter ant dataset will contribute greatly to the knowledge of ant biodiversity in French Guiana, and has the potential to progressively become an indispensable tool for country-wide conservation planning programmes.
Address [Groc, Sarah; Dejean, Alain; Martin, Jean-Michel] CNRS, Ecol Forets Guyane UMR 8172, Kourou, France, Email: sarah.groc@ecofog.gf
Corporate Author Thesis
Publisher WILEY-LISS Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1752-458X ISBN Medium
Area Expedition Conference
Notes (up) ISI:000268269400004 Approved no
Call Number EcoFoG @ eric.marcon @ Serial 108
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Author Chang, S.S.; Clair, B.; Ruelle, J.; Beauchene, J.; Di Renzo, F.; Quignard, F.; Zhao, G.J.; Yamamoto, H.; Gril, J.
Title Mesoporosity as a new parameter for understanding tension stress generation in trees Type Journal Article
Year 2009 Publication Journal of Experimental Botany Abbreviated Journal J. Exp. Bot.
Volume 60 Issue 11 Pages 3023-3030
Keywords Growth stress; hydrogel; mesoporosity; tension wood
Abstract The mechanism for tree orientation in angiosperms is based on the production of high tensile stress on the upper side of the inclined axis. In many species, the stress level is strongly related to the presence of a peculiar layer, called the G-layer, in the fibre cell wall. The structure of the G-layer has recently been described as a hydrogel thanks to N-2 adsorption-desorption isotherms of supercritically dried samples showing a high mesoporosity (pores size from 2-50 nm). This led us to revisit the concept of the G-layer that had been, until now, only described from anatomical observation. Adsorption isotherms of both normal wood and tension wood have been measured on six tropical species. Measurements show that mesoporosity is high in tension wood with a typical thick G-layer while it is much less with a thinner G-layer, sometimes no more than normal wood. The mesoporosity of tension wood species without a G-layer is as low as in normal wood. Not depending on the amount of pores, the pore size distribution is always centred around 6-12 nm. These results suggest that, among species producing fibres with a G-layer, large structural differences of the G-layer exist between species.
Address [Chang, Shan-Shan; Clair, Bruno; Gril, Joseph] Univ Montpellier 2, LMGC, CNRS, F-34095 Montpellier 5, France, Email: clair@lmgc.univ-montp2.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 0022-0957 ISBN Medium
Area Expedition Conference
Notes (up) ISI:000268588300008 Approved no
Call Number EcoFoG @ eric.marcon @ Serial 107
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Author Leroy, C.; Corbara, B.; Dejean, A.; Cereghino, R.
Title Ants mediate foliar structure and nitrogen acquisition in a tank-bromeliad Type Journal Article
Year 2009 Publication New Phytologist Abbreviated Journal New Phytol.
Volume 183 Issue 4 Pages 1124-1133
Keywords Aechmea mertensii; antgardens; Camponotus femoratus; foliar structure; delta N-15; Pachycondyla goeldii; phytotelmata contents
Abstract Aechmea mertensii is a tank-bromeliad that roots on ant-gardens initiated by the ants Camponotus femoratus and Pachycondyla goeldii. Its leaves form compartments acting as phytotelmata that hold rainwater and provide habitats for invertebrates. In this article, we aimed to determine whether the association with either C. femoratus or P. goeldii influenced the vegetative traits of A. mertensii, invertebrate diversity and nutrient assimilation by the leaves. Transmitted light, vegetative traits and phytotelmata contents were compared between the two A. mertensii ant-gardens. Camponotus femoratus colonized partially shaded areas, whereas P. goeldii colonized exposed areas. The bromeliads' rosettes had a large canopy (C. femoratus ant-gardens), or were smaller and amphora shaped (P. goeldii ant-gardens). There were significant differences in leaf anatomy, as shaded leaves were thicker than exposed leaves. The mean volumes of water, fine particulate organic matter and detritus in C. femoratus-associated bromeliads were three to five times higher than in P. goeldii-associated bromeliads. Moreover, the highest invertebrate diversity and leaf delta N-15 values were found in C. femoratus-associated bromeliads. This study enhances our understanding of the dynamics of biodiversity, and shows how ant-plant interactions can have trophic consequences and thus influence the architecture of the interacting plant via a complex feedback loop.
Address [Leroy, Celine; Dejean, Alain] EcoFoG, CNRS, UMR 8172, F-97379 Kourou, France, Email: Celine.Leroy@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 0028-646X ISBN Medium
Area Expedition Conference
Notes (up) ISI:000268855300020 Approved no
Call Number EcoFoG @ eric.marcon @ Serial 106
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Author Leroy, C.; Sabatier, S.; Wahyuni, N.S.; Barczi, J.F.; Dauzat, J.; Laurans, M.; Auclair, D.
Title Virtual trees and light capture: a method for optimizing agroforestry stand design Type Journal Article
Year 2009 Publication Agroforestry Systems Abbreviated Journal Agrofor. Syst.
Volume 77 Issue 1 Pages 37-47
Keywords Acacia mangium; Tectona grandis; Agroforestry; Light interception; Plant architecture; Simulation; 3D virtual plant
Abstract In agroforestry systems, the distribution of light transmitted under tree canopies can be a limiting factor for the development of intercrops. The light available for intercrops depends on the quantity of light intercepted by tree canopies and, consequently, on the architecture of the tree species present. The influence of tree architecture on light transmission was analysed using dynamic 3D architectural models. The architectural analysis of Acacia mangium and Tectona grandis was performed in Indonesian agroforestry systems with trees aged from 1 to 3 years. 3D virtual trees were then generated with the AmapSim simulation software and 3D virtual experiments in which tree age, planting density, planting pattern and pruning intensity varied were reconstructed in order to simulate light available for the crop. Canopy closure of trees was more rapid in A. mangium than in T. grandis agroforestry systems; after 3 years the quantity of light available for A. mangium intercrops was three times lower than under T. grandis. Simulations with A. mangium showed that practices such as pruning and widening tree spacing enable to increase the total transmitted light within the stand. On T. grandis, modification of the tree row azimuth resulted in changes in the spatial and seasonal distribution of light available for the intercrops. These results are discussed in terms of agroforestry system management.
Address [Sabatier, Sylvie; Barczi, Jean-Francois; Dauzat, Jean; Laurans, Marilyne] CIRAD, UMR AMAP Botan & Bioinformat Architecture Plantes, 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 0167-4366 ISBN Medium
Area Expedition Conference
Notes (up) ISI:000268865600004 Approved no
Call Number EcoFoG @ eric.marcon @ Serial 199
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