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Author Marcon, E.; Puech, F. openurl 
  Title Evaluating the geographic concentration of industries using distance-based methods Type Journal Article
  Year 2003 Publication Journal of Economic Geography Abbreviated Journal J. Econ. Geogr.  
  Volume 3 Issue 4 Pages 409-428  
  Keywords agglomeration; clustering; geographic concentration; location of firms  
  Abstract (down) We propose new methods for evaluating the spatial distribution of firms. To assess whether firms are concentrated or dispersed, economists have traditionally used indices that analyse the heterogeneity of a spatial structure at a single geographic level. We introduce distance-based methods, Besag's L function (derived from Ripley's K function) and Diggle and Chetwynd's D function to describe simultaneously spatial distribution at different geographical scales. Our empirical applications consider the distribution of French manufacturing firms in the Paris area and in France generally. For some geographic levels, results show significant concentration or dispersion of firms according to their sector of activity.  
  Address ENGREF, Kourou 97310, French Guiana  
  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 1468-2702 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000185742500004 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 269  
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Author Lebrini, M.; Mbomekallé, I.M.; Dolbecq, A.; Marrot, J.; Berthet, P.; Ntienoue, J.; Sécheresse, F.; Vigneron, J.; Etcheberry, A. url  openurl
  Title Manganese(III)-containing wells-dawson sandwich-type polyoxometalates: Comparison with their manganese(II) counterparts Type Journal Article
  Year 2011 Publication Inorganic Chemistry Abbreviated Journal Inorg. Chem.  
  Volume 50 Issue 14 Pages 6437-6448  
  Keywords  
  Abstract (down) We present the synthesis and structural characterization, assessed by various techniques (FTIR, TGA, UV-vis, elemental analysis, single-crystal X-ray diffraction for three compounds, magnetic susceptibility, and electrochemistry) of five manganese-containing Wells-Dawson sandwich-type (WDST) complexes. The dimanganese(II)-containing complex, [Na2(H2O) 2MnII2(As2W15O 56)2]18- (1), was obtained by reaction of MnCl2 with 1 equiv of [As2W15O 56]12- in acetate medium (pH 4.7). Oxidation of 1 by Na2S2O8 in aqueous solution led to the dimanganese(III) complex [Na2(H2O)2Mn III2(As2W15O56) 2]16- (2), while its trimanganese(II) homologue, [Na(H2O)2MnII(H2O)Mn II2(As2W15O56) 2]17- (3), was obtained by addition of ca. 1 equiv of MnCl2 to a solution of 1 in 1 M NaCl. The trimanganese(III) and tetramanganese(III) counterparts, [MnIII(H2O)Mn III2(As2W15O56) 2]15- (4) and [MnIII2(H 2O)2MnIII2(As2W 15O56)2]12- (6), are, respectively, obtained by oxidation of aqueous solutions of 3 and [MnII2(H2O)2MnII2(As 2W15O56)2]16- (5) by Na2S2O8. Single-crystal X-ray analyses were carried out on 2, 3, and 4. BVS calculations and XPS confirmed that the oxidation state of Mn centers is +II for complexes 1, 3, and 5 and +III for 2, 4, and 6. A complete comparative electrochemical study was carried out on the six compounds cited above, and it was possible to observe the distinct redox steps MnIV/III and MnIII/II. Magnetization measurements, as a function of temperature, confirm the presence of antiferromagnetic interactions between the Mn ions in these compounds in all cases with the exception of compound 2. © 2011 American Chemical Society.  
  Address Laboratoire de Physico-Chimie de L'Etat Solide, ICMMO, Université Paris-Sud, Bâtiment 410, 91405 Orsay Cedex, France  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 00201669 (Issn) ISBN Medium  
  Area Expedition Conference  
  Notes Export Date: 21 October 2011; Source: Scopus; Coden: Inoca; doi: 10.1021/ic102237x; Language of Original Document: English; Correspondence Address: Mbomekallé, I.M.; Institut Lavoisier de Versailles, UMR 8180, CNRS Université de Versailles Saint-Quentin, 45 Avenue des Etats-Unis, 78035 Versailles Cedex, France; email: israel.mbomekalle@chimie.uvsq.fr Approved no  
  Call Number EcoFoG @ webmaster @ Serial 346  
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Author Ollivier, M.; Baraloto, C.; Marcon, E. openurl 
  Title A trait database for Guianan rain forest trees permits intra- and inter-specific contrasts Type Journal Article
  Year 2007 Publication Annals of Forest Science Abbreviated Journal Ann. For. Sci.  
  Volume 64 Issue 7 Pages 781-786  
  Keywords plant traits; tropical forest; French Guiana; functional groups; plasticity; ontogeny  
  Abstract (down) We present a plant trait database covering autecology for rain forest trees of French Guiana. The database comprises more than thirty traits including autecology (e. g., habitat associations and reproductive phenology), wood structure (e. g., density and tension characteristics) and physiology at the whole plant (e. g., carbon and nitrogen isotopes) and leaf level (e. g., specific leaf area, photosynthetic capacity). The current database describes traits for about nine hundred species from three hundred genera in one hundred families. For more than sixty species, data on twelve morphological and ecophysiological traits are provided for individual plants under different environmental conditions and at different ontogenetic stages. The database is thus unique in permitting intraspecific analyses, such as the effects of ontogenetic stages or environmental conditions on trait values and their relationships.  
  Address INRA, Unit Mixte Rech Ecol Forets Guyane, Kourou, France, Email: baraloto.c@kourou.cirad.fr  
  Corporate Author Thesis  
  Publisher EDP SCIENCES S A Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1286-4560 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000250097700011 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 158  
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Author Vincent, G.; Sabatier, D.; Blanc, L.; Chave, J.; Weissenbacher, E.; Pélissier, R.; Fonty, E.; Molino, J.-F.; Couteron, P. url  openurl
  Title Accuracy of small footprint airborne LiDAR in its predictions of tropical moist forest stand structure Type Journal Article
  Year 2012 Publication Remote Sensing of Environment Abbreviated Journal Remote Sens. Environ.  
  Volume 125 Issue Pages 23-33  
  Keywords Basal area; Lidar; Tropical moist forest  
  Abstract (down) We predict stand basal area (BA) from small footprint LiDAR data in 129 one-ha tropical forest plots across four sites in French Guiana and encompassing a great diversity of forest structures resulting from natural (soil and geological substrate) and anthropogenic effects (unlogged and logged forests). We use predictors extracted from the Canopy Height Model to compare models of varying complexity: single or multiple regressions and nested models that predict BA by independent estimates of stem density and quadratic mean diameter. Direct multiple regression was the most accurate, giving a 9.6% Root Mean Squared Error of Prediction (RMSEP). The magnitude of the various errors introduced during the data collection stage is evaluated and their contribution to MSEP is analyzed. It was found that these errors accounted for less than 10% of model MSEP, suggesting that there is considerable scope for model improvement. Although site-specific models showed lower MSEP than global models, stratification by site may not be the optimal solution. The key to future improvement would appear to lie in a stratification that captures variations in relations between LiDAR and forest structure. © 2012 Elsevier Inc.  
  Address ONF, Direction régionale de la Guyane, Cayenne, 97300 France  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 00344257 (Issn) ISBN Medium  
  Area Expedition Conference  
  Notes Export Date: 9 August 2012; Source: Scopus; Article in Press; Coden: Rseea; doi: 10.1016/j.rse.2012.06.019; Language of Original Document: English; Correspondence Address: Vincent, G.; IRD AMAP CIRAD, TA A-51/PS2, 34398 Montpellier cedex 5, Franceemail: gregoire.vincent@ird.fr Approved no  
  Call Number EcoFoG @ webmaster @ Serial 418  
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Author Soong, J.L.; Janssens, I.A.; Grau, O.; Margalef, O.; Stahl, C.; Van Langenhove, L.; Urbina, I.; Chave, J.; Dourdain, A.; Ferry, B.; Freycon, V.; Herault, B.; Sardans, J.; Peñuelas, J.; Verbruggen, E. url  doi
openurl 
  Title Soil properties explain tree growth and mortality, but not biomass, across phosphorus-depleted tropical forests Type Journal Article
  Year 2020 Publication Scientific reports Abbreviated Journal Sci Rep  
  Volume 10 Issue 2302 Pages  
  Keywords  
  Abstract (down) We observed strong positive relationships between soil properties and forest dynamics of growth and mortality across twelve primary lowland tropical forests in a phosphorus-poor region of the Guiana Shield. Average tree growth (diameter at breast height) increased from 0.81 to 2.1 mm yr-1 along a soil texture gradient from 0 to 67% clay, and increasing metal-oxide content. Soil organic carbon stocks in the top 30 cm ranged from 30 to 118 tons C ha-1, phosphorus content ranged from 7 to 600 mg kg-1 soil, and the relative abundance of arbuscular mycorrhizal fungi ranged from 0 to 50%, all positively correlating with soil clay, and iron and aluminum oxide and hydroxide content. In contrast, already low extractable phosphorus (Bray P) content decreased from 4.4 to <0.02 mg kg-1 in soil with increasing clay content. A greater prevalence of arbuscular mycorrhizal fungi in more clayey forests that had higher tree growth and mortality, but not biomass, indicates that despite the greater investment in nutrient uptake required, soils with higher clay content may actually serve to sustain high tree growth in tropical forests by avoiding phosphorus losses from the ecosystem. Our study demonstrates how variation in soil properties that retain carbon and nutrients can help to explain variation in tropical forest growth and mortality, but not biomass, by requiring niche specialization and contributing to biogeochemical diversification across this region.  
  Address Institut National Polytechnique Félix Houphouët-Boigny, Ivory CoastYamoussoukro, Cote d'Ivoire  
  Corporate Author Thesis  
  Publisher NLM (Medline) Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 20452322 (Issn) ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number EcoFoG @ webmaster @ Serial 916  
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Author Baraloto, C.; Morneau, F.; Bonal, D.; Blanc, L.; Ferry, B. openurl 
  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 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 (down) 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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Author Baraloto, C.; Goldberg, D.E.; Bonal, D. openurl 
  Title Performance trade-offs among tropical tree seedlings in contrasting microhabitats Type Journal Article
  Year 2005 Publication Ecology Abbreviated Journal Ecology  
  Volume 86 Issue 9 Pages 2461-2472  
  Keywords canopy gaps; French Guiana; regeneration niche; relative growth rate; seed size; shade tolerance; soil moisture; tropical forest  
  Abstract (down) We investigated performance trade-offs among seedlings of nine tropical tree species during a -five-year field experiment. Seedlings were grown in eight microhabitat types composed of paired gap and shaded understory sites in each of four soil types. We defined performance trade-offs relevant to coexistence as significant pairwise rank reversals for species performance between contrasting situations, of which we characterize three types: microhabitat, fitness component, and ontogenetic. Only 2 of 36 species pairs exhibited microhabitat trade-offs or reversed rankings for survival or relative growth rate (RGR) among microhabitats, and only one species pair reversed performance ranks among soil types. We found stronger evidence for rank reversals between fitness components (survival and RGR), particularly in gap vs. understory environments, suggesting a general trade-off between shade tolerance (survival in shade) and gap establishment (RGR in gaps). Third, the most frequent rank reversals between species pairs occurred between early and later ontogenetic stages, especially between fitness components in contrasting microhabitats. Overall, 15 of 36 pairs of potentially competing species exhibited some type of seedling performance trade-off, two species pairs never outperformed one another, and for 19 species pairs one species was a consistent better performer. We suggest that ontogenetic trade-offs, in concert with microhabitat and fitness component trade-offs, may contribute to species coexistence of long-lived organisms such as tropical trees.  
  Address Univ Michigan, Dept Ecol & Evolutionary Biol, Ann Arbor, MI 48109 USA, Email: baraloto.c@kourou.cirad.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:000231373600021 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 252  
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Author Masse, P.S.M.; Kenne, M.; Mony, R.; Dejean, A.; Tindo, M. openurl 
  Title Initial behavior in colony fragments of an introduced population of the invasive ant Wasmannia auropunctata Type Journal Article
  Year 2011 Publication Comptes Rendus Biologies Abbreviated Journal C. R. Biol.  
  Volume 334 Issue 7 Pages 572-576  
  Keywords Aggregation; Death feigning; Thanatosis; Worker transportation; Biological invasion; Little fire ant  
  Abstract (down) We investigated in the laboratory the initial behavior of propagules of the invasive ant Wasmannia auropunctata in Cameroon where it has been introduced. Both workers and queens at first feigned death (thanatosis), and then the workers slowly moved around the experimental arena; the queens did the same about 10 seconds later. Each queen antennated selected workers that then aggregated together by grasping the hind leg of another ant with their mandibles. When encountering the queen again, the lead worker climbed up the queen's hind leg and onto her back, followed by some other individuals. The remaining workers followed the queen to a location in the experimental arena. When brood was present, the workers transferred it to this location. Orphaned workers did not aggregate, but gathered the brood together and took care of it. By permitting propagules to survive, these behaviors likely contribute to the success of W. auropunctata as an invader. (C) 2011 Academie des sciences. Published by Elsevier Masson SAS. All rights reserved.  
  Address [Kenne, M; Mony, R; Tindo, M] Univ Douala, Fac Sci, Dept Biol Organismes Anim, Douala, Cameroon, Email: tindodouala@yahoo.com  
  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 WOS:000293673300010 Approved no  
  Call Number EcoFoG @ webmaster @ Serial 332  
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Author Caron, H.; Molino, J.-F.; Sabatier, D.; Léger, P.; Chaumeil, P.; Scotti-Saintagne, C.; Frigério, J.-M.; Scotti, I.; Franc, A.; Petit, R.J. pdf  url
doi  openurl
  Title Chloroplast DNA variation in a hyperdiverse tropical tree community Type Journal Article
  Year 2019 Publication Ecology and Evolution Abbreviated Journal Ecology and Evolution  
  Volume 9 Issue 8 Pages 4897-4905  
  Keywords chloroplast DNA; DNA barcoding; genetic diversity; hybridization; incomplete lineage sorting; introgression; species diversity; tropical trees  
  Abstract (down) We investigate chloroplast DNA variation in a hyperdiverse community of tropical rainforest trees in French Guiana, focusing on patterns of intraspecific and interspecific variation. We test whether a species genetic diversity is higher when it has congeners in the community with which it can exchange genes and if shared haplotypes are more frequent in genetically diverse species, as expected in the presence of introgression. We sampled a total of 1,681 individual trees from 472 species corresponding to 198 genera and sequenced them at a noncoding chloroplast DNA fragment. Polymorphism was more frequent in species that have congeneric species in the study site than in those without congeners (30% vs. 12%). Moreover, more chloroplast haplotypes were shared with congeners in polymorphic species than in monomorphic ones (44% vs. 28%). Despite large heterogeneities caused by genus-specific behaviors in patterns of hybridization, these results suggest that the higher polymorphism in the presence of congeners is caused by local introgression rather than by incomplete lineage sorting. Our findings suggest that introgression has the potential to drive intraspecific genetic diversity in species-rich tropical forests.  
  Address INRA, UR629 Ecologie des Forêts Méditerranéennes, URFM, Avignon, France  
  Corporate Author Thesis  
  Publisher John Wiley and Sons Ltd Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 20457758 (Issn) ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number EcoFoG @ webmaster @ Serial 870  
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Author Marcon, E.; Puech, F.; Traissac, S. pdf  url
openurl 
  Title Characterizing the relative spatial structure of point patterns Type Journal Article
  Year 2012 Publication International Journal of Ecology Abbreviated Journal Int. J. Ecol.  
  Volume 2012 Issue Article ID 619281 Pages 11  
  Keywords  
  Abstract (down) We generalize Ripley's K function to get a new function, M, to characterize the spatial structure of a point pattern relatively to another one. We show that this new approach is pertinent in ecology when space is not homogenous and the size of objects matters. We present how to use the function and test the data against the null hypothesis of independence between points. In a tropical tree data set we detect intraspecific aggregation and interspecific competition. © 2012 Eric Marcon et al.  
  Address LET (Université de Lyon, CNRS, ENTPE), Institut des Sciences de l'Homme, 14 avenue Berthelot, 69363 Lyon Cedex 07, France  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 16879708 (Issn) ISBN Medium  
  Area Expedition Conference  
  Notes Export Date: 7 November 2012; Source: Scopus; Art. No.: 619281; doi: 10.1155/2012/619281; Language of Original Document: English; Correspondence Address: Marcon, E.; AgroParisTech, UMR EcoFoG, BP 709, 97310 Kourou, French Guiana; email: eric.marcon@ecofog.gf Approved no  
  Call Number EcoFoG @ webmaster @ Serial 446  
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