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Lebrini, M.; Robert, F.; Vezin, H.; Roos, C. |
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Title |
Electrochemical and quantum chemical studies of some indole derivatives as corrosion inhibitors for C38 steel in molar hydrochloric acid |
Type |
Journal Article |
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Year |
2010 |
Publication |
Corrosion Science |
Abbreviated Journal |
Corrosion Sci. |
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Volume |
52 |
Issue |
10 |
Pages |
3367-3376 |
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Keywords |
Steel; EIS; Raman spectroscopy; Polarization; Acid inhibition |
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Abstract |
A comparative study of 9H-pyrido[3,4-b]indole (norharmane) and 1-methyl-9H-pyrido[3,4-b]indole (harmane) as inhibitors for C38 steel corrosion in 1 M HCl solution at 25 degrees C was carried out. Potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) techniques were applied to study the metal corrosion behavior in the absence and presence of different concentrations of these inhibitors. The OCP as a function of time were also established. Cathodic and anodic polarization curves show that norharmane and harmane are a mixed-type inhibitors. Adsorption of indole derivatives on the C38 steel surface, in 1 M HCl solution, follows the Langmuir adsorption isotherm model. The Delta G degrees(ads) values were calculated and discussed. The potential of zero charge (PZC) of the C38 steel in inhibited solution was studied by the EIS method, and a mechanism for the adsorption process was proposed. Raman spectroscopy confirmed that indole molecules strongly adsorbed onto the steel surface. The electronic properties of indole derivates, obtained using the AM1 semi-empirical quantum chemical approach, were correlated with their experimental efficiencies using the linear resistance model (LR). (C) 2010 Elsevier Ltd. All rights reserved. |
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Address  |
[Robert, F.; Roos, C.] UAG UMR ECOFOG, Lab Mat & Mol Milieu Amazonien, Cayenne 97337, French Guiana, Email: christophe.roos@guyane.univ-ag.fr |
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PERGAMON-ELSEVIER SCIENCE LTD |
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0010-938X |
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ISI:000281315500026 |
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EcoFoG @ eric.marcon @ |
Serial |
44 |
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Author |
Lebrini, M.; Robert, F.; Lecante, A.; Roos, C. |
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Title |
Corrosion inhibition of C38 steel in 1 M hydrochloric acid medium by alkaloids extract from Oxandra asbeckii plant |
Type |
Journal Article |
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Year |
2011 |
Publication |
Corrosion Science |
Abbreviated Journal |
Corrosion Sci. |
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Volume |
53 |
Issue |
2 |
Pages |
687-695 |
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Keywords |
Steel; EIS; Polarization; Raman spectroscopy; Acid inhibition |
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Abstract |
The inhibition effect of alkaloids extract from Oxandra asbeckii plant (OAPE) on the corrosion of C38 steel in 1 M hydrochloric acid solution has been investigated by potentiodynamic polarization and electrochemical impedance spectroscopy (EIS). The corrosion inhibition efficiency increases on increasing plant extracts concentration. Cathodic and anodic polarization curves show that OAPE is a mixed-type inhibitor. The effect of temperature on the corrosion behavior of C38 steel in 1 M HCl with and without addition of plant extract was studied in the temperature range 25-55 degrees C. The thermodynamic functions of dissolution and adsorption processes were calculated from experimental polarization data and the interpretation of the results are given. The adsorption of this plant extract on the C38 steel surface obeys the Langmuir adsorption isotherm. Surface analysis (Raman) was also carried out to establish the corrosion inhibitive property of this plant extract in HCl solution. (C) 2010 Elsevier Ltd. All rights reserved. |
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Address |
[Robert, F.; Lecante, A.; Roos, C.] UAG UMR ECOFOG, Lab Mat & Mol Milieu Amazonien, Cayenne 97337, French Guiana, Email: christophe.roos@guyane.univ-ag.fr |
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Pergamon-Elsevier Science Ltd |
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0010-938x |
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ISI:000287004700021 |
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EcoFoG @ webmaster @ |
Serial |
299 |
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Author |
Rey, O.; Loiseau, A.; Facon, B.; Foucaud, J.; Orivel, J.; Cornuet, J.M.; Robert, S.; Dobigny, G.; Delabie, J.H.C.; Mariano, C.D.F.; Estoup, A. |
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Title |
Meiotic Recombination Dramatically Decreased in Thelytokous Queens of the Little Fire Ant and Their Sexually Produced Workers |
Type |
Journal Article |
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Year |
2011 |
Publication |
Molecular Biology and Evolution |
Abbreviated Journal |
Mol. Biol. Evol. |
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Volume |
28 |
Issue |
9 |
Pages |
2591-2601 |
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Keywords |
parthenogenesis; thelytoky; recombination; inbreeding; biological invasion; Wasmannia auropunctata |
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Abstract |
The little fire ant, Wasmannia auropunctata, displays a peculiar breeding system polymorphism. Classical haplo-diploid sexual reproduction between reproductive individuals occurs in some populations, whereas, in others, queens and males reproduce clonally. Workers are produced sexually and are sterile in both clonal and sexual populations. The evolutionary fate of the clonal lineages depends strongly on the underlying mechanisms allowing reproductive individuals to transmit their genomes to subsequent generations. We used several queen-offspring data sets to estimate the rate of transition from heterozygosity to homozygosity associated with recombination events at 33 microsatellite loci in thelytokous parthenogenetic queen lineages and compared these rates with theoretical expectations under various parthenogenesis mechanisms. We then used sexually produced worker families to define linkage groups for these 33 loci and to compare meiotic recombination rates in sexual and parthenogenetic queens. Our results demonstrate that queens from clonal populations reproduce by automictic parthenogenesis with central fusion. These same parthenogenetic queens produce normally segregating meiotic oocytes for workers, which display much lower rates of recombination (by a factor of 45) than workers produced by sexual queens. These low recombination rates also concern the parthenogenetic production of queen offspring, as indicated by the very low rates of transition from heterozygosity to homozygosity observed (from 0% to 2.8%). We suggest that the combination of automixis with central fusion and a major decrease in recombination rates allows clonal queens to benefit from thelytoky while avoiding the potential inbreeding depression resulting from the loss of heterozygosity during automixis. In sterile workers, the strong decrease of recombination rates may also facilitate the conservation over time of some coadapted allelic interactions within chromosomes that might confer an adaptive advantage in habitats disturbed by human activity, where clonal populations of W. auropunctata are mostly found. |
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[Rey, O; Loiseau, A; Facon, B; Foucaud, J; Cornuet, JM; Robert, S; Dobigny, G] INRA, UMR Ctr Biol Gest Populat INRA IRD CIRAD Montpe, Montferrier Sur Lez, France, Email: olivier.rey@supagro.inra.fr |
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Oxford Univ Press |
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ISSN |
0737-4038 |
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Notes |
WOS:000294552700019 |
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Call Number |
EcoFoG @ webmaster @ |
Serial |
339 |
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Author |
Revel, M.; Dejean, A.; Cereghino, R.; Roux, O. |
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Title |
An Assassin among Predators: The Relationship between Plant-Ants, Their Host Myrmecophytes and the Reduviidae Zelus annulosus |
Type |
Journal Article |
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Year |
2010 |
Publication |
PLoS One |
Abbreviated Journal |
PLoS One |
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Volume |
5 |
Issue |
10 |
Pages |
e13110 |
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Abstract |
Tropical plants frequently live in association with ants that protect their foliage from defoliators. Among them, myrmecophytes have evolved mutualisms with a limited number of plant-ants that they shelter and feed, and, in return, benefit from some protection. Hirtella physophora (Chrysobalanaceae), for example, houses Allomerus decemarticulatus (Myrmicinae) that build gallery-shaped traps to catch large prey. In French Guiana, we frequently observed the assassin bug Zelus annulosus (Reduviidae, Harpactorinae) on the leaves of H. physophora. Here, we studied the distribution of Zelus annulosus among understory plants in the Guianese rainforest and found it only on pubescent plants, including H. Physophora, whether or not it was sheltering an A. decemarticulatus colony, but only rarely on other myrmecophytes. The relationship between Z. annulosus and its host plants is, then, also mutualistic, as the plant trichomes act as an enemy-free space protecting the nymphs from large predatory ants, while the nymphs protect their host-plants from herbivorous insects. Through their relationship with A. decemarticulatus colonies, Z. annulosus individuals are protected from army ants, while furnishing nothing in return. In those cases where H. physophora sheltered both an A. decemarticulatus colony and Z. annulosus nymphs, certain plant individuals repeatedly sheltered nymphs, indicating that female bugs may select not only pubescent plants but also particular H. physophora treelets having characteristics more favourable to the development of their progeny. |
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Address |
[Revel, Messika; Dejean, Alain; Roux, Olivier] Ecofog Ecol Forets Guyane, CNRS, UMR 8172, Kourou, France, Email: olivier.roux@ecofog.gf |
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PUBLIC LIBRARY SCIENCE |
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ISSN |
1932-6203 |
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Notes |
ISI:000282359300014 |
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no |
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Call Number |
EcoFoG @ eric.marcon @ |
Serial |
29 |
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Author |
Quilichini, A.; Macquart, D.; Barabe, D.; Albre, J.; Gibernau, M. |
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Title |
Reproduction of the West Mediterranean endemic Arum pictum (Araceae) on Corsica |
Type |
Journal Article |
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Year |
2010 |
Publication |
Plant Systematics and Evolution |
Abbreviated Journal |
Plant Syst. Evol. |
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Volume |
287 |
Issue |
3-4 |
Pages |
179-187 |
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Keywords |
Floral volatiles; Ocimene; Insect pollination; Reproductive success; Sphaeroceridae; Thermogenesis |
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Abstract |
Pollination in the genus Arum appears to be in general a complex deceptive pollination process. The genus Arum is composed of 28 species, all belonging to the subgenus Arum, except A. pictum, the only species of the subgenus Gymnomesium, which is basal and sister to all other Arum species. The aim of this paper is to document the pollination ecology of the insular Arum pictum, the only Arum species to flower in autumn, on the island of Corsica (France). The anthesis cycle of A. pictum occurs during the day, attracting sphaerocerid flies and staphylinid beetles early in the morning and late in the afternoon of the first day. The pollen is released from the anthers early in the morning of the second day before the departure of the insects. Its thermogenic cycle matches the anthesis cycle with an original and unique, bimodal temperature pattern of the appendix (morning and afternoon), contrary to the unimodal pattern found in all other studied Arum species. Data from reproductive success and seed sets suggest that sexual reproduction in this species is limited by pollen (e.g. attracting lured insects) rather than by resources. The biology of this Western Mediterranean species appears to be different from other Western European Arum and close to some Eastern Mediterranean species. Further studies are needed to establish whether Arum pictum represents some ancestral stage or whether its peculiar biological traits are adapted to its insular distribution. |
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Address |
[Quilichini, Angelique; Gibernau, Marc] CNRS, UMR 8172, Ecole Forets Guyane, F-97387 Kourou, France, Email: marc.gibernau@ecofog.gf |
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SPRINGER WIEN |
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0378-2697 |
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Notes |
ISI:000279479800008 |
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no |
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EcoFoG @ eric.marcon @ |
Serial |
51 |
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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. |
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Title |
Variations in chemical and physical properties of Amazon forest soils in relation to their genesis |
Type |
Journal Article |
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Year |
2010 |
Publication |
Biogeosciences |
Abbreviated Journal |
Biogeosciences |
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Volume |
7 |
Issue |
5 |
Pages |
1515-1541 |
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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. |
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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 |
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COPERNICUS GESELLSCHAFT MBH |
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ISSN |
1726-4170 |
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Notes |
ISI:000278184500011 |
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no |
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Call Number |
EcoFoG @ eric.marcon @ |
Serial |
58 |
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Author |
Prevost-Boure, N.C.; Ngao, J.; Berveiller, D.; Bonal, D.; Damesin, C.; Dufrene, E.; Lata, J.C.; Le Dantec, V.; Longdoz, B.; Ponton, S.; Soudani, K.; Epron, D. |
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Title |
Root exclusion through trenching does not affect the isotopic composition of soil CO2 efflux |
Type |
Journal Article |
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Year |
2009 |
Publication |
Plant and Soil |
Abbreviated Journal |
Plant Soil |
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Volume |
319 |
Issue |
1-2 |
Pages |
1-13 |
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Keywords |
Stable carbon isotopes; Natural abundance; Soil respiration; Trenched plot; Rainforest; Temperate forest |
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Abstract |
Disentangling the autotrophic and heterotrophic components of soil CO2 efflux is critical to understanding the role of soil system in terrestrial carbon (C) cycling. In this study, we combined a stable C-isotope natural abundance approach with the trenched plot method to determine if root exclusion significantly affected the isotopic composition (delta C-13) of soil CO2 efflux (R-S). This study was performed in different forest ecosystems: a tropical rainforest and two temperate broadleaved forests, where trenched plots had previously been installed. At each site, R-S and its delta C-13 (delta C-13(Rs)) tended to be lower in trenched plots than in control plots. Contrary to R-S, delta C-13(Rs) differences were not significant. This observation is consistent with the small differences in delta C-13 measured on organic matter from root, litter and soil. The lack of an effect on delta C-13(Rs) by root exclusion could be from the small difference in delta C-13 between autotrophic and heterotrophic soil respirations, but further investigations are needed because of potential artefacts associated with the root exclusion technique. |
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Address |
[Prevost-Boure, Nicolas Chemidlin; Berveiller, Daniel; Damesin, Claire; Dufrene, Eric; Lata, Jean-Christophe; Soudani, Kamel] Univ Paris Sud, Lab Ecol Systemat & Evolut, AgroParisTech, CNRS,UMR 8079, F-75231 Paris, France, Email: nicolas.chemidlin-prevost-boure@u-psud.fr |
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SPRINGER |
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ISSN |
0032-079X |
ISBN |
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Notes |
ISI:000266143400001 |
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no |
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Call Number |
EcoFoG @ eric.marcon @ |
Serial |
203 |
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Author |
Brechet, L.; Ponton, S.; Roy, J.; Freycon, V.; Couteaux, M.M.; Bonal, D.; Epron, D. |
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Title |
Do tree species characteristics influence soil respiration in tropical forests? A test based on 16 tree species planted in monospecific plots |
Type |
Journal Article |
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Year |
2009 |
Publication |
Plant and Soil |
Abbreviated Journal |
Plant Soil |
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Volume |
319 |
Issue |
1-2 |
Pages |
235-246 |
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Keywords |
Fine root; Litter quality; Nutrient cycling; Plant soil interactions; Soil respiration; Tropical plantations |
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Abstract |
The high spatial variability of soil respiration in tropical rainforests is well evaluated, but influences of biotic factors are not clearly understood. This study underlines the influence of tree species characteristics on soil respiration across a 16-monospecific plot design in a tropical plantation of French Guiana. A large variability of soil CO2 fluxes was observed among plots (i.e. 2.8 to 6.8 μmol m(-2) s(-1)) with the ranking being constant across seasons. There were no significant relationships between soil respiration and soil moisture or soil temperature, neither spatially, nor seasonally. The variability of soil respiration was mainly explained by quantitative factors such as leaf litterfall and basal area. Surprisingly, no significant relationship was observed between soil respiration and root biomass. However, the influence of substrate quality was revealed by a strong relationship between soil respiration and litterfall P (and litterfall N, to a lesser extent). |
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Address |
[Ponton, Stephane] Natl Inst Agr Res INRA Ctr Rech Nancy, Forest Ecol & Ecophysiol Unit, UMR EEF, F-54280 Seichamps, France, Email: ponton@nancy.inra.fr |
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SPRINGER |
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0032-079X |
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Notes |
ISI:000266143400020 |
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no |
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Call Number |
EcoFoG @ eric.marcon @ |
Serial |
110 |
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Author |
Pickett, K.M.; Carpenter, J.M.; Dejean, A. |
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Title |
“Basal” but not primitive: the nest of Apoica arborea de Saussure, 1854 (Insecta, Hymenoptera, Vespidae, Polistinae) |
Type |
Journal Article |
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Year |
2009 |
Publication |
Zoosystema |
Abbreviated Journal |
Zoosystema |
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Volume |
31 |
Issue |
4 |
Pages |
945-948 |
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Keywords |
Insecta; Hymenoptera; Vespidae; Polistinae; Apoica; social wasps; nest architecture; mosaic evolution |
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Abstract |
The first nest of Apoica arborea ever collected is reported. Characteristics of the unusual nest design are discussed relative to other members of the genus Apoica and other epiponine genera. The characteristics of its nest architecture are a mosaic of primitive and derived features for the Polistinae, and thus the nest design is not properly interpreted as the primitive condition from which other swarm-founding wasp nest designs are derived. The frequent conflation of “basal” and primitive is discussed. |
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Address |
[Pickett, Kurt M.] Univ Vermont, Dept Biol, Burlington, VT 05401 USA, Email: kurt.pickett@uvm.edu |
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PUBLICATIONS SCIENTIFIQUES DU MUSEUM, PARIS |
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ISSN |
1280-9551 |
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Notes |
ISI:000273733000008 |
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no |
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Call Number |
EcoFoG @ eric.marcon @ |
Serial |
188 |
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Author |
Picard, N.; Mortier, F.; Rossi, V.; Gourlet-Fleury, S. |
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Title |
Clustering species using a model of population dynamics and aggregation theory |
Type |
Journal Article |
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Year |
2010 |
Publication |
Ecological Modelling |
Abbreviated Journal |
Ecol. Model. |
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Volume |
221 |
Issue |
2 |
Pages |
152-160 |
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Keywords |
Aggregation theory; Species grouping; Species richness; Tropical rainforest; Usher model |
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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. |
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[Picard, Nicolas; Mortier, Frederic; Rossi, Vivien; Gourlet-Fleury, Sylvie] CIRAD, F-34398 Montpellier 5, France, Email: nicolas.picard@cirad.fr |
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ELSEVIER SCIENCE BV |
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0304-3800 |
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ISI:000273628800004 |
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EcoFoG @ eric.marcon @ |
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85 |
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