|   | 
Details
   web
Records
Author Ntienoue, J.K.; Reguer, A.; Robert, F.; Nait-Rabah, O.; Roos, C.
Title Electrochemical behaviour of a super austenitic stainless steel in amazonian aqueous environment Type Journal Article
Year 2013 Publication International Journal of Electrochemical Science Abbreviated Journal Int.J.Electrochem.Sci.
Volume 8 Issue 4 Pages 4761-4775
Keywords Cyclic voltammetry; Eis; Esem; Passive films; Stainless steel
Abstract The electrochemical behaviour of 254 SMO super austenitic stainless steel in natural seawater collected from river mouth of French Guiana was investigated. A comparative study of samples immersed during 22 days in this environment was made including influences of scraped biofilm introduced in experiments and of stirring. Electrochemical measurements – open circuit potential (OCP), electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV) and linear polarisation (LP) – are used to characterize the metal/medium interface included biofilms adhesion. The EDX analysis (EDAX system) shows that the chemical composition of adhered biofilm consists mostly of iron, oxygen, silicon and aluminium and seem preferentially bind on metal defects. © 2013 by ESG.
Address (up) Laboratoire Matériaux et Molécules en Milieu Amazonien, Université des Antilles et de la Guyane, UAG-UMR ECOFOG, Campus Trou Biran, Cayenne 97337, French Guiana
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 14523981 (Issn) ISBN Medium
Area Expedition Conference
Notes Export Date: 24 April 2013; Source: Scopus; Language of Original Document: English; Correspondence Address: Roos, C.; Laboratoire Matériaux et Molécules en Milieu Amazonien, Université des Antilles et de la Guyane, UAG-UMR ECOFOG, Campus Trou Biran, Cayenne 97337, French Guiana; email: christophe.roos@guyane.univ-ag.fr Approved no
Call Number EcoFoG @ webmaster @ Serial 483
Permanent link to this record
 

 
Author Suedile, F.; Robert, F.; Roos, C.; Lebrini, M.
Title Corrosion inhibition of zinc by Mansoa alliacea plant extract in sodium chloride media: Extraction, Characterization and Electrochemical Studies Type Journal Article
Year 2014 Publication Electrochimica Acta Abbreviated Journal Electrochim Acta
Volume 133 Issue Pages 631-638
Keywords Corrosion; Inhibition; Mansoa alliacea; sodium chloride; zinc
Abstract Ethanol extract of Mansoa alliacea was tested as corrosion inhibitor for zinc in NaCl 3% media using polarization and electrochemical impedance spectroscopy (EIS). Potentiodynamic polarization curves indicated that the plant extract behaves as mixed-type inhibitor. Impedance measurements showed that there are two phenomena in the process of inhibition. The results obtained show that this plant extract could serve as an effective inhibitor for the corrosion of zinc in NaCl 3% media. The extract obtained give inhibition around 90%. The experimental data obtained from EIS method show a frequency distribution and therefore a modelling element with frequency dispersion behaviour, a constant phase element (CPEα,Q) has been used. Graphical methods are illustrated by synthetic data to determine the parameter of CPE (α, Q). Polarization curves show that Mansoa alliacea extract affects the anodic and cathodic reactions and the corrosion potential values were shifted to the positive potentials in the presence of the crude extract. Studies on the phytochemical constituents of the total extract were also established. Electrochemical studies, on the chemical families present in the crude extract, were also carried out to find the main constituents responsible for corrosion inhibition properties of the plant extract. © 2014 Elsevier Ltd.
Address (up) Laboratoire Matériaux et Molécules en Milieux Amazonien, UAG – UMR ECOFOG Campus Troubiran, Route de Baduel, 97337 Cayenne, French Guiana
Corporate Author Thesis
Publisher Elsevier Ltd Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 00134686 (Issn) ISBN Medium
Area Expedition Conference
Notes Export Date: 18 June 2014; Coden: Elcaa; Correspondence Address: Lebrini, M.; Laboratoire Matériaux et Molécules en Milieux Amazonien, UAG – UMR ECOFOG Campus Troubiran, Route de Baduel, 97337 Cayenne, French Guiana; email: mounim.lebrini@guyane.univ-ag.fr Approved no
Call Number EcoFoG @ webmaster @ Serial 548
Permanent link to this record
 

 
Author Dejean, A.; Groc, S.; Herault, B.; Rodriguez-Pérez, H.; Touchard, A.; Céréghino, R.; Delabie, J.H.C.; Corbara, B.
Title Bat aggregation mediates the functional structure of ant assemblages Type Journal Article
Year 2015 Publication Comptes Rendus – Biologies Abbreviated Journal Comptes Rendus – Biologies
Volume 338 Issue 10 Pages 688-695
Keywords Ant functional groups; Bat roosts; Biogeochemical hotspots; Bioindicators; Stable isotopes
Abstract In the Guianese rainforest, we examined the impact of the presence of guano in and around a bat roosting site (a cave). We used ant communities as an indicator to evaluate this impact because they occupy a central place in the functioning of tropical rainforest ecosystems and they play different roles in the food web as they can be herbivores, generalists, scavengers or predators. The ant species richness around the cave did not differ from a control sample situated 500m away. Yet, the comparison of functional groups resulted in significantly greater numbers of detritivorous fungus-growing and predatory ant colonies around the cave compared to the control, the contrary being true for nectar and honeydew feeders. The role of bats, through their guano, was shown using stable isotope analyses as we noted significantly greater δ15N values for the ant species captured in and around the cave compared to controls. © 2015 Académie des sciences.
Address (up) Laboratoire Microorganismes, Génome et Environnement, Université Clermont-Auvergne, Université Blaise-Pascal, BP 10448, Clermont-Ferrand, 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 ISBN Medium
Area Expedition Conference
Notes Export Date: 2 October 2015 Approved no
Call Number EcoFoG @ webmaster @ Serial 625
Permanent link to this record
 

 
Author Odonne, G.; Herbette, G.; Eparvier, V.; Bourdy, G.; Rojas, R.; Sauvain, M.; Stien, D.
Title Antileishmanial sesquiterpene lactones from Pseudelephantopus spicatus, a traditional remedy from the Chayahuita Amerindians (Peru). Part III Type Journal Article
Year 2011 Publication Journal of Ethnopharmacology Abbreviated Journal J. Ethnopharmacol.
Volume 137 Issue 1 Pages 875-879
Keywords Asteraceae; Chayahuita; Hirsutinolides; Leishmaniasis; Peru; Pseudelephantopus spicatus; Traditional remedy; 8,13 diacetylpiptocarphol; acetyl 13 o ethylpiptocarphol; amphotericin B; antileishmanial agent; plant extract; Pseudelephantopus spicatus extract; sesquiterpene lactone derivative; unclassified drug; ursolic acid; amastigote; article; biological activity; Ic 50; in vitro study; Leishmania; leishmaniasis; medicinal plant; nonhuman; Peru; Pseudelephantopus spicatus; traditional medicine; Asteraceae; Leishmania amazonensis; Pseudelephantopus spicatus
Abstract Ethnopharmacological relevance: The study of traditional remedies used by the Chayahuita, an ethnic group from the Peruvian Amazonia, has prompted us to investigate in detail the ethanolic extract of Pseudelephantopus spicatus (Juss. ex Aubl.) C.F. Baker, which has demonstrated strong biological activity towards Leishmania amazonensis. Our goal was to discover the active compound of this plant-based remedy. Materials and methods: A bioguided fractionation of the crude extract was undertaken based on the biological activity recorded against Leishmania amazonensis axenic amastigotes in in vitro bioassays. Results: Three strongly to moderately active compounds were isolated: two hirsutinolides (the 8,13-diacetyl-piptocarphol and the 8-acetyl-13-O-ethyl-piptocarphol) and ursolic acid. IC50 against Leishmania amazonensis axenic amastigotes are respectively 0.2, 0.37 and 0.99 μM (while IC50 of amphotericin B is 0.41 μM). These compounds have never been isolated from this plant species, and germacranolides have never been identified as potential antileishmanial agents. Conclusions: The compounds isolated from Pseudelephantopus spicatus account for the antileishmanial activity of the plant, thus giving support to its use by the Chayahuita in Peru. © 2011 Elsevier Ireland Ltd All rights reserved.
Address (up) Laboratorio de Investigación y Desarrollo, Facultad de Ciencias y Filosofía, Universidad Peruana Cayetano Heredia, Avenida Honorio Delgado 430, San Martin de Porres, Lima, Peru
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 03788741 (Issn) ISBN Medium
Area Expedition Conference
Notes Export Date: 21 October 2011; Source: Scopus; Coden: Joetd; doi: 10.1016/j.jep.2011.07.008; Language of Original Document: English; Correspondence Address: Odonne, G.; Bureau du CNRS en Guyane, CNRS – UPS 2561, 2 Avenue Gustave Charlery, 97300 Cayenne, France; email: guillaume.odonne@gmail.com; Chemicals/CAS: amphotericin B, 1397-89-3, 30652-87-0; ursolic acid, 77-52-1 Approved no
Call Number EcoFoG @ webmaster @ Serial 350
Permanent link to this record
 

 
Author Bréchet, L.; Courtois, E.A.; Saint-Germain, T.; Janssens, I.A.; Asensio, D.; Ramirez-Rojas, I.; Soong, J.L.; Van Langenhove, L.; Verbruggen, E.; Stahl, C.
Title Disentangling Drought and Nutrient Effects on Soil Carbon Dioxide and Methane Fluxes in a Tropical Forest Type Journal Article
Year 2019 Publication Frontiers in Environmental Science Abbreviated Journal Front. Environ. Sci.
Volume 7 Issue 180 Pages
Keywords carbon dioxide; drought; fertilization; methane; nitrogen; phosphorus; soil GHG fluxes; tropical forest
Abstract Tropical soils are a major contributor to the balance of greenhouse gas (GHG) fluxes in the atmosphere. Models of tropical GHG fluxes predict that both the frequency of drought events and changes in atmospheric deposition of nitrogen (N) will significantly affect dynamics of soil carbon dioxide (CO2) and methane (CH4) production and consumption. In this study, we examined the combined effect of a reduction in precipitation and an increase in nutrient availability on soil CO2 and CH4 fluxes in a primary French Guiana tropical forest. Drought conditions were simulated by intercepting precipitation falling through the forest canopy with tarpaulin roofs. Nutrient availability was manipulated through application of granular N and/or phosphorus (P) fertilizer to the soil. Soil water content (SWC) below the roofs decreased rapidly and stayed at continuously low values until roof removal, which as a consequence roughly doubled the duration of the dry season. After roof removal, SWC slowly increased but remained lower than in the control soils even after 2.5 months of wet-season precipitation. We showed that drought-imposed reduction in SWC decreased the CO2 emissions (i.e., CO2 efflux), but strongly increased the CH4 emissions. N, P, and N × P (i.e., NP) additions all significantly increased CO2 emission but had no effect on CH4 fluxes. In treatments where both fertilization and drought were applied, the positive effect of N, P, and NP fertilization on CO2 efflux was reduced. After roof removal, soil CO2 efflux was more resilient in the control plots than in the fertilized plots while there was only a modest effect of roof removal on soil CH4 fluxes. Our results suggest that a combined increase in drought and nutrient availability in soil can locally increase the emissions of both CO2 and CH4 from tropical soils, for a long term.
Address (up) Lawrence Berkeley National Laboratory, Climate and Ecosystem Science Division, Berkeley, CA, United States
Corporate Author Thesis
Publisher Frontiers Media S.A. Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2296665x (Issn) ISBN Medium
Area Expedition Conference
Notes Export Date: 16 December 2019; Correspondence Address: Bréchet, L.; Centre of Excellence PLECO (Plant and Ecosystems), Department of Biology, University of AntwerpBelgium; email: laeti.brechet@gmail.com Approved no
Call Number EcoFoG @ webmaster @ Serial 899
Permanent link to this record
 

 
Author Marcon, E.; Puech, F.; Traissac, S.
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 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 (up) 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
Permanent link to this record
 

 
Author Clair, B.; Déjardin, A.; Pilate, G.; Alméras, T.
Title Is the G-layer a tertiary cell wall? Type Journal Article
Year 2018 Publication Frontiers in Plant Science Abbreviated Journal
Volume 9 Issue Pages 623
Keywords Flax; G-layer; Gelatinous layer; Maturation stress; Secondary cell wall; Tension wood; Tertiary cell wall
Abstract
Address (up) LMGC, CNRS, Université de Montpellier, Montpellier, 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 ISBN Medium
Area Expedition Conference
Notes Export Date: 31 May 2018 Approved no
Call Number EcoFoG @ webmaster @ Serial 805
Permanent link to this record
 

 
Author Dulormne, M.; Musseau, O.; Muller, F.; Toribio, A.; Bâ, A.
Title Effects of NaCl on growth, water status, N2 fixation, and ion distribution in Pterocarpus officinalis seedlings Type Journal Article
Year 2010 Publication Plant and Soil Abbreviated Journal Plant and Soil
Volume 327 Issue 1 Pages 23-34
Keywords Bradyrhizobium; Leaf water potential; Nodulation; Salt; Swamp forest
Abstract Pterocarpus officinalis (Fabaceae) dominates in the swamp forests of the Lesser Antilles, submitted to strong variations of soil salinity (30-445 mM). This study aimed to assess the effect of salinity on growth, nodulation, N2 fixation, water status and ions content in P. officinalis and to clarify the mechanisms involved. Seedlings inoculated or not with two strains from areas of contrasting salinity levels (< to 50 or 445 mM) were watered with 0, 171 and 342 mM solutions of NaCl in greenhouse conditions. Non-inoculated seedlings were tolerant to a salinity of 171 mM, with no significant effect on seedling biomass. Evapotranspiration per unit of leaf area (E/TLa) remained unchanged at 171 mM. Maintenance of a constant E/TLa and especially the control of ion transport to the upper parts of the plant could explain seedling salt tolerance up to intermediate salinity conditions (171 mM). The two strains have a 99.8% genetic identity in spite of differences in their original habitats, this explaining the similar response of the symbiosis to salinity. The higher salt sensitivity of inoculated seedlings was linked to the sensitivity of both Bradyrhizobium strains (reduction of free-living cells) and to that of the nodulation process (fewer nodules and inhibition of N2-fixation) to intermediate salinity. © Springer Science + Business Media B.V. 2009.
Address (up) LSTM-UMR 113, Université des Antilles et de la Guyane, UFR des Sciences Exactes et Naturelles, B.P. 592, 97159 Pointe-à-Pitre, Guadeloupe (F.W.I.), 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 ISBN Medium
Area Expedition Conference
Notes Cited By :12; Export Date: 7 February 2017 Approved no
Call Number EcoFoG @ webmaster @ Serial 727
Permanent link to this record
 

 
Author Dézerald, O.; Srivastava, D.S.; Céréghino, R.; Carrias, J.-F.; Corbara, B.; Farjalla, V.F.; Leroy, C.; Marino, N.A.C.; Piccoli, G.C.O.; Richardson, B.A.; Richardson, M.J.; Romero, G.Q.; González, A.L.
Title Functional traits and environmental conditions predict community isotopic niches and energy pathways across spatial scales Type Journal Article
Year 2018 Publication Functional Ecology Abbreviated Journal
Volume 32 Issue 10 Pages 2423-2434
Keywords energy pathways; environmental heterogeneity; food webs; functional biogeography; functional diversity; isotopic niche; metacommunity; trophic structure
Abstract Despite ongoing research in food web ecology and functional biogeography, the links between food web structure, functional traits and environmental conditions across spatial scales remain poorly understood. Trophic niches, defined as the amount of energy and elemental space occupied by species and food webs, may help bridge this divide. Here, we ask how the functional traits of species, the environmental conditions of habitats and the spatial scale of analysis jointly determine the characteristics of trophic niches. We used isotopic niches as a proxy of trophic niches, and conducted analyses at spatial scales ranging from local food webs and metacommunities to geographically distant sites. We sampled aquatic macroinvertebrates from 104 tank bromeliads distributed across five sites from Central to South America and compiled the macroinvertebrates’ functional traits and stable isotope values (δ15N and δ13C). We assessed how isotopic niches within each bromeliad were influenced by the functional trait composition of their associated invertebrates and environmental conditions (i.e., habitat size, canopy cover [CC] and detrital concentration [DC]). We then evaluated whether the diet of dominant predators and, consequently, energy pathways within food webs reflected functional and environmental changes among bromeliads across sites. At last, we determined the extent to which the isotopic niches of macroinvertebrates within each bromeliad contributed to the metacommunity isotopic niches within each site and compared these metacommunity-level niches over biogeographic scales. At the bromeliad level, isotopic niches increased with the functional richness of species in the food web and the DC in the bromeliad. The diet of top predators tracked shifts in prey biomass along gradients of CC and DC. Bromeliads that grew under heterogeneous CC displayed less trophic redundancy and therefore combined to form larger metacommunity isotopic niches. At last, the size of metacommunity niches depended on within-site heterogeneity in CC. Our results suggest that the trophic niches occupied by food webs can predictably scale from local food webs to metacommunities to biogeographic regions. This scaling process is determined by both the functional traits of species and heterogeneity in environmental conditions. A plain language summary is available for this article. © 2018 The Authors. Functional Ecology © 2018 British Ecological Society
Address (up) Luquillo LTER, Institute for Tropical Ecosystem Studies, College of Natural Sciences, University of Puerto Rico at Rio Piedras, San Juan, Puerto Rico
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 ISBN Medium
Area Expedition Conference
Notes Export Date: 22 October 2018 Approved no
Call Number EcoFoG @ webmaster @ Serial 828
Permanent link to this record
 

 
Author Dejean, A.; Corbara, B.; Roux, O.; Orivel, J.
Title The antipredatory behaviours of neotropical ants towards army ant raids (Hymenoptera: Formicidae) Type Journal Article
Year 2014 Publication Myrmecological News Abbreviated Journal Myrmecological News
Volume 19 Issue Pages 17-24
Keywords Antipredatory behaviour; Army ants; Ecitoninae; Prey-ant species
Abstract Group hunting, nomadism, wingless queens and colony fission characterize army ants, allowing them to have become the main tropical arthropod predators, mostly of other social insects. We studied the reactions of different ant species to the New World army ants Eciton burchellii (WESTWOOD, 1842) and E. hamatum (FABRICIUS, 1782) (Ecitoninae). We compiled our results with those already known in a synthetic appendix. A wide range of ant species react to the ap-proach of army ant raids by evacuating their nests with several workers transporting brood. The Eciton plunder a large part of the brood but rarely kill workers or queens, so that the latter return to their nest and resume colony activity. One exception is Paratrechina longicornis (LATREILLE, 1802) colonies that quickly evacuate their nest, so that the entire col-ony can generally escape a raid. Another is Leptogenys mexicana (MAYR, 1870) that leave their nests in columns while some nestmates resist the attack; they therefore lose only a few larvae. We noted that colonies can avoid being raided if the army ants ignore them (Atta cephalotes (LINNAEUS, 1758)), or if the workers produce a repellent substance (Azteca associated with myrmecophytic Cecropia) or are repellent themselves (Pachycondyla villosa (FABRICIUS, 1804), Ec-tatomma spp.). In the other cases, a part of the brood is lost. When an Eciton raid approached the base of their host-tree trunk, Azteca andreae GUERRERO, DELABIE and DEJEAN, 2010 workers dropped a part of their brood on the ground. While numerous Eciton workers were gathering up this brood, the front of the column advanced, so that the Azteca andreae nests were not plundered. Pheidole megacephala (FABRICIUS, 1793) nests were partly plundered as the workers reacted aggressively, blocking the Eciton inside their nests during a long time. When the latter returned toward their bivouac, they were attacked and killed by their nestmates whether or not they had retrieved Pheidole brood. Consequently, the front of the column turned away from the Pheidole nest.
Address (up) Maladies Infectieuses et Vecteurs, Evolution et Contrôle (UMR- IRD 224) Équipe BEES, IRD 01, BP 171 Bobo-Dioulasso, Burkina Faso
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 19944136 (Issn) ISBN Medium
Area Expedition Conference
Notes Export Date: 10 March 2014; Source: Scopus; Language of Original Document: English; Correspondence Address: Dejean, A.; Écologie des Forêts de Guyane (UMR-CNRS 8172), Campus agronomique, BP 316, 97379 Kourou cedex, France; email: alain.dejean@wanadoo.fr Approved no
Call Number EcoFoG @ webmaster @ Serial 535
Permanent link to this record