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Author Ntienoue, J.K.; Reguer, A.; Robert, F.; Nait-Rabah, O.; Roos, C. pdf  url
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  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 (down) 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 Laboratoire Matériaux et Molécules en Milieu Amazonien, Université des Antilles et de la Guyane, UAG-UMR ECOFOG, Campus Trou Biran, Cayenne 97337, French Guiana  
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  ISSN 14523981 (Issn) ISBN Medium  
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  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  
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Author Bordenave, B.; Lehir, F.; Lorans, M. url  openurl
  Title Current knowledge on threatened plant species of French Guiana Type Journal Article
  Year 2012 Publication Revue d'Ecologie (La Terre et la Vie) Abbreviated Journal Rev. Ecol. Terre Vie  
  Volume 67 Issue Suppl.2 Pages 29-45  
  Keywords  
  Abstract (down) The elaboration of a first list of the most threatened species of the overseas territory of French Guyana was undertaken in 2009 by the Association for Botanical Conservation in French Guiana in collaboration with the National Botanical Conservatory of Brest. Carried out in synergy with the updating of the species list for Natural Areas of Ecological, Faunistic and Floritic Interests supervised by the Region Science Council for Natural Heritage, this work includes 97 vascular plants, 18 of which can be considered as threatened in the state of current knowledge, according to the IUCN criteria which are recommended by the Federation of National Botanical Conservatories. Among these 18 taxa, threatened because of their rarity and the fragility of their natural habitats, 17 are already protected by a 2001 ministry decree and one is from a new genus, Hekkingia bordenavei; nine of these appear to be of high concern for conservation: Cleistes grandifiora (Orchidaceae), Cornutia pubescens (Verbenaceae), Antirhea triflora (Rubiaceae), Himathantus drasticus (Apocynaceae), Axonopus oiapocensis (Poaceae), Psychotria granvillei (Rubiaceae), Eriocaulon guyanense (Eriocaulaceae) along with two palm species subject to National Action Plans for their conservation since 2009, Astrocaryum minus and Bactris nancibaensis. This study also contributes to the on-going “regional Red List” of the French Guiana flora.  
  Address Étudiant en Master 2, Écologie des Forêts Tropicales, Université de Kourou, 1 rue de l'Université, 97310 Kourou, Guyane Française, France  
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  ISSN 02497395 (Issn) ISBN Medium  
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  Notes Export Date: 13 April 2012; Source: Scopus; Coden: Retve; Language of Original Document: French; Correspondence Address: Bordenave, B.; BGB Consultance, Botanique Tropicale, 9 route des grandes roches, 29910 Trégunc, France; email: bruno.bordenave@wanadoo.fr Approved no  
  Call Number EcoFoG @ webmaster @ Serial 390  
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Author Sist, P.; Nguyen-The, N. openurl 
  Title Logging damage and the subsequent dynamics of a dipterocarp forest in East Kalimantan (1990-1996) Type Journal Article
  Year 2002 Publication Forest Ecology and Management Abbreviated Journal For. Ecol. Manage.  
  Volume 165 Issue 1-3 Pages 85-103  
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  Abstract (down) The effects of logging damage on forest dynamics processes were assessed in a lowland dipterocarp forest of East Kalimantan, Indonesia. From 1990 to 1991, twelve 4 ha plots (200 m x 200 m) each divided into four I ha subplots were set up and all trees with dbh greater than or equal to 10 cm measured and identified at least at the generic level. Logging was carried out from November 1991 to March 1992 in nine plots while three plots served as control. The 48 subplots were grouped according to the proportion Of remaining basal area after harvesting, as follows: group I with more than 80% of the original basal area remaining, group 2 with 70-79%, group 3 with less than 70%, and group 4 as control plots. Remeasurements were carried out just after logging in 1992 and then every 2 years until 1996. Felling intensity varied from I to 17 stems ha(-1) (50-250 m(3) ha(-1)). In primary forest, mean annual mortality remained constant to 1.5% per year throughout the study period while mean annual mortality rate was significantly higher in logged-over forest (2.6% per year). This higher rate resulted from a higher mortality of injured trees (4.9% per year). Four years after logging, mortality rates in logged-over and primary forest were similar. Recruitment remained constant at 8 trees ha(-1) per year in primary forest and varied from 14 to 32 trees ha(-1) per year in logged-over stand in proportion with the amount of damage. In stands with the lowest remaining basal area, the establishment and growth of dipterocarps was strongly limited by the strong regeneration of pioneer species. This study suggests that total basal area removed by logging in primary forest (harvested trees and trees killed during felling and skidding) should not exceed 15% of the original one; reduced-impact logging (RIL) techniques applied with a maximum harvesting intensity of 8 trees ha(-1), can keep logging damage under this threshold. (C) 2002 Elsevier Science B.V. All rights reserved.  
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  ISSN 0378-1127 ISBN Medium  
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  Notes WOS:000176620100008 Approved no  
  Call Number EcoFoG @ webmaster @ Serial 312  
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Author Li, M.C.; Royer, M.; Stien, D.; Lecante, A.; Roos, C. openurl 
  Title Inhibitive effect of sodium eperuate on zinc corrosion in alkaline solutions Type Journal Article
  Year 2008 Publication Corrosion Science Abbreviated Journal Corrosion Sci.  
  Volume 50 Issue 7 Pages 1975-1981  
  Keywords zinc; concrete; EIS; alkaline corrosion; passivity  
  Abstract (down) The effect of sodium eperuate prepared from Wallaba (Eperua falcata Aubl) extract on zinc corrosion was investigated in alkaline solutions with chloride ions (i.e., simulated concrete pore solutions) by using electrochemical techniques. Sodium eperuate inhibits the corrosion of zinc in 0.1 M NaCl solutions with pH 9.6. As its concentration increases to 1 g/L, the inhibition efficiency reaches approximately 92%. In alkaline solutions with pH 12.6, sodium eperuate has no adverse effect on passivity of zinc, and retards the chloride attack. These suggest that sodium eperuate is an effective inhibitor for the protection of zinc in alkaline environments. (c) 2008 Elsevier Ltd. All rights reserved.  
  Address [Li, M. C.; Royer, M.; Stien, D.] UMR ECOFOG, CNRS, F-97337 Cayenne, French Guiana, Email: mouchengli@yahoo.com.cn  
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  Publisher PERGAMON-ELSEVIER SCIENCE LTD Place of Publication Editor  
  Language Summary Language Original Title  
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  Series Volume Series Issue Edition  
  ISSN 0010-938X ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000258543600021 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 132  
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Author Lebrini, M.; Robert, F.; Blandinieres, P.A.; Roos, C. pdf  openurl
  Title Corrosion Inhibition by Isertia coccinea Plant Extract in Hydrochloric Acid Solution Type Journal Article
  Year 2011 Publication International Journal of Electrochemical Science Abbreviated Journal Int. J. Electrochem. Sci.  
  Volume 6 Issue 7 Pages 2443-2460  
  Keywords Isertia coccinea; corrosion inhibitors; C38 steel; acidic media; adsorption  
  Abstract (down) The effect of alkaloids extracted from Isertia coccinea plant (AEIC) on the corrosion of C38 steel in 1 M hydrochloric acid was investigated by electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization techniques. Potentiodynamic polarization curves indicated that the extract behave as mixed-type inhibitor. The experimental data obtained from EIS method show a frequency distribution and therefore a modelling element with frequency dispersion behaviour, a constant phase element (CPE) has been used. The inhibition efficiencies of the extract calculated by three methods show the same tendency. Inhibition was found to increase with increasing concentration of the plant extract. The results obtained show that the extract solution of the plant could serve as an effective inhibitor for the corrosion of C38 steel in hydrochloric acid solution. The apparent activation energy of the process taking place in inhibitor presence was determined on the ground of four temperature values in the range from 25 degrees C to 55 degrees C using the data obtained by two independent methods. Theoretical fitting of different isotherms, Langmuir, Temkin and Frunkin, were tested to clarify the nature of adsorption.  
  Address [Lebrini, M.; Robert, F.; Blandinieres, P. A.; Roos, C.] UAG UMR ECOFOG, Lab Mat & Mol Milieu Amazonien, Cayenne 97337, French Guiana, Email: florent.robert@guyane.univ-ag.fr  
  Corporate Author Thesis  
  Publisher Electrochemical Science Group Place of Publication Editor  
  Language Summary Language Original Title  
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  Series Volume Series Issue Edition  
  ISSN 1452-3981 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000292331400014 Approved no  
  Call Number EcoFoG @ webmaster @ Serial 324  
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Author Lecante, A.; Robert, F.; Blandinieres, P.A.; Roos, C. openurl 
  Title Anti-corrosive properties of S. tinctoria and G. ouregou alkaloid extracts on low carbon steel Type Journal Article
  Year 2011 Publication Current Applied Physics Abbreviated Journal Curr. Appl. Phys.  
  Volume 11 Issue 3 Pages 714-724  
  Keywords Low carbon steel; Acidic media; Corrosion inhibitor; Plant extract; EIS  
  Abstract (down) The effect of alkaloid extracts from two Amazonian trees (Guatteria ouregou and Simira tinctoria) on low carbon steel corrosion was investigated in acidic solutions by using electrochemical techniques. All of these plant extracts inhibit the corrosion of low carbon steel in 0.1 M HCl solutions. As their concentration increases to 250 mg/L, the inhibition efficiencies of S. tinctoria and G. ouregou alkaloid extracts reach approximately 92% in 0.1 M HCl solutions. The adsorption of the inhibitor molecules was in accordance with the Langmuir adsorption isotherm. The results obtained show that these plant extracts could be serve as an effective inhibitor for the corrosion of low carbon steel in hydrochloric acid media. Furthermore, harmane was identified as the main component of S. tinctoria extract and that suggests that it is the active ingredient against corrosion of low carbon steel. (C) 2010 Elsevier B.V. All rights reserved.  
  Address [Lecante, A.; Robert, F.; Blandinieres, P. A.; Roos, C.] UAG UMR ECOFOG, Lab Mat & Mol Milieu Amazonien, F-97337 Cayenne, French Guiana, France, Email: florent.robert@guyane.univ-ag.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 1567-1739 ISBN Medium  
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  Notes ISI:000288183300088 Approved no  
  Call Number EcoFoG @ webmaster @ Serial 300  
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Author Longo, M.; Knox, R.G.; Levine, N.M.; Swann, A.L.S.; Medvigy, D.M.; Dietze, M.C.; Kim, Y.; Zhang, K.; Bonal, D.; Burban, B.; Camargo, P.B.; Hayek, M.N.; Saleska, S.R.; Da Silva, R.; Bras, R.L.; Wofsy, S.C.; Moorcroft, P.R. pdf  url
doi  openurl
  Title The biophysics, ecology, and biogeochemistry of functionally diverse, vertically and horizontally heterogeneous ecosystems: The Ecosystem Demography model, version 2.2-Part 2: Model evaluation for tropical South America Type Journal Article
  Year 2019 Publication Geoscientific Model Development Abbreviated Journal Geoscientific Model Dev.  
  Volume 12 Issue 10 Pages 4347-4374  
  Keywords  
  Abstract (down) The Ecosystem Demography model version 2.2 (ED-2.2) is a terrestrial biosphere model that simulates the biophysical, ecological, and biogeochemical dynamics of vertically and horizontally heterogeneous terrestrial ecosystems. In a companion paper (Longo et al., 2019a), we described how the model solves the energy, water, and carbon cycles, and verified the high degree of conservation of these properties in long-term simulations that include long-term (multi-decadal) vegetation dynamics. Here, we present a detailed assessment of the model's ability to represent multiple processes associated with the biophysical and biogeochemical cycles in Amazon forests. We use multiple measurements from eddy covariance towers, forest inventory plots, and regional remote-sensing products to assess the model's ability to represent biophysical, physiological, and ecological processes at multiple timescales, ranging from subdaily to century long. The ED-2.2 model accurately describes the vertical distribution of light, water fluxes, and the storage of water, energy, and carbon in the canopy air space, the regional distribution of biomass in tropical South America, and the variability of biomass as a function of environmental drivers. In addition, ED-2.2 qualitatively captures several emergent properties of the ecosystem found in observations, specifically observed relationships between aboveground biomass, mortality rates, and wood density; however, the slopes of these relationships were not accurately captured. We also identified several limitations, including the model's tendency to overestimate the magnitude and seasonality of heterotrophic respiration and to overestimate growth rates in a nutrient-poor tropical site. The evaluation presented here highlights the potential of incorporating structural and functional heterogeneity within biomes in Earth system models (ESMs) and to realistically represent their impacts on energy, water, and carbon cycles. We also identify several priorities for further model development.  
  Address Georgia Institute of Technology, Atlanta, GA, United States  
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  Publisher Copernicus GmbH Place of Publication Editor  
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  ISSN 1991959x (Issn) ISBN Medium  
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  Notes Cited By :1; Export Date: 27 October 2019; Correspondence Address: Longo, M.; Harvard UniversityUnited States; email: mdplongo@gmail.com Approved no  
  Call Number EcoFoG @ webmaster @ Serial 890  
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Author Mathieu, A.; Letort, V.; Cournède, P.H.; Zhang, B.G.; Heuret, P.; De Reffye, P. url  openurl
  Title Oscillations in functional structural plant growth models Type Journal Article
  Year 2012 Publication Mathematical Modelling of Natural Phenomena Abbreviated Journal  
  Volume 7 Issue 6 Pages 47-66  
  Keywords Cecropia trees; Cucumber plant; Dynamic system of plant growth; Functional-structural plant models; GreenLab  
  Abstract (down) The dynamic model of plant growth GreenLab describes plant architecture and functional growth at the level of individual organs. Structural development is controlled by formal grammars and empirical equations compute the amount of biomass produced by the plant, and its partitioning among the growing organs, such as leaves, stems and fruits. The number of organs initiated at each time step depends on the trophic state of the plant, which is evaluated by the ratio of biomass available in plant to the demand of all the organs. The control of the plant organogenesis by this variable induces oscillations in the simulated plant behaviour. The mathematical framework of the GreenLab model allows to compute the conditions for the generation of oscillations and the value of the period according to the set of parameters. Two case-studies are presented, corresponding to emergence of oscillations associated to fructification and branching. Similar alternating patterns are commonly reported by botanists. In this article, two examples were selected: alternate patterns of fruits in cucumber plants and alternate appearances of branches in Cecropia trees. The model was calibrated from experimental data collected on these plants. It shows that a simple feedback hypothesis of trophic control on plant structure allows the emergence of cyclic patterns corresponding to the observed ones. © EDP Sciences, 2012.  
  Address CIRAD, UMR AMAP, Montpellier, France  
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  Notes Export Date: 27 December 2012; Source: Scopus Approved no  
  Call Number EcoFoG @ webmaster @ Serial 452  
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Author Dezerald, O.; Céréghino, R.; Corbara, B.; Dejean, A.; Leroy, C. url  openurl
  Title Functional trait responses of aquatic macroinvertebrates to simulated drought in a Neotropical bromeliad ecosystem Type Journal Article
  Year 2015 Publication Freshwater Biology Abbreviated Journal Freshwater Biology  
  Volume 60 Issue 9 Pages 1917-1929  
  Keywords Food webs; Precipitations; Rainforests; Resistance/resilience; Tipping point  
  Abstract (down) The duration of the dry seasons in south-eastern Amazonia is expected to increase. Little is known of how freshwater assemblages respond to drought in the humid rainforests and of the extent to which they resist the absence of rainfall before the collapse of the system. We manipulated rainshelters over tank-forming bromeliads (i.e. the interlocking leaf axils of these plants form wells that collect rainwater) to simulate an exceptionally long dry period (49 days, compared with a 10-year mean ± SD annual maximum number of 17 ± 5.3 days without rainfall at the study site) and then a rewetting period. By sampling weekly over 3 months, we followed the dynamics of the representation of abundance-weighted traits in invertebrate assemblages in these treatment plants and in a control group. The functional structure of assemblages was drought resistant until the water volume in the bromeliad pools dropped by 90%, when there was a sudden shift in the functional trait structure due to the loss of most populations except the drought-resistant culicids. Traits related to life history, body size and preferred food showed significant responses to drought. There was a convergence in the functional traits of species surviving in dry plants, strengthening the idea that environmental filtering, rather than stochasticity, determines the functional trajectory of aquatic assemblages during drought. At the end of the dry period, samples of the detritus potentially containing drought-resistant eggs/cysts (and eventually live larvae) were taken from the dry plants and rewetted in the laboratory, allowing us to distinguish resistant species from those requiring recolonisation via subsequent oviposition by adults from elsewhere. Patches of water-filled bromeliads persisting in the area provided the most important pool of colonists, and communities returned to the pre-disturbance state within 1-2 weeks of rewetting. Our results suggest that the functional trait structure of invertebrate assemblages in bromeliads could remain stable under scenarios of precipitation change that would triple the duration of current dry periods at a local scale. Future experiments should evaluate how environmental factors might alter the tipping point between resistance to drought and a collapse in ecosystem processes. © 2015 John Wiley & Sons Ltd.  
  Address IRD, UMR AMAP (botAnique et Modélisation de l'Architecture des Plantes et des vegetations), Boulevard de la Lironde, TA A-51/PS2, Montpellier Cedex 5, France  
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  Notes Export Date: 27 August 2015 Approved no  
  Call Number EcoFoG @ webmaster @ Serial 616  
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Author Houadria, M.; Blüthgen, N.; Salas-Lopez, A.; Schmitt, M.-I.; Arndt, J.; Schneider, E.; Orivel, J.; Menzel, F. url  openurl
  Title The relation between circadian asynchrony, functional redundancy, and trophic performance in tropical ant communities Type Journal Article
  Year 2016 Publication Ecology Abbreviated Journal Ecology  
  Volume 97 Issue 1 Pages 225-235  
  Keywords Diel turnover; Ecosystem functioning; Functional diversity; Multifunctional redundancy; Sampling effect; Temporal partitioning; Tropical rain forests  
  Abstract (down) The diversity-stability relationship has been under intense scrutiny for the past decades, and temporal asynchrony is recognized as an important aspect of ecosystem stability. In contrast to relatively well- studied interannual and seasonal asynchrony, few studies investigate the role of circadian cycles for ecosystem stability. Here, we studied multifunctional redundancy of diurnal and nocturnal ant communities in four tropical rain forest sites. We analyzed how it was influenced by species richness, functional performance, and circadian asynchrony. In two neotropical sites, species richness and functional redundancy were lower at night. In contrast, these parameters did not differ in the two paleotropical sites we studied. Circadian asynchrony between species was pronounced in the neotropical sites, and increased circadian functional redundancy. In general, species richness positively affected functional redundancy, but the effect size depended on the temporal and spatial breadth of the species with highest functional performance. Our analysis shows that high levels of trophic performance were only reached through the presence of such high- performing species, but not by even contributions of multiple, less- efficient species. Thus, these species can increase current functional performance, but reduce overall functional redundancy. Our study highlights that diurnal and nocturnal ecosystem properties of the very same habitat can markedly differ in terms of species richness and functional redundancy. Consequently, like the need to study multiple ecosystem functions, multiple periods of the circadian cycle need to be assessed in order to fully understand the diversity- stability relationship in an ecosystem. © 2016 by the Ecological Society of America.  
  Address CNRS, UMR Ecologie des Forêts de Guyane, BP 709, Kourou Cedex, France  
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  Notes Export Date: 17 February 2016 Approved no  
  Call Number EcoFoG @ webmaster @ Serial 664  
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