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Author Bardet, S.; Beauchene, J.; Thibaut, B. openurl 
  Title Influence of basic density and temperature on mechanical properties perpendicular to grain of ten wood tropical species Type Journal Article
  Year 2003 Publication Annals of Forest Science Abbreviated Journal Ann. For. Sci.  
  Volume 60 Issue 1 Pages 49-59  
  Keywords green wood; tropical wood; transverse mechanical properties; basic density; softening temperature  
  Abstract (up) The influence of temperature on transverse mechanical properties of 10 tropical species in green condition was studied in radial compression (0 to 99 degreesC), transverse shear with longitudinal-radial shearing plane and rupture of the longitudinal-tangential plane (20 to 80 degreesC). Basic density ranged from 0.21 to 0.91 g cm(-3). Load-displacement curves were characterised by initial rigidity, yield stress, yield strain and strain energy at 20% strain level. The relation between each criterion and basic density was expressed by a power law. The dependency on temperature evidenced a sharp glassy transition, except for the fracture energy only slightly influenced by temperature. An empirical model allowed evaluating a transition temperature between 51 and 69 degreesC, depending on the species and the criterion, which was attributed to lignin. Detailed analysis of the apparent modulus in radial compression suggested that complex relaxation phenomena occur around 10 degreesC and that the rubbery state is not fully reached at 80 degreesC.  
  Address Univ Montpellier 2, Lab Mecan & Genie Civil, Equipe Bois, F-34095 Montpellier 5, France  
  Corporate Author Thesis  
  Publisher E D P SCIENCES 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:000181322100006 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 275  
Permanent link to this record
 

 
Author Lebrini, M.; Robert, F.; Lecante, A.; Roos, C. openurl 
  Title Corrosion inhibition of C38 steel in 1 M hydrochloric acid medium by alkaloids extract from Oxandra asbeckii plant Type Journal Article
  Year 2011 Publication Corrosion Science Abbreviated Journal Corrosion Sci.  
  Volume 53 Issue 2 Pages 687-695  
  Keywords Steel; EIS; Polarization; Raman spectroscopy; Acid inhibition  
  Abstract (up) 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.  
  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  
  Corporate Author Thesis  
  Publisher Pergamon-Elsevier Science Ltd Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0010-938x ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000287004700021 Approved no  
  Call Number EcoFoG @ webmaster @ Serial 299  
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Author Lebrini, M.; Roos, C.; Vezin, H.; Robert, F. pdf  url
openurl 
  Title Electrochemical and theoretical studies of adsorption of some indole derivates at C38 Steel/Sulfuric acid interface as corrosion inhibitors Type Journal Article
  Year 2011 Publication International Journal of Electrochemical Science Abbreviated Journal Int.J.Electrochem.Sci.  
  Volume 6 Issue 9 Pages 3844-3857  
  Keywords Acidic media; Adsorption; C38 steel; Corrosion inhibitors; Theoretical calculations  
  Abstract (up) The inhibitive action of 9H-pyrido[3,4-b]indole (norharmane) and 1-Methyl-9H-pyrido[3,4-b]indole (harmane) on corrosion of C38 steel in 0.5 M H2SO4 solution was investigated through electrochemical techniques. The experimental results obtained revealed that these compounds inhibited the steel corrosion in acid solution for all concentrations studied. Polarization measurements indicate that the examined compounds act as a mixed inhibitor and its inhibition efficiency increases with inhibitor concentration. Data obtained from ac impedance technique show a frequency distribution and therefore a modelling element with frequency dispersion behaviour, a constant phase element (CPE), has been used. The adsorption of used compounds on the steel surface obeys Langmuir's isotherm. The ΔG°ads values were calculated and discussed for both inhibitors. Significant correlations are obtained between inhibition efficiency and quantum chemical parameters using quantitative structure-activity relationship (QSAR) method. © 2011 by ESG.  
  Address Laboratoire de Chimie Organique et Macromoléculaire, UMR-CNRS 8009, USTL BâtC4, F-59655 Villeneuve d'Ascq 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 14523981 (Issn) ISBN Medium  
  Area Expedition Conference  
  Notes Export Date: 21 October 2011; Source: Scopus; Language of Original Document: English; Correspondence Address: Robert, F.; Laboratoire Matériaux et Molécules en Milieu Amazonien, UAG-UMR ECOFOG, Campus Trou Biran, Cayenne 97337, French Guiana; email: florent.robert@guyane.univ-ag.fr Approved no  
  Call Number EcoFoG @ webmaster @ Serial 347  
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Author Céréghino, R.; Françoise, L.; Bonhomme, C.; Carrias, J.-F.; Compin, A.; Corbara, B.; Jassey, V.; Leflaive, J.; Rota, T.; Farjalla, V.; Leroy, C. doi  openurl
  Title Desiccation resistance traits predict freshwater invertebrate survival and community response to drought scenarios in a Neotropical ecosystem Type Journal Article
  Year 2020 Publication Ecological Indicators Abbreviated Journal Ecol. Indic.  
  Volume 119 Issue 106839 Pages  
  Keywords Climate change; Functional traits; Lt50; Macroinvertebrates; Rainforests; Biodiversity; Climate change; Driers (materials); Drought; Environmental management; Population statistics; Tanks (containers); Water; Aquatic invertebrates; Climate change adaptation; Controlled conditions; Environmental managers; Freshwater biodiversity; Freshwater invertebrates; Future climate scenarios; Laboratory conditions; Aquatic organisms; aquatic community; biodiversity; climate change; cuticle; desiccation; drought stress; invertebrate; Neotropical Region; population size; survival; French Guiana; Invertebrata  
  Abstract (up) The intensification of dry seasons is a major threat to freshwater biodiversity in Neotropical regions. Little is known about resistance to drying stress and the underpinning traits in Neotropical freshwater species, so we don't know whether desiccation resistance allows to anticipate shifts in biological diversity under future climate scenarios. Here, we used the aquatic invertebrates that live in the rainwater-filled leaves of tank bromeliads, to examine the extent to which desiccation resistance of species measured in the laboratory predicts community response to drought intensification in nature. We measured desiccation resistance in 17 invertebrate species (>90% of the biomass usually found in bromeliads of French Guiana) by recording the median lethal time (LT50) of experimental populations exposed to controlled conditions of residual moisture. In the field, we placed rainshelters above tank bromeliads to emulate drought scenarios ranging from the ambient norm to IPCC scenarios and extreme events, and we recorded the response of functional community structure. LT50 ranged from 4.18 to 19.06 days, and was related to cuticle content and dry body mass. Among other functional indicators that represent strategies to optimize resource use under stressful conditions (e.g., habitat use, trophic specialization), LT50 was the best predictor of community structure responses along a gradient of emulated drought intensities. Therefore, species’ LT50s measured under laboratory conditions can be used to forecast aquatic community response to drying stress in nature. Anticipating how species will cope with drought has never been more important for environmental managers to support climate change adaptation. We show that desiccation resistance in freshwater invertebrates is a key indicator of potential population size and local–global range shifts, and this could be especially true in the Neotropics where species have narrow physiological tolerances for climatic variation. © 2020 Elsevier Ltd  
  Address ECOFOG, AgroParisTech, CIRAD, CNRS, INRA, Université de Guyane, Université des Antilles, Campus Agronomique, Kourou, 97379, France  
  Corporate Author Thesis  
  Publisher Elsevier B.V. Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1470160x (Issn) ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number EcoFoG @ webmaster @ Serial 941  
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Author Schwalm, C.R.; Williams, C.A.; Schaefer, K.; Arneth, A.; Bonal, D.; Buchmann, N.; Chen, J.Q.; Law, B.E.; Lindroth, A.; Luyssaert, S.; Reichstein, M.; Richardson, A.D. openurl 
  Title Assimilation exceeds respiration sensitivity to drought: A FLUXNET synthesis Type Journal Article
  Year 2010 Publication Global Change Biology Abbreviated Journal Glob. Change Biol.  
  Volume 16 Issue 2 Pages 657-670  
  Keywords biome; carbon cycling; drought; eddy covariance; evaporative fraction; FLUXNET; synthesis  
  Abstract (up) The intensification of the hydrological cycle, with an observed and modeled increase in drought incidence and severity, underscores the need to quantify drought effects on carbon cycling and the terrestrial sink. FLUXNET, a global network of eddy covariance towers, provides dense data streams of meteorological data, and through flux partitioning and gap filling algorithms, estimates of net ecosystem productivity (F-NEP), gross ecosystem productivity (P), and ecosystem respiration (R). We analyzed the functional relationship of these three carbon fluxes relative to evaporative fraction (EF), an index of drought and site water status, using monthly data records from 238 micrometeorological tower sites distributed globally across 11 biomes. The analysis was based on relative anomalies of both EF and carbon fluxes and focused on drought episodes by biome and climatic season. Globally P was approximate to 50% more sensitive to a drought event than R. Network-wide drought-induced decreases in carbon flux averaged -16.6 and -9.3 g C m-2 month-1 for P and R, i.e., drought events induced a net decline in the terrestrial sink. However, in evergreen forests and wetlands drought was coincident with an increase in P or R during parts of the growing season. The most robust relationships between carbon flux and EF occurred during climatic spring for F-NEP and in climatic summer for P and R. Upscaling flux sensitivities to a global map showed that spatial patterns for all three carbon fluxes were linked to the distribution of croplands. Agricultural areas exhibited the highest sensitivity whereas the tropical region had minimal sensitivity to drought. Combining gridded flux sensitivities with their uncertainties and the spatial grid of FLUXNET revealed that a more robust quantification of carbon flux response to drought requires additional towers in all biomes of Africa and Asia as well as in the cropland, shrubland, savannah, and wetland biomes globally.  
  Address [Schwalm, Christopher R.; Williams, Christopher A.] Clark Univ, Grad Sch Geog, Worcester, MA 01610 USA, Email: cschwalm@clarku.edu  
  Corporate Author Thesis  
  Publisher WILEY-BLACKWELL PUBLISHING, INC Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1354-1013 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000274419400014 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 69  
Permanent link to this record
 

 
Author Paine, C.E.T.; Harms, K.E.; Schnitzer, S.A.; Carson, W.P. openurl 
  Title Weak competition among tropical tree seedlings: Implications for species coexistence Type Journal Article
  Year 2008 Publication Biotropica Abbreviated Journal Biotropica  
  Volume 40 Issue 4 Pages 432-440  
  Keywords Brosimum alicastrum; competitive irrelevance; maintenance of biodiversity; Matisia cordata; resource competition; Panama; Peru; Pouteria reticulata; zone of influence  
  Abstract (up) The intensity of competition among forest tree seedlings is poorly understood, but has important ramifications for their recruitment and for the maintenance of species diversity. Intense competition among seedlings could allow competitively dominant species to exclude subordinate species. Alternatively, the low density and small stature of forest tree seedlings could preclude intense interseedling competition. In this case, other processes, such as size-asymmetric competition with adults, interactions with consumers, or neutral dynamics would prevail as those structuring the forest understory. We tested the intensity of, and potential for, intraspecific competition among tree seedlings of three species (Brosimum alicastrum, Matisia cordata, and Pouteria reticulata) in two Neotropical rain forests. We reduced stem densities by up to 90 percent and monitored individual growth and survival rates for up to 24 mo. Individual growth and survival rates were generally unrelated to stem density. Contrary to the predicted behavior of intensely competing plant populations, the distribution of individual heights did not become more left-skewed with time for any species, regardless of plot density; i.e., excesses of short, suppressed individuals did not accumulate in high-density plots. We further measured the overlap of zones of influence (ZOIs) to assess the potential for resource competition. Seedling ZOIs overlapped only slightly in extremely dense monodominant plots, and even less in ambient-density plots of mixed composition. Our results thus suggest that interseedling competition was weak. Given the low density of tree seedlings in Neotropical forests, we infer that resource competition among seedlings may be irrelevant to their recruitment.  
  Address [Paine, C. E. Timothy; Harms, Kyle E.] Louisiana State Univ, Dept Biol Sci, Baton Rouge, LA 70803 USA, Email: cetpaine@gmail.com  
  Corporate Author Thesis  
  Publisher BLACKWELL PUBLISHING Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0006-3606 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000257717500006 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 134  
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Author Lauth, J.; Ruiz-González, M.X.; Orivel, J. pdf  url
openurl 
  Title New findings in insect fungiculture: Have ants developed non-food, agricultural products? Type Journal Article
  Year 2011 Publication Communicative & Integrative Biology Abbreviated Journal Comm & Integr Biol  
  Volume 4 Issue 1942-0889 Pages 728-730  
  Keywords  
  Abstract (up) The interaction between Allomerus plant-ants and an ascomycete fungus growing on and strengthening their galleries is not opportunistic. We previously demonstrated that this association is highly specific as only one fungal species represented by a few haplotypes was found associated with the ants. We also discovered that the ants' behavior revealed a major investment in manipulating and enhancing the growth of their associated fungus. We have growing evidence that this specificity is consistent with selection by the ants. Here, we discuss this selection within the framework of insect agriculture, as we believe these ants fulfill all of the prerequisites to be considered as farmers. Allomerus ants promote their symbiont's growth, protect it from potential pathogens and select specific cultivars. Taken together, we think that the interaction between Allomerus ants and their cultivar might represent the first case of insect fungiculture used as a means of obtaining building material.  
  Address  
  Corporate Author Thesis  
  Publisher Landes Bioscience Inc. 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 Approved no  
  Call Number EcoFoG @ webmaster @ Serial 379  
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Author Dezerald, O.; Talaga, S.; Leroy, C.; Carrias, J.-F.; Corbara, B.; Dejean, A.; Céréghino, R. url  doi
openurl 
  Title Environmental determinants of macroinvertebrate diversity in small water bodies: Insights from tank-bromeliads Type Journal Article
  Year 2014 Publication Hydrobiologia Abbreviated Journal Hydrobiologia  
  Volume 723 Issue 1 Pages 77-86  
  Keywords Freshwater biodiversity; Linear mixed effect modelling; Microcosms; Phytotelmata; Ponds  
  Abstract (up) The interlocking leaves of tank-forming bromeliads (Bromeliaceae) collect rainwater and detritus, thus creating a freshwater habitat for specialized organisms. Their abundance and the possibility of quantifying communities with accuracy give us unparalleled insight into how changes in local to regional environments influence community diversity in small water bodies. We sampled 365 bromeliads (365 invertebrate communities) along a southeastern to northwestern range in French Guiana. Geographic locality determined the species pool for bromeliad invertebrates, and local environments determined the abundance patterns through the selection of traits that are best adapted to the bromeliad habitats. Patterns in community structure mostly emerged from patterns of predator species occurrence and abundance across local-regional environments, while the set of detritivores remained constant. Water volume had a strong positive correlation with invertebrate diversity, making it a biologically relevant measure of the pools' carrying capacity. The significant effects of incoming detritus and incident light show that changes in local environments (e.g., the conversion of forest to cropping systems) strongly influence freshwater communities. Because changes in local environments do not affect detritivores and predators equally, one may expect functional shifts as sets of invertebrates with particular traits are replaced or complemented by other sets with different traits. © 2013 Springer Science+Business Media Dordrecht.  
  Address CNRS, EcoLab (UMR-CNRS 5245), 118 Route de Narbonne, 31062 Toulouse, 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 00188158 (Issn) ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number EcoFoG @ webmaster @ Serial 517  
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Author Foucaud, J.; Orivel, J.; Fournier, D.; Delabie, J.H.C.; Loiseau, A.; Le Breton, J.; Cerdan, P.; Estoup, A. openurl 
  Title Reproductive system, social organization, human disturbance and ecological dominance in native populations of the little fire ant, Wasmannia auropunctata Type Journal Article
  Year 2009 Publication Molecular Ecology Abbreviated Journal Mol. Ecol.  
  Volume 18 Issue 24 Pages 5059-5073  
  Keywords biological invasion; clonality; human disturbance; parthenogenesis; social organization; Wasmannia auropunctata  
  Abstract (up) The invasive ant species Wasmannia auropunctata displays both ecologically dominant and non-dominant populations within its native range. Three factors could theoretically explain the ecological dominance of some native populations of W. auropunctata: (i) its clonal reproductive system, through demographic and/or adaptive advantages; (ii) its unicolonial social organization, through lower intraspecific and efficient interspecific competition; (iii) the human disturbance of its native range, through the modification of biotic and abiotic environmental conditions. We used microsatellite markers and behavioural tests to uncover the reproductive modes and social organization of dominant and non-dominant native populations in natural and human-modified habitats. Microsatellite and mtDNA data indicated that dominant and non-dominant native populations (supercolonies as determined by aggression tests) of W. auropunctata did not belong to different evolutionary units. We found that the reproductive system and the social organization are neither necessary nor sufficient to explain W. auropunctata ecological dominance. Dominance rather seems to be set off by unknown ecological factors altered by human activities, as all dominant populations were recorded in human-modified habitats. The clonal reproductive system found in some populations of W. auropunctata may however indirectly contribute to its ecological dominance by allowing the species to expand its environmental niche, through the fixation over time of specific combinations of divergent male and female genotypes. Unicoloniality may rather promote the range expansion of already dominant populations than actually trigger ecological dominance. The W. auropunctata model illustrates the strong impact of human disturbance on species' ecological features and the adaptive potential of clonal reproductive systems.  
  Address [Foucaud, Julien; Fournier, Denis; Loiseau, Anne; Estoup, Arnaud] Montpellier SupAgro, Cirad, IRD, INRA,UMR CBGP, F-34988 Montferrier Sur Lez, France, Email: julien.foucaud@legs.cnrs-gif.fr  
  Corporate Author Thesis  
  Publisher WILEY-BLACKWELL PUBLISHING, INC Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0962-1083 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000272452700009 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 191  
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Author Bonal, D.; Bosc, A.; Ponton, S.; Goret, J.Y.; Burban, B.; Gross, P.; Bonnefond, J.M.; Elbers, J.; Longdoz, B.; Epron, D.; Guehl, J.M.; Granier, A. openurl 
  Title Impact of severe dry season on net ecosystem exchange in the Neotropical rainforest of French Guiana Type Journal Article
  Year 2008 Publication Global Change Biology Abbreviated Journal Glob. Change Biol.  
  Volume 14 Issue 8 Pages 1917-1933  
  Keywords dry season; ecosystem respiration; eddy covariance; gross ecosystem productivity; Neotropical rainforest; net ecosystem productivity; soil drought; solar radiation  
  Abstract (up) The lack of information on the ways seasonal drought modifies the CO2 exchange between Neotropical rainforest ecosystems and the atmosphere and the resulting carbon balance hinders our ability to precisely predict how these ecosystems will respond as global environmental changes force them to face increasingly contrasting conditions in the future. To address this issue, seasonal variations in daily net ecosystem productivity (NEPd) and two main components of this productivity, daily total ecosystem respiration (R-Ed) and daily gross ecosystem productivity (GEP(d)), were estimated over 2 years at a flux tower site in French Guiana, South America (5 degrees 16'54'N, 52 degrees 54'44'W). We compared seasonal variations between wet and dry periods and between dry periods of contrasting levels of intensity (i.e. mild vs. severe) during equivalent 93-day periods. During the wet periods, the ecosystem was almost in balance with the atmosphere (storage of 9.0 g C m(-2)). Seasonal dry periods, regardless of their severity, are associated with higher incident radiation and lower R-Ed combined with reduced soil respiration associated with low soil water availability. During the mild dry period, as is normally the case in this region, the amount of carbon stored in the ecosystem was 32.7 g C m(-2). Severe drought conditions resulted in even lower R-Ed, whereas the photosynthetic activity was only moderately reduced and no change in canopy structure was observed. Thus, the severe dry period was characterized by greater carbon storage (64.6 g C m(-2)), emphasizing that environmental conditions, such as during a severe drought, modify the CO2 exchange between Neotropical rainforest ecosystems and the atmosphere and potentially the resulting carbon balance.  
  Address [Bonal, Damien; Goret, Jean-Yves; Burban, Benoit] INRA, UMR Ecol Forets Guyane, Kourou 97387, French Guiana, Email: damien.bonal@kourou.cirad.fr  
  Corporate Author Thesis  
  Publisher BLACKWELL PUBLISHING Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1354-1013 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000257712400015 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 133  
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