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Author Bréchet, Laëtitia M.; Daniel Warren; Stahl, Clément; Burban, Benoït; Goret, Jean-Yves; Salomon, Roberto L.; Janssens, Ivan A.o doi  openurl
  Title Simultaéneous tree stem and soil greenhouse gas (CO2, CH4, N2O) flux measurements: a novel design for continuous monitoring towards improving flux estimates and temporal resolution Type Journal Article
  Year 2021 Publication New Phytologist Abbreviated Journal  
  Volume 230 Issue 6 Pages 2487-2500  
  Keywords (down) système de chambre automatisé ; efflux de dioxyde de carbone ; flux de méthane ; flux d'oxyde nitreux ; tige d'arbre ; forêt tropicale  
  Abstract Tree stems and soils can act as sources and sinks for the greenhouse gases (GHG) carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O). Since both uptake and emission capacities can be large, especially in tropical rainforests, accurate assessments of the magnitudes and temporal variations of stem and soil GHG fluxes are required. We designed a new flexible stem chamber system for continuously measuring GHG fluxes in a French Guianese rainforest. Here, we describe this new system, which is connected to an automated soil GHG flux system, and discuss measurement uncertainty and potential error sources. In line with findings for soil GHG flux estimates, we demonstrated that lengthening the stem chamber closure time was required for accurate estimates of tree stem CH4 and N2O flux but not tree stem CO2 flux. The instrumented stem was a net source of CO2 and CH4 and a weak sink of N2O. Our experimental setup operated successfully in situ and provided continuous tree and soil GHG measurements at a high temporal resolution over an 11-month period. This automated system is a major step forward in the measurement of GHG fluxes in stems and the atmosphere concurrently with soil GHG fluxes in tropical forest ecosystems.  
  Address  
  Corporate Author Thesis  
  Publisher New Phytologist Foundation 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 1004  
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Author Marti, G.; Eparvier, V.; Moretti, C.; Prado, S.; Grellier, P.; Hue, N.; Thoison, O.; Delpech, B.; Gueritte, F.; Litaudon, M. openurl 
  Title Antiplasmodial benzophenone derivatives from the root barks of Symphonia globulifera (Clusiaceae) Type Journal Article
  Year 2010 Publication Phytochemistry Abbreviated Journal Phytochemistry  
  Volume 71 Issue 8-9 Pages 964-974  
  Keywords (down) Symphonia globulifera; Clusiaceae; Benzophenone; Symphonone; Antiplasmodial; LC/ESI-MS  
  Abstract In an effort to find antimalarial drugs, a systematic in vitro evaluation on a chloroquine-resistant strain of Plasmodium falciparum (FcB1) was undertaken on sixty plant extracts collected in French Guiana. The ethyl acetate extract obtained from the root barks of Symphonia globulifera exhibited a strong antiplasmodial activity (97% at 10 μg/ml). The phytochemical investigation of this extract led to the isolation of nine polycyclic polyprenylated acylphloroglucinol (PPAPs) compounds and two oxidized derivatives. All compounds showed antiplasmodial activity with IC(50)s ranged from 2.1 to 10.1 μM. A LC/ESI-MSn study performed on polyprenylated benzophenones previously isolated from Moronobea coccinea provided a reliable method for their detection in the extract and structural elucidation. (C) 2010 Elsevier Ltd. All rights reserved.  
  Address [Marti, Guillaume; Hue, Nathalie; Thoison, Odile; Delpech, Bernard; Gueritte, Francoise; Litaudon, Marc] CNRS, Inst Chim Subst Nat, Ctr Rech Gif, F-91198 Gif Sur Yvette, France, Email: marc.litaudon@icsn.cnrs-gif.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 0031-9422 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000279077400016 Approved no  
  Call Number EcoFoG @ webmaster @ Serial 284  
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Author Lebrini, M.; Robert, F.; Vezin, H.; Roos, C. openurl 
  Title Electrochemical and quantum chemical studies of some indole derivatives as corrosion inhibitors for C38 steel in molar hydrochloric acid Type Journal Article
  Year 2010 Publication Corrosion Science Abbreviated Journal Corrosion Sci.  
  Volume 52 Issue 10 Pages 3367-3376  
  Keywords (down) Steel; EIS; Raman spectroscopy; Polarization; Acid inhibition  
  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.  
  Address [Robert, F.; 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:000281315500026 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 44  
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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 (down) Steel; EIS; Polarization; Raman spectroscopy; Acid inhibition  
  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.  
  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 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. openurl 
  Title Root exclusion through trenching does not affect the isotopic composition of soil CO2 efflux Type Journal Article
  Year 2009 Publication Plant and Soil Abbreviated Journal Plant Soil  
  Volume 319 Issue 1-2 Pages 1-13  
  Keywords (down) Stable carbon isotopes; Natural abundance; Soil respiration; Trenched plot; Rainforest; Temperate forest  
  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.  
  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  
  Corporate Author Thesis  
  Publisher SPRINGER Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0032-079X ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000266143400001 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 203  
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Author Strasburg, J.L.; Scotti-Saintagne, C.; Scotti, I.; Lai, Z.; Rieseberg, L.H. openurl 
  Title Genomic Patterns of Adaptive Divergence between Chromosomally Differentiated Sunflower Species Type Journal Article
  Year 2009 Publication Molecular Biology and Evolution Abbreviated Journal Mol. Biol. Evol.  
  Volume 26 Issue 6 Pages 1341-1355  
  Keywords (down) species boundaries; chromosomal rearrangements; positive selection; hybridization; sunflowers; Helianthus  
  Abstract Understanding the genetic mechanisms of speciation and basis of species differences is among the most important challenges in evolutionary biology. Two questions of particular interest are what roles divergent selection and chromosomal differentiation play in these processes. A number of recently proposed theories argue that chromosomal rearrangements can facilitate the development and maintenance of reproductive isolation and species differences by suppressing recombination within rearranged regions. Reduced recombination permits the accumulation of alleles contributing to isolation and adaptive differentiation and protects existing differences from the homogenizing effects of introgression between incipient species. Here, we examine patterns of genetic diversity and divergence in rearranged versus collinear regions in two widespread, extensively hybridizing sunflower species, Helianthus annuus and Helianthus petiolaris, using sequence data from 77 loci distributed throughout the genomes of the two species. We find weak evidence for increased genetic divergence near chromosomal break points but not within rearranged regions overall. We find no evidence for increased rates of adaptive divergence on rearranged chromosomes; in fact, collinear chromosomes show a far greater excess of fixed amino acid differences between the two species. A comparison with a third sunflower species indicates that much of the nonsynonymous divergence between H. annuus and H. petiolaris probably occurred during or soon after their formation. Our results suggest a limited role for chromosomal rearrangements in genetic divergence, but they do document substantial adaptive divergence and provide further evidence of how species integrity and genetic identity can be maintained at many loci in the face of extensive hybridization and gene flow.  
  Address [Strasburg, Jared L.; Scotti-Saintagne, Caroline; Rieseberg, Loren H.] Indiana Univ, Dept Biol, Bloomington, IN 47405 USA, Email: jstrasbu@indiana.edu  
  Corporate Author Thesis  
  Publisher OXFORD UNIV PRESS Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0737-4038 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000266116500012 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 111  
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Author Vincent, G.; Molino, J.F.; Marescot, L.; Barkaoui, K.; Sabatier, D.; Freycon, V.; Roelens, J.B. openurl 
  Title The relative importance of dispersal limitation and habitat preference in shaping spatial distribution of saplings in a tropical moist forest: a case study along a combination of hydromorphic and canopy disturbance gradients Type Journal Article
  Year 2011 Publication Annals of Forest Science Abbreviated Journal Ann. For. Sci.  
  Volume 68 Issue 2 Pages 357-370  
  Keywords (down) Species assemblage; Dispersal limitation; Tropical moist forest; Niche  
  Abstract Various processes contribute to shaping the local assemblage of species in hyperdiverse tropical forest. The relative contribution of environmental factors and dispersal limitation in determining the spatial distribution of saplings at local scale is unclear. We examined two types of environmental factors: (a) soil type reflecting drainage regime and (b) past logging damages reflecting light regime in a neotropical moist forest site. We used a logistic model to predict presence or absence of a given species in a network of elementary small plots. The effect of mapped environmental factors and a spatial correlation term were jointly estimated providing a direct measure of the relative role of habitat specialisation and dispersal limitation. At community level, dispersal limitation was the most important determinant of species absence at local scale. The two environmental factors examined played a balanced role. Different species however showed different degrees of dispersal limitation and habitat specialisation. The distribution of a large proportion of species-the majority of the most abundant species-was significantly affected by at least one environmental factor. We provide a ranking of 49 species sensitive to canopy disturbance (from shade specialist to pioneer) and 41 species affected by seasonal flooding (either positively or negatively).  
  Address [Vincent, Gregoire; Marescot, Lucile; Barkaoui, Karim] IRD, Unite Mixte Rech AMAP, Kourou 97387, French Guiana, Email: gregoire.vincent@ird.fr  
  Corporate Author Thesis  
  Publisher Springer France 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:000290448000014 Approved no  
  Call Number EcoFoG @ webmaster @ Serial 318  
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Author Lormée, Hervé ; Berzins, Rachel ; Rocheteau, Vincent ; De Coster, Fran ; Denis, Thomas ; Richard-Hanssen, Cécile doi  openurl
  Title Seasonal Variation in the Home Ranges of Black Curassow, Crax alector, in French Guiana Type Journal Article
  Year 2021 Publication Tropical Conservation Science Abbreviated Journal  
  Volume 14 Issue 1 Pages 1-10  
  Keywords (down) spatial ecology, Cracids, tracking, Kernel method, Home range, movement pattern  
  Abstract Cracidae is the most threatened avian family in the Neotropics, mainly because of habitat destruction, heavy hunting pressure and poaching. In French Guiana, Black Curassows are heavily hunted, although basic knowledge of the ecological and demographical traits of the species remains limited. Such a gap prevents any attempt to assess the impact of hunting and to help stakeholders to develop proposals ensuring hunting sustainability. The spatial relationship between animals and their habitat is important for conservation management, being related to population densities through complex patterns. Here, we report on a radio-tracking study of Black Curassows in tropical primary rainforest, in Nouragues National Reserve, French Guiana. The aims of the study were to estimate home range size and its variation across seasons, and to quantify movement patterns of the birds. We captured and fitted VHF tags to four adults, and tracked them for 10 to 21.5 months. Daily movements were recorded, and home ranges estimated using the Kernel Density method, for two consecutive wet seasons and one dry season. Using 95% and 50% Kernel densities, the average annual home range and core area were 96.3± 32.6 ha (SE) and 22.8 ± 2.8 ha respectively. Home ranges appeared spatially stable over the two years, and overlapped between neighbouring groups. During the dry season, Black Curassows did not migrate but tended to enlarge their home range, with greater daily movements and higher home range overlap. Although additional data are still needed, our results can help to improve the knowledge and management of this poorly studied species  
  Address  
  Corporate Author Thesis  
  Publisher SAGE 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 1036  
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Author Schimann, H.; Ponton, S.; Hattenschwiler, S.; Ferry, B.; Lensi, R.; Domenach, A.M.; Roggy, J.C. openurl 
  Title Differing nitrogen use strategies of two tropical rainforest late successional tree species in French Guiana: Evidence from N-15 natural abundance and microbial activities Type Journal Article
  Year 2008 Publication Soil Biology & Biochemistry Abbreviated Journal Soil Biol. Biochem.  
  Volume 40 Issue 2 Pages 487-494  
  Keywords (down) soil; litter; nitrate; nitrification; tree rooting; N-15; Eperua falcata; Dicorynia guianensis; tropical forest  
  Abstract Previous studies in lowland tropical rainforests of French Guiana showed that, among non-N-2-fixing trees, two groups of late successional species contrasting in their leaf N-15 natural abundance coexist, suggesting two different main ways of nitrogen acquisition. Two abundant late-successional species typically co-occurring in rainforests in French Guiana, namely Eperua falcata and Dicorynia guianensis, were chosen as representative of each group. Stable isotope techniques and measurements of potentials of microbial N transformation were performed to assess to what extent leaf N-15 natural abundance of these species could be related to (i) delta N-15 signatures of soil mineral N sources and (ii) the capacity of soil to express nitrification and denitrification (both processes being directly involved in the balance between NH4+ and NO3-). Soil delta N-15-NH4+ was roughly similar to leaf delta N-15 of D. guianensis (around 3.5 parts per thousand), suggesting a preferential use of NH4+, whereas in E. falcata, leaf delta N-15 values were closer to root delta N-15-NO3- values (0.2 and -2.0 parts per thousand, respectively), suggesting a preferential use of NO3-. These differences in N source utilization were not accompanied by differences in availability in soil NO3- or in intensity of microbial functions responsible for soil N mineral evolution. However, (i) under both tree species, these functions showed clear spatial partitioning, with denitrification occurring potentially in soil and nitrification in the litter layer, and (ii) E falcata fine roots colonized the litter layer much more strongly than D. guianensis fine roots. This strongly suggests that (i) the contrasted leaf delta N-15 values found in the two late-successional species reveal distinct N acquisition strategies and (ii) the ability of roots to predominantly exploit the litter layer (E falcata) or the soil (D. guianensis) may constitute an important explanation of the observed differences. A complementarity between tree species, based on mineral N resource partitioning (itself resulting from a spatially structured location of the microbial functions responsible for the balance between NH4+ and NO3-), n thus be supposed. (c) 2007 Elsevier Ltd. All rights reserved.  
  Address [Schimann, Heidy; Ponton, Stephane; Domenach, Anne-Marie; Roggy, Jean-Christophe] UMR Ecol Forets Guyane, F-97387 Kourou, French Guiana, Email: heidy_schimann@cirad.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 0038-0717 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000251655800021 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 146  
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Author Conte, D.E.; Aboulaich, A.; Robert, F.; Olivier-Fourcade, J.; Jumas, J.C.; Jordy, C.; Willmann, P. openurl 
  Title Sn-x[BPO4](1-x) composites as negative electrodes for lithium ion cells: Comparison with amorphous SnB0.6P0.4O2.9 and effect of composition Type Journal Article
  Year 2010 Publication Journal of Solid State Chemistry Abbreviated Journal J. Solid State Chem.  
  Volume 183 Issue 1 Pages 65-75  
  Keywords (down) Sn-based composites; Lithium-ion batteries; Negative electrodes; Mossbauer spectroscopy; LixSn alloys  
  Abstract A comparative study of two Sn-based composite materials as negative electrode for Li-ion accumulators is presented. The former SnB0.6P0.4O2.9 obtained by in-situ dispersion of SnO in an oxide matrix is shown to be an amorphous tin composite oxide (ATCO). The latter Sn-0.72[BPO4](0.28) obtained by ex-situ dispersion of Sri in a borophosphate matrix consists of Sri particles embedded in a crystalline BPO4 matrix. The electrochemical responses of ATCO and Sn-0.72.[BPO4](0.28) composite in galvanostatic mode show reversible capacities of about 450 and 530 mAhg(-1), respectively, with different irreversible capacities (60% and 29%). Analysis of these composite materials by Sn-119 Mossbauer spectroscopy in transmission (TMS) and emission (CEMS) modes confirms that ATCO is an amorphous Sn-II composite oxide and shows that in the case of Sn-0.72[BPO4](0.28), the Surface of the tin clusters is mainly formed by Sn-II in an amorphous interface whereas the bulk of the clusters is mainly formed by Sn-0. The determination of the recoilless free fractions f (Lamb-Mossbauer factors) leads to the effective fraction of both Sn-0 and Sn-II species in such composites. The influence of chemical composition and especially of the surface-to-bulk tin species ratio oil the electrochemical behaviour has been analysed for several Sn-x[BPO4](1-x) composite materials (0.17 < x < 0.91). The cell using the compound Sn-0.72[BPO4](0.28) as active material exhibits interesting electrochemical performances (reversible capacity of 500 mAh g(-1) at C/5 rate). (C) 2009 Elsevier Inc. All rights reserved.  
  Address [Conte, Donato Ercole; Aboulaich, Abdelmaula; Robert, Florent; Olivier-Fourcade, Josette; Jumas, Jean-Claude] Univ Montpellier 2, CNRS, UMR 5253,Inst Charles Gerhardt, Equipe Agregats Interfaces & Mat Energie, F-34095 Montpellier, France, Email: iguanasornione@libero.it  
  Corporate Author Thesis  
  Publisher ACADEMIC PRESS INC ELSEVIER SCIENCE Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0022-4596 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000273834600010 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 83  
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