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Author Ruelle, J.; Beauchene, J.; Yamamoto, H.; Thibaut, B. openurl 
  Title Variations in physical and mechanical properties between tension and opposite wood from three tropical rainforest species Type Journal Article
  Year 2011 Publication (down) Wood Science and Technology Abbreviated Journal Wood Sci. Technol.  
  Volume 45 Issue 2 Pages 339-357  
  Keywords  
  Abstract Growth strains were measured in situ in nine trees of three species from a French Guiana tropical rainforest in a clearly active verticality restoration process. The aim was to detect tension wood within the samples. Wood specimens were cut in the vicinity of the growth strain measurements in order to determine the microfibril angle and some mechanical and physical properties. As suspected, tensile growth strain was much higher in tension wood zones, as shown by the slightly higher longitudinal modulus of elasticity. Conversely, tension wood showed reduced compression strength. Longitudinal shrinkage was much higher in tension wood than in opposite wood. Clear relationships between the microfibril angle and longitudinal properties were noted in comparison (i) with those observed in gymnosperm compression wood and (ii) with expected relationships from the organization of wood fibres cell wall structure.  
  Address [Ruelle, Julien; Yamamoto, Hiroyuki] Nagoya Univ, Grad Sch Bioagr Sci, Nagoya, Aichi 4648601, Japan, Email: julien.ruelle@ecofog.gf  
  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 0043-7719 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000289477300013 Approved no  
  Call Number EcoFoG @ webmaster @ Serial 305  
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Author Bremaud, I.; Amusant, N.; Minato, K.; Gril, J.; Thibaut, B. openurl 
  Title Effect of extractives on vibrational properties of African Padauk (Pterocarpus soyauxii Taub.) Type Journal Article
  Year 2011 Publication (down) Wood Science and Technology Abbreviated Journal Wood Sci. Technol.  
  Volume 45 Issue 3 Pages 461-472  
  Keywords  
  Abstract Extractives can affect the vibrational properties tan delta (damping coefficient) and E'/rho (specific Young's modulus), but this is highly dependent on species, compounds, and cellular locations. This paper investigates such effects for African Padauk (Pterocarpus soyauxii Taub.), a tropical hardwood with high extractives content and a preferred material for xylophones. Five groups of 26 heartwood specimens with large, yet comparable, ranges in vibrational properties were extracted in different solvents. Changes in vibrational properties were set against yields of extracts and evaluation of their cellular location. Methanol (ME) reached most of the compounds (13%), located about half in lumen and half in cell-wall. Water solubility was extremely low. tan delta and E'/rho were very strongly related (R (2) a parts per thousand yen 0.93), but native wood had abnormally low values of tan delta, while extraction shifted this relation towards higher tan delta values. ME extracted heartwood became in agreement with the average of many species, and close to sapwood. Extractions increased tan delta as much as 60%, irrespective of minute moisture changes or initial properties. Apparent E'/rho was barely changed (+2% to -4%) but, after correcting the mass contribution of extracts, it was in fact slightly reduced (down to -10% for high E'/rho), and increasingly so for specimens with low initial values of E'/rho.  
  Address [Bremaud, I; Minato, K] Kyoto Prefectural Univ, Lab Forest Resource Circulating Circles, Grad Sch Life & Environm Sci, Kyoto 6068522, Japan, Email: iris_bremaud@hotmail.com  
  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 0043-7719 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000292550700005 Approved no  
  Call Number EcoFoG @ webmaster @ Serial 329  
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Author Bremaud, I.; Gril, J.; Thibaut, B. openurl 
  Title Anisotropy of wood vibrational properties: dependence on grain angle and review of literature data Type Journal Article
  Year 2011 Publication (down) Wood Science and Technology Abbreviated Journal Wood Sci. Technol.  
  Volume 45 Issue 4 Pages 735-754  
  Keywords  
  Abstract The anisotropy of vibrational properties influences the acoustic behaviour of wooden pieces and their dependence on grain angle (GA). As most pieces of wood include some GA, either for technological reasons or due to grain deviations inside trunks, predicting its repercussions would be useful. This paper aims at evaluating the variability in the anisotropy of wood vibrational properties and analysing resulting trends as a function of orientation. GA dependence is described by a model based on transformation formulas applied to complex compliances, and literature data on anisotropic vibrational properties are reviewed. Ranges of variability, as well as representative sets of viscoelastic anisotropic parameters, are defined for mean hardwoods and softwoods and for contrasted wood types. GA-dependence calculations are in close agreement with published experimental results and allow comparing the sensitivity of different woods to GA. Calculated trends in damping coefficient (tan delta) and in specific modulus of elasticity (E'/rho) allow reconstructing the general tan delta-E'/rho statistical relationships previously reported. Trends for woods with different mechanical parameters merge into a single curve if anisotropic ratios (both elastic and of damping) are correlated between them, and with axial properties, as is indicated by the collected data. On the other hand, varying damping coefficient independently results in parallel curves, which coincide with observations on chemically modified woods, either “artificially”, or by natural extractives.  
  Address [Bremaud, I; Gril, J] Univ Montpellier 2, Lab Mecan & Genie Civil, CNRS, CC048, F-34095 Montpellier 5, France, Email: iris_bremaud@hotmail.com  
  Corporate Author Thesis  
  Publisher Springer Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0043-7719 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000296006000009 Approved no  
  Call Number EcoFoG @ webmaster @ Serial 369  
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Author Aimene, Y.E.; Nairn, J.A. url  openurl
  Title Simulation of transverse wood compression using a large-deformation, hyperelastic–plastic material model Type Journal Article
  Year 2015 Publication (down) Wood Science and Technology Abbreviated Journal Wood Science and Technology  
  Volume 49 Issue 1 Pages 21-39  
  Keywords  
  Abstract Transverse compression of wood is a process that induces large deformations. The process is dominated by elastic and plastic cell wall buckling. This work reports a numerical study of the transverse compression and densification of wood using a large-deformation, elastic–plastic constitutive law. The model is isotropic, formulated within the framework of hyperelasticity, and implemented in explicit material point method (MPM) software. The model was first validated for modeling of cellular materials by compression of an isotropic cellular model specimen. Next, it was used to model compression of wood by first validating use of isotropic, transverse plane properties for tangential compression of hardwood, and then by investigating both tangential and radial compression of softwood. Importantly, the discretization of wood specimens used MPM methods to reproduce accurately the complex morphology of wood anatomy for different species. The simulations have reproduced observations of stress–strain response during wood compression including details of inhomogeneous deformation caused by variations in wood anatomy. © 2014, Springer-Verlag Berlin Heidelberg.  
  Address Wood Science and Engineering Department, Oregon State University, Corvallis, OR, United States  
  Corporate Author Thesis  
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  Notes Export Date: 27 August 2015 Approved no  
  Call Number EcoFoG @ webmaster @ Serial 617  
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Author Chang, S.-S.; Quignard, F.; Clair, B. url  doi
openurl 
  Title The effect of sectioning and ultrasonication on the mesoporosity of poplar tension wood Type Journal Article
  Year 2017 Publication (down) Wood Science and Technology Abbreviated Journal  
  Volume 51 Issue 3 Pages 507-516  
  Keywords  
  Abstract Increasing interest in understanding tension stress generation in tension wood with fibres having a gelatinous layer (G-layer) has focused attention on the specific role of this layer. To distinguish its contribution from those of other wall layers, the G-layer of wood sections was isolated by ultrasonication. The aim of this study was to assess the effect of sectioning and of the ultrasonic treatment on the mesoporosity of tension wood using nitrogen adsorption–desorption analysis. The results showed that the process of isolating the G-layer using ultrasonication strongly affects its mesoporosity. Most damage was found to occur during sectioning rather than as a result of the 15-min ultrasonic treatment.  
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  Series Volume Series Issue Edition  
  ISSN 1432-5225 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number EcoFoG @ webmaster @ Chang2017 Serial 782  
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Author Barabe, D.; Lacroix, C.; Gibernau, M. pdf  url
doi  openurl
  Title Developmental floral morphology of Syngonium in the context of the tribe Caladieae (Araceae) Type Journal Article
  Year 2012 Publication (down) Willdenowia – Annals of the Botanic Garden and Botanical Museum Berlin-Dahlem Abbreviated Journal  
  Volume 42 Issue 2 Pages 297-305  
  Keywords Aroids; Inflorescence; Phylogeny; Oxalate Crystals; Flower  
  Abstract The floral development of Syngonium angustatum is analysed in the context of a recently published molecular phylogeny of the Araceae. The initiation of discoid floral primordia occurs acropetally on the surface of the inflorescence. Female flowers, atypical bisexual flowers, sterile male flowers and male flowers are inserted on the same phyllotactic spirals on the spadix. Stamen primordia are initiated simultaneously on the periphery of more or less circular floral primordia. There are four stamens per flower (rarely three). In a synandrium, the fusion of stamens occurs very early during their developmental cycle. In some flowers one or two stamens remain free. The staminodes are also initiated on the periphery of the discoid floral primordium and their number varies from four to six. The growth of the fused staminodes will eventually form a longitudinal cavity in the centre of the mature synandrode. On the synandrodes located near the female zone, one or two staminodes remain free during development. No atypical bisexual flowers were observed on the inflorescence of Syngonium. The presence of a few calcium oxalate crystals was observed on the surface of all types of flowers. All the atypical flowers located at the base of the sterile zone corresponded to sterile male flowers and resulted from a more or less random disorganisation of the typical structure of a synandrode. In the Aroideae, free stamens or staminodes represent a plesiomorphic condition. The association of synandria and synandrodes is present in all early diverging genera of the tribe Caladieae and could represent the ancestral state. It is not clear if free stamens have evolved once or twice in the tribe Caladieae, both scenarios are possible.  
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  Call Number EcoFoG @ webmaster @ Serial 460  
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Author Lambs, L.; Bompy, F.; Imbert, D.; Corenblit, D.; Dulormne, M. pdf  url
openurl 
  Title Seawater and freshwater circulations through coastal forested wetlands on a Caribbean Island Type Journal Article
  Year 2015 Publication (down) Water Abbreviated Journal Water  
  Volume 7 Issue 8 Pages 4108-4128  
  Keywords 18O/2H stable isotope; Hydrology; Mangrove; Salinity; Swamp forest; Water level  
  Abstract Structure and composition of coastal forested wetlands are mainly controlled by local topography and soil salinity. Hydrology plays a major role in relation with tides, seaward, and freshwater inputs, landward. We report here the results of a two-year study undertaken in a coastal plain of the Guadeloupe archipelago (FWI). As elsewhere in the Caribbean islands, the study area is characterized by a micro-tidal regime and a highly seasonal climate. This work aimed at understanding groundwater dynamics and origin (seawater/freshwater) both at ecosystems and stand levels. These hydrological processes were assessed through 18O/16O and 2H/1H isotopic analyses, and from monthly monitoring of water level and soil salinity at five study sites located in mangrove (3) and swamp forest (2). Our results highlight the importance of freshwater budget imbalance during low rainfall periods. Sustained and/or delayed dry seasons cause soil salinity to rise at the mangrove/swamp forest ecotone. As current models on climate change project decreasing rainfall amounts over the inner Caribbean region, one may expect for this area an inland progression of the mangrove forest to the expense of the nearby swamp forest. © 2015 by the authors.  
  Address Geolab, UMR 6042, CNRS-Université Blaise Pascal, 4 rue Ledru, Clermont-Ferrand Cedex, France  
  Corporate Author Thesis  
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  Notes Export Date: 8 September 2015 Approved no  
  Call Number EcoFoG @ webmaster @ Serial 621  
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Author Cohen, M.C.L.; Behling, H.; Lara, R.J.; Smith, C.B.; Matos, H.R.S.; Vedel, V. openurl 
  Title Impact of sea-level and climatic changes on the Amazon coastal wetlands during the late Holocene Type Journal Article
  Year 2009 Publication (down) Vegetation History and Archaeobotany Abbreviated Journal Veg. Hist. Archaeobot.  
  Volume 18 Issue 6 Pages 425-439  
  Keywords Mangrove; Marajo Island; Pollen analysis; Sea-level  
  Abstract Wetland dynamics in northern Brazil during the Holocene were studied by pollen analysis and AMS radiocarbon dating of three cores. Near the Amazon mouth region, covered mainly by primary Amazon coastal forest and herbaceous vegetation, the pollen record indicates the dominance of mangroves between 4800 and 1100 cal yr B.P. A contraction of the mangrove area and an expansion of herbaceous and fern vegetation occurred between 1100 and 750 cal yr B.P. The period between 750 and 200 cal yr B.P. is characterized by an expansion of mangrove and a decrease in herbaceous and fern vegetation. This trend continued until the present. On Atalaia Island, the sediment core indicates a period with poor pollen preservation between 830 and 630 cal yr B.P. Between 630 and 330 cal yr B.P., mangroves expanded. Later, up to 45 cal yr B.P., the mangrove area decreased and the herbaceous vegetation expanded. During the last hundred years, the relative sea-level rise most probably favored the mangrove expansion as far as the topographically highest sector on this island, while the herbaceous vegetation decreased. The pollen data from Agua Preta Lake indicate dry conditions, as reflected by the poor pollen preservation between 390 and 240 cal yr B.P. Between 240 and 60 cal yr B.P., restinga and Amazon coastal forest with palms dominated this region. For the last 120 years, the record indicates an expansion of the mangrove area. However, recent confinement of mangrove development to the topographically highest area, and the loss of mangrove areas on the lowest surfaces have led to a net loss of mangrove coverage during the last decades.  
  Address [Lisboa Cohen, Marcelo Cancela; Smith, Clarisse Beltrao; Soares Matos, Hellen Rosy] Fed Univ Para, Postgrad Program Geol & Geochem, Lab Coastal Dynam, BR-66077530 Belem, PA, Brazil, Email: mcohen@ufpa.br  
  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 0939-6314 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000271191800001 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 193  
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Author Talaga, S.; Dezerald, O.; Carteron, A.; Leroy, C.; Carrias, J.-F.; Céréghino, R.; Dejean, A. url  doi
openurl 
  Title Urbanization impacts the taxonomic and functional structure of aquatic macroinvertebrate communities in a small Neotropical city Type Journal Article
  Year 2017 Publication (down) Urban Ecosystems Abbreviated Journal Urban Ecosystems  
  Volume 20 Issue 5 Pages 1001-1009  
  Keywords Aedes aegypti; Bioindicator; Diversity; Functional traits; Tank bromeliads; Urban ecology  
  Abstract Due to habitat fragmentation, resource disruption and pollution, urbanization is one of the most destructive forms of anthropization affecting ecosystems worldwide. Generally, human-mediated perturbations dramatically alter species diversity in urban sites compared to the surroundings, thus influencing the functioning of the entire ecosystem. We investigated the taxonomic and functional diversity patterns of the aquatic macroinvertebrate communities in tank bromeliads by comparing those found in a small Neotropical city with those from an adjacent rural site. Changes in the quality of detrital inputs in relation to lower tree diversity and the presence of synanthropic species are likely important driving forces behind the observed structural changes in the urban site. Leaf-litter processors (i.e., shredders, scrapers) were positively affected in the urban site, while filter-feeders that process smaller particles produced by the activity of the shredders were negatively affected. Because we cannot ascertain whether the decline in filter-feeders is related to food web-mediated effects or to competitive exclusion (Aedes aegypti mosquitoes were present in urban bromeliads only), further studies are necessary to account for the effects of intra-guild competition or inter-guild facilitation. © 2017, Springer Science+Business Media New York.  
  Address Ecolab, Université de Toulouse, CNRS, INPT, UPS, Toulouse, France  
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  Notes Cited By :1; Export Date: 18 December 2017 Approved no  
  Call Number EcoFoG @ webmaster @ Serial 776  
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Author Pétillon, J.; Leroy, B.; Djoudi, E.A.; Vedel, V. url  doi
openurl 
  Title Small and large spatial scale coexistence of ctenid spiders in a neotropical forest (French Guiana) Type Journal Article
  Year 2018 Publication (down) Tropical Zoology Abbreviated Journal  
  Volume 31 Issue 2 Pages 85-98  
  Keywords Araneae; flooding; Guianese shield; inselberg; juveniles  
  Abstract While spiders constitute the most abundant and diverse arthropods in many habitats, they remained under-studied, especially in tropical rainforests. The goal of this study is to assess the spatial distribution of the spider family Ctenidae by assessing associations of species diversity and population traits among different habitat conditions. Fieldwork was carried out during 2013 in habitats varying in flooding frequency (plateau vs. flooded forest) and elevation (inselberg vs. lowland) in the Nouragues National Natural Reserve, French Guiana. Assemblage composition, population structure, and trait measurements of one dominant species were assessed using hand collection in replicated quadrats. We found strong effects on ctenid assemblages attributable to both elevation and flooding, with changes in relative abundance of species among habitats, but few correlated densities between species. At the population level, main differences in species distribution between and within habitats were detected only when juveniles were taken into account. No effect of elevation was found on the measurements of traits of the dominant species, but legs were proportionally shorter in flooded habitats, suggesting reduced active dispersal in these habitats. Our study highlights the value of complementary of measures of diversity and traits at different biological scales in Ctenidae.  
  Address UMR CNRS 8175 Ecologie des Forêts de Guyane, Université Antilles-Guyane, Kourou Cedex, Guyane Française, France  
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  Notes Export Date: 23 April 2018 Approved no  
  Call Number EcoFoG @ webmaster @ Serial 800  
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