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Author Almeras, T.; Thibaut, A.; Gril, J. openurl 
  Title Effect of circumferential heterogeneity of wood maturation strain, modulus of elasticity and radial growth on the regulation of stem orientation in trees Type Journal Article
  Year 2005 Publication Trees-Structure and Function Abbreviated Journal Trees-Struct. Funct.  
  Volume 19 Issue 4 Pages 457-467  
  Keywords biomechanics; reaction wood; maturation strain; Young's modulus; eccentricity  
  Abstract Active mechanisms of re-orientation are necessary to maintain the verticality of tree stems. They are achieved through the production of reaction wood, associated with circumferential variations of three factors related to cambial activity: maturation strain, longitudinal modulus of elasticity (MOE) and eccentric growth. These factors were measured on 17 mature trees from different botanical families and geographical locations. Various patterns of circumferential variation of these factors were identified. A biomechanical analysis based on beam theory was performed to quantify the individual impact of each factor. The main factor of re-orientation is the circumferential variation of maturation strains. However, this factor alone explains only 57% of the re-orientations. Other factors also have an effect through their interaction with maturation strains. Eccentric growth is generally associated with heterogeneity of maturation strains, and has an important complementary role, by increasing the width of wood with high maturation strain. Without this factor, the efficiency of re-orientations would be reduced by 31% for angiosperms and 26% for gymnosperms. In the case of angiosperms, MOE is often larger in tension wood than in normal wood. Without these variations, the efficiency of re-orientations would be reduced by 13%. In the case of gymnosperm trees, MOE of compression wood is lower than that of normal wood, so that re-orientation efficiency would be increased by 24% without this factor of variations.  
  Address Nagoya Univ, Lab Biomat Phys, Dept Bioagr Sci, Nagoya, Aichi 4648601, Japan, Email: t_almeras@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 (down) 0931-1890 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000229890700012 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 253  
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Author Schimann, H.; Joffre, R.; Roggy, J.C.; Lensi, R.; Domenach, A.M. openurl 
  Title Evaluation of the recovery of microbial functions during soil restoration using near-infrared spectroscopy Type Journal Article
  Year 2007 Publication Applied Soil Ecology Abbreviated Journal Appl. Soil Ecol.  
  Volume 37 Issue 3 Pages 223-232  
  Keywords NIRS; microbial activities; respiration; denitrification; carbon; nitrogen; soil functioning; restoration  
  Abstract Microbial-based indicators, such as C and N contents or microbial functions involved in C and N cycles, are currently used to describe the status of soils in disturbed areas. Microbial functions are more accurate indicators but their measurement for studies at the ecosystem level remains problematical because of the huge spatial variability of these processes and, consequently, of the large number of soil samples which must be analyzed. Our goal was to test the capacity of near-infrared reflectance spectroscopy (NIRS) to predict respiration and denitrification but also carbon and nitrogen contents of soils submitted to various procedures of restoration. To achieve this objective, we took advantage of an experiment conducted on a reforestation system established after open-cast gold mining in French Guiana. In this experimental station, plantations of various ages and various soil textures were at our disposal. Our results showed that both plantations and soil texture had a strong impact on the recovery of soil functioning: carbon and nitrogen contents, respiration and denitrification increased with age of plantation and clay content. Calibrations were performed between spectral data and microbial-based indicators using partial least squares regression (PLS). The results showed that C and N contents were accurately predicted. Microbial functions were less precisely predicted with results more accurate on clayey soils than on sandy soils. In clayey soils, perturbed or restored soils and the year of plantation were discriminated very efficiently through principal component analyses of spectral signatures (over 80% of variance explained on the first two axes). Near-infrared spectroscopy may thus be extended to the prediction of functional soil parameters, but the capacity of this method must be strengthened by expending the databases with other soils in other contexts. The possibility of using NIRS provides many opportunities for understanding both the temporal dynamics and the spatial variability of the recovery of key microbial functions during soil restoration. (c) 2007 Elsevier B.V. All rights reserved.  
  Address UMR EcoFoG, Kourou 97387, French Guiana, Email: heidy.schimann@cirad.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 (down) 0929-1393 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000250668000006 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 154  
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Author Maggia, Marie-Eugénie ; Decaëns, Thibaud ; Lapied, Emmanuel ; Dupont, Lise ; Roy, Virginie ; Schimann, Heidy ; Orivel, Jérome ; Murienne, Jérôme ; Baraloto, Christophier ; Cottenie, Karl ; Steinke, Dirk doi  openurl
  Title At each site its diversity: DNA barcoding reveals remarkable earthworm diversity in neotropical rainforests of French Guiana Type Journal Article
  Year 2021 Publication Applied Soil Ecology Abbreviated Journal  
  Volume 164 Issue Pages 103932  
  Keywords DNA barcoding Tropical rainforest Community ecology Diversity level Sampling methods  
  Abstract Despite their recognized essential role in soil, earthworms in tropical environments are still understudied. The aim of this study was to re-evaluate the diversity at the regional scale, as well as to investigate the environmental and spatial drivers of earthworm communities. We sampled earthworm communities across a range of habitats at six localities in French Guiana using three different sampling methods. We generated 1675 DNA barcodes and combined them with data from a previous study. Together, all sequences clustered into 119 MOTUs which were used as proxy to assess species richness. Only two MOTUs were common between the six localities and 20.2% were singletons, showing very high regional species richness and a high number of rare species. A canonical redundancy analysis was used to identify key drivers of the earthworm community composition. The RDA results and beta-diversity calculations both show strong species turnover and a strong spatial effect, resulting from dispersal limitations that are responsible for the current community composition. Sampling in different microhabitats allowed the discovery of 23 MOTUs that are exclusively found in decaying trunks and epiphytes, highlighting hidden diversity of earthworms outside of soil.  
  Address  
  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 (down) 0929-1393 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number EcoFoG @ webmaster @ Serial 1055  
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Author Bodin, S.C.; Scheel-Ybert, R.; Beauchene, J.; Molino, J.-F.; Bremond, L. url  doi
openurl 
  Title CharKey: An electronic identification key for wood charcoals of French Guiana Type Journal Article
  Year 2019 Publication IAWA Journal Abbreviated Journal Iawa J.  
  Volume 40 Issue 1 Pages 75-91  
  Keywords anthracology; Charcoal anatomy; computeraided identification; Note: Supplementary material can be accessed in the online edition of this journal via brill.com/iawa.; tropical flora; Xper 2  
  Abstract Tropical tree floras are highly diverse and many genera and species share similar anatomical patterns, making the identification of tropical wood charcoal very difficult. Appropriate tools to characterize charcoal anatomy are thus needed to facilitate and improve identification in such species-rich areas. This paper presents the first computer-aided identification key designed for charcoals from French Guiana, based on the wood anatomy of 507 species belonging to 274 genera and 71 families, which covers respectively 28%, 67% and 86% of the tree species, genera and families currently listed in this part of Amazonia. Species of the same genus are recorded together except those described under a synonym genus in Détienne et al. (1982) that were kept separately. As a result, the key contains 289 'items' and mostly aims to identify charcoals at the genus level. It records 26 anatomical features leading to 112 feature states, almost all of which are illustrated by SEM photographs of charcoal. The descriptions were mostly taken from Détienne et al.'s guidebook on tropical woods of French Guiana (1982) and follow the IAWA list of microscopic features for hardwood identification (Wheeler et al. 1989). Some adjustments were made to a few features and those that are unrelated to charcoal identification were excluded. The whole tool, named CharKey, contains the key itself and the associated database including photographs. It can be downloaded on Figshare at https://figshare.com/s/d7d40060b53d2ad60389 (doi: 10.6084/m9.figshare.6396005). CharKey is accessible using the free software Xper 2 , specifically conceived for taxonomic description and computer aided-identification.  
  Address Ecole Pratique des Hautes Etudes, PSL Research University, Paris, France  
  Corporate Author Thesis  
  Publisher Brill Academic Publishers Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (down) 09281541 (Issn) ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number EcoFoG @ webmaster @ Serial 864  
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Author Ruelle, J.; Clair, B.; Beauchene, J.; Prevost, M.F.; Fournier, M. openurl 
  Title Tension wood and opposite wood in 21 tropical rain forest species 2. Comparison of some anatomical and ultrastructural criteria Type Journal Article
  Year 2006 Publication IAWA Journal Abbreviated Journal IAWA J.  
  Volume 27 Issue 4 Pages 341-376  
  Keywords tension wood; opposite wood; tropical rain forest; vessels; wood anatomy; wood fibre  
  Abstract The anatomy of tension wood and opposite wood was compared in 21 tropical rain forest trees from 21 species belonging to 18 families from French Guyana. Wood specimens were taken from the upper and lower sides of naturally tilted trees. Measurement of the growth stress level ensured that the two samples were taken from wood tissues in a different mechanical state: highly tensile-stressed wood on the upper side, called tension wood and normally tensile-stressed wood on the lower side, called opposite wood. Quantitative parameters relating to fibres and vessels were measured on transverse sections of both tension and opposite wood to check if certain criteria can easily discriminate the two kinds of wood. We observed a decrease in the frequency of vessels in the tension wood in all the trees studied. Other criteria concerning shape and surface area of the vessels, fibre diameter or cell wall thickness did not reveal any general trend. At the ultrastructural level, we observed that the microfibril angle in the tension wood sample was lower than in opposite wood in all the trees except one (Licania membranacea).  
  Address UAG, ENGREF,UMR Ecol Forets Guyane, INRA,ECOFOG, CIRAD,CNRS, F-97379 Kourou, Guyana, Email: ruelle_j@kourou.cirad.fr  
  Corporate Author Thesis  
  Publisher INT ASSOC WOOD ANATOMISTS Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (down) 0928-1541 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000242437400001 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 171  
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Author Clair, B.; Ruelle, J.; Beauchene, J.; Prevost, M.F.; Fournier, M. openurl 
  Title Tension wood and opposite wood in 21 tropical rain forest species 1. Occurrence and efficiency of the G-layer Type Journal Article
  Year 2006 Publication IAWA Journal Abbreviated Journal IAWA J.  
  Volume 27 Issue 3 Pages 329-338  
  Keywords gelatinous layer; G-layer; French Guyana; tropical rain forest; tension wood; wood anatomy  
  Abstract Wood samples were taken from the upper and lower sides of 21 naturally tilted trees from 18 families of angiosperms in the tropical rain forest in French Guyana. The measurement of growth stresses ensured that the two samples were taken from wood tissues in a different mechanical state: highly tensile stressed wood on the upper side, called tension wood, and lower tensile stressed wood on the lower side, called opposite wood. Eight species had tension wood fibres with a distinct gelatinous layer (G-layer). The distribution of gelatinous fibres varied from species to species. One of the species, Casearia javitensis (Flacourtiaceae), showed a peculiar multilayered secondary wall in its reaction wood. Comparison between the stress level and the occurrence of the G-layer indicates that the G-layer is not a key factor in the production of high tensile stressed wood.  
  Address UAG, INRA, ENGREF, CIRAD CNRS,ECOFOG,UMR Ecol Forets Guyane, F-97379 Kourou, Guyana, Email: clair@lmgc.univ-montp2.fr  
  Corporate Author Thesis  
  Publisher INT ASSOC WOOD ANATOMISTS Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (down) 0928-1541 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000240542400008 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 176  
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Author Clair, B.; Gril, J.; Baba, K.; Thibaut, B.; Sugiyama, J. openurl 
  Title Precautions for the structural analysis of the gelatinous layer in tension wood Type Journal Article
  Year 2005 Publication IAWA Journal Abbreviated Journal IAWA J.  
  Volume 26 Issue 2 Pages 189-195  
  Keywords artefact; fibre wall; gelatinous layer (G-layer); tension wood  
  Abstract The gelatinous layer (G-layer) of tension wood fibres in hardwood contributes to the mechanical function of the living tree and has significant consequences on properties of solid wood. Its size, shape and structure observed by optical or electron microscopy exhibits characteristic anatomical features. However, we found that sectioning of non-embedded wood samples results in an uncontrolled swelling of the G-layer. In order to assess this artefact, the shape and thickness of the G-layer was monitored by serial sections from an embedded wood sample, from its trimmed transverse face to that located several hundreds of micrometres deep. The results revealed that the initial cutting before embedding produced a border effect responsible for the swollen nature, which is similar to sections from non-embedded material. After a conventional embedding technique was applied, a section of at least 30 micrometres below the trimming surface is required to observe an un-swollen G-layer.  
  Address Kyoto Univ, Res Inst Sustainable Humanosphere, Lab Biomass Morphogenesis & Informat, Kyoto 6110011, Japan, Email: clair@blmgc.univ.montp2.fr  
  Corporate Author Thesis  
  Publisher INT ASSOC WOOD ANATOMISTS Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (down) 0928-1541 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000229698100003 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 254  
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Author Clair, B.; Arinero, R.; Leveque, G.; Ramonda, M.; Thibaut, B. openurl 
  Title Imaging the mechanical properties of wood cell wall layers by atomic force modulation microscopy Type Journal Article
  Year 2003 Publication IAWA Journal Abbreviated Journal IAWA J.  
  Volume 24 Issue 3 Pages 223-230  
  Keywords wood; cell wall; mechanical properties; elastic modulus; tension wood  
  Abstract Atomic Force Microscopy in force modulation mode was used to study the elastic properties of the different fibre wall layers of the tension wood of holm oak and normal wood of boco. The method is based on the measurement of the resonance frequency of the microscope lever in contact with the sample. This frequency is related to the reduced Young modulus E* = E/(1-nu(2)) of the material, supposed to be isotropic. 'Elastic' images of the cell are obtained simultaneously with the topographic images, which allows the observation of the mechanical properties of the cells at a nanometric scale. Layers G, S-1, S-2 and ML can clearly be distinguished. By comparison with known materials an estimation of the absolute modulus is given in the range 5-20 GPa, but should be considered with caution, because the inherent anisotropy of the materials has not been taken into account.  
  Address Univ Montpellier 2, CNRS, UMR 5508, Lab Mecan & Genie Civil, F-34095 Montpellier, France  
  Corporate Author Thesis  
  Publisher INT ASSOC WOOD ANATOMISTS Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (down) 0928-1541 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000185049700003 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 270  
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Author Kiaer, L.P.; Felber, F.; Flavell, A.; Guadagnuolo, R.; Guiatti, D.; Hauser, T.P.; Olivieri, A.M.; Scotti, I.; Syed, N.; Vischi, M.; van de Wiel, C.; Jorgensen, R.B. openurl 
  Title Spontaneous gene flow and population structure in wild and cultivated chicory, Cichorium intybus L Type Journal Article
  Year 2009 Publication Genetic Resources and Crop Evolution Abbreviated Journal Genet. Resour. Crop Evol.  
  Volume 56 Issue 3 Pages 405-419  
  Keywords AFLP; GM co-existence; Gene dispersal; Introgression; Risk assessment; SSAP  
  Abstract Spontaneous gene flow between wild and cultivated chicory, Cichorium intybus L., may have implications for the genetic structure and evolution of populations and varieties. One aspect of this crop-wild gene flow is the dispersal of transgenes from genetically modified varieties, e.g. gene flow from GM chicory to natural chicory could have unwanted consequences. With the purpose to identify and quantify crop-wild gene flow in chicory, we analysed introgression in 19 wild chicory populations and 16 accessions of chicory varieties and landraces distributed across Northern, Central and Mediterranean Europe. The analysis used 281 AFLP markers and 75 SSAP markers giving a total of 356 polymorphic markers. Results from model based assignments with the program STRUCTURE indicated many incidents of recent gene flow. Gene flow was observed both between cultivars and wild populations, between landraces and wild populations, between different wild populations as well as between cultivars. Population structure visualized by distance-based clustering showed a North-South geographical structuring of the wild populations, and a general grouping of the cultivars corresponding to known origin. The results indicated, however, that the structuring between the two groups of wild and cultivated types was weak. As crop and wild recipients are genetically close and genes are transferred between the two types rather frequently, focus on mitigating crop-wild gene flow should be increased, before transgenic varieties are cultivated openly.  
  Address [Kiaer, L. P.; Jorgensen, R. B.] DTU, Riso Natl Lab, Biosyst Dept, DK-4000 Roskilde, Denmark, Email: rikke.bagger.jorgensen@risoe.dk  
  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 (down) 0925-9864 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000264835300011 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 204  
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Author Almeras, T. openurl 
  Title Mechanical analysis of the strains generated by water tension in plant stems. Part II: strains in wood and bark and apparent compliance Type Journal Article
  Year 2008 Publication Tree Physiology Abbreviated Journal Tree Physiol.  
  Volume 28 Issue 10 Pages 1513-1523  
  Keywords biomechanics; calibration; diurnal strains; mechanical model; multilayer cylinder; water potential  
  Abstract Tree steins shrink in diameter during the day and swell during the night in response to changes in water tension in the xylem. Stein shrinkage can easily be measured in a nondestructive way, to derive continuous information about tree water status. The relationship between the strain and the change in water tension can be evaluated by empirical calibrations, or can be related to the structure of the plant. A mechanical analysis was performed to make this relationship explicit. The stem is modeled as a cylinder made of multiple layers of tissues, including heartwood, sapwood, and inner and outer bark. The effect of changes in water tension on the apparent strain at the surface of a tissue is quantified as a function of parameters defining stem anatomy and the mechanical properties of the tissues. Various possible applications in the context of tree physiology are suggested.  
  Address INRA UMR Ecofog, Kourou 97379, French Guiana, Email: t_almeras@hotmail.com  
  Corporate Author Thesis  
  Publisher HERON PUBLISHING Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (down) 0829-318X ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000260027200009 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 129  
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