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Author Clair, B.; Fournier, M.; Prevost, M.F.; Beauchene, J.; Bardet, S. openurl 
  Title Biomechanics of buttressed trees: Bending strains and stresses Type Journal Article
  Year 2003 Publication American Journal of Botany Abbreviated Journal Am. J. Bot.  
  Volume 90 Issue 9 Pages 1349-1356  
  Keywords biomechanics; buttress; Eleaocarpaceae; French Guiana; Sloanea spp.; tropical trees; wood  
  Abstract The different hypotheses about buttress function and formation mainly involve mechanical theory. Forces were applied to two trees of Sloanea spp.. a tropical genus that develops typical thin buttresses. and the three-dimensional strains were measured at different parts of the trunk base. Risks of failure were greater on the buttress sides, where shear and tangential stresses are greater, not on the ridges. in spite of high longitudinal (parallel to the grain) stresses. A simple beam model, computed from the second moment of area of digitized cross sections, is consistent with longitudinal strain variations but cannot predict accurately variations with height. Patterns of longitudinal strain variation along ridges are very different in the two individuals, owing to a pronounced lateral curvature in one specimen. The constant stress hypothesis is discussed based on these results. Without chronological data during the development of the tree. it cannot be proved that buttress formation is activated by stress or strain.  
  Address CIRAD ENGREF INRA, UMR Ecol Forets Guyane, F-97310 Kourou, Guyane Francais, France  
  Corporate Author Thesis  
  Publisher BOTANICAL SOC AMER INC Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) 0002-9122 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000185459000010 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 244  
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Author Lobova, T.A.; Mori, S.A.; Blanchard, F.; Peckham, H.; Charles-Dominique, P. openurl 
  Title Cecropia as a food resource for bats in French Guiana and the significance of fruit structure in seed dispersal and longevity Type Journal Article
  Year 2003 Publication American Journal of Botany Abbreviated Journal Am. J. Bot.  
  Volume 90 Issue 3 Pages 388-403  
  Keywords bat dispersal; Cecropia; French Guiana; fruit anatomy; fruit morphology; mucilage; Neotropical bats; soil seed bank  
  Abstract Cecropia (Cecropiaceae) is a Neotropical genus of pioneer plants. A review of bat/plant dispersal interactions revealed that 15 species of Cecropia are consumed by 32 species of bats. In French Guiana, bats were captured in primary and secondary forests, yielding 936 fecal samples with diaspores, among which 162 contained fruits of C. obtusa, C. palmata, and C. sciadophylla. A comparative morphological and anatomical study of fruits and seeds taken directly from herbarium specimens, bat feces, and an experimental soil seed bank was made. Contrary to previous reports, the dispersal unit of Cecropia is the fruit not the seed. Bats consume the infructescence, digest pulp derived from the enlarged, fleshy perianth, and defecate the fruits. The mucilaginous pericarp of Cecropia is described. The external mucilage production of Cecropia may facilitate endozoochory. The exocarp and part of the mesocarp may be lost after passage through the digestive tract of bats, but fruits buried for a year in the soil seed bank remain structurally unchanged. Fruit characters were found to be useful for identifying species of bat-dispersed Cecropia. Bat dispersal is not necessary for seed germination but it increases seed survival and subsequent germination. Fruit structure plays a significant role in seed longevity.  
  Address New York Bot Garden, Inst Systemat Bot, Bronx, NY 10458 USA  
  Corporate Author Thesis  
  Publisher BOTANICAL SOC AMER INC Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) 0002-9122 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000183133100008 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 272  
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Author Sarmiento, C.; Patino, S.; Paine, C.E.T.; Beauchene, J.; Thibaut, A.; Baraloto, C. openurl 
  Title Within-Individual Variation of Trunk and Branch Xylem Density in Tropical Trees Type Journal Article
  Year 2011 Publication American Journal of Botany Abbreviated Journal Am. J. Bot.  
  Volume 98 Issue 1 Pages 140-149  
  Keywords branch xylem density; French Guiana; functional trait; tropical trees; trunk xylem density; wood economics  
  Abstract Premise of the study : Wood density correlates with mechanical and physiological strategies of trees and is important for estimating global carbon stocks. Nonetheless, the relationship between branch and trunk xylem density has been poorly explored in neotropical trees. Here, we examine this relationship in trees from French Guiana and its variation among different families and sites, to improve the understanding of wood density in neotropical forests. Methods : Trunk and branch xylem densities were measured for 1909 trees in seven sites across French Guiana. A major-axis fit was performed to explore their general allometric relationship and its variation among different families and sites. Key results : Trunk xylem and branch xylem densities were significantly positively correlated, and their relationship explained 47% of the total variance. Trunk xylem was on average 9% denser than branch xylem. Family-level differences and interactions between family and site accounted for more than 40% of the total variance, whereas differences among sites explained little variation. Conclusions : Variation in xylem density within individual trees can be substantial, and the relationship between branch xylem and trunk xylem densities varies considerably among families and sites. As such, whole-tree biomass estimates based on non-destructive branch sampling should correct for both taxonomic and environmental factors. Furthermore, detailed estimates of the vertical distribution of wood density within individual trees are needed to determine the extent to which relying solely upon measures of trunk wood density may cause carbon stocks in tropical forests to be overestimated.  
  Address [Sarmiento, Carolina; Patino, Sandra; Baraloto, Christopher] INRA, UMR Ecol Forets Guyane, Kourou 97310, French Guiana, Email: carolinasar@gmail.com  
  Corporate Author Thesis  
  Publisher BOTANICAL SOC AMER INC Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) 0002-9122 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000285747900019 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 290  
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Author Coté, G.G.; Gibernau, M. url  openurl
  Title Distribution of calcium oxalate crystals in floral organs of araceae in relation to pollination strategy Type Journal Article
  Year 2012 Publication American Journal of Botany Abbreviated Journal Am. J. Bot.  
  Volume 99 Issue 7 Pages 1231-1242  
  Keywords Araceae; Beetles; Calcium oxalate; Crystal; Defense; Flowers; Herbivory; Pollination  
  Abstract Premise of the study: Many flowers are pollinated by potentially hungry insects, yet flowers also contain gametes and embryos which must be protected from predation. Microscopic calcium oxalate crystals in plant tissues have been proposed to protect against herbivory. Aroids, which have an unusual diversity of such crystals, also exhibit diverse pollination strategies. Many species have pollinators that do not feed while visiting the flowers, while other species, especially those pollinated by beetles, offer sterile staminodia as food rewards. We examined flowers of 21 aroid species with various pollination strategies to test the hypothesis that crystals protect vital gametes and embryos while allowing consumption of food bribes.Methods: Aroid inflorescences collected from the field or from greenhouse material were sectioned, cleared, and examined by bright field and polarization microscopy.Key results: All species examined, regardless of pollination strategy, arrayed crystals around unshed pollen and ovules. Less vital tissues, such as odoriferous appendages, had few crystals. Staminodia offered as food to beetle pollinators, however, differed greatly between species in their crystal contents. Some had minimal crystals; some had crystals in patterns suggesting they limit beetle feeding; still others had abundant crystals in no obvious pattern.Conclusions: The results are consistent with crystals protecting against insect predation of gametes and embryos. However, the role of crystals in food-bribe staminodia is unclear. They may limit and direct feeding by beetles in some species, while in others they might have no protective role. © 2012 Botanical Society of America.  
  Address CNRS-Ecolog (UMR 8172), Campus Agronomique BP316, Korou cedex 97379, 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 (up) 00029122 (Issn) ISBN Medium  
  Area Expedition Conference  
  Notes Export Date: 10 August 2012; Source: Scopus; Coden: Ajboa; doi: 10.3732/ajb.1100499; Language of Original Document: English; Correspondence Address: Coté, G. G.; Biology Department, Radford University, Radford, VA 24142-6931, United States; email: gcote@radford.edu Approved no  
  Call Number EcoFoG @ webmaster @ Serial 420  
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Author Fu, T.; Touboul, D.; Della-Negra, S.; Houel, E.; Amusant, N.; Duplais, C.; Fisher, G.L.; Brunelle, A. url  doi
openurl 
  Title Tandem Mass Spectrometry Imaging and in Situ Characterization of Bioactive Wood Metabolites in Amazonian Tree Species Sextonia rubra Type Journal Article
  Year 2018 Publication Analytical Chemistry Abbreviated Journal Anal. Chem.  
  Volume 90 Issue 12 Pages 7535-7543  
  Keywords  
  Abstract Driven by a necessity for confident molecular identification at high spatial resolution, a new time-of-flight secondary ion mass spectrometry (TOF-SIMS) tandem mass spectrometry (tandem MS) imaging instrument has been recently developed. In this paper, the superior MS/MS spectrometry and imaging capability of this new tool is shown for natural product study. For the first time, via in situ analysis of the bioactive metabolites rubrynolide and rubrenolide in Amazonian tree species Sextonia rubra (Lauraceae), we were able both to analyze and to image by tandem MS the molecular products of natural biosynthesis. Despite the low abundance of the metabolites in the wood sample(s), efficient MS/MS analysis of these γ-lactone compounds was achieved, providing high confidence in the identification and localization. In addition, tandem MS imaging minimized the mass interferences and revealed specific localization of these metabolites primarily in the ray parenchyma cells but also in certain oil cells and, further, revealed the presence of previously unidentified γ-lactone, paving the way for future studies in biosynthesis.  
  Address  
  Corporate Author Thesis  
  Publisher American Chemical Society Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) 0003-2700 ISBN Medium  
  Area Expedition Conference  
  Notes doi: 10.1021/acs.analchem.8b01157 Approved no  
  Call Number EcoFoG @ webmaster @ Serial 834  
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Author Seipke, R.F.; Barke, J.; Ruiz-Gonzalez, M.X.; Orivel, J.; Yu, D.W.; Hutchings, M.I. url  openurl
  Title Fungus-growing Allomerus ants are associated with antibiotic-producing actinobacteria Type Journal Article
  Year 2012 Publication Antonie van Leeuwenhoek, International Journal of General and Molecular Microbiology Abbreviated Journal Antonie Van Leeuwenhoek Int. J. Gen. Mol. Microbiol.  
  Volume 101 Issue 2 Pages 443-447  
  Keywords Allomerus ants; Amycolatopsis; Ant-bacteria symbioses; Fungus-growing ants; Insect fungiculture; Streptomyces  
  Abstract Fungus-growing attine ants use natural-product antibiotics produced by mutualist actinobacteria as 'weedkillers' in their fungal gardens. Here we report for the first time that fungus-growing Allomerus ants, which lie outside the tribe Attini, are associated with antifungal-producing actinobacteria, which offer them protection against non-cultivar fungi isolated from their ant-plants. © 2011 Springer Science+Business Media B.V.  
  Address State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, Yunnan 650223, China  
  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 (up) 00036072 (Issn) ISBN Medium  
  Area Expedition Conference  
  Notes Export Date: 21 March 2012; Source: Scopus; Coden: Aljma; doi: 10.1007/s10482-011-9621-y; Language of Original Document: English; Correspondence Address: Hutchings, M.I.; School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich NR4 7TJ, United Kingdom; email: m.hutchings@uea.ac.uk Approved no  
  Call Number EcoFoG @ webmaster @ Serial 385  
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Author Groc, S.; Delabie, J.H.C.; Longino, J.T.; Orivel, J.; Majer, J.D.; Vasconcelos, H.L.; Dejean, A. openurl 
  Title A new method based on taxonomic sufficiency to simplify studies on Neotropical ant assemblages Type Journal Article
  Year 2010 Publication Biological Conservation Abbreviated Journal Biol. Conserv.  
  Volume 143 Issue 11 Pages 2832-2839  
  Keywords Higher-taxon surrogacy; “Indicator taxa” surrogacy; Multi-taxonomic assemblages; Mixed-level method; Terrestrial arthropod assemblages; Biodiversity indicators  
  Abstract Insects, particularly ants, are good bioindicators of the state of ecosystems. Nevertheless, incorporating them into conservation surveys is expensive due to problems associated with their identification, which is exacerbated by the fact that there are fewer and fewer taxonomists working today. “Taxonomic sufficiency” (TS), which identifies organisms to a level of taxonomic resolution sufficient enough to satisfy the objectives of a study, has never been applied to Neotropical ant communities. We analysed five Neotropical datasets representing ant assemblages collected with different sampling methods in various habitats. We first treated them using two complementary and cumulative TS methods, higher-taxon and “indicator taxa” surrogacies, before testing a new approach called “mixed-level method” that combines the two previous approaches. For the higher-taxon surrogacy, we showed that, above species, genus is the most informative taxonomic level. Then, mixed-level method provided more information on ant assemblages than did the two others, even though the “indicator taxa” surrogacy was based on relevant indicator genera. Although habitat type has no effect on its efficiency, this new method is influenced by the dataset structure and the type of sampling method used to collect data. We have thus developed a new method for analyzing Neotropical ant faunas that enables the taxonomic work linked to the identification of problematic species to be significantly reduced, while conserving most of the information on the ant assemblage. This method should enhance the work of Neotropical entomologists not specialised in taxonomy, particularly those concerned with biological conservation and indication. (C) 2010 Elsevier Ltd. All rights reserved.  
  Address [Groc, Sarah; Dejean, Alain] CNRS, Ecol Forets Guyane UMR 8172, F-97379 Kourou, France, Email: sarah.groc@laposte.net  
  Corporate Author Thesis  
  Publisher ELSEVIER SCI LTD Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) 0006-3207 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000283412300048 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 22  
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Author Degen, B.; Blanc, L.; Caron, H.; Maggia, L.; Kremer, A.; Gourlet-Fleury, S. openurl 
  Title Impact of selective logging on genetic composition and demographic structure of four tropical tree species Type Journal Article
  Year 2006 Publication Biological Conservation Abbreviated Journal Biol. Conserv.  
  Volume 131 Issue 3 Pages 386-401  
  Keywords demography; genetic diversity; logging; phenology; pollen and seed dispersal; simulation; trees; tropics  
  Abstract Over-exploitation and fragmentation are serious problems for tropical forests. Most sustainable forest management practices avoid clear-cuts and apply selective logging systems focused on a few commercial species. We applied a simulation model to estimate the impact of such selective logging scenarios on the genetic diversity and demography of four tropical tree species from French Guiana. The simulations used data on genetic and demographic composition, growth, phenology and pollen and seed dispersal obtained for Dicorynia guianensis, Sextonia rubra, Symphonia globulifera and Vouacapoua americana at the experimental site in Paracou. Whereas Symphonia globulifera serves as a model for a species with low logging pressure, the other three species represent the most exploited tree species in French Guiana. In simulations with moderate logging, typical for French Guiana, with large cutting diameter (> 60 cm diameter) and long cutting cycles (65 years), the two species V. americana and Sextonia rubra were not able to recover their initial stock at the end of the rotation period, with a large decrease in the number of individuals and in basal area. Under a more intensive logging system (cutting diameter > 45 cm diameter, cutting cycles of 30 years) that is common practice in the Brazilian Amazon, only Symphonia globulifera showed no negative impact. Generally, the differences between the genetic parameters in the control scenarios without logging and the logging scenarios were surprisingly small. The main reasons for this were the overlapping of generations and the effective dispersal ability of gene vectors in all species, which guarantee relative homogeneity of the genetic structure in different age classes. Nevertheless, decreasing the population size by logging reduced the number of genotypes and caused higher genetic distances between the original population and the population at the end of the logging cycles. Sensitivity analysis showed that genetic changes in the logging scenarios were principally determined by the growth, densities and cutting diameter of each species, and only to a very small extent by the reproductive system including factors such as pollen and seed dispersal and flowering phenology. (c) 2006 Elsevier Ltd. All rights reserved.  
  Address BFH, Inst Forstgenet & Forstpflanzenzuchtung, D-22927 Grosshansdorf, Germany, Email: b.degen@holz.uni-hamburg.de  
  Corporate Author Thesis  
  Publisher ELSEVIER SCI LTD Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) 0006-3207 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000239139400004 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 180  
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Author Clair, B.; Almeras, T.; Yamamoto, H.; Okuyama, T.; Sugiyama, J. openurl 
  Title Mechanical behavior of cellulose microfibrils in tension wood, in relation with maturation stress generation Type Journal Article
  Year 2006 Publication Biophysical Journal Abbreviated Journal Biophys. J.  
  Volume 91 Issue 3 Pages 1128-1135  
  Keywords  
  Abstract A change in cellulose lattice spacing can be detected during the release of wood maturation stress by synchrotron x-ray diffraction experiment. The lattice strain was found to be the same order of magnitude as the macroscopic strain. The fiber repeat distance, 1.033 nm evaluated for tension wood after the release of maturation stress was equal to the conventional wood values, whereas the value before stress release was larger, corresponding to a fiber repeat of 1.035 nm, nearly equal to that of cotton and ramie. Interestingly, the fiber repeat varied from 1.033 nm for wood to 1.040 nm for algal cellulose, with an increasing order of lateral size of cellulose microfibrils so far reported. These lines of experiments demonstrate that, before the stress release, the cellulose was in a state of tension, which is, to our knowledge, the first experimental evidence supporting the assumption that tension is induced in cellulose microfibrils.  
  Address Kyoto Univ, Res Inst Sustainable Humanosphere, Uji, Kyoto, Japan, Email: sugiyama@rish.kyoto-u.ac.jp  
  Corporate Author Thesis  
  Publisher BIOPHYSICAL SOCIETY Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) 0006-3495 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000239086800039 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 224  
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Author Wagner, F.; Rutishauser, E.; Blanc, L.; Herault, B. openurl 
  Title Effects of Plot Size and Census Interval on Descriptors of Forest Structure and Dynamics Type Journal Article
  Year 2010 Publication Biotropica Abbreviated Journal Biotropica  
  Volume 42 Issue 6 Pages 664-671  
  Keywords Amazonia; biomass fluxes; coefficient of variation; forest permanent plots; turnover rates; WinBUGS  
  Abstract This study was designed to explicitly formulate the effect of census interval and plot size on the variability of descriptors of tropical forest structure (stand density, basal area, aboveground biomass [AGB]) and dynamic (tree growth, mortality and recruitment rates, biomass fluxes). A unique dataset from a broad plot network (37.5 ha) surveyed every 2 yr over a 16-yr period was used to develop and parameterize a new statistical model predicting the coefficients of variation for each forest descriptor. More than 90 percent of the inherent variability of these coefficients was predicted using a simple model including plot size and census interval in a Bayesian modeling framework. All descriptors of forest structure varied by <10 percent for plot sizes 42 ha. Among the descriptors of forest dynamics, AGB loss was the most variable. The number of 6.25 ha plots required to estimate its mean, over a 16-yr period, within a 20 percent error of the mean remains above four. This contrasts with a relative constant flux of biomass entering the plot through tree growth and tree recruitment. Tree growth was remarkably well estimated with <15 percent variability for a 2-yr census in a plot of 2 ha. This study provides an easy method to assess dataset limitations in efforts to estimate descriptors of forest structure and dynamic, which is of primary importance to decipher any clear consequences of global change in tropical forests.  
  Address [Wagner, Fabien; Herault, Bruno] Univ Antilles Guyane, UMR Ecol Forets Guyane, Kourou 97379, French Guiana, Email: bruno.herault@ecofog.gf  
  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 (up) 0006-3606 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000283949700006 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 16  
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