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Author Almeras, T.; Yoshida, M.; Okuyama, T. openurl 
  Title Strains inside xylem and inner bark of a stem submitted to a change in hydrostatic pressure Type Journal Article
  Year 2006 Publication Trees-Structure and Function Abbreviated Journal Trees-Struct. Funct.  
  Volume 20 Issue 4 Pages 460-467  
  Keywords diurnal strains; hydrostatic pressure; xylem; inner bark; mechanical properties  
  Abstract (down) Tangential strains were measured with strain gauges at the surface of xylem and inner bark of saplings of Cryptomeria japonica D. Don. and Fagus silvatica L. during a pressurization test. The test consists in submitting the whole sapling to an artificially imposed hydrostatic pressure of increasing magnitude. The elastic response of the stems was found linear both at the surface of xylem and inner bark. A simple geometric model allows to compute radial strains in each tissue from tangential strain data. Inside inner bark, radial strains are much larger than tangential strains, because tangential strains are restrained by the core of wood. The material compliance of each tissue was computed as the ratio between the radial strain and the pressure that caused it. The material compliance of xylem is much lower than that of inner bark, but, as its thickness is much larger, its contribution to the apparent behavior of the stem is not negligible. Computation of material compliances by this pressurization test provides information about the specific behavior of each tissue in response to hydrostatic pressure. This can be used to estimate and interpret the calibration factor linking the water status of the plant to the apparent strain measured at its surface.  
  Address Nagoya Univ, Grad Sch Bioagr Sci, Lab Biomat Phys, Chikusa Ku, 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 0931-1890 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000237858100007 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 225  
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Author Dejean, A.; Petitclerc, F.; Azémar, F. doi  openurl
  Title Seasonality influences ant-mediated nutrient acquisition (myrmecotrophy) by a Neotropical myrmecophyte Type Journal Article
  Year 2020 Publication Evolutionary Ecology Abbreviated Journal Evol. Ecol.  
  Volume 34 Issue 4 Pages 645-657  
  Keywords Ant-plant relationships; Mutualism; Myrmecophyte; Myrmecotrophy; Phenology; Stable isotopes; ant; herb; host plant; life cycle; myrmecochory; myrmecophyte; Neotropical Region; phenology; seasonality; stable isotope; understory; Gentianaceae; Tachia; Tachia guianensis  
  Abstract (down) Tachia guianensis (Gentianaceae), a Neotropical understory myrmecophyte, shelters ant colonies in its hollow trunks and branches (domatia). In turn, it is protected from defoliators and obtains nutrients from ant-produced wastes (myrmecotrophy). Aiming to verify if seasonality influences nitrogen assimilation via ant wastes using the stable isotope nitrogen-15, we first studied Tachia’s phenology and its seasonal leaf production, and then the life cycle of its two more frequent guest ant species. We found that leaf production was much higher during the rainy than the dry season. Mature guest ant colonies produced sexuals regardless of the season and the net weight of the waste piles inside the domatia did not vary between seasons, so that the availability of nutrients to their host plant is steady year-long. By providing the two most frequent mutualistic guest ant species with food enriched with nitrogen-15, we showed that Tachia individuals assimilate more nitrogen from ant wastes during the rainy season, when the plant is physiologically active, compared to the dry season. Thus, one can deduce that the increase in nitrogen assimilation during the rainy season is determined by the increase in Tachia’s physiological activity during that season. Information gathered through a bibliographic compilation confirms that none of the 15 ant species known to be associated with myrmecophytes for which the life cycle was studied is characterized by seasonal reproduction (which would result in fluctuating waste production). The same is true for 49.7% of 167 tropical ant species (seasonal production for the remaining species). We concluded that, in contrast to the non-seasonal ant colony reproductive cycle, Tachia’s phenology determines the myrmecotrophic assimilation rate. © 2020, Springer Nature Switzerland AG.  
  Address CNRS, UMR EcoFoG, AgroParisTech, CIRAD, INRAE, Université des Antilles, Université de Guyane, Kourou, 97310, France  
  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 02697653 (Issn) ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number EcoFoG @ webmaster @ Serial 956  
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Author Maia, A.C.D.; Gibernau, M.; Carvalho, A.T.; Gonçalves, E.G.; Schlindwein, C. url  openurl
  Title The cowl does not make the monk: Scarab beetle pollination of the Neotropical aroid Taccarum ulei (Araceae: Spathicarpeae) Type Journal Article
  Year 2013 Publication Biological Journal of the Linnean Society Abbreviated Journal  
  Volume 108 Issue 1 Pages 22-34  
  Keywords Flower predation; Nocturnal pollinators; Pollination syndromes; Scarabaeidae; Thermogenesis  
  Abstract (down) Taccarum ulei (Araceae, Spathicarpeae) is a seasonal geophytic aroid, native to north-eastern Brazil, that flowers during two months of the rainy season. Patterns of floral thermogenesis, pollination biology, and floral traits associated with pollination syndromes were studied and compared with those of other Araceae. Two species of cyclocephaline scarabs (Scarabaeidae, Cyclocephalini) were recognized as effective pollinators: Cyclocephala celata and Cyclocephala cearae. Larvae of an unidentified species of fruit fly (Melanolomaspp., Richardiidae, Diptera) were also frequently observed in inflorescences at various maturation stages, feeding on the connectives of male florets and fruits, and thus lowering the reproductive success of individual plants. Beetles were attracted by odoriferous inflorescences in the early evening of the first day of anthesis, during the female phase. The emission of attractive volatiles was coupled with intense thermogenic activity in the entire spadix, unlike other aroids in which only certain zones of the spadix heat up. Pollen release, which marks the beginning of the male phase on the subsequent evening, was not related to floral thermogenesis. Comparative multivariate analysis of the floral traits of T.ulei points to a beetle-pollinated aroid, although some of the observed traits of the species are not common to other taxa sharing this pollination strategy. Such incongruence might be explained by the evolutionary history of the tribe Spathicarpeae and potential pollinator shifts. © 2012 The Linnean Society of London.  
  Address Departamento de Botânica, Universidade Federal de Minas Gerais, Belo Horizonte, 31270-901, Brazil  
  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 ISBN Medium  
  Area Expedition Conference  
  Notes Export Date: 3 January 2013; Source: Scopus Approved no  
  Call Number EcoFoG @ webmaster @ Serial 453  
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Author Dejean, A.; Corbara, B.; Céréghino, R.; Leponce, M.; Roux, O.; Rossi, V.; Delabie, J.H.C.; Compin, A. doi  openurl
  Title Traits allowing some ant species to nest syntopically with the fire ant Solenopsis saevissima in its native range Type Journal Article
  Year 2015 Publication Insect Science Abbreviated Journal Insect Science  
  Volume 22 Issue 2 Pages 289-294  
  Keywords Ant community; Fire ants; Invasive species; Solenopsis saevissima; Species coexistence; Supercoloniality  
  Abstract (down) Supercolonies of the red fire ant Solenopsis saevissima (Smith) develop in disturbed environments and likely alter the ant community in the native range of the species. For example, in French Guiana only 8 ant species were repeatedly noted as nesting in close vicinity to its mounds. Here, we verified if a shared set of biological, ecological, and behavioral traits might explain how these 8 species are able to nest in the presence of S. saevissima. We did not find this to be the case. We did find, however, that all of them are able to live in disturbed habitats. It is likely that over the course of evolution each of these species acquired the capacity to live syntopically with S. saevissima through its own set of traits, where colony size (4 species develop large colonies), cuticular compounds which do not trigger aggressiveness (6 species) and submissive behaviors (4 species) complement each other. © 2013 Institute of Zoology, Chinese Academy of Sciences.  
  Address U.P.A. Laboratório de Mirmecologia, Convênio UESC/CEPLAC, C.P. 7Itabuna, Bahia, Brazil  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
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  ISSN ISBN Medium  
  Area Expedition Conference  
  Notes Export Date: 9 April 2015 Approved no  
  Call Number EcoFoG @ webmaster @ Serial 594  
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Author Rutishauser, E.; Herault, B.; Baraloto, C.; Blanc, L.; Descroix, L.; Sotta, E.D.; Ferreira, J.; Kanashiro, M.; Mazzei, L.; D'Oliveira, M.V.N.; De Oliveira, L.C.; Peña-Claros, M.; Putz, F.E.; Ruschel, A.R.; Rodney, K.; Roopsind, A.; Shenkin, A.; Da Silva, K.E.; De Souza, C.R.; Toledo, M.; Vidal, E.; West, T.A.P.; Wortel, V.; Sist, P. url  openurl
  Title Rapid tree carbon stock recovery in managed Amazonian forests Type Journal Article
  Year 2015 Publication Current Biology Abbreviated Journal Current Biology  
  Volume 25 Issue 18 Pages R787-R788  
  Keywords  
  Abstract (down) Summary While around 20% of the Amazonian forest has been cleared for pastures and agriculture, one fourth of the remaining forest is dedicated to wood production [1]. Most of these production forests have been or will be selectively harvested for commercial timber, but recent studies show that even soon after logging, harvested stands retain much of their tree-biomass carbon and biodiversity [2,3]. Comparing species richness of various animal taxa among logged and unlogged forests across the tropics, Burivalova et al.[4] found that despite some variability among taxa, biodiversity loss was generally explained by logging intensity (the number of trees extracted). Here, we use a network of 79 permanent sample plots (376 ha total) located at 10 sites across the Amazon Basin [5] to assess the main drivers of time-to-recovery of post-logging tree carbon (Table S1). Recovery time is of direct relevance to policies governing management practices (i.e., allowable volumes cut and cutting cycle lengths), and indirectly to forest-based climate change mitigation interventions. © 2015 Elsevier Ltd.  
  Address Biodiversity Department, CELOS, Paramaribo, Paramaribo, Suriname  
  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 ISBN Medium  
  Area Expedition Conference  
  Notes Export Date: 2 October 2015 Approved no  
  Call Number EcoFoG @ webmaster @ Serial 626  
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Author Clair, B.; Ghislain, B.; Prunier, J.; Lehnebach, R.; Beauchene, J.; Alméras, T. pdf  url
doi  openurl
  Title Mechanical contribution of secondary phloem to postural control in trees: the bark side of the force Type Journal Article
  Year 2019 Publication New Phytologist Abbreviated Journal New Phytol  
  Volume 221 Issue 1 Pages 209-217  
  Keywords bark; Malvaceae; maturation stress; secondary phloem; tree biomechanics  
  Abstract (down) Summary To grow straight, plants need a motor system that controls posture by generating forces to offset gravity. This motor function in trees was long thought to be only controlled by internal forces induced in wood. Here we provide evidence that bark is involved in the generation of mechanical stresses in several tree species. Saplings of nine tropical species were grown tilted and staked in a shadehouse and the change in curvature of the stem was measured after releasing from the pole and after removing the bark. This first experiment evidenced the contribution of bark in the up-righting movement of tree stems. Combined mechanical measurements of released strains on adult trees and microstructural observations in both transverse and longitudinal/tangential plane enabled us to identify the mechanism responsible for the development of asymmetric mechanical stress in the bark of stems of these species. This mechanism does not result from cell wall maturation like in wood, or from the direct action of turgor pressure like in unlignified organs, but is the consequence of the interaction between wood radial pressure and a smartly organized trellis structure in the inner bark.  
  Address  
  Corporate Author Thesis  
  Publisher John Wiley & Sons, Ltd (10.1111) Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0028-646x ISBN Medium  
  Area Expedition Conference  
  Notes doi: 10.1111/nph.15375 Approved no  
  Call Number EcoFoG @ webmaster @ Serial 853  
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Author Svensk, M.; Coste, S.; Gérard, B.; Gril, E.; Julien, F.; Maillard, P.; Stahl, C.; Leroy, C. doi  openurl
  Title Drought effects on resource partition and conservation among leaf ontogenetic stages in epiphytic tank bromeliads Type Journal Article
  Year 2020 Publication Physiologia Plantarum Abbreviated Journal Physiol. Plant.  
  Volume 170 Issue 4 Pages 488-507  
  Keywords chlorophyll; nitrogen; water; Bromeliaceae; drought; metabolism; photosynthesis; plant leaf; Bromeliaceae; Chlorophyll; Droughts; Nitrogen; Photosynthesis; Plant Leaves; Water  
  Abstract (down) Studying the response to drought stress of keystone epiphytes such as tank bromeliads is essential to better understand their resistance capacity to future climate change. The objective was to test whether there is any variation in the carbon, water and nutrient status among different leaf ontogenetic stages in a bromeliad rosette subjected to a gradient of drought stress. We used a semi-controlled experiment consisting in a gradient of water shortage in Aechmea aquilega and Lutheria splendens. For each bromeliad and drought treatment, three leaves were collected based on their position in the rosette and several functional traits related to water and nutrient status, and carbon metabolism were measured. We found that water status traits (relative water content, leaf succulence, osmotic and midday water potentials) and carbon metabolism traits (carbon assimilation, maximum quantum yield of photosystem II, chlorophyll and starch contents) decreased with increasing drought stress, while leaf soluble sugars and carbon, nitrogen and phosphorus contents remained unchanged. The different leaf ontogenetic stages showed only marginal variations when subjected to a gradient of drought. Resources were not reallocated between different leaf ontogenetic stages but we found a reallocation of soluble sugars from leaf starch reserves to the root system. Both species were capable of metabolic and physiological adjustments in response to drought. Overall, this study advances our understanding of the resistance of bromeliads faced with increasing drought stress and paves the way for in-depth reflection on their strategies to cope with water shortage. © 2020 Scandinavian Plant Physiology Society  
  Address Laboratoire Ecologie Fonctionnelle et Environnement, Université de Toulouse, CNRS, Toulouse, 31062, France  
  Corporate Author Thesis  
  Publisher Blackwell Publishing Ltd Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 00319317 (Issn) ISBN Medium  
  Area Expedition Conference  
  Notes PDF trop gros voir la documentaliste – merci Approved no  
  Call Number EcoFoG @ webmaster @ Serial 943  
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Author Almeras, T.; Fournier, M. openurl 
  Title Biomechanical design and long-term stability of trees: Morphological and wood traits involved in the balance between weight increase and the gravitropic reaction Type Journal Article
  Year 2009 Publication Journal of Theoretical Biology Abbreviated Journal J. Theor. Biol.  
  Volume 256 Issue 3 Pages 370-381  
  Keywords Mechanical design; Gravitropism; Bending stresses; Allometry; Reaction wood  
  Abstract (down) Studies on tree biomechanical design usually focus on stem stiffness, resistance to breakage or uprooting, and elastic stability. Here we consider another biomechanical constraint related to the interaction between growth and gravity. Because stems are slender structures and are never perfectly symmetric, the increase in tree mass always causes bending movements. Given the current mechanical design of trees, integration of these movements over time would ultimately lead to a weeping habit unless some gravitropic correction occurs. This correction is achieved by asymmetric internal forces induced during the maturation of new wood. The long-term stability of a growing stem therefore depends on how the gravitropic correction that is generated by diameter growth balances the disturbance due to increasing self weight. General mechanical formulations based on beam theory are proposed to model these phenomena. The rates of disturbance and correction associated with a growth increment are deduced and expressed as a function of elementary traits of stem morphology, cross-section anatomy and wood properties. Evaluation of these traits using previously published data shows that the balance between the correction and the disturbance strongly depends on the efficiency of the gravitropic correction, which depends on the asymmetry of wood maturation strain, eccentric growth, and gradients in wood stiffness. By combining disturbance and correction rates, the gravitropic performance indicates the dynamics of stem bending during growth. It depends on stem biomechanical traits and dimensions. By analyzing dimensional effects, we show that the necessity for gravitropic correction might constrain stem allometric growth in the long-term. This constraint is compared to the requirement for elastic stability, showing that gravitropic performance limits the increase in height of tilted stem and branches. The performance of this function may thus limit the slenderness and lean of stems, and therefore the ability of the tree to capture light in a heterogeneous environment. (c) 2008 Elsevier Ltd. All rights reserved.  
  Address [Almeras, T.; Fournier, M.] INRA, UMR Ecol Forets Guyane, F-97310 Kourou, France, Email: t_almeras@hotmail.com  
  Corporate Author Thesis  
  Publisher ACADEMIC PRESS LTD 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 0022-5193 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000263077100008 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 123  
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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 Water Abbreviated Journal Water  
  Volume 7 Issue 8 Pages 4108-4128  
  Keywords 18O/2H stable isotope; Hydrology; Mangrove; Salinity; Swamp forest; Water level  
  Abstract (down) 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  
  Publisher Place of Publication Editor  
  Language Summary Language Original Title  
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  Area Expedition Conference  
  Notes Export Date: 8 September 2015 Approved no  
  Call Number EcoFoG @ webmaster @ Serial 621  
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Author González, A.L.; Céréghino, R.; Dézerald, O.; Farjalla, V.F.; Leroy, C.; Richardson, B.A.; Richardson, M.J.; Romero, G.Q.; Srivastava, D.S. url  doi
openurl 
  Title Ecological mechanisms and phylogeny shape invertebrate stoichiometry: A test using detritus-based communities across Central and South America Type Journal Article
  Year 2018 Publication Functional Ecology Abbreviated Journal Funct Ecol  
  Volume 32 Issue 10 Pages 2448-2463  
  Keywords body size scaling; carnivores; detritivores; ecological stoichiometry; macroinvertebrates; nitrogen; phosphorous; phylogenetic signal  
  Abstract (down) Stoichiometric differences among organisms can affect trophic interactions and rates of nutrient cycling within ecosystems. However, we still know little about either the underlying causes of these stoichiometric differences or the consistency of these differences across large geographical extents. Here, we analyse elemental (carbon, nitrogen, phosphorus) composition of 872 aquatic macroinvertebrates (71 species) inhabiting tank bromeliads (n = 140) from five distantly located sites across Central and South America to (i) test phylogenetic, trophic and body size scaling explanations for why organisms differ in elemental composition and (ii) determine whether patterns in elemental composition are universal or context dependent. Taxonomy explained most variance in elemental composition, even though phylogenetic signals were weak and limited to regional spatial extents and to the family level. The highest elemental contents and lowest carbon:nutrient ratios were found in organisms at high trophic levels and with smaller body size, regardless of geographical location. Carnivores may have higher nutrient content and lower carbon:nutrient ratios than their prey, as organisms optimize growth by choosing the most nutrient-rich resources to consume and then preferentially retain nutrients over carbon in their bodies. Smaller organisms grow proportionally faster than large organisms and so are predicted to have higher nutrient requirements to fuel RNA and protein synthesis. Geography influenced the magnitude, more than the direction, of the ecological and/or phylogenetic effects on elemental composition. Overall, our results show that both ecological (i.e. trophic group) and evolutionary drivers explain among-taxa variation in the elemental content of invertebrates, whereas intraspecific variation is mainly a function of body size. Our findings also demonstrate that restricting analyses of macroinvertebrate stoichiometry solely to either the local scale or species level affects inferences of the patterns in invertebrate elemental content and their underlying mechanisms.  
  Address  
  Corporate Author Thesis  
  Publisher John Wiley & Sons, Ltd (10.1111) Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0269-8463 ISBN Medium  
  Area Expedition Conference  
  Notes doi: 10.1111/1365-2435.13197 Approved no  
  Call Number EcoFoG @ webmaster @ Serial 849  
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