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Author Stahl, C.; Burban, B.; Goret, J.Y.; Bonal, D. openurl 
  Title Seasonal variations in stem CO(2) efflux in the Neotropical rainforest of French Guiana Type Journal Article
  Year 2011 Publication Annals of Forest Science Abbreviated Journal Ann. For. Sci.  
  Volume 68 Issue 4 Pages 771-782  
  Keywords (down) Tropical rainforest; Stem CO(2) efflux; Soil water content; Terra Firme forest; Seasonally flooded forest  
  Abstract Introduction Stem CO(2) efflux (E (s)) is a significant component of total ecosystem respiration, but there is only scant information on seasonal variations in E (s) in tropical rainforests and on the main factors explaining these variations. Methods We conducted a comprehensive 18-month study in French Guiana to try to better understand which environmental factors contribute to seasonal variations in E (s) in two habitats differing in soil water conditions. Results In both habitats, large seasonal variations in E (s) were observed for most trees. The main variations occurred during climatic transition periods and were consistent with seasonal variations in soil and total ecosystem respiration. Discussion Seasonal variations in atmospheric conditions, including air temperature, did not explain seasonal variations in E (s). In contrast, seasonal variations in surface soil water content clearly induced seasonal variations in E (s) in each habitat. Both soil drought and flooded conditions induced a decrease in E (s). Conclusion Our results emphasize the need to integrate the influence of soil water content on E (s) into global models that simulate the response of forest ecosystem fluxes to climate changes.  
  Address [Bonal, D] INRA, UMR INRA UHP Ecol & Ecophysiol Forestiere 1137, F-54280 Champenoux, France, Email: bonal@nancy.inra.fr  
  Corporate Author Thesis  
  Publisher Springer France Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1286-4560 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000292553400011 Approved no  
  Call Number EcoFoG @ webmaster @ Serial 327  
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Author Aguilos, M.; Hérault, B.; Burban, B.; Wagner, F.; Bonal, D. url  doi
openurl 
  Title What drives long-term variations in carbon flux and balance in a tropical rainforest in French Guiana? Type Journal Article
  Year 2018 Publication Agricultural and Forest Meteorology Abbreviated Journal  
  Volume 253–254 Issue Pages 114-123  
  Keywords (down) Tropical rainforest; Nee; Gpp; Ecosystem respiration; Radiation; Drought  
  Abstract A thorough understanding of how tropical forests respond to climate is important to improve ecosystem process models and to reduce uncertainties in current and future global carbon balance calculations. The Amazon rainforest, a major contributor to the global carbon cycle, is subject to strong intra- and interannual variations in climate conditions. Understanding their effect on carbon fluxes between the ecosystem and the atmosphere and on the resulting carbon balance is still incomplete. We examined the long-term (over a 12-year period; 2004–2015) variations in gross primary productivity (GPP), ecosystem respiration (RE) and net ecosystem exchange (NEE) in a tropical rainforest in French Guiana and identified key climatic drivers influencing the changes. The study period was characterized by strong differences in climatic conditions among years, particularly differences in the intensity of the dry and wet seasons, as well as differences in annual carbon fluxes and balance. Annual average GPP varied from 3384.9?g?C?m-2?yr?1 (95% CI [3320.7, 3445.9]) to 4061.2?g?C?m-2?yr?1 (95% CI [3980.1, 4145.0]). RE varied even more than GPP, with a difference of 933.1?C?m-2?yr?1 between the minimum (3020.6?g?C?m-2?yr?1; 95% CI [2889.4, 3051.3]) and maximum (3953.7?g?C?m-2?yr?1; 95% CI [3887.6, 4019.6]) values. Although NEE showed large interannual variability (nine-fold), from ?65.6?g?C?m-2?yr?1 (95% CI [?4.4, ?126.0]) to ?590.5?g?C?m-2 yr?1 (95% CI [?532.3, ?651.6]), the forest remained a carbon sink over the 12-year period. A combination of global radiation (Rg), relative extractable water (REW) and soil temperature (Ts) explained 51% of the daily variations for GPP, 30% for RE and 39% for NEE. Global radiation was always the best predictor of these variations, but soil water content and temperature did also influence carbon fluxes and balance. Seasonally, Rg was the major controlling factor for GPP, RE and NEE during the wet season. During the dry season, variations in carbon fluxes and balance were poorly explained by climate factors. Yet, REW was the key driver of variations in NEE during the dry season. This study highlights that, over the long-term, carbon fluxes and balance in such tropical rainforest ecosystems are largely controlled by both radiation and water limitation. Even though variations in Rg have a greater impact on these fluxes, water limitation during seasonal droughts is enough to reduce ecosystem productivity, respiration and carbon uptake. The reduced precipitation expected in tropical rainforest areas under future climatic conditions will therefore strongly influence carbon fluxes and carbon uptake. This study also highlights the importance for land surface or dynamic global vegetation models to consider the main drivers of carbon fluxes and balance separately for dry and wet seasons.  
  Address  
  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 0168-1923 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number EcoFoG @ webmaster @ Serial 792  
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Author Phillips, P.D.; Thompson, I.S.; Silva, J.N.M.; van Gardingen, P.R.; Degen, B. openurl 
  Title Scaling up models of tree competition for tropical forest population genetics simulation Type Journal Article
  Year 2004 Publication Ecological Modelling Abbreviated Journal Ecol. Model.  
  Volume 180 Issue 2-3 Pages 419-434  
  Keywords (down) tropical rain; forest; population genetics; model SYMFOR; eco-gene; scaling up; competition  
  Abstract Understanding the effects of logging activity on genetic diversity is an important aspect of establishing the sustainability of selective logging management operations in tropical forests. Genetic variation is affected by selective logging directly, through the removal of and damage to trees within the population, and indirectly, through a change in the forest structure and environment in which the remaining population lives. Eco-Gene is a population genetics model applied to tropical forests over a scale of hundreds of hectares. SYMFOR is a modelling framework for individual-based spatially explicit ecological and management models applied to tropical forests over a scale of 0.25 4 ha. We have linked the models to enable simulations using processes involved in both models. To overcome problems of scale, the spatially explicit competition index calculated in SYMFOR simulations has been modelled such that it can be applied at scales representing much larger areas for which the data are not available, as required by Eco-Gene. The competition index is modelled as a distribution on a grid-square basis, and implemented in the linked Eco-Gene/SYMFOR system. Each tree within a grid-square is given a “relative competition” within the distribution, biased according to species. A competition index value is obtained for the tree by transforming the grid-square distribution to be relevant to the size of the tree, and extracting a value according to the tree's relative competition within the distribution. The distribution and each tree's relative competition within it change according to the effects of growth, mortality and logging activity. The model was calibrated using data from the Tapajos region of the Eastern Amazon forest. This paper describes the model, its calibration and validation and the implications of scaling up from an explicit representation to a modelled quantity. (C) 2004 Elsevier B.V. All rights reserved.  
  Address Embrapa Amazonia Oriental, BR-66095100 Belem, Para, Brazil, Email: paul.phillips@envams.co.uk  
  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 0304-3800 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000224635700012 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 234  
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Author Dezerald, O.; Céréghino, R.; Corbara, B.; Dejean, A.; Leroy, C. url  openurl
  Title Temperature: Diet Interactions Affect Survival through Foraging Behavior in a Bromeliad-Dwelling Predator Type Journal Article
  Year 2015 Publication Biotropica Abbreviated Journal Biotropica  
  Volume 47 Issue 5 Pages 569-578  
  Keywords (down) Toxorhynchites haemorrhoidalis; Biocontrol agent; Development; French Guiana; Selective feeding behavior; Tank bromeliad  
  Abstract Temperature, food quantity and quality play important roles in insect growth and survival, influencing population dynamics as well as interactions with other community members. However, the interaction between temperature and diet and its ecological consequences have been poorly documented. Toxorhynchites are well-known biocontrol agents for container-inhabiting mosquito larvae. We found that Toxorhynchites haemorrhoidalis larvae (Diptera: Culicidae) inhabiting water-filled rosettes of tank bromeliads catch and eat prey of both aquatic (mosquito larvae) and terrestrial origin (ants), using distinct predatory methods. They carried out frontal attacks on ants, but ambushed mosquito larvae. In choice tests, T. haemorrhoidalis favored terrestrial prey. Temperature had a significant effect on predator development and survival through its interaction with diet, but did not alter the preference for ants. T. haemorrhoidalis larvae emerged quickly when fed only mosquito larvae, whereas all individuals died before pupation when fed only ants. We conclude that behavioral factors (i.e., attraction to ants that disturb the surface of the water) overtake physiological factors (i.e., the adverse outcome of elevated temperature and an ant-based diet) in determining a predator's response to temperature:diet interactions. Finally, because T. haemorrhoidalis larvae preferentially feed on terrestrial insects in tank bromeliads, mosquito larvae may indirectly benefit from predation release. © 2015 Association for Tropical Biology and Conservation Inc.  
  Address UMR AMAP (botAnique et Modelisation de l'Architecture des Plantes et des vegetations), IRD, Boulevard de la Lironde, TA A-51/PS2, Montpellier Cedex 5, France  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
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  Notes Export Date: 17 September 2015 Approved no  
  Call Number EcoFoG @ webmaster @ Serial 624  
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Author Odonne, G.; Bourdy, G.; Beauchene, J.; Houel, E.; Stien, D.; Chevolot, L.; Deharo, E. openurl 
  Title From Tonic-cups to Bitter-cups: Kwasi bita beker from Suriname Determination, past and present use of an ancient galenic artefact Type Journal Article
  Year 2007 Publication Journal of Ethnopharmacology Abbreviated Journal J. Ethnopharmacol.  
  Volume 110 Issue 2 Pages 318-322  
  Keywords (down) Tonic-cup; Bitter-cup; Quassia amara; Suriname; traditional remedy  
  Abstract In the main markets of Paramaribo (Suriname), many stands offer what is locally called “Bitter-cups”, or “Kwasi bita beker”, small footed-cups, roughly carved from a whitish wood. The use of these cups is strictly medicinal and it seems to be restricted to Suriname, as they are not found in neighbouring countries (Guyana, French Guiana). The aim of this study was to identify the botanical origin of Bitter-cups still in use in the Saramaka traditional medicine (as information from field people was controversial), and document the ethnopharmacology of this original galenical artefact. Microscopic and high performance liquid chromatography (HPLC) analyses were carried out on Bitter-cup, and anatomical criteria (marginal parenchyma band, size of intervessel and vessel-ray pits, rays width and rays composition, vessels clustering, frequency and size of parenchyma pits) together with HPLC profiles of the macerates showed that the wood cup was similar to Quassia amara L. (Simaroubaceae) wood. Ethnopharmacological investigation indicates that the use of these cups is simply due to the pharmacological properties attributed to “bitters”, and is strongly linked to tradition and cultural attitudes. This study also emphasizes the long lasting use of these cups, now restricted to Suriname only, with almost no variation over one century. (c) 2006 Elsevier Ireland Ltd. All rights reserved.  
  Address Univ Toulouse 3, Ctr IRD, UMR 152, F-97323 Cayenne, France, Email: genevieve.bourdy@ird.fr  
  Corporate Author Thesis  
  Publisher ELSEVIER IRELAND LTD Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0378-8741 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000245486900012 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 166  
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Author Boisse, P.; Aimene, Y.; Dogui, A.; Dridi, S.; Gatouillat, S.; Hamila, N.; Khan, M.A.; Mabrouki, T.; Morestin, F.; Vidal-Sallé, E. doi  openurl
  Title Hypoelastic, hyperelastic, discrete and semi-discrete approaches for textile composite reinforcement forming Type Journal Article
  Year 2010 Publication International Journal of Material Forming Abbreviated Journal  
  Volume 3 Issue Supplement 2 Pages 1229-1240  
  Keywords (down) Textile composites Forming simulations Continuous/discrete approaches Hyperelasticity Hypoelasticity Semi-discrete finite element  
  Abstract The clear multi-scale structure of composite textile reinforcements leads to develop continuous and discrete approaches for their forming simulations. In this paper two continuous modelling respectively based on a hypoelastic and hyperelastic constitutive model are presented. A discrete approach is also considered in which each yarn is modelled by shell finite elements and where the contact with friction and possible sliding between the yarns are taken into account. Finally the semi-discrete approach is presented in which the shell finite element interpolation involves continuity of the displacement field but where the internal virtual work is obtained as the sum of tension, in-plane shear and bending ones of all the woven unit cells within the element. The advantages and drawbacks of the different approaches are discussed.  
  Address  
  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 Hypoelastic, hyperelastic, discrete and semi-discrete approaches for textile composite reinforcement forming Approved no  
  Call Number EcoFoG @ eric.marcon @ 8 Serial 90  
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Author Ruelle, J.; Yoshida, M.; Clair, B.; Thibaut, B. openurl 
  Title Peculiar tension wood structure in Laetia procera (Poepp.) Eichl. (Flacourtiaceae) Type Journal Article
  Year 2007 Publication Trees-Structure and Function Abbreviated Journal Trees-Struct. Funct.  
  Volume 21 Issue 3 Pages 345-355  
  Keywords (down) tension wood; tropical rainforest species; UV microspectrophotometry; scanning electron microscopy; cellulose microfibril angle  
  Abstract Tension wood of Laetia procera (Poepp.) Eichl. (Flacourtiaceae), a neo-tropical forest species, shows a peculiar secondary wall structure, with an alternance of thick and thin layers, while opposite wood of this species has a typical secondary wall structure (S1 + S2 + S3). Samples for the study of microstructural properties were collected upon the estimation of growth stresses in the living tree, in order to analyze the correlation of the former with the latter. Investigation using optical microscopy, scanning electron microscopy and UV microspectrophotometry allowed the description of the anatomy, ultra-structure and chemistry of this peculiar polylaminate secondary wall. In the thick layers, cellulose microfibril angle is very low (i.e., microfibril orientation is close to fibre axis) and cellulose microfibrils are well organized and parallel to each other. In the thin layers, microfibrils (only observable in the inner layer) are less organized and are oriented with a large angle relative to the axis of the cell. Thick layers are lightly lignified although thin layers show a higher content of lignin, close to that of opposite wood secondary wall. The more the wood was under tensile stress, the less the secondary wall was lignified, and lower the syringyl on guaiacyl lignin units' ratio was. The innermost layer of the secondary wall looks like a typical S3 layer with large microfibril angle and lignin occurrence. The interest of this kind of structure for the understanding of stress generation is discussed.  
  Address UMR EcoFoG, Kourou 97387, French Guiana, Email: ruelle_j@kourou.cirad.fr  
  Corporate Author Thesis  
  Publisher SPRINGER Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0931-1890 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000246206200009 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 163  
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Author Ruelle, J.; Beauchene, J.; Thibaut, A.; Thibaut, B. openurl 
  Title Comparison of physical and mechanical properties of tension and opposite wood from ten tropical rainforest trees from different species Type Journal Article
  Year 2007 Publication Annals of Forest Science Abbreviated Journal Ann. For. Sci.  
  Volume 64 Issue 5 Pages 503-510  
  Keywords (down) tension wood; opposite wood; tropical rainforest; physical and mechanical properties  
  Abstract On 10 trees from 10 species of French Guyana tropical rainforest in a clear active process of restoring verticality growth strains were measured in situ in order to determine the occurrence of tension wood within samples. Wood specimens were cut in the vicinity of the growth strains measurements in order to measure some mechanical and physical properties. As suspected, tensile growth strains was very much higher in tension wood zone, because longitudinal modulus of elasticity was slightly higher. Longitudinal shrinkage was also much higher in tension wood than in opposite wood.  
  Address UMR EcoFoG, Kourou 97387, Guyana, Email: ruelle@nuagr1.agr.nagoya-u.ac.jp  
  Corporate Author Thesis  
  Publisher EDP SCIENCES S A Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1286-4560 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000248098600003 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 160  
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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 (down) 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 0928-1541 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000242437400001 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 171  
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Author Niamke, F.B.; Amusant, N.; Charpentier, J.P.; Chaix, G.; Baissac, Y.; Boutahar, N.; Adima, A.A.; Kati-Coulibaly, S.; Jay-Allemand, C. openurl 
  Title Relationships between biochemical attributes (non-structural carbohydrates and phenolics) and natural durability against fungi in dry teak wood (Tectona grandis L. f.) Type Journal Article
  Year 2011 Publication Annals of Forest Science Abbreviated Journal Ann. For. Sci.  
  Volume 68 Issue 1 Pages 201-211  
  Keywords (down) Tectona grandis; Teak heartwood; Phenolic compound; Non-structural carbohydrate; Natural durability  
  Abstract Introduction Non-structural carbohydrates and phenolic compounds are implicated in the natural durability of wood. In order to find the chemical traits of natural durability in teak wood, the radial distribution of phenolics compounds and non-structural carbohydrates were studied in trees ranked by contrasting natural durability class against Antrodia sp. Methods Non-structural carbohydrates were analyzed by spectrophotometry after enzymatic assays and phenolics compounds using HPLC. Results High concentrations of starch, sucrose, glucose, and fructose were found in the sapwood, whereas only trace amounts were found in the heartwood. In the sapwood, low concentrations of H1 (a hydroxycinnamic acid derivative) were specifically detected. Tectoquinone was also detected in the sapwood but its content increased dramatically in the heartwood. 2-(Hydroxymethyl) anthraquinone and P1, an unidentified compound, were only detected in the heartwood and at high concentrations (>3 mg equivalent 5-methoxyflavone g(-1) dry weight. Lower concentrations of 1,4-naphthoquinone, anthraquinone-2-carboxylic acid, and lapachol were also only detected in the heartwood. H1 and tectoquinone present in the sapwood could be considered as phenolic precursors of the synthesis of heartwood toxic phenolics in the heartwood. Conclusion Correlations between natural durability and chemical composition of heartwood (quinone derivatives, P1, and non-structural carbohydrates) suggest that P1, 2-(hydroxymethyl) anthraquinone and tectoquinone could be natural durability traits. Heartwood extractives,  
  Address [Niamke, FB; Baissac, Y; Jay-Allemand, C] Univ Montpellier 2, F-34095 Montpellier 05, France, Email: Christian.jay-allemand@univ-montp2.fr  
  Corporate Author Thesis  
  Publisher Springer France Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1286-4560 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000290447600021 Approved no  
  Call Number EcoFoG @ webmaster @ Serial 340  
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