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Author Castro, H.; Fortunel, C.; Freitas, H. openurl 
  Title Effects of land abandonment on plant litter decomposition in a Montado system: relation to litter chemistry and community functional parameters Type Journal Article
  Year 2010 Publication Plant and Soil Abbreviated Journal Plant Soil  
  Volume 333 Issue 1-2 Pages 181-190  
  Keywords Ecosystem processes; Land use change; Leaf dry matter content; Life form; Litter quality; Mediterranean  
  Abstract Changes in land use and subsequent shifts in vegetation can influence decomposition through changes in litter quality (chemistry and structure) and alterations of soil temperature and moisture. Our aim was to study the effects of land abandonment on litter decomposition in a Mediterranean area of Montado, South Portugal. We tested the hypothesis that decomposition tends to slow down with abandonment, as woody species, richer in lignified structures, replace herbaceous species. We assessed the decomposition of community litter in situ using litterbag technique. To test the influence of local conditions, we simultaneously incubated a standard litter in situ. Our results showed that the shift from herbaceous to shrub-dominated communities lead to decreased decomposition rates. Changes in litter decomposition were primarily driven by changes in litter quality, even though the uneven pattern of litter mass loss over the experiment might reveal an effect from possible differences in microclimate. Shrub litter had higher nutrient content than herbaceous litter, which seemed to favour higher initial decomposition rates, but lower decomposition rate in the longer term. Shrubs also contribute to woody litter, richer in lignin, and secondary compounds that retard decomposition, and may play a role in increasing pools of slowly decomposing organic matter.  
  Address (up) [Castro, Helena; Freitas, Helena] Univ Coimbra, Dept Life Sci, Ctr Funct Ecol, P-3001401 Coimbra, Portugal, Email: hecastro@ci.uc.pt  
  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 0032-079X ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000280089400015 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 49  
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Author Cereghino, R.; Leroy, C.; Carrias, J.F.; Pelozuelo, L.; Segura, C.; Bosc, C.; Dejean, A.; Corbara, B. openurl 
  Title Ant-plant mutualisms promote functional diversity in phytotelm communities Type Journal Article
  Year 2011 Publication Functional Ecology Abbreviated Journal Funct. Ecol.  
  Volume 25 Issue 5 Pages 954-963  
  Keywords ant gardens; biodiversity; bromeliads; community functions; forest; French Guiana; invertebrates; phytotelmata; two-species mutualism  
  Abstract 1. Our understanding of the contribution of interspecific interactions to functional diversity in nature lags behind our knowledge of spatial and temporal patterns. Although two-species mutualisms are found in all types of ecosystems, the study of their ecological influences on other community members has mostly been limited to third species, while their influence on entire communities remains largely unexplored. 2. We hypothesized that mutualistic interactions between two respective ant species and an epiphyte mediate the biological traits composition of entire invertebrate communities that use the same host plant, thereby affecting food webs and functional diversity at the community level. 3. Aechmea mertensii (Bromeliaceae) is both a phytotelm ('plant-held water') and an ant-garden epiphyte. We sampled 111 bromeliads (111 aquatic invertebrate communities) associated with either the ant Pachycondyla goeldii or Camponotus femoratus. The relationships between ants, bromeliads and invertebrate abundance data were examined using a redundancy analysis. Biological traits information for invertebrates was structured using a fuzzy-coding technique, and a co-inertia analysis between traits and abundance data was used to interpret functional differences in bromeliad ecosystems. 4. The vegetative traits of A. mertensii depended on seed dispersion by C. femoratus and P. goeldii along a gradient of local conditions. The ant partner selected sets of invertebrates with traits that were best adapted to the bromeliads' morphology, and so the composition of the biological traits of invertebrate phytotelm communities depends on the identity of the ant partner. Biological traits suggest a bottom-up control of community structure in C. femoratus-associated phytotelmata and a greater structuring role for predatory invertebrates in P. goeldii-associated plants. 5. This study presents new information showing that two-species mutualisms affect the functional diversity of a much wider range of organisms. Most biological systems form complex networks where nodes (e. g. species) are more or less closely linked to each other, either directly or indirectly, through intermediate nodes. Our observations provide community-level information about biological interactions and functional diversity, and perspectives for further observations intended to examine whether large-scale changes in interacting species/community structure over broad geographical and anthropogenic gradients affect ecosystem functions.  
  Address (up) [Cereghino, R; Pelozuelo, L; Segura, C; Bosc, C] Univ Toulouse, EcoLab, Lab Ecol Fonct & Environm, UMR 5245, F-31062 Toulouse, France, Email: cereghin@cict.fr  
  Corporate Author Thesis  
  Publisher Wiley-Blackwell 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 WOS:000295132100003 Approved no  
  Call Number EcoFoG @ webmaster @ Serial 341  
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Author Cereghino, R.; Leroy, C.; Dejean, A.; Corbara, B. openurl 
  Title Ants mediate the structure of phytotelm communities in an ant-garden bromeliad Type Journal Article
  Year 2010 Publication Ecology Abbreviated Journal Ecology  
  Volume 91 Issue 5 Pages 1549-1556  
  Keywords Aechmea mertensii; ant-gardens; biodiversity; bromeliads; Camponotus femoratus; Crematogaster levior; macroinvertebrates; mutualism; Pachycondyla goeldii; phytotelmata; secondary forest; Sinnamary; French Guiana; species interactions  
  Abstract The main theories explaining the biological diversity of rain forests often confer a limited understanding of the contribution of interspecific interactions to the observed patterns. We show how two-species mutualisms can affect much larger segments of the invertebrate community in tropical rain forests. Aechmea mertensii (Bromeliaceae) is both a phytotelm (plant-held water) and an ant-garden epiphyte. We studied the influence of its. associated ant species (Pachycondyla goeldii and Camponotus femoratus) on the physical characteristics of the plants, and, subsequently, on the diversity of the invertebrate communities that inhabit their tanks. As dispersal agents for the bromeliads, P. goeldii and C. femoratus influence the shape and size of the bromeliad by determining the location of the seedling, from exposed to partially shaded areas. By coexisting on a local scale, the two ant species generate a gradient of habitat conditions in terms of available resources (space and food) for aquatic invertebrates, the diversity of the invertebrate communities increasing with greater volumes of water and fine detritus. Two-species mutualisms are widespread in nature, but their influence on the diversity of entire communities remains largely unexplored. Because macroinvertebrates constitute an important part of animal production in all ecosystem types, further investigations should address the functional implications of such indirect effects.  
  Address (up) [Cereghino, Regis] Univ Toulouse, UPS, INPT, Lab Ecol Fonct,EcoLab, F-31062 Toulouse, France, Email: cereghin@cict.fr  
  Corporate Author Thesis  
  Publisher ECOLOGICAL SOC AMER Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0012-9658 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000277867600030 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 59  
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Author Chang, S.S.; Clair, B.; Ruelle, J.; Beauchene, J.; Di Renzo, F.; Quignard, F.; Zhao, G.J.; Yamamoto, H.; Gril, J. openurl 
  Title Mesoporosity as a new parameter for understanding tension stress generation in trees Type Journal Article
  Year 2009 Publication Journal of Experimental Botany Abbreviated Journal J. Exp. Bot.  
  Volume 60 Issue 11 Pages 3023-3030  
  Keywords Growth stress; hydrogel; mesoporosity; tension wood  
  Abstract The mechanism for tree orientation in angiosperms is based on the production of high tensile stress on the upper side of the inclined axis. In many species, the stress level is strongly related to the presence of a peculiar layer, called the G-layer, in the fibre cell wall. The structure of the G-layer has recently been described as a hydrogel thanks to N-2 adsorption-desorption isotherms of supercritically dried samples showing a high mesoporosity (pores size from 2-50 nm). This led us to revisit the concept of the G-layer that had been, until now, only described from anatomical observation. Adsorption isotherms of both normal wood and tension wood have been measured on six tropical species. Measurements show that mesoporosity is high in tension wood with a typical thick G-layer while it is much less with a thinner G-layer, sometimes no more than normal wood. The mesoporosity of tension wood species without a G-layer is as low as in normal wood. Not depending on the amount of pores, the pore size distribution is always centred around 6-12 nm. These results suggest that, among species producing fibres with a G-layer, large structural differences of the G-layer exist between species.  
  Address (up) [Chang, Shan-Shan; Clair, Bruno; Gril, Joseph] Univ Montpellier 2, LMGC, CNRS, F-34095 Montpellier 5, France, Email: clair@lmgc.univ-montp2.fr  
  Corporate Author Thesis  
  Publisher OXFORD UNIV PRESS Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0022-0957 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000268588300008 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 107  
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Author Chave, J.; Navarrete, D.; Almeida, S.; Alvarez, E.; Aragao, L.E.O.C.; Bonal, D.; Chatelet, P.; Silva-Espejo, J.E.; Goret, J.Y.; von Hildebrand, P.; Jimenez, E.; Patino, S.; Penuela, M.C.; Phillips, O.L.; Stevenson, P.; Malhi, Y. openurl 
  Title Regional and seasonal patterns of litterfall in tropical South America Type Journal Article
  Year 2010 Publication Biogeosciences Abbreviated Journal Biogeosciences  
  Volume 7 Issue 1 Pages 43-55  
  Keywords  
  Abstract The production of aboveground soft tissue represents an important share of total net primary production in tropical rain forests. Here we draw from a large number of published and unpublished datasets (n=81 sites) to assess the determinants of litterfall variation across South American tropical forests. We show that across old-growth tropical rainforests, litterfall averages 8.61 +/- 1.91 Mg ha(-1) yr(-1) (mean +/- standard deviation, in dry mass units). Secondary forests have a lower annual litterfall than old-growth tropical forests with a mean of 8.01 +/- 3.41 Mg ha(-1) yr(-1). Annual litterfall shows no significant variation with total annual rainfall, either globally or within forest types. It does not vary consistently with soil type, except in the poorest soils (white sand soils), where litterfall is significantly lower than in other soil types (5.42 +/- 1.91 Mg ha(-1) yr(-1)). We also study the determinants of litterfall seasonality, and find that it does not depend on annual rainfall or on soil type. However, litterfall seasonality is significantly positively correlated with rainfall seasonality. Finally, we assess how much carbon is stored in reproductive organs relative to photosynthetic organs. Mean leaf fall is 5.74 +/- 1.83 Mg ha(-1) yr(-1) (71% of total litterfall). Mean allocation into reproductive organs is 0.69 +/- 0.40 Mg ha(-1) yr(-1) (9% of total litterfall). The investment into reproductive organs divided by leaf litterfall increases with soil fertility, suggesting that on poor soils, the allocation to photosynthetic organs is prioritized over that to reproduction. Finally, we discuss the ecological and biogeochemical implications of these results.  
  Address (up) [Chave, J.] CNRS UPS, Lab Evolut & Divers Biol, UMR 5174, Toulouse, France, Email: chave@cict.fr  
  Corporate Author Thesis  
  Publisher COPERNICUS GESELLSCHAFT MBH Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1726-4170 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000274058100004 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 70  
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Author Chevolot, M.; Louisanna, E.; Azri, W.; Leblanc-Fournier, N.; Roeckel-Drevet, P.; Scotti-Saintagne, C.; Scotti, I. openurl 
  Title Isolation of primers for candidate genes for mechano-sensing in five Neotropical tree species Type Journal Article
  Year 2011 Publication Tree Genetics & Genomes Abbreviated Journal Tree Genet. Genomes  
  Volume 7 Issue 3 Pages 655-661  
  Keywords Population genomics; Functional gene; Mechanical signals; Fabaceae  
  Abstract Mechanical signals have an impact on plant development. Tropical rainforest trees display large variability for life-history traits related to biomechanics and therefore are a unique study system to better understand biomechanical trait variability from an evolutionary perspective. From sequences and gene expression data available in model species, we developed specific primers for six candidate genes for mechano-sensing in five tropical species. Most of the gene sequences were polymorphic in most species.  
  Address (up) [Chevolot, Malia; Louisanna, Eliane; Scotti-Saintagne, Caroline; Scotti, Ivan] INRA, Unite Mixte Rech Ecol Forets Guyane, Kourou 97310, French Guiana, Email: ivan.scotti@ecofog.gf  
  Corporate Author Thesis  
  Publisher Springer Heidelberg Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1614-2942 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000290571900018 Approved no  
  Call Number EcoFoG @ webmaster @ Serial 315  
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Author Christensen-Dalsgaard, K.K.; Ennos, A.R.; Fournier, M. openurl 
  Title Are radial changes in vascular anatomy mechanically induced or an ageing process? Evidence from observations on buttressed tree root systems Type Journal Article
  Year 2008 Publication Trees-Structure and Function Abbreviated Journal Trees-Struct. Funct.  
  Volume 22 Issue 4 Pages 543-550  
  Keywords wood; anatomy; mechanical loading; tree development; vessels  
  Abstract To investigate the effect of changes in mechanical loading conditions on radial anatomical patterns, we here compare the trunk with the roots in two locations of three species of buttressed trees. The proximal part of the buttress roots is highly mechanically loaded throughout juvenile growth whereas the distal part of the buttresses is though to be mechanically unimportant at formation but become progressively more mechanically loaded during growth. We measured the frequency and diameter of the vessels and the vessel area fraction, and from this calculated the specific conductivity of tissue samples of the core-, intermediate- and outer wood. As in previous studies there was an increase in vessel size, vessel area fraction and specific conductivity from the pith to the bark in the trunk. In the proximal part of the buttress roots, however, there was no increase in vessel size and conductivity from core wood and out in agreement with the high mechanical loading found here throughout growth. There was instead a decrease in vessel size, vessel area fraction and specific conductivity from core- to outer wood in the distal part of the buttress roots in accordance with the increase in mechanical loading. Hence, it appears that the radial anatomical patterns are not a passive function of cambial ageing but may be modified in response to local mechanical loading.  
  Address (up) [Christensen-Dalsgaard, Karen K.] Univ Alberta, Edmonton, AB T6G 2E3, Canada, Email: kkchrist@ualberta.ca  
  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:000257385200014 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 136  
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Author Conte, D.E.; Aboulaich, A.; Robert, F.; Olivier-Fourcade, J.; Jumas, J.C.; Jordy, C.; Willmann, P. openurl 
  Title Sn-x[BPO4](1-x) composites as negative electrodes for lithium ion cells: Comparison with amorphous SnB0.6P0.4O2.9 and effect of composition Type Journal Article
  Year 2010 Publication Journal of Solid State Chemistry Abbreviated Journal J. Solid State Chem.  
  Volume 183 Issue 1 Pages 65-75  
  Keywords Sn-based composites; Lithium-ion batteries; Negative electrodes; Mossbauer spectroscopy; LixSn alloys  
  Abstract A comparative study of two Sn-based composite materials as negative electrode for Li-ion accumulators is presented. The former SnB0.6P0.4O2.9 obtained by in-situ dispersion of SnO in an oxide matrix is shown to be an amorphous tin composite oxide (ATCO). The latter Sn-0.72[BPO4](0.28) obtained by ex-situ dispersion of Sri in a borophosphate matrix consists of Sri particles embedded in a crystalline BPO4 matrix. The electrochemical responses of ATCO and Sn-0.72.[BPO4](0.28) composite in galvanostatic mode show reversible capacities of about 450 and 530 mAhg(-1), respectively, with different irreversible capacities (60% and 29%). Analysis of these composite materials by Sn-119 Mossbauer spectroscopy in transmission (TMS) and emission (CEMS) modes confirms that ATCO is an amorphous Sn-II composite oxide and shows that in the case of Sn-0.72[BPO4](0.28), the Surface of the tin clusters is mainly formed by Sn-II in an amorphous interface whereas the bulk of the clusters is mainly formed by Sn-0. The determination of the recoilless free fractions f (Lamb-Mossbauer factors) leads to the effective fraction of both Sn-0 and Sn-II species in such composites. The influence of chemical composition and especially of the surface-to-bulk tin species ratio oil the electrochemical behaviour has been analysed for several Sn-x[BPO4](1-x) composite materials (0.17 < x < 0.91). The cell using the compound Sn-0.72[BPO4](0.28) as active material exhibits interesting electrochemical performances (reversible capacity of 500 mAh g(-1) at C/5 rate). (C) 2009 Elsevier Inc. All rights reserved.  
  Address (up) [Conte, Donato Ercole; Aboulaich, Abdelmaula; Robert, Florent; Olivier-Fourcade, Josette; Jumas, Jean-Claude] Univ Montpellier 2, CNRS, UMR 5253,Inst Charles Gerhardt, Equipe Agregats Interfaces & Mat Energie, F-34095 Montpellier, France, Email: iguanasornione@libero.it  
  Corporate Author Thesis  
  Publisher ACADEMIC PRESS INC ELSEVIER SCIENCE Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0022-4596 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000273834600010 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 83  
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Author Coq, S.; Weigel, J.; Butenschoen, O.; Bonal, D.; Hattenschwiler, S. openurl 
  Title Litter composition rather than plant presence affects decomposition of tropical litter mixtures Type Journal Article
  Year 2011 Publication Plant and Soil Abbreviated Journal Plant Soil  
  Volume 343 Issue 1-2 Pages 273-286  
  Keywords Amazonian lowland rainforest; Belowground/aboveground interactions; Litter decomposition; Non-additive effect; Nitrogen dynamic; Plant-soil feedback  
  Abstract Litter decomposition is strongly controlled by litter quality, but the composition of litter mixtures and potential interactions with live plants through root activity may also influence decomposers. In a greenhouse experiment in French Guiana we studied the combined effects of the presence of tropical tree seedlings and of distinct litter composition on mass and nitrogen (N) loss from decomposing litter and on microbial biomass. Different litter mixtures decomposed for 435 days in pots filled with sand and containing an individual seedling from one of four different tree species. We found both additive and negative non-additive effects (NAE) of litter mixing on mass loss, whereas N loss showed negative and positive NAE of litter mixing. If litter from the two tree species, Platonia insignis and Goupia glabra were present, litter mixtures showed more positive and more negative NAE on N loss, respectively. Overall, decomposition, and in particular non-additive effects, were only weakly affected by the presence of tree seedlings. Litter mass loss weakly yet significantly decreased with increasing fine root biomass in presence of Goupia seedlings, but not in the presence of seedlings of any other tree species. Our results showed strong litter composition effects and also clear, mostly negative, non-additive effects on mass loss and N loss. Species identity of tree seedlings can modify litter decomposition, but these live plant effects remain quantitatively inferior to litter composition effects.  
  Address (up) [Coq, Sylvain; Haettenschwiler, Stephan] CNRS, CEFE, F-34293 Montpellier 5, France, Email: sylvain.coq@gmail.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 0032-079x ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000290688000020 Approved no  
  Call Number EcoFoG @ webmaster @ Serial 320  
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Author Coste, S.; Roggy, J.C.; Schimann, H.; Epron, D.; Dreyer, E. pdf  openurl
  Title A cost-benefit analysis of acclimation to low irradiance in tropical rainforest tree seedlings: leaf life span and payback time for leaf deployment Type Journal Article
  Year 2011 Publication Journal of Experimental Botany Abbreviated Journal J. Exp. Bot.  
  Volume 62 Issue 11 Pages 3941-3955  
  Keywords Carbon balance; construction cost; functional diversity; leaf life span; payback time; photosynthesis; tropical rainforest  
  Abstract The maintenance in the long run of a positive carbon balance under very low irradiance is a prerequisite for survival of tree seedlings below the canopy or in small gaps in a tropical rainforest. To provide a quantitative basis for this assumption, experiments were carried out to determine whether construction cost (CC) and payback time for leaves and support structures, as well as leaf life span (i) differ among species and (ii) display an irradiance-elicited plasticity. Experiments were also conducted to determine whether leaf life span correlates to CC and payback time and is close to the optimal longevity derived from an optimization model. Saplings from 13 tropical tree species were grown under three levels of irradiance. Specific-CC was computed, as well as CC scaled to leaf area at the metamer level. Photosynthesis was recorded over the leaf life span. Payback time was derived from CC and a simple photosynthesis model. Specific-CC displayed only little interspecific variability and irradiance-elicited plasticity, in contrast to CC scaled to leaf area. Leaf life span ranged from 4 months to > 26 months among species, and was longest in seedlings grown under lowest irradiance. It was always much longer than payback time, even under the lowest irradiance. Leaves were shed when their photosynthesis had reached very low values, in contrast to what was predicted by an optimality model. The species ranking for the different traits was stable across irradiance treatments. The two pioneer species always displayed the smallest CC, leaf life span, and payback time. All species displayed a similar large irradiance-elicited plasticity.  
  Address (up) [Coste, S; Epron, D; Dreyer, E] INRA, UMR1137, Ctr INRA Nancy, F-54280 Champenoux, France, Email: dreyer@nancy.inra.fr  
  Corporate Author Thesis  
  Publisher Oxford Univ Press Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0022-0957 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000292838700021 Approved no  
  Call Number EcoFoG @ webmaster @ Serial 331  
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