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Author Schimann, H.; Joffre, R.; Roggy, J.C.; Lensi, R.; Domenach, A.M. openurl 
  Title Evaluation of the recovery of microbial functions during soil restoration using near-infrared spectroscopy Type Journal Article
  Year 2007 Publication Applied Soil Ecology Abbreviated Journal Appl. Soil Ecol.  
  Volume 37 Issue 3 Pages 223-232  
  Keywords NIRS; microbial activities; respiration; denitrification; carbon; nitrogen; soil functioning; restoration  
  Abstract Microbial-based indicators, such as C and N contents or microbial functions involved in C and N cycles, are currently used to describe the status of soils in disturbed areas. Microbial functions are more accurate indicators but their measurement for studies at the ecosystem level remains problematical because of the huge spatial variability of these processes and, consequently, of the large number of soil samples which must be analyzed. Our goal was to test the capacity of near-infrared reflectance spectroscopy (NIRS) to predict respiration and denitrification but also carbon and nitrogen contents of soils submitted to various procedures of restoration. To achieve this objective, we took advantage of an experiment conducted on a reforestation system established after open-cast gold mining in French Guiana. In this experimental station, plantations of various ages and various soil textures were at our disposal. Our results showed that both plantations and soil texture had a strong impact on the recovery of soil functioning: carbon and nitrogen contents, respiration and denitrification increased with age of plantation and clay content. Calibrations were performed between spectral data and microbial-based indicators using partial least squares regression (PLS). The results showed that C and N contents were accurately predicted. Microbial functions were less precisely predicted with results more accurate on clayey soils than on sandy soils. In clayey soils, perturbed or restored soils and the year of plantation were discriminated very efficiently through principal component analyses of spectral signatures (over 80% of variance explained on the first two axes). Near-infrared spectroscopy may thus be extended to the prediction of functional soil parameters, but the capacity of this method must be strengthened by expending the databases with other soils in other contexts. The possibility of using NIRS provides many opportunities for understanding both the temporal dynamics and the spatial variability of the recovery of key microbial functions during soil restoration. (c) 2007 Elsevier B.V. All rights reserved.  
  Address UMR EcoFoG, Kourou 97387, French Guiana, Email: heidy.schimann@cirad.fr  
  Corporate Author Thesis  
  Publisher ELSEVIER SCIENCE BV Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0929-1393 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000250668000006 Approved no  
  Call Number (up) EcoFoG @ eric.marcon @ Serial 154  
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Author Fang, C.H.; Clair, B.; Gril, J.; Almeras, T. openurl 
  Title Transverse shrinkage in G-fibers as a function of cell wall layering and growth strain Type Journal Article
  Year 2007 Publication Wood Science and Technology Abbreviated Journal Wood Sci. Technol.  
  Volume 41 Issue 8 Pages 659-671  
  Keywords  
  Abstract Transverse drying shrinkage was measured at microscopic and mesoscopic levels in poplar wood characterised by an increasing growth strain (GS), from normal to tension wood. Results show that: (a) the drying shrinkage, measured as a relative thickness decrease, was significantly higher for G-layer (GL) than for the other layers (OL), GL shrinkage was not significantly correlated with GS, and OL shrinkage was negatively correlated with GS. (b) In gelatinous fibre (G-fibre), lumen size increased during drying and this increase was positively related with GS, but in normal wood fibre, lumen size decreased during drying. These findings suggest that GL shrank outwards (i.e., its internal perimeter increases), so that its shrinkage weakly affected the total cell shrinkage and the mesoscopic shrinkage was controlled by the OL shrinkage which shrank inwards (i.e., its external perimeter decreases). (c) Measurements done on 7 x 7 mm(2) thin sections evidenced a negative correlation between transverse shrinkage and GS, significant in T direction but weak in R direction. These observations at both levels allow to discuss the contribution of GL to the mesoscopic shrinkage of tension wood.  
  Address Univ Montpellier 2, Lab Mech & Gene Civil, F-34095 Montpellier, France, Email: fang1979@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 0043-7719 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000250381500003 Approved no  
  Call Number (up) EcoFoG @ eric.marcon @ Serial 155  
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Author Christensen-Dalsgaard, K.K.; Fournier, M.; Ennos, A.R.; Barfod, A.S. openurl 
  Title Changes in vessel anatomy in response to mechanical loading in six species of tropical trees Type Journal Article
  Year 2007 Publication New Phytologist Abbreviated Journal New Phytol.  
  Volume 176 Issue 3 Pages 610-622  
  Keywords hydraulic architecture; hydraulic-mechanical trade-off; mechanical adaptation; rooting morphology; tropical trees; vascular anatomy  
  Abstract It is well known that trees adapt their supportive tissues to changes in loading conditions, yet little is known about how the vascular anatomy is modified in this process. We investigated this by comparing more and less mechanically loaded sections in six species of tropical trees with two different rooting morphologies. We measured the strain, vessel size, frequency and area fraction and from this calculated the specific conductivity, then measured the conductivity, modulus of elasticity and yield stress. The smallest vessels and the lowest vessel frequency were found in the parts of the trees subjected to the greatest stresses or strains. The specific conductivity varied up to two orders of magnitude between mechanically loaded and mechanically unimportant parts of the root system. A trade-off between conductivity and stiffness or strength was revealed, which suggests that anatomical alterations occur in response to mechanical strain. By contrast, between-tree comparisons showed that average anatomical features for the whole tree seemed more closely related to their ecological strategy.  
  Address Univ Manchester, Fac Life Sci, Manchester M60 1QD, Lancs, England, Email: karen@cd-mail.dk  
  Corporate Author Thesis  
  Publisher BLACKWELL PUBLISHING 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 ISI:000250275000013 Approved no  
  Call Number (up) EcoFoG @ eric.marcon @ Serial 156  
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Author Sierra, J.; Daudin, D.; Domenach, A.M.; Nygren, P.; Desfontaines, L. openurl 
  Title Nitrogen transfer from a legume tree to the associated grass estimated by the isotopic signature of tree root exudates: A comparison of the N-15 leaf feeding and natural N-15 abundance methods Type Journal Article
  Year 2007 Publication European Journal of Agronomy Abbreviated Journal Eur. J. Agron.  
  Volume 27 Issue 2-4 Pages 178-186  
  Keywords agroforestry; box model; gliricidia sepium; N-15 fractionation; root turnover; tree pruning  
  Abstract Nitrogen (N) transfer from legume trees to associated crops is a key factor for the N economy of low-input agroforestry systems. In this work, we presented a new approach to estimate N transfer based on the N-15 content of root exudates and N released by root turnover of the donor plant (Gliricidia sepium) and the temporal change of the N-15 content of the receiver plant (Dichanthium aristatum). The study was carried out in greenhouse using two isotopic methods: N-15 leaf feeding (LF) and the natural N-15 abundance (NA). Measurements of exudate N-15 were made at several dates before and after tree pruning. A time-dependent box model was devised to quantify N transfer in time and to make comparisons between the isotopic methods. In NA, although tree roots and exudates presented a similar N-15 signature before tree pruning, exudates were strongly depleted in N-15 after pruning. In LF, exudates were always depleted in N-15 in relation to tree roots. Hence, the current assumption used in N transfer studies concerning the equal N-15/N-14 distribution in tissues of the donor plant and in its excreted N was not confirmed in our study. Before pruning, N transfer functioned as a two-N-source system (soil N and exudates N) and both isotopic methods provided similar estimates: 11-12% for LF and 10-15% for NA. Calculations per-formed with the model indicated that N transfer occurred with small or nil fractionation of N-15 in exudates. After pruning, there was a third N source associated with N released from tree root turnover. During this period, the isotopic signature of the receiver plant showed a transient state due to the progressive decrease of N-15 content of that N source. The amount of N derived from the tree represented 65% of the total N content of the. grass at the end of the experiments. (c) 2007 Elsevier B.V. All rights reserved.  
  Address INRA, Unite Agropedioclimat, UR135, Petit Bourg 97170, Guadeloupe, Email: jorge.sierra@antilles.inra.fr  
  Corporate Author Thesis  
  Publisher ELSEVIER SCIENCE BV Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1161-0301 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000249798900003 Approved no  
  Call Number (up) EcoFoG @ eric.marcon @ Serial 157  
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Author Ollivier, M.; Baraloto, C.; Marcon, E. openurl 
  Title A trait database for Guianan rain forest trees permits intra- and inter-specific contrasts Type Journal Article
  Year 2007 Publication Annals of Forest Science Abbreviated Journal Ann. For. Sci.  
  Volume 64 Issue 7 Pages 781-786  
  Keywords plant traits; tropical forest; French Guiana; functional groups; plasticity; ontogeny  
  Abstract We present a plant trait database covering autecology for rain forest trees of French Guiana. The database comprises more than thirty traits including autecology (e. g., habitat associations and reproductive phenology), wood structure (e. g., density and tension characteristics) and physiology at the whole plant (e. g., carbon and nitrogen isotopes) and leaf level (e. g., specific leaf area, photosynthetic capacity). The current database describes traits for about nine hundred species from three hundred genera in one hundred families. For more than sixty species, data on twelve morphological and ecophysiological traits are provided for individual plants under different environmental conditions and at different ontogenetic stages. The database is thus unique in permitting intraspecific analyses, such as the effects of ontogenetic stages or environmental conditions on trait values and their relationships.  
  Address INRA, Unit Mixte Rech Ecol Forets Guyane, Kourou, France, Email: baraloto.c@kourou.cirad.fr  
  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:000250097700011 Approved no  
  Call Number (up) EcoFoG @ eric.marcon @ Serial 158  
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Author Baraloto, C.; Forget, P.M. openurl 
  Title Seed size, seedling morphology, and response to deep shade and damage in neotropical rain forest trees Type Journal Article
  Year 2007 Publication American Journal of Botany Abbreviated Journal Am. J. Bot.  
  Volume 94 Issue 6 Pages 901-911  
  Keywords cotyledons; French Guiana; functional morphology; herbivory; life history; phylogeny; regeneration strategy; shade tolerance  
  Abstract To investigate the existence of coordinated sets of seedling traits adapted to contrasting establishment conditions, we examined evolutionary convergence in seedling traits for 299 French Guianan woody plant species and the stress response in a shadehouse of species representing seed size gradients within five major cotyledon morphology types. The French Guianan woody plant community has larger seeds than other tropical forest communities and the largest proportion of hypogeal cotyledon type (59.2%) reported for tropical forests. Yet the community includes many species with intermediate size seeds that produce seedlings with different cotyledonal morphologies. A split-plot factorial design with two light levels (0.8% and 16.1% PAR) and four damage treatments (control, seed damage, leaf damage, stem damage) was used in the shadehouse experiment. Although larger-seeded species had higher survival and slower growth, these patterns were better explained by cotyledon type than by seed mass. Even larger-seeded species with foliar cotyledons grew faster than species with reserve-type cotyledons, and survival after stem grazing was five times higher in seedlings with hypogeal cotyledons than with epigeal cotyledons. Thus, to predict seedling performance using seed size, seedling morphology must also be considered.  
  Address Inst Natl Rech Agronom, UMR, Ecol Forets Guyane, Kourou, France, Email: baraloto.c@kourou.cirad.fr  
  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 0002-9122 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000249830600001 Approved no  
  Call Number (up) EcoFoG @ eric.marcon @ Serial 159  
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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 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 (up) EcoFoG @ eric.marcon @ Serial 160  
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Author Nasr, H.; Domenach, A.M.; Ghorbel, M.H.; Benson, D.R. openurl 
  Title Divergence in symbiotic interactions between same genotypic PCR-RFLP Frankia strains and different Casuarinaceae species under natural conditions Type Journal Article
  Year 2007 Publication Physiologia Plantarum Abbreviated Journal Physiol. Plant.  
  Volume 130 Issue 3 Pages 400-408  
  Keywords  
  Abstract The symbiotic interactions between Frankia strains and their associated plants from the Casuarinaceae under controlled conditions are well documented but little is known about these interactions under natural conditions. We explored the symbiotic interactions between eight genotypically characterized Frankia strains and five Casuarinaceae species in long-term field trials. Characterization of strains was performed using the polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP) for the nifD-nifK intergenic transcribed spacer (ITS) and 16S-23S ITS. Assessments of the symbiotic interactions were based on nodulation patterns using nodule dry weight and viability, and on actual N-2 fixation using the delta N-15 method. The PCR-RFLP patterns showed that the analyzed strains belonged to the same genotypic group (CeD group), regardless of the host species and environment of origin. The nodule viability index is introduced as a new tool to measure the viability of perennial nodules and to predict their effectiveness. The host Casuarinaceae species was a key factor influencing both the actual N-2-fixing activity of the associated Frankia strain and the viability of nodules within a location. This is the first study providing information on the symbiotic interactions between genotypically characterized Frankia strains and actinorhizal plants under natural conditions. The results revealed a way to improve a long-term management of the Casuarinaceae symbiosis.  
  Address Univ Connecticut, Dept Mol & Cell Biol, Storrs, CT 06279 USA, Email: david.benson@uconn.edu  
  Corporate Author Thesis  
  Publisher BLACKWELL PUBLISHING Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0031-9317 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000247206100010 Approved no  
  Call Number (up) EcoFoG @ eric.marcon @ Serial 161  
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Author Coutand, C.; Fournier, M.; Moulia, B. openurl 
  Title The gravitropic response of poplar trunks: Key roles of prestressed wood regulation and the relative kinetics of cambial growth versus wood maturation Type Journal Article
  Year 2007 Publication Plant Physiology Abbreviated Journal Plant Physiol.  
  Volume 144 Issue 2 Pages 1166-1180  
  Keywords  
  Abstract In tree trunks, the motor of gravitropism involves radial growth and differentiation of reaction wood (Archer, 1986). The first aim of this study was to quantify the kinematics of gravitropic response in young poplar (Populus nigra x Populus deltoides, 'I4551') by measuring the kinematics of curvature fields along trunks. Three phases were identified, including latency, upward curving, and an anticipative autotropic decurving, which has been overlooked in research on trees. The biological and mechanical bases of these processes were investigated by assessing the biomechanical model of Fournier et al. (1994). Its application at two different time spans of integration made it possible to test hypotheses on maturation, separating the effects of radial growth and cross section size from those of wood prestressing. A significant correlation between trunk curvature and Fournier's model integrated over the growing season was found, but only explained 32% of the total variance. Moreover, over a week's time period, the model failed due to a clear out phasing of the kinetics of radial growth and curvature that the model does not take into account. This demonstrates a key role of the relative kinetics of radial growth and the maturation process during gravitropism. Moreover, the degree of maturation strains appears to differ in the tension woods produced during the upward curving and decurving phases. Cell wall maturation seems to be regulated to achieve control over the degree of prestressing of tension wood, providing effective control of trunk shape.  
  Address Univ Clermont Ferrand, Inst Natl Recherche Agronom, Physiol Integree Arbre Fruitier, Unite Mixte Recherche 547, F-63100 Clermont Ferrand, France, Email: coutand@clermont.inra.fr  
  Corporate Author Thesis  
  Publisher AMER SOC PLANT BIOLOGISTS Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0032-0889 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000247075000055 Approved no  
  Call Number (up) EcoFoG @ eric.marcon @ Serial 162  
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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 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 (up) EcoFoG @ eric.marcon @ Serial 163  
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