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Author Veron, V.; Caron, H.; Degen, B.
Title Gene flow and mating system of the tropical tree Sextonia rubra Type Journal Article
Year 2005 Publication Silvae Genetica Abbreviated Journal Silvae Genet.
Volume 54 Issue 6 Pages 275-280
Keywords genetic diversity; gene flow; heterozygosity; microsatellites; mixed mating; tropical tree; twogener
Abstract In this paper we report a study of the mating system and gene flow of Sextonia rubra, a hermaphroditic, insect pollinated tropical tree species with a geographic distribution in the Guyana Plateau and the Amazon. Using five microsatellites we analysed 428 seeds of 27 open pollinated families at the experimental site “Paracou” in French Guiana. We observed, compared to other tropical tree species, a high level of genetic diversity. We estimated parameters of the mating system and gene flow by using the mixed mating model and the TwoGener approach. The estimated multilocus outcrossing rate, t(m), was 0.992 indicating nearly complete outcrossing. A significant level of biparental inbreeding and a:small proportion. of full-sibs were estimated for the 27 seed arrays. The differentiation of allelic frequencies among the pollen pools was (Phi(FT) = 0.061. We estimated mean pollen dispersal distances between 65 m and 89 m according to the dispersal models used. The joint estimation of pollen dispersal and density of reproductive trees gave an effective density estimate of 2.1-2.2 trees/ha.
Address INRA, UMR, ECOFOG, Kourou 9738, French Guiana, Email: b.degen@holz.uni-hamburg.de
Corporate Author Thesis
Publisher J D SAUERLANDERS VERLAG Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0037-5349 ISBN Medium
Area Expedition Conference
Notes (down) ISI:000235239400005 Approved no
Call Number EcoFoG @ eric.marcon @ Serial 182
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Author Hardy, O.J.; Maggia, L.; Bandou, E.; Breyne, P.; Caron, H.; Chevallier, M.H.; Doligez, A.; Dutech, C.; Kremer, A.; Latouche-Halle, C.; Troispoux, V.; Veron, V.; Degen, B.
Title Fine-scale genetic structure and gene dispersal inferences in 10 Neotropical tree species Type Journal Article
Year 2006 Publication Molecular Ecology Abbreviated Journal Mol. Ecol.
Volume 15 Issue 2 Pages 559-571
Keywords French Guiana; gene dispersal; seed dispersal; spatial genetic structure; tropical trees
Abstract The extent of gene dispersal is a fundamental factor of the population and evolutionary dynamics of tropical tree species, but directly monitoring seed and pollen movement is a difficult task. However, indirect estimates of historical gene dispersal can be obtained from the fine-scale spatial genetic structure of populations at drift-dispersal equilibrium. Using an approach that is based on the slope of the regression of pairwise kinship coefficients on spatial distance and estimates of the effective population density, we compare indirect gene dispersal estimates of sympatric populations of 10 tropical tree species. We re-analysed 26 data sets consisting of mapped allozyme, SSR (simple sequence repeat), RAPD (random amplified polymorphic DNA) or AFLP (amplified fragment length polymorphism) genotypes from two rainforest sites in French Guiana. Gene dispersal estimates were obtained for at least one marker in each species, although the estimation procedure failed under insufficient marker polymorphism, limited sample size, or inappropriate sampling area. Estimates generally suffered low precision and were affected by assumptions regarding the effective population density. Averaging estimates over data sets, the extent of gene dispersal ranged from 150 m to 1200 m according to species. Smaller gene dispersal estimates were obtained in species with heavy diaspores, which are presumably not well dispersed, and in populations with high local adult density. We suggest that limited seed dispersal could indirectly limit effective pollen dispersal by creating higher local tree densities, thereby increasing the positive correlation between pollen and seed dispersal distances. We discuss the potential and limitations of our indirect estimation procedure and suggest guidelines for future studies.
Address Univ Libre Bruxelles, Serv Ecoethol Evolut, B-1050 Brussels, Belgium, Email: ohardy@ulb.ac.be
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 0962-1083 ISBN Medium
Area Expedition Conference
Notes (down) ISI:000235045500021 Approved no
Call Number EcoFoG @ eric.marcon @ Serial 183
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Author Ponton, S.; Flanagan, L.B.; Alstad, K.P.; Johnson, B.G.; Morgenstern, K.; Kljun, N.; Black, T.A.; Barr, A.G.
Title Comparison of ecosystem water-use efficiency among Douglas-fir forest, aspen forest and grassland using eddy covariance and carbon isotope techniques Type Journal Article
Year 2006 Publication Global Change Biology Abbreviated Journal Glob. Change Biol.
Volume 12 Issue 2 Pages 294-310
Keywords boreal forest; conifer forest; eddy covariance; grassland; stable isotopes
Abstract Comparisons were made among Douglas-fir forest, aspen (broad leaf deciduous) forest and wheatgrass (C-3) grassland for ecosystem-level water-use efficiency (WUE). WUE was defined as the ratio of photosynthetic CO2 assimilation rate and evapotranspiration (ET) rate. The ET data measured by eddy covariance were screened so that they overwhelmingly represented transpiration. The three sites used in this comparison spanned a range of vegetation (plant functional) types and environmental conditions within western Canada. When compared in the relative order Douglas-fir (located on Vancouver Island, BC), aspen (northern Saskatchewan), grassland (southern Alberta), the sites demonstrated a progressive decline in precipitation and a general increase in maximum air temperature and atmospheric saturation deficit (D-max) during the mid-summer. The average (+/- SD) WUE at the grassland site was 2.6 +/- 0.7 mmol mol(-1), which was much lower than the average values observed for the two other sites (aspen: 5.4 +/- 2.3, Douglas-fir: 8.1 +/- 2.4). The differences in WUE among sites were primarily because of variation in ET. The highest maximum ET rates were approximately 5, 3.2 and 2.7 mm day(-1) for the grassland, aspen and Douglas-fir sites, respectively. There was a strong negative correlation between WUE and D-max for all sites. We also made seasonal measurements of the carbon isotope ratio of ecosystem respired CO2 (delta(R)) in order to test for the expected correlation between shifts in environmental conditions and changes to the ecosystem-integrated ratio of leaf intercellular to ambient CO2 concentration (c(i)/c(a)). There was a consistent increase in delta(R) values in the grassland, aspen forest and Douglas-fir forest associated with a seasonal reduction in soil moisture. Comparisons were made between WUE measured using eddy covariance with that calculated based on D and delta(R) measurements. There was excellent agreement between WUE values calculated using the two techniques. Our delta(R) measurements indicated that c(i)/c(a) values were quite similar among the Douglas-fir, aspen and grassland sites, despite large variation in environmental conditions among sites. This implied that the shorter-lived grass species had relatively high c(i)/c(a) values for the D of their habitat. By contrast, the longer-lived Douglas-fir trees were more conservative in water-use with lower c(i)/c(a) values relative to their habitat D. This illustrates the interaction between biological and environmental characteristics influencing ecosystem-level WUE. The strong correlation we observed between the two independent measurements of WUE, indicates that the stable isotope composition of respired CO2 is a useful ecosystem-scale tool to help study constraints to photosynthesis and acclimation of ecosystems to environmental stress.
Address Univ Lethbridge, Dept Biol Sci, Lethbridge, AB T1K 3M4, Canada, Email: larry.flanagan@uleth.ca
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 1354-1013 ISBN Medium
Area Expedition Conference
Notes (down) ISI:000234974900013 Approved no
Call Number EcoFoG @ eric.marcon @ Serial 226
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Author Cochard, H.; Coste, S.; Chanson, B.; Guehl, J.M.; Nicolini, E.
Title Hydraulic architecture correlates with bud organogenesis and primary shoot growth in beech (Fagus sylvatica) Type Journal Article
Year 2005 Publication Tree Physiology Abbreviated Journal Tree Physiol.
Volume 25 Issue 12 Pages 1545-1552
Keywords development; hydraulic conductance; leaf primordia; meristem; xylem
Abstract In beech (Fagus sylvatica L.), the number of leaf primordia preformed in the buds determines the length and the type (long versus short) of annual growth units, and thus, branch growth and architecture. We analyzed the correlation between the number of leaf primordia and the hydraulic conductance of the vascular system connected to the buds. Terminal buds of short growth units and axillary buds of long growth units on lower branches of mature trees were examined. Buds with less than four and more than five leaf primordia formed short and long growth units, respectively. Irrespective of the type of growth unit the bud was formed on, the occurrence of a large number of leaf primordia was associated with high xylem hydraulic conductance. Xylem conductance was correlated to the area of the outermost annual ring. These results suggest that organogenesis and primary growth in buds correlates with secondary growth of the growth units and thus with their hydraulic architecture. Possible causal relationships between the variables are discussed.
Address INRA UBP, UMR PIAF, F-63039 Clermont Ferrand, France, Email: cochard@clermont.inra.fr
Corporate Author Thesis
Publisher HERON PUBLISHING Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0829-318X ISBN Medium
Area Expedition Conference
Notes (down) ISI:000234019900008 Approved no
Call Number EcoFoG @ webmaster @ Serial 281
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Author Gourlet-Fleury, S.; Blanc, L.; Picard, N.; Sist, P.; Dick, J.; Nasi, R.; Swaine, M.D.; Forni, E.
Title Grouping species for predicting mixed tropical forest dynamics: looking for a strategy Type Journal Article
Year 2005 Publication Annals of Forest Science Abbreviated Journal Ann. For. Sci.
Volume 62 Issue 8 Pages 785-796
Keywords cross-comparisons; functional groups; modelling strategy; species classifications
Abstract The high species diversity of mixed tropical forests hinders the development of forest dynamic models. A solution commonly adopted is to cluster species in groups. There are various methods for grouping species that can be linked to three strategies (i) the ecological subjective strategy, (ii) the ecological data-driven strategy, and (iii) the dynamic process strategy. In the first two strategies a species will be assigned to a single group while in the latter strategy, a specific grouping is defined for each process of population dynamics ( typically based on recruitment, growth, mortality). Little congruency or convergence is observed in the literature between any two classifications of species. This may be explained by the independence between the sets of tree characters used to build species groups, or by the intra-specific variability of these characters. We therefore recommend the dynamic process strategy as the most convenient strategy for building groups of species.
Address Cirad Foret, F-34398 Montpellier, France, Email: sylvie.gourlet-fleury@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 (down) ISI:000233972500001 Approved no
Call Number EcoFoG @ eric.marcon @ Serial 228
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Author Baraloto, C.; Forget, P.M.; Goldberg, D.E.
Title Seed mass, seedling size and neotropical tree seedling establishment Type Journal Article
Year 2005 Publication Journal of Ecology Abbreviated Journal J. Ecol.
Volume 93 Issue 6 Pages 1156-1166
Keywords French Guiana; life-history trade-offs; microhabitat; path analysis; regeneration strategy; relative growth rate; seedling survival; shade tolerance
Abstract 1 We examined among- and within-species effects of seed mass for seedling establishment from seed to 5 years of age in a field experiment at Paracou, French Guiana. 2 Six seeds of each of eight species were weighed and planted into each of 120 plots (1 m(2)) throughout closed-canopy forest along 12 100-m transects in 1998. 3 We described the microhabitat of each planting site using principal components derived from measurements of light availability, soil moisture, carbon and nitrogen content, and soil phosphorus availability. Although both survival and relative growth rate (RGR) increased with increasing light availability, no other microhabitat variable significantly affected seedling performance. Nor did the magnitude of microhabitat effects on survival or RGR differ among species. 4 Larger-seeded species were more likely to survive from germination to 1 year as well as from 1 to 5 years of age. RGR for seedling height during the first year post-germination was not related to seed mass, but smaller-seeded species did grow slightly faster thereafter. Path analyses revealed that correlations between seed mass and performance were explained in part because larger seeds produced larger initial seedlings, which tended to survive better but grow more slowly. 5 We also analysed within-species effects of seed mass for the larger-seeded Eperua grandiflora and Vouacapoua americana (both Caesalpiniaceae). Larger seeds produced larger seedlings in both species, but larger seeds survived better only for Eperua. Larger seedlings grew more slowly in both species, but did not offset the early (Eperua) and later (Vouacapoua) positive direct effects of seed mass on RGR that may represent contrasting strategies for reserve deployment. 6 Our results demonstrate that seed size influences performance within and among species in part because of indirect effects of initial seedling size. However, we suggest that traits tightly correlated with seed mass at the species level, such as specific leaf area, leaf longevity and photosynthetic capacity, may also contribute to interspecific performance differences.
Address Museum Natl Hist Nat, Dept Ecol & Gest Biodivers, UMR 5176, CNRS, Brunoy, France, Email: baraloto.c@kourou.cirad.fr
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 0022-0477 ISBN Medium
Area Expedition Conference
Notes (down) ISI:000233287500012 Approved no
Call Number EcoFoG @ eric.marcon @ Serial 250
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Author Liu, S.Q.; Loup, C.; Gril, J.; Dumonceaud, O.; Thibaut, A.; Thibaut, B.
Title Studies on European beech (Fagus sylvatica L.). Part 1: Variations of wood colour parameters Type Journal Article
Year 2005 Publication Annals of Forest Science Abbreviated Journal Ann. For. Sci.
Volume 62 Issue 7 Pages 625-632
Keywords Fagus sylvatica L.; CIELab colour system; solid wood; red heartwood
Abstract Colour parameters of European beech were measured using CIELab system. 103 logs from 87 trees in 9 sites were cut into boards to study the radial variations of wood colour parameters. Both site and tree effects on colour were observed. Patterns of red heartwood occurrence were defined. When excepting red heartwood there was still a highly significant effect of site and tree. Axial and radial variations were small, except very near the pith or in red heartwood, suggesting possible early selection at periphery under colour criteria. Red heartwood is darker, redder and more yellow than normal peripheral wood.
Address Univ Montpellier 2, Lab Mecan & Genie Civil, F-34095 Montpellier, France, Email: jgril@lmgc.univ-montp2.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 (down) ISI:000233179100003 Approved no
Call Number EcoFoG @ eric.marcon @ Serial 251
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Author Roggy, J.C.; Nicolini, E.; Imbert, P.; Caraglio, Y.; Bosc, A.; Heuret, P.
Title Links between tree structure and functional leaf traits in the tropical forest tree Dicorynia guianensis Amshoff (Caesalpiniaceae) Type Journal Article
Year 2005 Publication Annals of Forest Science Abbreviated Journal Ann. For. Sci.
Volume 62 Issue 6 Pages 553-564
Keywords Dicorynia guianensis; leaf structure; functional leaf traits; plasticity; tree structure
Abstract This study looked at the interactive effects of tree architectural stage of development (ASD) and light availability on different plant traits (growth parameters, leaf morpho-anatomy and photosynthetic capacities) in the tropical species Dicorynia guianensis. A qualitative architectural analysis was used to categorize tree individuals sampled along a natural light gradient. The results show that some traits could have an ASD-dependence at the whole plant and leaf level without control of light. The changes observed relate to vigour thresholds the plant has to reach to shift from one ASD to another (i.e., the number of nodes and the internodes length per Growth Unit). Light conditions do not modify these thresholds but may modify the time they are crossed. Tree height was found strongly modulated by light conditions; hence, at a similar height, individuals may belong to different ASD. At the functional level, a decrease in N-m, and A(maxm) was observed with increasing light availability, while N-a increased and A(maxa) remained unaffected. An ASD effect was also observed on Amaxa and LMA but not on Amaxm. These results demonstrated a weak ability of photosynthetic plasticity in response to light conditions, and that variations of leaf photosynthetic variables according to ASD can be explained by modifications in leaf nitrogen and LMA. Questions on the reliability of a height-based sampling strategy for evaluating the phenotypic plasticity of trees in relation to light conditions are raised.
Address INRA, Ecol Forets Guyane, ENGREF, UMR CIRAD, F-97387 Kourou, Guyane Francais, France, Email: roggy.j@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 (down) ISI:000232084400009 Approved no
Call Number EcoFoG @ eric.marcon @ Serial 229
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Author Picard, N.; Gourlet-Fleury, S.; Sist, P.
Title Using process-dependent groups of species to model the dynamics of a tropical rainforest Type Journal Article
Year 2003 Publication Modelling Forest Systems Abbreviated Journal
Volume Issue Pages 237-248
Keywords
Abstract The high tree species diversity in tropical forests is difficult to take into account in models. The usual solution consists of defining groups of species and then adjusting a set of parameters for each group. In this study, we address this issue by allowing a species to move from one species group to another, depending on the biological process that is concerned. We developed this approach with a matrix model of forest dynamics, for a tropical rainforest in French Guiana, at Paracou, focusing on the methodological aspects. The forest dynamics is split into three components: recruitment, growth and mortality. We then built five recruitment groups, five growth groups and five mortality groups. One species is characterized by a combination of the three groups, thus yielding in total 5 X 5 X 5 = 125 possibilities, out of which 43 are actually observed. The resulting matrix model provides a better view of the floristic composition of the forest, and does not have more parameters than it would have with five global species groups. However, its predictions are no more precise than those of the matrix model based on five global groups.
Address Cirad Foret, Montpellier, France
Corporate Author Thesis
Publisher CABI PUBLISHING 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 (down) ISI:000231866400021 Approved no
Call Number EcoFoG @ eric.marcon @ Serial 249
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Author Coste, S.; Roggy, J.C.; Imbert, P.; Born, C.; Bonal, D.; Dreyer, E.
Title Leaf photosynthetic traits of 14 tropical rain forest species in relation to leaf nitrogen concentration and shade tolerance Type Journal Article
Year 2005 Publication Tree Physiology Abbreviated Journal Tree Physiol.
Volume 25 Issue 9 Pages 1127-1137
Keywords functional diversity; leaf carbon; leaf nitrogen; nitrogen-use efficiency; photosynthetic capacity; tropical rain forest
Abstract Variability of leaf traits related to photosynthesis was assessed in seedlings from 14 tree species growing in the tropical rain forest of French Guiana. Leaf photosynthetic capacity (maximum rate of carboxylation and maximum rate of electron transport) was estimated by fitting a biochemical model of photosynthesis to response curves of net CO2 assimilation rate versus intercellular CO2 mole fraction. Leaf morphology described by leaf mass per unit leaf area (LMA), density and thickness, as well as area- and mass-based nitrogen (N) and carbon (C) concentrations, were recorded on the same leaves. Large interspecific variability was detected in photosynthetic capacity as well as in leaf structure and leaf N and C concentrations. No correlation was found between leaf thickness and density. The correlations between area- and mass-based leaf N concentration and photosynthetic capacity were poor. Conversely, the species differed greatly in relative N allocation to carboxylation and bioenergetics. Principal component analysis (PCA) revealed that, of the recorded traits, only the computed fraction of total leaf N invested in photosynthesis was tightly correlated to photosynthetic capacity. We also used PCA to test to what extent species with similar shade tolerances displayed converging leaf traits related to photosynthesis. No clear-cut ranking could be detected among the shade-tolerant groups, as confirmed by a one-way ANOVA. We conclude that the large interspecific diversity in photosynthetic capacity was mostly explained by differences in the relative allocation of N to photosynthesis and not by leaf N concentration, and that leaf traits related to photosynthetic capacity did not discriminate shade-tolerance ranking of these tropical tree species.
Address CNRS Ecol Forets Guyane, INRA, ENGREF,CIRAD, Unite Mixte Rech, Kourou 97387, French Guiana, Email: roggy.j@cirad.fr
Corporate Author Thesis
Publisher HERON PUBLISHING Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0829-318X ISBN Medium
Area Expedition Conference
Notes (down) ISI:000231555200005 Approved no
Call Number EcoFoG @ eric.marcon @ Serial 230
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