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Author Baraloto, C.; Goldberg, D.E.
Title Microhabitat associations and seedling bank dynamics in a neotropical forest Type Journal Article
Year 2004 Publication Oecologia Abbreviated Journal Oecologia
Volume 141 Issue 4 Pages 701-712
Keywords French Guiana; life history traits; light availability; regeneration niche; soil nutrients
Abstract We conducted a rigorous test of tropical tree seedling microhabitat differentiation by examining microhabitat associations, survival and growth of established seedlings of ten tropical tree species representing a four-factor gradient in seed size. Eight microhabitat variables describing soil and light conditions were measured directly adjacent to each of 588 seedlings within twelve 10 x 100 m belt transects at Paracou, French Guiana, and at 264 reference points along the transects. From these measurements, we defined three principal components describing soil richness, soil softness and canopy openness. Six of ten species ( in 9 of 30 total cases) were distributed non-randomly with respect to microhabitat along at least one principal component. However, few species demonstrated clear microhabitat specialization. All shifts in distribution relative to reference points were in the same direction ( richer, softer soil). Furthermore, of 135 pairwise comparisons among the species, only 7 were significantly different. More than three-fourths of all seedlings (75.3%) survived over the 2-year monitoring period, but survival rates varied widely among species. In no case was the probability of survival influenced by any microhabitat parameter. Relative height growth rates for the seedlings over 2 years varied from – 0.031 cm cm(-1) year(-1) (Dicorynia guianensis, Caesalpiniaceae) to 0.088 cm cm(-1) year(-1) (Virola michelii, Myristicaceae). In only 4 of 30 cases was height growth significantly associated with one of the three principal components. Because the conditions in this study were designed to maximize the chance of finding microhabitat differentiation among a group of species differing greatly in life history traits, the lack of microhabitat specialization it uncovered suggests that microhabitat partitioning among tropical tree species at the established seedling stage is unlikely to contribute greatly to coexistence among these species.
Address INRA Kourou, UMR Ecol Forets Guyane, Kourou 97387, French Guiana, Email: baraloto.c@kourou.cirad.fr
Corporate Author Thesis
Publisher (down) SPRINGER Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0029-8549 ISBN Medium
Area Expedition Conference
Notes ISI:000224999800015 Approved no
Call Number EcoFoG @ eric.marcon @ Serial 233
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Author Almeras, T.; Thibaut, A.; Gril, J.
Title Effect of circumferential heterogeneity of wood maturation strain, modulus of elasticity and radial growth on the regulation of stem orientation in trees Type Journal Article
Year 2005 Publication Trees-Structure and Function Abbreviated Journal Trees-Struct. Funct.
Volume 19 Issue 4 Pages 457-467
Keywords biomechanics; reaction wood; maturation strain; Young's modulus; eccentricity
Abstract Active mechanisms of re-orientation are necessary to maintain the verticality of tree stems. They are achieved through the production of reaction wood, associated with circumferential variations of three factors related to cambial activity: maturation strain, longitudinal modulus of elasticity (MOE) and eccentric growth. These factors were measured on 17 mature trees from different botanical families and geographical locations. Various patterns of circumferential variation of these factors were identified. A biomechanical analysis based on beam theory was performed to quantify the individual impact of each factor. The main factor of re-orientation is the circumferential variation of maturation strains. However, this factor alone explains only 57% of the re-orientations. Other factors also have an effect through their interaction with maturation strains. Eccentric growth is generally associated with heterogeneity of maturation strains, and has an important complementary role, by increasing the width of wood with high maturation strain. Without this factor, the efficiency of re-orientations would be reduced by 31% for angiosperms and 26% for gymnosperms. In the case of angiosperms, MOE is often larger in tension wood than in normal wood. Without these variations, the efficiency of re-orientations would be reduced by 13%. In the case of gymnosperm trees, MOE of compression wood is lower than that of normal wood, so that re-orientation efficiency would be increased by 24% without this factor of variations.
Address Nagoya Univ, Lab Biomat Phys, Dept Bioagr Sci, Nagoya, Aichi 4648601, Japan, Email: t_almeras@hotmail.com
Corporate Author Thesis
Publisher (down) 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:000229890700012 Approved no
Call Number EcoFoG @ eric.marcon @ Serial 253
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Author Scotti-Saintagne, C.; Bodenes, C.; Barreneche, T.; Bertocchi, E.; Plomion, C.; Kremer, A.
Title Detection of quantitative trait loci controlling bud burst and height growth in Quercus robur L Type Journal Article
Year 2004 Publication Theoretical and Applied Genetics Abbreviated Journal Theor. Appl. Genet.
Volume 109 Issue 8 Pages 1648-1659
Keywords
Abstract Genetic variation of bud burst and early growth components was estimated in a full-sib family of Quercus robur L. comprising 278 offspring. The full sibs were vegetatively propagated, and phenotypic assessments were made in three field tests. This two-generation pedigree was also used to construct a genetic linkage map (12 linkage groups, 128 markers) and locate quantitative trait loci (QTLs) controlling bud burst and growth components. In each field test, the date of bud burst extended over a period of 20 days from the earliest to the latest clone. Bud burst exhibited higher heritability (0.15-0.51) than growth components (0.04-0.23) and also higher correlations across field tests. Over the three tests there were 32 independent detected QTLs (Pless than or equal to5% at the chromosome level) controlling bud burst, which likely represent at least 12 unique genes or chromosomal regions controlling this trait. QTLs explained from 3% to 11% of the variance of the clonal means. The number of QTLs controlling height growth components was lower and varied between two and four. However the contribution of each QTL to the variance of the clonal mean was higher (from 4% to 19%). These results indicate that the genetic architecture of two important fitness-related traits are quite different. On the one hand, bud burst is controlled by several QTLs with rather low to moderate effects, but contributing to a high genetic (additive) variance. On the other hand, height growth depends on fewer QTLs with moderate to strong effects, resulting in lower heritabilities of the trait.
Address INRA, UMR Biodivers Genes & Ecosyst, F-33612 Cestas, France, Email: antoine.kremer@pierroton.inra.fr
Corporate Author Thesis
Publisher (down) SPRINGER Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0040-5752 ISBN Medium
Area Expedition Conference
Notes ISI:000225054800012 Approved no
Call Number EcoFoG @ eric.marcon @ Serial 260
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Author Sobotnik, J.; Sillam-Dusses, D.; Weyda, F.; Dejean, A.; Roisin, Y.; Hanus, R.; Bourguignon, T.
Title The frontal gland in workers of Neotropical soldierless termites Type Journal Article
Year 2010 Publication Naturwissenschaften Abbreviated Journal Naturwissenschaften
Volume 97 Issue 5 Pages 495-503
Keywords Frontal gland; Workers; Soldierless termites; Apicotermitinae; Anoplotermes; Aparatermes
Abstract The presence of the frontal gland is well established in termite soldiers of Rhinotermitidae, Serritermitidae, and Termitidae. It is one of their main defensive adaptations or even an exclusive weapon. The gland was also occasionally reported in alate imagoes, but never in the worker caste. Here, we report the first observation of a frontal gland in workers of several Neotropical and one African species of Apicotermitinae. The ultrastructure of Aparatermes cingulatus and Anoplotermes nr. subterraneus is described in detail. In these two species, the gland is well-developed, functional and consists of class 1 secretory cells. The presence of envelope cells, wrapping the gland, is an unusual feature, as well as the presence of several zonulae adherens, connecting neighbouring glandular cells. The frontal gland of workers is homologous to this organ in soldiers and imagoes, as evidenced by the same position in the head and its connection to the same muscle. However, the defensive role of the frontal gland in workers remains to be confirmed.
Address [Sobotnik, Jan; Sillam-Dusses, David; Hanus, Robert] Acad Sci Czech Republic, Inst Organ Chem & Biochem, Res Team Infochem, CR-16610 Prague 6, Czech Republic, Email: robert@uochb.cas.cz
Corporate Author Thesis
Publisher (down) SPRINGER Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0028-1042 ISBN Medium
Area Expedition Conference
Notes ISI:000277318800007 Approved no
Call Number EcoFoG @ webmaster @ Serial 285
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Author Wernsdorfer, H.; Caron, H.; Gerber, S.; Cornu, G.; Rossi, V.; Mortier, F.; Gourlet-Fleury, S.
Title Relationships between demography and gene flow and their importance for the conservation of tree populations in tropical forests under selective felling regimes Type Journal Article
Year 2011 Publication Conservation Genetics Abbreviated Journal Conserv. Genet.
Volume 12 Issue 1 Pages 15-29
Keywords Genetic diversity; Gene flow; Population dynamics; Simulation model; Conservation; Forest management
Abstract Determining how tropical tree populations subject to selective felling (logging) pressure may be conserved is a crucial issue for forest management and studying this issue requires a comprehensive understanding of the relationships between population demography and gene flow. We used a simulation model, SELVA, to study (1) the relative impact of demographic factors (juvenile mortality, felling regime) and genetic factors (selfing, number and location of fathers, mating success) on long-term genetic diversity; and (2) the impact of different felling regimes on population size versus genetic diversity. Impact was measured by means of model sensitivity analyses. Juvenile mortality had the highest impact on the number of alleles and genotypes, and on the genetic distance between the original and final populations. Selfing had the greatest impact on observed heterozygote frequency and fixation index. Other factors and interactions had only minor effects. Overall, felling had a greater impact on population size than on genetic diversity. Interestingly, populations under relatively low felling pressure even had a somewhat lower fixation index than undisturbed populations (no felling). We conclude that demographic processes such as juvenile mortality should be modelled thoroughly to obtain reliable long-term predictions of genetic diversity. Mortality in selfed and outcrossed progenies should be modelled explicitly by taking inbreeding depression into account. The modelling of selfing based on population rate appeared to be oversimplifying and should account for inter-tree variation. Forest management should pay particular attention to the regeneration capacities of felled species.
Address [Wernsdoerfer, Holger] Ctr INRA Nancy, INRA, Lab Etude Ressources Foret Bois LERFoB, UMR1092, F-54280 Champenoux, France, Email: holger.wernsdoerfer@cirad.fr
Corporate Author Thesis
Publisher (down) SPRINGER Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1566-0621 ISBN Medium
Area Expedition Conference
Notes ISI:000285971900002 Approved no
Call Number EcoFoG @ eric.marcon @ Serial 289
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Author Orivel, J.; Lambs, L.; Male, P.J.G.; Leroy, C.; Grangier, J.; Otto, T.; Quilichini, A.; Dejean, A.
Title Dynamics of the association between a long-lived understory myrmecophyte and its specific associated ants Type Journal Article
Year 2011 Publication Oecologia Abbreviated Journal Oecologia
Volume 165 Issue 2 Pages 369-376
Keywords Allomerus decemarticulatus; Hirtella physophora; Lifespan; Mutualism; Myrmecophyte
Abstract Myrmecophytic symbioses are widespread in tropical ecosystems and their diversity makes them useful tools for understanding the origin and evolution of mutualisms. Obligate ant-plants, or myrmecophytes, provide a nesting place, and, often, food to a limited number of plant-ant species. In exchange, plant-ants protect their host plants from herbivores, competitors and pathogens, and can provide them with nutrients. Although most studies to date have highlighted a similar global pattern of interactions in these systems, little is known about the temporal structuring and dynamics of most of these associations. In this study we focused on the association between the understory myrmecophyte Hirtella physophora (Chrysobalanaceae) and its obligate ant partner Allomerus decemarticulatus (Myrmicinae). An examination of the life histories and growth rates of both partners demonstrated that this plant species has a much longer lifespan (up to about 350 years) than its associated ant colonies (up to about 21 years). The size of the ant colonies and their reproductive success were strongly limited by the available nesting space provided by the host plants. Moreover, the resident ants positively affected the vegetative growth of their host plant, but had a negative effect on its reproduction by reducing the number of flowers and fruits by more than 50%. Altogether our results are important to understanding the evolutionary dynamics of ant-plant symbioses. The highly specialized interaction between long-lived plants and ants with a shorter lifespan produces an asymmetry in the evolutionary rates of the interaction which, in return, can affect the degree to which the interests of the two partners converge.
Address [Orivel, Jerome; Leroy, Celine; Quilichini, Angelique; Dejean, Alain] CNRS, UMR Ecol Forets Guyane, F-97379 Kourou, France, Email: jerome.orivel@ecofog.gf
Corporate Author Thesis
Publisher (down) Springer Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0029-8549 ISBN Medium
Area Expedition Conference
Notes ISI:000286224900012 Approved no
Call Number EcoFoG @ webmaster @ Serial 295
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Author Ruelle, J.; Beauchene, J.; Yamamoto, H.; Thibaut, B.
Title Variations in physical and mechanical properties between tension and opposite wood from three tropical rainforest species Type Journal Article
Year 2011 Publication Wood Science and Technology Abbreviated Journal Wood Sci. Technol.
Volume 45 Issue 2 Pages 339-357
Keywords
Abstract Growth strains were measured in situ in nine trees of three species from a French Guiana tropical rainforest in a clearly active verticality restoration process. The aim was to detect tension wood within the samples. Wood specimens were cut in the vicinity of the growth strain measurements in order to determine the microfibril angle and some mechanical and physical properties. As suspected, tensile growth strain was much higher in tension wood zones, as shown by the slightly higher longitudinal modulus of elasticity. Conversely, tension wood showed reduced compression strength. Longitudinal shrinkage was much higher in tension wood than in opposite wood. Clear relationships between the microfibril angle and longitudinal properties were noted in comparison (i) with those observed in gymnosperm compression wood and (ii) with expected relationships from the organization of wood fibres cell wall structure.
Address [Ruelle, Julien; Yamamoto, Hiroyuki] Nagoya Univ, Grad Sch Bioagr Sci, Nagoya, Aichi 4648601, Japan, Email: julien.ruelle@ecofog.gf
Corporate Author Thesis
Publisher (down) 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:000289477300013 Approved no
Call Number EcoFoG @ webmaster @ Serial 305
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Author Coq, S.; Weigel, J.; Butenschoen, O.; Bonal, D.; Hattenschwiler, S.
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 [Coq, Sylvain; Haettenschwiler, Stephan] CNRS, CEFE, F-34293 Montpellier 5, France, Email: sylvain.coq@gmail.com
Corporate Author Thesis
Publisher (down) 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 Bremaud, I.; Amusant, N.; Minato, K.; Gril, J.; Thibaut, B.
Title Effect of extractives on vibrational properties of African Padauk (Pterocarpus soyauxii Taub.) Type Journal Article
Year 2011 Publication Wood Science and Technology Abbreviated Journal Wood Sci. Technol.
Volume 45 Issue 3 Pages 461-472
Keywords
Abstract Extractives can affect the vibrational properties tan delta (damping coefficient) and E'/rho (specific Young's modulus), but this is highly dependent on species, compounds, and cellular locations. This paper investigates such effects for African Padauk (Pterocarpus soyauxii Taub.), a tropical hardwood with high extractives content and a preferred material for xylophones. Five groups of 26 heartwood specimens with large, yet comparable, ranges in vibrational properties were extracted in different solvents. Changes in vibrational properties were set against yields of extracts and evaluation of their cellular location. Methanol (ME) reached most of the compounds (13%), located about half in lumen and half in cell-wall. Water solubility was extremely low. tan delta and E'/rho were very strongly related (R (2) a parts per thousand yen 0.93), but native wood had abnormally low values of tan delta, while extraction shifted this relation towards higher tan delta values. ME extracted heartwood became in agreement with the average of many species, and close to sapwood. Extractions increased tan delta as much as 60%, irrespective of minute moisture changes or initial properties. Apparent E'/rho was barely changed (+2% to -4%) but, after correcting the mass contribution of extracts, it was in fact slightly reduced (down to -10% for high E'/rho), and increasingly so for specimens with low initial values of E'/rho.
Address [Bremaud, I; Minato, K] Kyoto Prefectural Univ, Lab Forest Resource Circulating Circles, Grad Sch Life & Environm Sci, Kyoto 6068522, Japan, Email: iris_bremaud@hotmail.com
Corporate Author Thesis
Publisher (down) 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 WOS:000292550700005 Approved no
Call Number EcoFoG @ webmaster @ Serial 329
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Author Barantal, S.; Roy, J.; Fromin, N.; Schimann, H.; Hattenschwiler, S.
Title Long-term presence of tree species but not chemical diversity affect litter mixture effects on decomposition in a neotropical rainforest Type Journal Article
Year 2011 Publication Oecologia Abbreviated Journal Oecologia
Volume 167 Issue 1 Pages 241-252
Keywords Amazonian rainforest; Chemical diversity; Decomposition; Functional diversity indices; Litter traits
Abstract Plant litter diversity effects on decomposition rates are frequently reported, but with a strong bias towards temperate ecosystems. Altered decomposition and nutrient recycling with changing litter diversity may be particularly important in tree species-rich tropical rainforests on nutrient-poor soils. Using 28 different mixtures of leaf litter from 16 Amazonian rainforest tree species, we tested the hypothesis that litter mixture effects on decomposition increase with increasing functional litter diversity. Litter mixtures and all single litter species were exposed in the field for 9 months using custom-made microcosms with soil fauna access. In order to test the hypothesis that the long-term presence of tree species contributing to the litter mixtures increases mixture effects on decomposition, microcosms were installed in a plantation at sites including the respective tree species composition and in a nearby natural forest where these tree species are absent. We found that mixture decomposition deviated from predictions based on single species, with predominantly synergistic effects. Functional litter diversity, defined as either richness, evenness, or divergence based on a wide range of chemical traits, did not explain the observed litter mixture effects. However, synergistic effects in litter mixtures increased with the long-term presence of tree species contributing to these mixtures as the home field advantage hypothesis assumes. Our data suggest that complementarity effects on mixed litter decomposition may emerge through long-term interactions between aboveground and belowground biota.
Address [Barantal, S; Roy, J; Fromin, N; Hattenschwiler, S] CEFE CNRS, UMR 5175, F-34293 Montpellier 5, France, Email: sandra.barantal@cefe.cnrs.fr
Corporate Author Thesis
Publisher (down) Springer Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0029-8549 ISBN Medium
Area Expedition Conference
Notes WOS:000293914000024 Approved no
Call Number EcoFoG @ webmaster @ Serial 336
Permanent link to this record