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Author Delaval, M.; Henry, M.; Charles-Dominique, P. openurl 
  Title Interspecific competition and niche partitioning: Example of a neotropical rainforest bat community Type Journal Article
  Year 2005 Publication Revue d'Ecologie (La Terre et la Vie) Abbreviated Journal Rev. Ecol.-Terre Vie  
  Volume 60 Issue 2 Pages 149-165  
  Keywords  
  Abstract To understand the organization of a bat community and the coexistence of sympatric species, it is essential to understand how species use and share common resources. First, we describe a bat community in a primary rainforest of French Guiana. The presence of particular roosting sites, such as caves, and the absence of disturbances are important local factors in structuring communities. In the course of this study, we focused on the three most common species of three vegetarian bat guilds (understorey frugivores, canopy frugivores and nectarivores). The local coexistence of these species is possible thanks to space, food and/or time partitioning. Space partitioning is consistent with the hypothesis that smaller bats with a more manoeuvrable flight tend to occupy more cluttered space less attractive to their competitors and have smaller home range. We observed a time partitioning that is likely to reduce competition among some frugivorous bat species by reducing direct interference during foraging. Besides an interest for the field community ecology, this study of a community living in a primary forest can be used as a reference for non disturbed habitat for conservation purposes.  
  Address Dept Ecol & Gestion Biodivers, UMR 5176, F-91800 Brunoy, France, Email: marguerite.delaval@wanadoo.fr  
  Corporate Author Thesis  
  Publisher SOC NATL PROTECTION NATURE ACCLIMATATION FRANCE Place of Publication Editor  
  Language (down) Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0249-7395 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000230973300005 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 231  
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Author Bereau, M.; Bonal, D.; Louisanna, E.; Garbaye, J. openurl 
  Title Do mycorrhizas improve tropical tree seedling performance under water stress and low light conditions? A case study with Dicorynia guianensis (Caesalpiniaceae) Type Journal Article
  Year 2005 Publication Journal of Tropical Ecology Abbreviated Journal J. Trop. Ecol.  
  Volume 21 Issue Pages 375-381  
  Keywords French Guiana; leaf gas exchange; mycorrhizal symbiosis; tropical forest; water limitation  
  Abstract We tested the response of seedlings of Diconyina guianensis, a major timber tree species of French Guiana, to mycorrhizal symbiosis and water limitation in a semi-con trolled experiment under natural light conditions. Under well-watered conditions, mycorrhizal colonization resulted in an increase of net photosynthesis, growth and phosphorus uptake. When submitted to water stress, no growth reduction of mycorrhizal seedlings was observed. Mycorrhizal seedlings were more sensitive to drought than non-mycorrhizal ones in terms of carbon assimilation, but not with regard to stomatal closure. In contrast to previous studies on temperate tree seedlings, this result precludes a mycorrhizal effect on the hydraulic properties of this species. Furthermore, our results suggest that below a specific threshold of soil moisture, carbon assimilation of D. guianensis seedlings was decreased by the mycorrhizal symbiosis. This is probably related to the competition between the plant and its host fungus for carbon allocation under low light intensity, even though it did not seem to have a significant effect on mortality in our experiment.  
  Address UMR Ecofog, Kourou 97387, French Guiana, Email: bercau.m@kourou.cirad.fr  
  Corporate Author Thesis  
  Publisher CAMBRIDGE UNIV PRESS Place of Publication Editor  
  Language (down) Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0266-4674 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000231009300003 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 232  
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Author Baraloto, C.; Goldberg, D.E. openurl 
  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 SPRINGER Place of Publication Editor  
  Language (down) 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 Phillips, P.D.; Thompson, I.S.; Silva, J.N.M.; van Gardingen, P.R.; Degen, B. openurl 
  Title Scaling up models of tree competition for tropical forest population genetics simulation Type Journal Article
  Year 2004 Publication Ecological Modelling Abbreviated Journal Ecol. Model.  
  Volume 180 Issue 2-3 Pages 419-434  
  Keywords tropical rain; forest; population genetics; model SYMFOR; eco-gene; scaling up; competition  
  Abstract Understanding the effects of logging activity on genetic diversity is an important aspect of establishing the sustainability of selective logging management operations in tropical forests. Genetic variation is affected by selective logging directly, through the removal of and damage to trees within the population, and indirectly, through a change in the forest structure and environment in which the remaining population lives. Eco-Gene is a population genetics model applied to tropical forests over a scale of hundreds of hectares. SYMFOR is a modelling framework for individual-based spatially explicit ecological and management models applied to tropical forests over a scale of 0.25 4 ha. We have linked the models to enable simulations using processes involved in both models. To overcome problems of scale, the spatially explicit competition index calculated in SYMFOR simulations has been modelled such that it can be applied at scales representing much larger areas for which the data are not available, as required by Eco-Gene. The competition index is modelled as a distribution on a grid-square basis, and implemented in the linked Eco-Gene/SYMFOR system. Each tree within a grid-square is given a “relative competition” within the distribution, biased according to species. A competition index value is obtained for the tree by transforming the grid-square distribution to be relevant to the size of the tree, and extracting a value according to the tree's relative competition within the distribution. The distribution and each tree's relative competition within it change according to the effects of growth, mortality and logging activity. The model was calibrated using data from the Tapajos region of the Eastern Amazon forest. This paper describes the model, its calibration and validation and the implications of scaling up from an explicit representation to a modelled quantity. (C) 2004 Elsevier B.V. All rights reserved.  
  Address Embrapa Amazonia Oriental, BR-66095100 Belem, Para, Brazil, Email: paul.phillips@envams.co.uk  
  Corporate Author Thesis  
  Publisher ELSEVIER SCIENCE BV Place of Publication Editor  
  Language (down) Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0304-3800 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000224635700012 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 234  
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Author Eva, H.D.; Belward, A.S.; De Miranda, E.E.; Di Bella, C.M.; Gond, V.; Huber, O.; Jones, S.; Sgrenzaroli, M.; Fritz, S. openurl 
  Title A land cover map of South America Type Journal Article
  Year 2004 Publication Global Change Biology Abbreviated Journal Glob. Change Biol.  
  Volume 10 Issue 5 Pages 731-744  
  Keywords Amazonia; ecosystems; land cover; mapping; South America; vegetation classes  
  Abstract A digital land cover map of South America has been produced using remotely sensed satellite data acquired between 1995 and the year 2000. The mapping scale is defined by the 1 km spatial resolution of the map grid-cell. In order to realize the product, different sources of satellite data were used, each source providing either a particular parameter of land cover characteristic required by the legend, or mapping a particular land cover class. The map legend is designed both to fit requirements for regional climate modelling and for studies on land cover change. The legend is also compatible with a wider, global, land cover mapping exercise, which seeks to characterize the world's land surface for the year 2000. As a first step, the humid forest domain has been validated using a sample of high-resolution satellite images. The map demonstrates both the major incursions of agriculture into the remaining forest domains and the extensive areas of agriculture, which now dominate South America's grasslands.  
  Address Commiss European Communities, Joint Res Ctr, Inst Environm & Sustainabil, TP 440, I-21020 Ispra, Italy, Email: hugh.eva@jrc.it  
  Corporate Author Thesis  
  Publisher BLACKWELL PUBLISHING LTD Place of Publication Editor  
  Language (down) 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 ISI:000221421600015 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 235  
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Author Roggy, J.C.; Moiroud, A.; Lensi, R.; Domenach, A.M. openurl 
  Title Estimating N transfers between N-2-fixing actinorhizal species and the non-N-2-fixing Prunus avium under partially controlled conditions Type Journal Article
  Year 2004 Publication Biology and Fertility of Soils Abbreviated Journal Biol. Fertil. Soils  
  Volume 39 Issue 5 Pages 312-319  
  Keywords actinorhizal trees; mixed culture; litter; N transfer by roots; N-15  
  Abstract Two methods of N transfer between plants-by litter decomposition and root-to-root exchange-were examined in mixed plantations of N-fixing and non-fixing trees. Nitrogen transfers from decaying litters were measured by placing N-15-labelled litters from four actinorhizal tree species around shoots of containerized Prunus avium. Nitrogen transfers by root-to-root exchanges were measured after foliar NO3-N-15 fertilization of Alnus subcordata and Elaeagnus angustifolia growing in containers in association with P. avium. During the first 2 years of litter decomposition, from 5-20% of the N, depending on the litter identity, was released and taken up by P. avium. N availability in the different litters was strongly correlated with the amount of water-soluble N, which was highest in leaves of E. angustifolia. In the association between fixing and non-fixing plants, 7.5% of the A. subcordata N and 25% of E. angustifolia N was transferred to P. avium by root exchange. These results showed that the magnitude of N transfers by root exchange depended on the associated N-2-fixing species. Among the species investigated, E. angustifolia displayed the highest capacity for exudating N from roots as well as for releasing N from litters. These qualities make this tree a promising species for enhancing wood yields in mixed stands.  
  Address INRA, ENGREF, CIRAD, Unite Mixte Rech,Lab Ecol Forets Trop Guyane, Kourou 97387, French Guiana, Email: roggy.j@cirad.fr  
  Corporate Author Thesis  
  Publisher SPRINGER-VERLAG Place of Publication Editor  
  Language (down) Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0178-2762 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000221197000002 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 236  
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Author Latouche-Halle, C.; Ramboer, A.; Bandou, E.; Caron, H.; Kremer, A. openurl 
  Title Long-distance pollen flow and tolerance to selfing in a neotropical tree species Type Journal Article
  Year 2004 Publication Molecular Ecology Abbreviated Journal Mol. Ecol.  
  Volume 13 Issue 5 Pages 1055-1064  
  Keywords Dicorynia guianensis; microsatellites; outcrossing rate; pollen flow; reproductive success; tropical tree  
  Abstract Outcrossing rates, pollen dispersal and male mating success were assessed in Dicorynia guianensis Amshoff, a neotropical tree endemic to the Guiana shield. All adult trees within a continuous area of 40 ha (n = 157) were mapped, and were genotyped with six microsatellite loci. In addition, progenies were genotyped from 22 mature trees. At the population level, the species was mostly outcrossing (t(m) = 0.89) but there was marked variation among individuals. One tree exhibited mixed mating, confirming earlier results obtained with isozymes that D. guianensis can tolerate selfing. A Bayesian extension of the fractional paternity method was used for paternity analysis, and was compared with the neighbourhood method used widely for forest trees. Both methods indicated that pollen dispersal was only weakly related to distance between trees within the study area, and that the majority (62%) of pollen came from outside the study stand. Using maximum likelihood, male potential population size was estimated to be 1119, corresponding to a neighbourhood size of 560 hectares. Male mating success was, however, related to the diameter of the stem and to flowering intensity assessed visually. The mating behaviour of D. guianensis is a combination of long-distance pollen flow and occasional selfing. The species can still reproduce when it is extremely rare, either by selfing or by dispersing pollen at long distances. These results, together with the observation that male mating success was correlated with the size of the trees, could be implemented in management procedures aiming at regenerating the species.  
  Address INRA, UMR Ecol Forets Guyane, F-97387 Kourou, France, Email: caron@pierroton.mra.fr  
  Corporate Author Thesis  
  Publisher BLACKWELL PUBLISHING LTD Place of Publication Editor  
  Language (down) 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 ISI:000221016300007 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 237  
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Author Phillips, P.D.; de Azevedo, C.P.; Degen, B.; Thompson, I.S.; Silva, J.N.M.; van Gardingen, P.R. openurl 
  Title An individual-based spatially explicit simulation model for strategic forest management planning in the eastern Amazon Type Journal Article
  Year 2004 Publication Ecological Modelling Abbreviated Journal Ecol. Model.  
  Volume 173 Issue 4 Pages 335-354  
  Keywords model; individual; tropical forest; tree; spatial; Brazil; Amazon; competition; species grouping; management; certification; regulation  
  Abstract A model to simulate the ecological processes of tree growth, mortality and recruitment, and the processes of forest management, in the terra firme forests of the eastern Amazon is described. It is implemented within the SYMFOR (http://www.symfor.org) framework. It is based on measurements of all trees that have a diameter greater than 5 cm from experimental plots in the Jari Cellulose and Tapajos National Forest areas over a 16-year period. Ten species groups are used to describe the natural processes affecting tree behaviour. Growth rates are calculated for each species group using the tree diameter and a competition index. Mortality and recruitment are simulated as stochastic processes. Recruitment probability is based on the predicted growth rate of a hypothetical tree. Options exist to vary the human interaction with the forest reflecting forest management decisions, as for other SYMFOR models. Model evaluation compares the performance of the model with data describing forest recovery for 16 years following logging. The model was applied to simulate current forest management practice in the Brazilian Amazon, with 40 m(3) ha(-1) of timber extracted with a cutting cycle of 30 years. Results show that yields are sustained for three harvests following the first logging of primary forest, but that the composition of timber moves towards lightwooded species rather than hardwooded. The predicted size of extracted trees decreases and the number of trees extracted increases with successive harvests, leading to a prediction of increased costs and lower profits for the logging company despite constant yields. The standing volume of all trees just before harvest is reduced by 15% over 150 years, with pioneer species becoming increasingly prevalent in the stand. The model, in the SYMFOR framework, can be used to help understand the differences between alternative forest management strategies in the Brazilian Amazon. Such knowledge is required to improve forest management, regulation and certification, and help to conserve the worlds largest remaining tropical forest. (C) 2003 Elsevier B.V. All rights reserved.  
  Address EMBRAPA Amazonia Oriental, BR-69011970 Manaus, Amazonas, Brazil, Email: Paul.Phillips@envams.co.uk  
  Corporate Author Thesis  
  Publisher ELSEVIER SCIENCE BV Place of Publication Editor  
  Language (down) Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0304-3800 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000220392200002 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 238  
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Author de Grandcourt, A.; Epron, D.; Montpied, P.; Louisanna, E.; Bereau, M.; Garbaye, J.; Guehl, J.M. openurl 
  Title Contrasting responses to mycorrhizal inoculation and phosphorus availability in seedlings of two tropical rainforest tree species Type Journal Article
  Year 2004 Publication New Phytologist Abbreviated Journal New Phytol.  
  Volume 161 Issue 3 Pages 865-875  
  Keywords phosphorus; growth; efficiency; Paris-type arbuscular mycorrhizas; tropical rainforest; seedlings; Dicorynia guianensis; Eperua falcata  
  Abstract This work aimed at understanding the role of mycorrhizal status in phosphorus efficiency of tree seedlings in the tropical rainforest of French Guyana. Mycorrhizal colonization, growth, phosphorus content, net photosynthesis and root respiration were determined on three occasions during a 9-month growth period for seedlings of two co-occurring species (Dicorynia guianensis and Eperua falcata) grown at three soil phosphorus concentrations, with or without inoculation with arbuscular mycorrhizas. Seedlings of both species were unable to absorb phosphorus in the absence of mycorrhizal association. Mycorrhizal seedlings exhibited coils that are specific of Paris-type mycorrhizae. Both species benefited from the mycorrhizal symbiosis in terms of phosphorus acquisition but the growth of E. falcata seedlings was unresponsive to this mycorrhizal improvement of phosphorus status, probably because of the combination of high seed mass and P reserves, with low growth rate. The two species belong to two different functional groups regarding phosphorus acquisition, D. guianensis being an obligate mycotrophic species.  
  Address Univ Franche Comte, Lab Biol & Ecophysiol, F-25211 Montbeliard, France, Email: daniel.epron@scbiol.uhp-nancy.fr  
  Corporate Author Thesis  
  Publisher BLACKWELL PUBLISHING LTD Place of Publication Editor  
  Language (down) 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:000188646500022 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 239  
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Author Dutech, C.; Joly, H.I.; Jarne, P. openurl 
  Title Gene flow, historical population dynamics and genetic diversity within French Guianan populations of a rainforest tree species, Vouacapoua americana Type Journal Article
  Year 2004 Publication Heredity Abbreviated Journal Heredity  
  Volume 92 Issue 2 Pages 69-77  
  Keywords bottleneck; climatic change; extinction-recolonization; microsatellite; neotropical rainforest; pollen and seed dispersal  
  Abstract Both gene flow and historical events influence the genetic diversity of natural populations. One way to understand their respective impact is to analyze population genetic structure at large spatial scales. We studied the distribution of genetic diversity of 17 populations of Vouacapoua americana (Caesalpiniaceae) in French Guiana, using nine micro satellite loci. Low genetic diversity was observed within populations, with a mean allelic richness and gene diversity of 4.1 and 0.506, respectively, which could be due to low effective population size and/or past bottlenecks. Using the regression between F-st/(1-F-st), estimated between pairs of populations, and the logarithm of the geographical distance, the spatial genetic structure can partly be explained by isolation-by-distance and limited gene flow among populations. This result is in agreement with the species' biology, including seed and pollen dispersal by rodents and insects, respectively. In contrast, no clear genetic signal of historical events was found when examining genetic differentiation among populations in relation to biogeographical hypotheses or by testing for bottlenecks within populations. Our conclusion is that nuclear spatial genetic structure of V. americana, at the geographic scale of French Guiana, is better explained by gene flow rather than by historical events.  
  Address Cirad Foret Silvolab, Lab Genet & Ecol Mol, F-97387 Kourou, France, Email: cdutech@bordeaux.inra.fr  
  Corporate Author Thesis  
  Publisher NATURE PUBLISHING GROUP Place of Publication Editor  
  Language (down) Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0018-067X ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000188431700003 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 240  
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