toggle visibility Search & Display Options

Select All    Deselect All
 |   | 
Details
   print
  Records Links
Author Rutishauser, E.; Barthelemy, D.; Blanc, L.; Nicolini, E.A. openurl 
  Title Crown fragmentation assessment in tropical trees: Method, insights and perspectives Type Journal Article
  Year 2011 Publication Forest Ecology and Management Abbreviated Journal For. Ecol. Manage.  
  Volume 261 Issue 3 Pages (down) 400-407  
  Keywords Crown assessment; Crown fragmentation; Tree mortality; Forest dynamics  
  Abstract Decreasing growth rate (Feeley et al., 2007) and large die-back due to drought (Phillips et al., 2009) suggest that tropical forests are suffering recent climate changes. Forest vulnerability to external factors (e.g. air pollution, acid rain) is widely studied in northern countries, while only a few attempts have investigated crown integrity in the Tropics. The method needs to be generic enough to account for the large number of species and crown shapes encountered in tropical forests. In the present study, we developed and tested a novel field method that estimates crown fragmentation (main branch mortality (MB) and secondary branch mortality (SB)), liana infestation (LI) and crown position (CP) in the canopy. The relationship between crown fragmentation and annual growth rate (agr) was investigated through multiple regression. Six out of eight canopy tree species showed significant growth decline with increasing crown fragmentation. Higher probability of death was also found in trees with severe crown fragmentation. The capacity of such crown assessment to depict tree vitality in a forest stand is discussed along with potential applications in both forest science and management. (C) 2010 Elsevier B.V. All rights reserved.  
  Address [Rutishauser, Ervan; Eric-Andre, Nicolini] Cirad UMR AMAP, F-34398 Montpellier 5, France, Email: er.rutishauser@gmail.com  
  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 0378-1127 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000287333000009 Approved no  
  Call Number EcoFoG @ webmaster @ Serial 293  
Permanent link to this record
 

 
Author McLean, J.P.; Arnould, O.; Beauchene, J.; Clair, B. url  openurl
  Title The effect of the G-layer on the viscoelastic properties of tropical hardwoods Type Journal Article
  Year 2012 Publication Annals of Forest Science Abbreviated Journal Ann. Forest Sci.  
  Volume 69 Issue 3 Pages (down) 399-408  
  Keywords Dma; G-layer; Reaction wood; Tropical wood; Viscoelasticity  
  Abstract · Context and aim This study aimed to examine the effect of the tension wood G-layer on the viscoelastic properties of wood. · Methods Tension wood and opposite wood samples were obtained from six French Guianese tropical rainforest species (Sextonia rubra, Ocotea guyanensis, Inga alba, Tachigali melinoni, Iyranthera sagotiana and Virola michelii); the tension wood of the former three of these species had a Glayer, whilst the tension wood from the latter three had no Glayer. Tensile dynamic mechanical analysis (DMA) was performed on green never dried wood samples in the longitudinal direction with samples submerged in a water bath at a temperature (30°C) and frequency (1 Hz) representative of the conditions experienced by wood within a living tree. Then, DMA was repeated with samples conditioned to an air-dried state. Finally, samples were oven-dried to measure longitudinal shrinkage. · Results Tension wood did not always have a higher longitudinal storage (elastic) modulus than opposite wood from the same tree regardless of the presence or absence of a G-layer. For the species containing a G-layer, tension wood had a higher damping coefficient and experienced a greater longitudinal shrinkage upon drying than opposite wood from the same species. No difference was found in damping coefficients between tension wood and opposite wood for the species that had no G-layer. · Conclusion It is proposed that the different molecular composition of the G-layer matrix has an influence on the viscoelasticity of wood, even if a biomechanical gain is not yet clear. This study shows that rheological properties and longitudinal shrinkage can be used to detect the presence of a G-layer in tension wood. © INRA/Springer-Verlag France 2011.  
  Address UMR Ecologie des Forêts de Guyane (ECOFOG), CIRAD, Kourou, French Guiana  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 12864560 (Issn) ISBN Medium  
  Area Expedition Conference  
  Notes Export Date: 20 June 2012; Source: Scopus; Coden: Afosf; doi: 10.1007/s13595-011-0164-1; Language of Original Document: English; Correspondence Address: McLean, J.P.; Forest Products Research Institute, Edinburgh Napier University, Merchiston Campus, Edinburgh EH10 5DT, United Kingdom; email: p.mclean@napier.ac.uk Approved no  
  Call Number EcoFoG @ webmaster @ Serial 404  
Permanent link to this record
 

 
Author Bompy, F.; Lequeue, G.; Imbert, D.; Dulormne, M. doi  openurl
  Title Increasing fluctuations of soil salinity affect seedling growth performances and physiology in three Neotropical mangrove species Type Journal Article
  Year 2014 Publication Plant and Soil Abbreviated Journal Plant and Soil  
  Volume 380 Issue 1 Pages (down) 399-413  
  Keywords Acclimation; Avicennia germinans; Hypersalinity; Laguncularia racemosa; Leaf gas exchange; Rhizophora mangle; Salt stress  
  Abstract Background: Micro-tidal wetlands are subject to strong seasonal variations of soil salinity that are likely to increase in amplitude according to climate model predictions for the Caribbean. Whereas the effects of constant salinity levels on the physiology of mangrove species have been widely tested, little is known about acclimation to fluctuations in salinity. Aims and methods: The aim of this experiment was to characterize the consequences of the rate of increase in salinity (slow versus fast) and salinity fluctuations over time versus constant salt level. Seedling mortality, growth, and leaf gas exchange of three mangrove species, Avicennia germinans, Laguncularia racemosa, and Rhizophora mangle were investigated in semicontrolled conditions at different salt levels (0, 685, 1025, and 1370 mM NaCl). Results: Slow salinity increase up to 685 mM induced acclimation, improving the salt tolerance of A. germinans and L. racemosa, but had no effect on R. mangle. During fluctuations between 0 and 685 mM, A. germinans and R. mangle were not affected by a salinity drop to zero, whereas L. racemosa took advantage of the brief freshwater episode as shown by the durable improvement of photosynthesis and biomass production. Conclusions: This study provides new insights into physiological resistance and acclimation to salt stress. We show that seasonal variations of salinity may affect mangrove seedlings' morphology and physiology as much as annual mean salinity. Moreover, more severe dry seasons due to climate change may impact tree stature and species composition in mangroves through higher mortality rates and physiological disturbance at the seedling stage. © 2014 Springer International Publishing Switzerland.  
  Address EA 926 DYNECAR, UFR des Sciences Exactes et Naturelles, Université des Antilles et de la Guyane, BP 592, 97 159 Pointe-à-Pitre cedex, Guadeloupe (F.W.I.), France  
  Corporate Author Thesis  
  Publisher 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 Cited By :7; Export Date: 7 February 2017 Approved no  
  Call Number EcoFoG @ webmaster @ Serial 726  
Permanent link to this record
 

 
Author Stahl, C.; Burban, B.; Bompy, F.; Jolin, Z.B.; Sermage, J.; Bonal, D. openurl 
  Title Seasonal variation in atmospheric relative humidity contributes to explaining seasonal variation in trunk circumference of tropical rain-forest trees in French Guiana Type Journal Article
  Year 2010 Publication Journal of Tropical Ecology Abbreviated Journal J. Trop. Ecol.  
  Volume 26 Issue Pages (down) 393-405  
  Keywords bark; drought; secondary growth; seasonality; tropical rain forest; water  
  Abstract Large seasonal variation in the rate of change in girth of tropical rain-forest tree species has been described, but its origin is still under debate. We tested whether this variation might be related to variation in atmospheric relative humidity through its influence on bark water content and thickness. Variation in trunk circumference of 182 adult trees was measured about twice a month in an undisturbed tropical rain forest over 18 mo using dendrometers. Furthermore, a laboratory experiment was conducted to test the direct influence of relative air humidity on bark water content and thickness. in the field, most trees displayed highly positive rates of change in girth at the onset of the wet season, while a quarter of the trees displayed negative changes during long dry seasons, whatever their total annual growth. This variation was correlated with environmental conditions, particularly with atmospheric relative humidity. Trees with high bark water content and thickness displayed a stronger decrease in girth during the dry season. in the chamber experiment, desiccation induced a decrease in the diameter of the trunk sections in tandem with a decrease in bark water content. As a result, seasonal variation in the rate of change in girth of tropical rain-forest trees reflects variation in trunk biophysical properties, through the influence of relative humidity on bark properties. but not directly variation in secondary growth.  
  Address [Stahl, Clement; Burban, Benoit; Bompy, Felix; Jolin, Zachari B.; Sermage, Juliette; Bonal, Damien] INRA, UMR Ecol Forets Guyane 745, Kourou 97387, French Guiana, Email: bonal@nancy.inra.fr  
  Corporate Author Thesis  
  Publisher CAMBRIDGE UNIV PRESS Place of Publication Editor  
  Language 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:000279100600005 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 57  
Permanent link to this record
 

 
Author Hattenschwiler, S.; Fromin, N.; Barantal, S. openurl 
  Title Functional diversity of terrestrial microbial decomposers and their substrates Type Journal Article
  Year 2011 Publication Comptes Rendus Biologies Abbreviated Journal C. R. Biol.  
  Volume 334 Issue 5-6 Pages (down) 393-402  
  Keywords Bacteria; Biogeochemical cycles; Decomposition; Dissimilarity; Ecosystem functioning; Functional diversity indices; Fungi; Leaf litter  
  Abstract The relationship between biodiversity and biogeochemical processes gained much interest in light of the rapidly decreasing biodiversity worldwide. In this article, we discuss the current status, challenges and prospects of functional concepts to plant litter diversity and microbial decomposer diversity. We also evaluate whether these concepts permit a better understanding of how biodiversity is linked to litter decomposition as a key ecosystem process influencing carbon and nutrient cycles. Based on a literature survey, we show that plant litter and microbial diversity matters for decomposition, but that considering numbers of taxonomic units appears overall as little relevant and less useful than functional diversity. However, despite easily available functional litter traits and the well-established theoretical framework for functional litter diversity, the impact of functional litter diversity on decomposition is not yet well enough explored. Defining functional diversity of microorganisms remains one of the biggest challenges for functional approaches to microbial diversity. Recent developments in microarray and metagenomics technology offer promising possibilities in the assessment of the functional structure of microbial communities. This might allow significant progress in measuring functional microbial diversity and ultimately in our ability to predict consequences of biodiversity loss in the decomposer system for biogeochemical processes. (C) 2011 Academie des sciences. Published by Elsevier Masson SAS. All rights reserved.  
  Address [Haettenschwiler, Stephan; Fromin, Nathalie; Barantal, Sandra] CNRS, CEFE, F-34293 Montpellier 5, France, Email: stephan.hattenschwiler@cefe.cnrs.fr  
  Corporate Author Thesis  
  Publisher Elsevier France-Editions Scientifiques Medicales Elsevier Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1631-0691 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000292013400008 Approved no  
  Call Number EcoFoG @ webmaster @ Serial 323  
Permanent link to this record
 

 
Author Ruiz-González, M.X.; Leroy, C.; Dejean, A.; Gryta, H.; Jargeat, P.; Carrión, A.D.A.; Orivel, J. pdf  url
doi  openurl
  Title Do host plant and associated ant species affect microbial communities in myrmecophytes? Type Journal Article
  Year 2019 Publication Insects Abbreviated Journal Insects  
  Volume 10 Issue 11 Pages (down) 391  
  Keywords Allomerus decemarticulatus; Allomerus octoarticulatus; Azteca sp; Cf; Cordia nodosa; Depilis; Domatia; Hirtella physophora; Microbial diversity  
  Abstract Ant-associated microorganisms can play crucial and often overlooked roles, and given the diversity of interactions that ants have developed, the study of the associated microbiomes is of interest. We focused here on specialist plant-ant species of the genus Allomerus that grow a fungus to build galleries on their host-plant stems. Allomerus-inhabited domatia, thus, might be a rich arena for microbes associated with the ants, the plant, and the fungus. We investigated the microbial communities present in domatia colonised by four arboreal ants: Allomerus decemarticulatus, A. octoarticulatus, A. octoarticulatus var. demerarae, and the non-fungus growing plant-ant Azteca sp. cf. depilis, inhabiting Hirtella physophora or Cordia nodosa in French Guiana. We hypothesized that the microbial community will differ among these species. We isolated microorganisms from five colonies of each species, sequenced the 16S rRNA or Internal TranscribedSpacer (ITS) regions, and described both the alpha and beta diversities. We identified 69 microbial taxa, which belong to five bacterial and two fungal phyla. The most diverse phyla were Proteobacteria and Actinobacteria. The microbial community of Azteca cf. depilis and Allomerus spp. differed in composition and richness. Geographical distance affected microbial communities and richness but plant species did not. Actinobacteria were only associated with Allomerus spp.  
  Address Biodiversity Genomics Team, Plant Ecophysiology & Evolution Group, Guangxi Key Laboratory of Forest Ecology and Conservation, College of Forestry, Daxuedonglu 100, Nanning, Guangxi 530005, China  
  Corporate Author Thesis  
  Publisher Mdpi Ag Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 20754450 (Issn) ISBN Medium  
  Area Expedition Conference  
  Notes Export Date: 18 November 2019; Correspondence Address: Ruiz-González, M.X.; Departamento de Ciencias Biológicas, Universidad Técnica Particular de Loja, San Cayetano Alto s/n, Ecuador; email: marioxruizgonzalez@gmail.com Approved no  
  Call Number EcoFoG @ webmaster @ Serial 896  
Permanent link to this record
 

 
Author Céréghino, R.; Corbara, B.; Leroy, C.; Carrias, J.-F. doi  openurl
  Title Ecological determinants of community structure across the trophic levels of freshwater food webs: a test using bromeliad phytotelmata Type Journal Article
  Year 2020 Publication Hydrobiologia Abbreviated Journal Hydrobiologia  
  Volume 847 Issue 2 Pages (down) 391-402  
  Keywords Environmental filtering; Functional group; Neotropical; Niche; Trophic interactions; alga; assembly rule; bacterium; community structure; ecological modeling; environmental conditions; food web; freshwater ecosystem; functional group; Neotropic Ecozone; niche; protozoan; taxonomy; trophic interaction; trophic level; algae; Invertebrata; Protozoa  
  Abstract Understanding the relative importance of habitat and biotic drivers on community assembly across food web components is an important step towards predicting the consequences of environmental changes. Because documenting entire food webs is often impractical, this question has been only partially investigated. Here, we partitioned variation in species assemblages of the major components of tank bromeliad food webs (bacteria, algae, protozoans, detritivorous and predatory invertebrates) into habitat and biotic determinants and examined the influence of habitat variables and predator or prey abundance on all taxonomic assemblages. Ecological determinism of assemblage structure ranged from weak in bacteria (< 10% of the explained variance) to strong in predatory invertebrates (90%). Habitat features and canopy openness significantly influenced species assemblages; however, prey or predator density had far and away the most significant structuring effects. If biotic forces are at least as important as the abiotic forces while the importance of stochasticity declines towards upper trophic levels, then trophic levels could respond differently to natural or anthropogenic disturbance and to shifts in species distributions. The effects of such differential responses on food web reconfiguration, however, remain to be elucidated. © 2019, Springer Nature Switzerland AG.  
  Address UMR EcoFoG (AgroParisTech, CIRAD, CNRS, INRA, Université de Guyane, Université des Antilles), Kourou, 97310, France  
  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 00188158 (Issn) ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number EcoFoG @ webmaster @ Serial 996  
Permanent link to this record
 

 
Author Schmitt, Sylvain ; Derroire, Géraldine ; Tysklind, Niklas ; Heuertz, Myriam ; Hérault, Bruno doi  openurl
  Title Topography shapes the local coexistence of tree species within species complexes of Neotropical forests Type Journal Article
  Year 2021 Publication Oecologia Abbreviated Journal  
  Volume 196 Issue Pages (down) 389-398  
  Keywords  
  Abstract Forest inventories in Amazonia include around 5000 described tree species belonging to more than 800 genera. Numerous species-rich genera share genetic variation among species because of recent speciation and/or recurrent hybridisation, forming species complexes. Despite the key role that tree species complexes play in understanding Neotropical diversification, and their need to exploit a diversity of niches, little is known about the mechanisms that allow local coexistence of tree species complexes and their species in sympatry. In this study, we explored the fine-scale distribution of five tree species complexes and 22 species within these complexes. Combining forest inventories, botanical determination, and LiDAR-derived topographic data over 120 ha of permanent plots in French Guiana, we used a Bayesian modelling framework to test the role of fine-scale topographic wetness and tree neighbourhood on the occurrence of species complexes and the relative distribution of species within complexes. Species complexes of Neotropical trees were widely spread across the topographic wetness gradient at the local scale. Species within complexes showed pervasive niche differentiation along with topographic wetness and competition gradients. Similar patterns of species-specific habitat preferences were observed within several species complexes: species more tolerant to competition for resources grow in drier and less fertile plateaus and slopes. If supported by partial reproductive isolation of species and adaptive introgression at the species complex level, our results suggest that both species-specific habitat specialisation within species complexes and the broad ecological distribution of species complexes might explain the success of these species complexes at the regional scale.  
  Address  
  Corporate Author Thesis  
  Publisher Springer Link 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 Approved no  
  Call Number EcoFoG @ webmaster @ Serial 1018  
Permanent link to this record
 

 
Author Lobova, T.A.; Mori, S.A.; Blanchard, F.; Peckham, H.; Charles-Dominique, P. openurl 
  Title Cecropia as a food resource for bats in French Guiana and the significance of fruit structure in seed dispersal and longevity Type Journal Article
  Year 2003 Publication American Journal of Botany Abbreviated Journal Am. J. Bot.  
  Volume 90 Issue 3 Pages (down) 388-403  
  Keywords bat dispersal; Cecropia; French Guiana; fruit anatomy; fruit morphology; mucilage; Neotropical bats; soil seed bank  
  Abstract Cecropia (Cecropiaceae) is a Neotropical genus of pioneer plants. A review of bat/plant dispersal interactions revealed that 15 species of Cecropia are consumed by 32 species of bats. In French Guiana, bats were captured in primary and secondary forests, yielding 936 fecal samples with diaspores, among which 162 contained fruits of C. obtusa, C. palmata, and C. sciadophylla. A comparative morphological and anatomical study of fruits and seeds taken directly from herbarium specimens, bat feces, and an experimental soil seed bank was made. Contrary to previous reports, the dispersal unit of Cecropia is the fruit not the seed. Bats consume the infructescence, digest pulp derived from the enlarged, fleshy perianth, and defecate the fruits. The mucilaginous pericarp of Cecropia is described. The external mucilage production of Cecropia may facilitate endozoochory. The exocarp and part of the mesocarp may be lost after passage through the digestive tract of bats, but fruits buried for a year in the soil seed bank remain structurally unchanged. Fruit characters were found to be useful for identifying species of bat-dispersed Cecropia. Bat dispersal is not necessary for seed germination but it increases seed survival and subsequent germination. Fruit structure plays a significant role in seed longevity.  
  Address New York Bot Garden, Inst Systemat Bot, Bronx, NY 10458 USA  
  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:000183133100008 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 272  
Permanent link to this record
 

 
Author Degen, B.; Blanc, L.; Caron, H.; Maggia, L.; Kremer, A.; Gourlet-Fleury, S. openurl 
  Title Impact of selective logging on genetic composition and demographic structure of four tropical tree species Type Journal Article
  Year 2006 Publication Biological Conservation Abbreviated Journal Biol. Conserv.  
  Volume 131 Issue 3 Pages (down) 386-401  
  Keywords demography; genetic diversity; logging; phenology; pollen and seed dispersal; simulation; trees; tropics  
  Abstract Over-exploitation and fragmentation are serious problems for tropical forests. Most sustainable forest management practices avoid clear-cuts and apply selective logging systems focused on a few commercial species. We applied a simulation model to estimate the impact of such selective logging scenarios on the genetic diversity and demography of four tropical tree species from French Guiana. The simulations used data on genetic and demographic composition, growth, phenology and pollen and seed dispersal obtained for Dicorynia guianensis, Sextonia rubra, Symphonia globulifera and Vouacapoua americana at the experimental site in Paracou. Whereas Symphonia globulifera serves as a model for a species with low logging pressure, the other three species represent the most exploited tree species in French Guiana. In simulations with moderate logging, typical for French Guiana, with large cutting diameter (> 60 cm diameter) and long cutting cycles (65 years), the two species V. americana and Sextonia rubra were not able to recover their initial stock at the end of the rotation period, with a large decrease in the number of individuals and in basal area. Under a more intensive logging system (cutting diameter > 45 cm diameter, cutting cycles of 30 years) that is common practice in the Brazilian Amazon, only Symphonia globulifera showed no negative impact. Generally, the differences between the genetic parameters in the control scenarios without logging and the logging scenarios were surprisingly small. The main reasons for this were the overlapping of generations and the effective dispersal ability of gene vectors in all species, which guarantee relative homogeneity of the genetic structure in different age classes. Nevertheless, decreasing the population size by logging reduced the number of genotypes and caused higher genetic distances between the original population and the population at the end of the logging cycles. Sensitivity analysis showed that genetic changes in the logging scenarios were principally determined by the growth, densities and cutting diameter of each species, and only to a very small extent by the reproductive system including factors such as pollen and seed dispersal and flowering phenology. (c) 2006 Elsevier Ltd. All rights reserved.  
  Address BFH, Inst Forstgenet & Forstpflanzenzuchtung, D-22927 Grosshansdorf, Germany, Email: b.degen@holz.uni-hamburg.de  
  Corporate Author Thesis  
  Publisher ELSEVIER SCI LTD Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0006-3207 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000239139400004 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 180  
Permanent link to this record
Select All    Deselect All
 |   | 
Details
   print

Save Citations:
Export Records: