toggle visibility Search & Display Options

Select All    Deselect All
 |   | 
Details
   print
  Records Links (down)
Author Molto, Q.; Rossi, V.; Blanc, L. url  openurl
  Title Error propagation in biomass estimation in tropical forests Type Journal Article
  Year 2013 Publication Methods in Ecology and Evolution Abbreviated Journal  
  Volume 4 Issue 2 Pages 175-183  
  Keywords Bayesian framework; Modelling; Redd; Uncertainty propagation  
  Abstract Reliable above-ground biomass (AGB) estimates are required for studies of carbon fluxes and stocks. However, there is a huge lack of knowledge concerning the precision of AGB estimates and the sources of this uncertainty. At the tree level, the tree height is predicted using the tree diameter at breast height (DBH) and a height sub-model. The wood-specific gravity (WSG) is predicted with taxonomic information and a WSG sub-model. The tree mass is predicted using the predicted height, the predicted WSG and the biomass sub-model. Our models were inferred with Bayesian methods and the uncertainty propagated with a Monte Carlo scheme. The uncertainties in the predictions of tree height, tree WSG and tree mass were neglected sequentially to quantify their contributions to the uncertainty in AGB. The study was conducted in French Guiana where long-term research on forest ecosystems provided an outstanding data collection on tree height, tree dynamics, tree mass and species WSG. We found that the uncertainty in the AGB estimates was found to derive primarily from the biomass sub-model. The models used to predict the tree heights and WSG contributed negligible uncertainty to the final estimate. Considering our results, a poor knowledge of WSG and the height-diameter relationship does not increase the uncertainty in AGB estimates. However, it could lead to bias. Therefore, models and databases should be used with care. This study provides a methodological framework that can be broadly used by foresters and plant ecologist. It provides the accurate confidence intervals associated with forest AGB estimates made from inventory data. When estimating region-scale AGB values (through spatial interpolation, spatial modelling or satellite signal treatment), the uncertainty of the forest AGB value in the reference forest plots has to be taken in account. We believe that in the light of the Reducing Emissions from Deforestation and Degradation debate, our method is a crucial step in monitoring carbon stocks and their spatio-temporal evolution. © 2012 The Authors. Methods in Ecology and Evolution © 2012 British Ecological Society.  
  Address CIRAD, UMR 'Ecologie des Forêts de Guyane', Kourou Cedex, 97 379, 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 Export Date: 21 February 2013; Source: Scopus Approved no  
  Call Number EcoFoG @ webmaster @ Serial 470  
Permanent link to this record
 

 
Author Aimene, Y.; Dorville, R.; Omrane, A. url  openurl
  Title Optimal control for trees trunk diameter estimation in rain forest ecology Type Journal Article
  Year 2013 Publication Applied Mathematical Sciences Abbreviated Journal  
  Volume 7 Issue 17-20 Pages 807-816  
  Keywords Missing data; Optimal control; Tree trunk diameter  
  Abstract We study the optimal control question for an important mechanical problem related to tree trunk diameter variation in tropical forest ecology where some data are missing. Within a cost function, the control problem is formulated with a mechanical model that requires boundary conditions tosolve all equations. We give a characterization of the optimal measurement function for the tree trunk problem.  
  Address Laboratoire CEREGMIA EA 2440, Université Antilles-Guyane, I.E.S.G Campus de Trou-Biran, Route de Baduel, 97337 Cayenne, 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 ISBN Medium  
  Area Expedition Conference  
  Notes Export Date: 21 February 2013; Source: Scopus Approved no  
  Call Number EcoFoG @ webmaster @ Serial 469  
Permanent link to this record
 

 
Author Fromin, N.; Saby, N.P.A.; Lensi, R.; Brunet, D.; Porte, B.; Domenach, A.-M.; Roggy, J.-C. url  doi
openurl 
  Title Spatial variability of soil microbial functioning in a tropical rainforest of French Guiana using nested sampling Type Journal Article
  Year 2013 Publication Geoderma Abbreviated Journal  
  Volume 197-198 Issue Pages 98-107  
  Keywords Denitrification; Respiration; Scale dependent process; Soil microbial processes; Soil organic matter; Tree influence potential  
  Abstract Understanding the pattern in spatial distribution of soil microbial processes is critical to understand the environmental factors that regulate them as well as to scale up these processes to ecosystem. Soil samples from a 1. ha tropical rainforest plot (Paracou, French Guiana) were analyzed according a nested sampling approach using different separation distances ranging from 0.4 to 40. m. The variability of substrate induced respiration (SIR) and of denitrification enzyme activity (DEA) was characterized in relation to various soil properties (total C and N contents, NIRS related index of soil organic matter quality, SOMQ, and index of tree influence potential, IP). The variability of SIR and DEA was higher than that of environmental properties. The patterns of accumulated variance as a function of distance varied among the soil properties. The variability of SIR and DEA mainly occurred at small (1. m) scale (and at the 10-40. m-scales for SIR), probably reflecting the quality of litter input that results of the influence of local assemblage of different tree species, though changes in the soil N and C contents. Indeed, total soil C and N contents explained the microbial properties at every scale. Coefficients of codispersion showed that neither SOMQ nor IP did correlate with SIR and DEA, and confirmed that total C and N contents explained microbial properties in a scale dependent and complex manner. Such spatial dependency underlines the importance of soil heterogeneity in this tropical forest with implications for sampling strategies when studying the microbial processes and their response to disturbances. © 2012 Elsevier B.V.  
  Address UMR EcoFoG, BP 709, 97387 Kourou, GUF, 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 Export Date: 13 February 2013; Source: Scopus Approved no  
  Call Number EcoFoG @ webmaster @ Serial 466  
Permanent link to this record
 

 
Author Ruiz-González, M.X.; Lauth, J.; Leroy, C.; Jauneau, A.; Gryta, H.; Jargeat, P.; Dejean, A.; Orivel, J. url  openurl
  Title An efficient protocol for isolating melanised chaetothyrialean anamorphic fungi associated with plant-ants Type Journal Article
  Year 2013 Publication Journal of Basic Microbiology Abbreviated Journal  
  Volume 53 Issue 1 Pages 98-100  
  Keywords Allomerus ants; Black fungi; Chaetothyriales; Fluorescent staining; Isolation method  
  Abstract Because of their ecological characteristics, slow growth rates and the presence of contaminants, Chaetothyriales fungi associated with structures built by tropical plant-ants can be difficult to isolate with standard procedures. Here, we describe an easy-to-use protocol for obtaining pure cultures by using cotton as a first substrate. We have further found by means of fluorescent stains that nuclei concentrate either in young hyphae or in the tips of the hyphae. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.  
  Address Université de Toulouse, ECOLAB, Toulouse, 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 Export Date: 6 February 2013; Source: Scopus Approved no  
  Call Number EcoFoG @ webmaster @ Serial 461  
Permanent link to this record
 

 
Author Barabe, D.; Cuerrier, A.; Quilichini, A. url  openurl
  Title Botanical gardens: Between science and commercialization Type Journal Article
  Year 2012 Publication Natures Sciences Societes Abbreviated Journal  
  Volume 20 Issue 3 Pages 334-342  
  Keywords  
  Abstract Les jardins botaniques: Entre science et commercialisation.  
  Address Enseignante-chercheure en Écologie, CNRS, UMR8172 Icologie des Dorêts de Guyane, 97387 Kourou, 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 Export Date: 3 January 2013; Source: Scopus Approved no  
  Call Number EcoFoG @ webmaster @ Serial 455  
Permanent link to this record
 

 
Author Maia, A.C.D.; Gibernau, M.; Carvalho, A.T.; Gonçalves, E.G.; Schlindwein, C. url  openurl
  Title The cowl does not make the monk: Scarab beetle pollination of the Neotropical aroid Taccarum ulei (Araceae: Spathicarpeae) Type Journal Article
  Year 2013 Publication Biological Journal of the Linnean Society Abbreviated Journal  
  Volume 108 Issue 1 Pages 22-34  
  Keywords Flower predation; Nocturnal pollinators; Pollination syndromes; Scarabaeidae; Thermogenesis  
  Abstract Taccarum ulei (Araceae, Spathicarpeae) is a seasonal geophytic aroid, native to north-eastern Brazil, that flowers during two months of the rainy season. Patterns of floral thermogenesis, pollination biology, and floral traits associated with pollination syndromes were studied and compared with those of other Araceae. Two species of cyclocephaline scarabs (Scarabaeidae, Cyclocephalini) were recognized as effective pollinators: Cyclocephala celata and Cyclocephala cearae. Larvae of an unidentified species of fruit fly (Melanolomaspp., Richardiidae, Diptera) were also frequently observed in inflorescences at various maturation stages, feeding on the connectives of male florets and fruits, and thus lowering the reproductive success of individual plants. Beetles were attracted by odoriferous inflorescences in the early evening of the first day of anthesis, during the female phase. The emission of attractive volatiles was coupled with intense thermogenic activity in the entire spadix, unlike other aroids in which only certain zones of the spadix heat up. Pollen release, which marks the beginning of the male phase on the subsequent evening, was not related to floral thermogenesis. Comparative multivariate analysis of the floral traits of T.ulei points to a beetle-pollinated aroid, although some of the observed traits of the species are not common to other taxa sharing this pollination strategy. Such incongruence might be explained by the evolutionary history of the tribe Spathicarpeae and potential pollinator shifts. © 2012 The Linnean Society of London.  
  Address Departamento de Botânica, Universidade Federal de Minas Gerais, Belo Horizonte, 31270-901, Brazil  
  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 Export Date: 3 January 2013; Source: Scopus Approved no  
  Call Number EcoFoG @ webmaster @ Serial 453  
Permanent link to this record
 

 
Author Fanin, N.; Barantal, S.; Fromin, N.; Schimann, H.; Schevin, P.; Hattenschwiler, S. pdf  url
openurl 
  Title Distinct Microbial Limitations in Litter and Underlying Soil Revealed by Carbon and Nutrient Fertilization in a Tropical Rainforest Type Journal Article
  Year 2012 Publication PLoS ONE Abbreviated Journal  
  Volume 7 Issue 12 Pages e49990  
  Keywords  
  Abstract Human-caused alterations of the carbon and nutrient cycles are expected to impact tropical ecosystems in the near future. Here we evaluated how a combined change in carbon (C), nitrogen (N) and phosphorus (P) availability affects soil and litter microbial respiration and litter decomposition in an undisturbed Amazonian rainforest in French Guiana. In a fully factorial C (as cellulose), N (as urea), and P (as phosphate) fertilization experiment we analyzed a total of 540 litterbag-soil pairs after a 158-day exposure in the field. Rates of substrate-induced respiration (SIR) measured in litter and litter mass loss were similarly affected by fertilization showing the strongest stimulation when N and P were added simultaneously. The stimulating NP effect on litter SIR increased considerably with increasing initial dissolved organic carbon (DOC) concentrations in litter, suggesting that the combined availability of N, P, and a labile C source has a particularly strong effect on microbial activity. Cellulose fertilization, however, did not further stimulate the NP effect. In contrast to litter SIR and litter mass loss, soil SIR was reduced with N fertilization and showed only a positive effect in response to P fertilization that was further enhanced with additional C fertilization. Our data suggest that increased nutrient enrichment in the studied Amazonian rainforest can considerably change microbial activity and litter decomposition, and that these effects differ between the litter layer and the underlying soil. Any resulting change in relative C and nutrient fluxes between the litter layer and the soil can have important consequences for biogeochemical cycles in tropical forest ecosystems. © 2012 Fanin et al.  
  Address UMR Ecologie des Forêts de Guyane (EcoFoG), Campus Agronomique, 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 ISBN Medium  
  Area Expedition Conference  
  Notes Export Date: 3 January 2013; Source: Scopus; Art. No.: e49990 Approved no  
  Call Number EcoFoG @ webmaster @ Serial 454  
Permanent link to this record
 

 
Author Basset, Y.; Cizek, L.; Cuénoud, P.; Didham, R.K.; Guilhaumon, F.; Missa, O.; Novotny, V.; Ødegaard, F.; Roslin, T.; Schmidl, J.; Tishechkin, A.K.; Winchester, N.N.; Roubik, D.W.; Aberlenc, H.-P.; Bail, J.; Barrios, H.; Bridle, J.R.; Castaño-Meneses, G.; Corbara, B.; Curletti, G.; Da Rocha, W.D.; De Bakker, D.; Delabie, J.H.C.; Dejean, A.; Fagan, L.L.; Floren, A.; Kitching, R.L.; Medianero, E.; Miller, S.E.; De Oliveira, E.G.; Orivel, J.; Pollet, M.; Rapp, M.; Ribeiro, S.P.; Roisin, Y.; Schmidt, J.B.; Sørensen, L.; Leponce, M. url  openurl
  Title Arthropod diversity in a tropical forest Type Journal Article
  Year 2012 Publication Science Abbreviated Journal  
  Volume 338 Issue 6113 Pages 1481-1484  
  Keywords  
  Abstract Most eukaryotic organisms are arthropods. Yet, their diversity in rich terrestrial ecosystems is still unknown. Here we produce tangible estimates of the total species richness of arthropods in a tropical rainforest. Using a comprehensive range of structured protocols, we sampled the phylogenetic breadth of arthropod taxa from the soil to the forest canopy in the San Lorenzo forest, Panama. We collected 6144 arthropod species from 0.48 hectare and extrapolated total species richness to larger areas on the basis of competing models. The whole 6000-hectare forest reserve most likely sustains 25,000 arthropod species. Notably, just 1 hectare of rainforest yields >60% of the arthropod biodiversity held in the wider landscape. Models based on plant diversity fitted the accumulated species richness of both herbivore and nonherbivore taxa exceptionally well. This lends credence to global estimates of arthropod biodiversity developed from plant models.  
  Address Natural History Museum of Denmark, 2100 Copenhagen, Denmark  
  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 Export Date: 27 December 2012; Source: Scopus Approved no  
  Call Number EcoFoG @ webmaster @ Serial 451  
Permanent link to this record
 

 
Author Mathieu, A.; Letort, V.; Cournède, P.H.; Zhang, B.G.; Heuret, P.; De Reffye, P. url  openurl
  Title Oscillations in functional structural plant growth models Type Journal Article
  Year 2012 Publication Mathematical Modelling of Natural Phenomena Abbreviated Journal  
  Volume 7 Issue 6 Pages 47-66  
  Keywords Cecropia trees; Cucumber plant; Dynamic system of plant growth; Functional-structural plant models; GreenLab  
  Abstract The dynamic model of plant growth GreenLab describes plant architecture and functional growth at the level of individual organs. Structural development is controlled by formal grammars and empirical equations compute the amount of biomass produced by the plant, and its partitioning among the growing organs, such as leaves, stems and fruits. The number of organs initiated at each time step depends on the trophic state of the plant, which is evaluated by the ratio of biomass available in plant to the demand of all the organs. The control of the plant organogenesis by this variable induces oscillations in the simulated plant behaviour. The mathematical framework of the GreenLab model allows to compute the conditions for the generation of oscillations and the value of the period according to the set of parameters. Two case-studies are presented, corresponding to emergence of oscillations associated to fructification and branching. Similar alternating patterns are commonly reported by botanists. In this article, two examples were selected: alternate patterns of fruits in cucumber plants and alternate appearances of branches in Cecropia trees. The model was calibrated from experimental data collected on these plants. It shows that a simple feedback hypothesis of trophic control on plant structure allows the emergence of cyclic patterns corresponding to the observed ones. © EDP Sciences, 2012.  
  Address CIRAD, UMR AMAP, Montpellier, 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 Export Date: 27 December 2012; Source: Scopus Approved no  
  Call Number EcoFoG @ webmaster @ Serial 452  
Permanent link to this record
 

 
Author Carrias, J.-F.; Brouard, O.; Leroy, C.; Céréghino, R.; Pélozuelo, L.; Dejean, A.; Corbara, B. url  openurl
  Title An ant-plant mutualism induces shifts in the protist community structure of a tank-bromeliad Type Journal Article
  Year 2012 Publication Basic and Applied Ecology Abbreviated Journal  
  Volume 13 Issue 8 Pages 698-705  
  Keywords Aechmea mertensii; Ant-garden; Biodiversity; Camponotus femoratus; French Guiana; Pachycondyla goeldii; Phytotelmata; Protists  
  Abstract Although ants may induce community-wide effects via changes in physical habitats in terrestrial environments, their influence on aquatic communities living in plant-held waters remains largely underexplored. The neotropical tank-bromeliad Aechmea mertensii (Bromeliaceae) occurs along forest edges in ant-gardens initiated by Camponotus femoratus or by Pachycondyla goeldii. Its leaves form wells that hold rainwater and provide suitable habitats for many aquatic organisms. We postulated that these ant-plant mutualisms indirectly affect the microbial community structure via changes in the environmental conditions experienced by the plants. To test this hypothesis, we analyzed the protist communities from 63 tank-bromeliads associated with either C. femoratus or P. goeldii (hereafter Cf-Aechmea and Pg-Aechmea) along a forest edge in French Guiana. For each plant, a large number of environmental variables (including habitat structure, food resources, incident radiation and the presence of aquatic invertebrates) were quantified to determine their relative importance in driving any observed differences across ant-associated plants. Pg-Aechmea are located in sun-exposed areas and hold low volumes of water and low amounts of detritus, whereas Cf-Aechmea are located in partially shaded areas and accumulate higher amounts of water and detritus. Protists (i.e., protozoa and algae) inhabiting Cf-Aechmea exhibit greater richness and abundances than those in Pg-Aechmea. Variations in detritus content, number of leaves, incident radiation, and the epiphyte richness of the ant-garden were the main factors explaining the variation in protist richness. A shift in the functional group composition of protists between bromeliads tended by different ant species suggested that mutualistic ants indirectly mediate changes in the microbial food web. © 2012 Gesellschaft für Ökologie.  
  Address Université de Toulouse; UPS, 118 route de Narbonne, 31062 Toulouse, 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 Export Date: 14 December 2012; Source: Scopus Approved no  
  Call Number EcoFoG @ webmaster @ Serial 449  
Permanent link to this record
Select All    Deselect All
 |   | 
Details
   print

Save Citations:
Export Records: