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Author Leroy, C.; Corbara, B.; Dejean, A.; Céréghino, R.
Title Potential sources of nitrogen in an ant-garden tank-bromeliad Type Journal Article
Year 2009 Publication Plant Signaling and Behavior Abbreviated Journal Plant. Signal. Behav.
Volume 4 Issue 9 Pages 868-870
Keywords Aechmea mertensii Camponotus femoratus nitrogen nitrogen stable isotope Pachycondyla goeldii plant-insect interactions phytotelmata
Abstract Epiphytic plants in general and bromeliads in particular live in a water and nutrient-stressed environment often limited in nitrogen. Thus, these plants have developed different ways to survive in such an environment. We focused on Aechmea mertensii (Bromeliaceae), which is both a tank-bromeliad and an ant-garden (AG) epiphyte initiated by either the ants Camponotus femoratus or Pachycondyla goeldii. By combining a study of plant morphology and physiology associated with aquatic insect biology, we demonstrate that the ant species influences the leaf structure of the bromeliad, the structure of the aquatic community in its tank, and nutrient assimilation by the leaves. Based on nitrogen and nitrogen stable isotope measurements of the A. mertensii leaves, the leaf litter inside of the tank and the root-embedded carton nest, we discuss the potential sources of available nitrogen for the plant based on the ant partner. We demonstrate the existence of a complex ant-plant interaction that subsequently affects the biodiversity of a broader range of organisms that are themselves likely to influence nutrient assimilation by the A. mertensii leaves in a kind of plant-invertebrate-plant feedback loop.
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Notes Potential sources of nitrogen in an ant-garden tank-bromeliad Approved no
Call Number EcoFoG @ eric.marcon @ 12 Serial 186
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Author Gonzalez, M.A.; Baraloto, C.; Engel, J.; Mori, S.A.; Petronelli, P.; Riera, B.; Roger, A.; Thebaud, C.; Chave, J.
Title Identification of Amazonian Trees with DNA Barcodes Type Journal Article
Year 2009 Publication PLoS One Abbreviated Journal PLoS One
Volume 4 Issue 10 Pages e7483
Keywords
Abstract Background: Large-scale plant diversity inventories are critical to develop informed conservation strategies. However, the workload required for classic taxonomic surveys remains high and is particularly problematic for megadiverse tropical forests. Methodology/Principal Findings: Based on a comprehensive census of all trees in two hectares of a tropical forest in French Guiana, we examined whether plant DNA barcoding could contribute to increasing the quality and the pace of tropical plant biodiversity surveys. Of the eight plant DNA markers we tested (rbcLa, rpoC1, rpoB, matK, ycf5, trnL, psbA-trnH, ITS), matK and ITS had a low rate of sequencing success. More critically, none of the plastid markers achieved a rate of correct plant identification greater than 70%, either alone or combined. The performance of all barcoding markers was noticeably low in few species-rich clades, such as the Laureae, and the Sapotaceae. A field test of the approach enabled us to detect 130 molecular operational taxonomic units in a sample of 252 juvenile trees. Including molecular markers increased the identification rate of juveniles from 72% (morphology alone) to 96% (morphology and molecular) of the individuals assigned to a known tree taxon. Conclusion/Significance: We conclude that while DNA barcoding is an invaluable tool for detecting errors in identifications and for identifying plants at juvenile stages, its limited ability to identify collections will constrain the practical implementation of DNA-based tropical plant biodiversity programs.
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Corporate Author Thesis
Publisher PUBLIC LIBRARY SCIENCE Place of Publication Editor
Language Summary Language Original Title
Series Editor (up) Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1932-6203 ISBN Medium
Area Expedition Conference
Notes ISI:000270880700009 Approved no
Call Number EcoFoG @ eric.marcon @ Serial 189
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Author Coste, S.; Roggy, J.C.; Imbert, P.; Born, C.; Bonal, D.; Dreyer, E.
Title Leaf photosynthetic traits of 14 tropical rain forest species in relation to leaf nitrogen concentration and shade tolerance Type Journal Article
Year 2005 Publication Tree Physiology Abbreviated Journal Tree Physiol.
Volume 25 Issue 9 Pages 1127-1137
Keywords functional diversity; leaf carbon; leaf nitrogen; nitrogen-use efficiency; photosynthetic capacity; tropical rain forest
Abstract Variability of leaf traits related to photosynthesis was assessed in seedlings from 14 tree species growing in the tropical rain forest of French Guiana. Leaf photosynthetic capacity (maximum rate of carboxylation and maximum rate of electron transport) was estimated by fitting a biochemical model of photosynthesis to response curves of net CO2 assimilation rate versus intercellular CO2 mole fraction. Leaf morphology described by leaf mass per unit leaf area (LMA), density and thickness, as well as area- and mass-based nitrogen (N) and carbon (C) concentrations, were recorded on the same leaves. Large interspecific variability was detected in photosynthetic capacity as well as in leaf structure and leaf N and C concentrations. No correlation was found between leaf thickness and density. The correlations between area- and mass-based leaf N concentration and photosynthetic capacity were poor. Conversely, the species differed greatly in relative N allocation to carboxylation and bioenergetics. Principal component analysis (PCA) revealed that, of the recorded traits, only the computed fraction of total leaf N invested in photosynthesis was tightly correlated to photosynthetic capacity. We also used PCA to test to what extent species with similar shade tolerances displayed converging leaf traits related to photosynthesis. No clear-cut ranking could be detected among the shade-tolerant groups, as confirmed by a one-way ANOVA. We conclude that the large interspecific diversity in photosynthetic capacity was mostly explained by differences in the relative allocation of N to photosynthesis and not by leaf N concentration, and that leaf traits related to photosynthetic capacity did not discriminate shade-tolerance ranking of these tropical tree species.
Address CNRS Ecol Forets Guyane, INRA, ENGREF,CIRAD, Unite Mixte Rech, Kourou 97387, French Guiana, Email: roggy.j@cirad.fr
Corporate Author Thesis
Publisher HERON PUBLISHING Place of Publication Editor
Language Summary Language Original Title
Series Editor (up) Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0829-318X ISBN Medium
Area Expedition Conference
Notes ISI:000231555200005 Approved no
Call Number EcoFoG @ eric.marcon @ Serial 230
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Author Foucaud, J.; Orivel, J.; Fournier, D.; Delabie, J.H.C.; Loiseau, A.; Le Breton, J.; Cerdan, P.; Estoup, A.
Title Reproductive system, social organization, human disturbance and ecological dominance in native populations of the little fire ant, Wasmannia auropunctata Type Journal Article
Year 2009 Publication Molecular Ecology Abbreviated Journal Mol. Ecol.
Volume 18 Issue 24 Pages 5059-5073
Keywords biological invasion; clonality; human disturbance; parthenogenesis; social organization; Wasmannia auropunctata
Abstract The invasive ant species Wasmannia auropunctata displays both ecologically dominant and non-dominant populations within its native range. Three factors could theoretically explain the ecological dominance of some native populations of W. auropunctata: (i) its clonal reproductive system, through demographic and/or adaptive advantages; (ii) its unicolonial social organization, through lower intraspecific and efficient interspecific competition; (iii) the human disturbance of its native range, through the modification of biotic and abiotic environmental conditions. We used microsatellite markers and behavioural tests to uncover the reproductive modes and social organization of dominant and non-dominant native populations in natural and human-modified habitats. Microsatellite and mtDNA data indicated that dominant and non-dominant native populations (supercolonies as determined by aggression tests) of W. auropunctata did not belong to different evolutionary units. We found that the reproductive system and the social organization are neither necessary nor sufficient to explain W. auropunctata ecological dominance. Dominance rather seems to be set off by unknown ecological factors altered by human activities, as all dominant populations were recorded in human-modified habitats. The clonal reproductive system found in some populations of W. auropunctata may however indirectly contribute to its ecological dominance by allowing the species to expand its environmental niche, through the fixation over time of specific combinations of divergent male and female genotypes. Unicoloniality may rather promote the range expansion of already dominant populations than actually trigger ecological dominance. The W. auropunctata model illustrates the strong impact of human disturbance on species' ecological features and the adaptive potential of clonal reproductive systems.
Address [Foucaud, Julien; Fournier, Denis; Loiseau, Anne; Estoup, Arnaud] Montpellier SupAgro, Cirad, IRD, INRA,UMR CBGP, F-34988 Montferrier Sur Lez, France, Email: julien.foucaud@legs.cnrs-gif.fr
Corporate Author Thesis
Publisher WILEY-BLACKWELL PUBLISHING, INC Place of Publication Editor
Language Summary Language Original Title
Series Editor (up) Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0962-1083 ISBN Medium
Area Expedition Conference
Notes ISI:000272452700009 Approved no
Call Number EcoFoG @ eric.marcon @ Serial 191
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Author Szilagyi, A.; Scheuring, I.; Edwards, D.P.; Orivel, J.; Yu, D.W.
Title The evolution of intermediate castration virulence and ant coexistence in a spatially structured environment Type Journal Article
Year 2009 Publication Ecology Letters Abbreviated Journal Ecol. Lett.
Volume 12 Issue 12 Pages 1306-1316
Keywords Cooperation; evolution of virulence; host-pathogen; mutualism; myrmecophyte; parasite; rock-paper-scissors; spatial games; tolerance; trade-off
Abstract Theory suggests that spatial structuring should select for intermediate levels of virulence in parasites, but empirical tests are rare and have never been conducted with castration (sterilizing) parasites. To test this theory in a natural landscape, we construct a spatially explicit model of the symbiosis between the ant-plant Cordia nodosa and its two, protecting ant symbionts, Allomerus and Azteca. Allomerus is also a castration parasite, preventing fruiting to increase colony fecundity. Limiting the dispersal of Allomerus and host plant selects for intermediate castration virulence. Increasing the frequency of the mutualist, Azteca, selects for higher castration virulence in Allomerus, because seeds from Azteca-inhabited plants are a public good that Allomerus exploits. These results are consistent with field observations and, to our knowledge, provide the first empirical evidence supporting the hypothesis that spatial structure can reduce castration virulence and the first such evidence in a natural landscape for either mortality or castration virulence.
Address [Edwards, David P.; Yu, Douglas W.] Univ E Anglia, Sch Biol Sci, Norwich NR4 7TJ, Norfolk, England, Email: dougwyu@gmail.com
Corporate Author Thesis
Publisher WILEY-BLACKWELL PUBLISHING, INC Place of Publication Editor
Language Summary Language Original Title
Series Editor (up) Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1461-023X ISBN Medium
Area Expedition Conference
Notes ISI:000271631500006 Approved no
Call Number EcoFoG @ eric.marcon @ Serial 192
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Author Cohen, M.C.L.; Behling, H.; Lara, R.J.; Smith, C.B.; Matos, H.R.S.; Vedel, V.
Title Impact of sea-level and climatic changes on the Amazon coastal wetlands during the late Holocene Type Journal Article
Year 2009 Publication Vegetation History and Archaeobotany Abbreviated Journal Veg. Hist. Archaeobot.
Volume 18 Issue 6 Pages 425-439
Keywords Mangrove; Marajo Island; Pollen analysis; Sea-level
Abstract Wetland dynamics in northern Brazil during the Holocene were studied by pollen analysis and AMS radiocarbon dating of three cores. Near the Amazon mouth region, covered mainly by primary Amazon coastal forest and herbaceous vegetation, the pollen record indicates the dominance of mangroves between 4800 and 1100 cal yr B.P. A contraction of the mangrove area and an expansion of herbaceous and fern vegetation occurred between 1100 and 750 cal yr B.P. The period between 750 and 200 cal yr B.P. is characterized by an expansion of mangrove and a decrease in herbaceous and fern vegetation. This trend continued until the present. On Atalaia Island, the sediment core indicates a period with poor pollen preservation between 830 and 630 cal yr B.P. Between 630 and 330 cal yr B.P., mangroves expanded. Later, up to 45 cal yr B.P., the mangrove area decreased and the herbaceous vegetation expanded. During the last hundred years, the relative sea-level rise most probably favored the mangrove expansion as far as the topographically highest sector on this island, while the herbaceous vegetation decreased. The pollen data from Agua Preta Lake indicate dry conditions, as reflected by the poor pollen preservation between 390 and 240 cal yr B.P. Between 240 and 60 cal yr B.P., restinga and Amazon coastal forest with palms dominated this region. For the last 120 years, the record indicates an expansion of the mangrove area. However, recent confinement of mangrove development to the topographically highest area, and the loss of mangrove areas on the lowest surfaces have led to a net loss of mangrove coverage during the last decades.
Address [Lisboa Cohen, Marcelo Cancela; Smith, Clarisse Beltrao; Soares Matos, Hellen Rosy] Fed Univ Para, Postgrad Program Geol & Geochem, Lab Coastal Dynam, BR-66077530 Belem, PA, Brazil, Email: mcohen@ufpa.br
Corporate Author Thesis
Publisher SPRINGER Place of Publication Editor
Language Summary Language Original Title
Series Editor (up) Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0939-6314 ISBN Medium
Area Expedition Conference
Notes ISI:000271191800001 Approved no
Call Number EcoFoG @ eric.marcon @ Serial 193
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Author Campillo, F.; Rossi, V.
Title Convolution Particle Filter for Parameter Estimation in General State-Space Models Type Journal Article
Year 2009 Publication IEEE Transactions on Aerospace and Electronic Systems Abbreviated Journal IEEE Trans. Aerosp. Electron. Syst.
Volume 45 Issue 3 Pages 1063-1072
Keywords
Abstract The state-space modeling of partially observed dynamical systems generally requires estimates of unknown parameters. The dynamic state vector together with the static parameter vector can be considered as an augmented state vector. Classical filtering methods, such as the extended Kalman filter (EKF) and the bootstrap particle filter (PF), fail to estimate the augmented state vector. For these classical filters to handle the augmented state vector, a dynamic noise term should be artificially added to the parameter components or to the deterministic component of the dynamical system. However, this approach degrades the estimation performance of the filters. We propose a variant of the PF based on convolution kernel approximation techniques. This approach is tested on a simulated case study.
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Corporate Author Thesis
Publisher IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC Place of Publication Editor
Language Summary Language Original Title
Series Editor (up) Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0018-9251 ISBN Medium
Area Expedition Conference
Notes ISI:000270225500017 Approved no
Call Number EcoFoG @ eric.marcon @ Serial 194
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Author Seymour, R.S.; Gibernau, M.; Pirintsos, S.A.
Title Thermogenesis of three species of Arum from Crete Type Journal Article
Year 2009 Publication Plant Cell and Environment Abbreviated Journal Plant Cell Environ.
Volume 32 Issue 10 Pages 1467-1476
Keywords Araceae; arum lily; inflorescence; pollination; temperature regulation
Abstract Inflorescences of arum lilies have a three-part spadix with a scent-producing, sterile appendix above two bands of fertile male and female florets. The appendix and male florets are thermogenic, but with different temporal patterns. Heat-production was measured in Arum concinnatum, A. creticum and A. idaeum. The male florets of A. concinnatum showed a 3 d continuous episode of thermogenesis with three waves, and the appendix warmed in a single, 6 h episode. Maximum fresh-mass-specific CO2 production rate was 0.17 μmol s(-1) g(-1) to achieve a 10.9 degrees C temperature elevation by the appendix, and 0.92 μmol s(-1) g(-1) to achieve a 4.8 degrees C elevation by male florets. Reversible, physiological temperature regulation was not evident in either tissue. Respiration increased with tissue temperatures with Q(10) values of 1.8-3.9, rather than less than 1.0 as occurs in thermoregulatory flowers. Experimental step changes in temperature of appendix and male floret tissues also failed to show thermoregulatory responses. The patterns of thermogenesis therefore appear to be fixed by the temporal sequence of blooming. Thermogenesis in the alpine species, A. creticum and A. idaeum, was significantly lower than in the lowland A. concinnatum, possibly related to difficulty in raising floral temperature in their cold and windy habitat.
Address [Seymour, Roger S.] Univ Adelaide, Adelaide, SA 5005, Australia, Email: roger.seymour@adelaide.edu.au
Corporate Author Thesis
Publisher WILEY-BLACKWELL PUBLISHING, INC Place of Publication Editor
Language Summary Language Original Title
Series Editor (up) Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0140-7791 ISBN Medium
Area Expedition Conference
Notes ISI:000269592300016 Approved no
Call Number EcoFoG @ eric.marcon @ Serial 195
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Author Gloor, M.; Phillips, O.L.; Lloyd, J.J.; Lewis, S.L.; Malhi, Y.; Baker, T.R.; Lopez-Gonzalez, G.; Peacock, J.; Almeida, S.; de Oliveira, A.C.A.; Alvarez, E.; Amaral, I.; Arroyo, L.; Aymard, G.; Banki, O.; Blanc, L.; Bonal, D.; Brando, P.; Chao, K.J.; Chave, J.; Davila, N.; Erwin, T.; Silva, J.; Di Fiore, A.; Feldpausch, T.R.; Freitas, A.; Herrera, R.; Higuchi, N.; Honorio, E.; Jimenez, E.; Killeen, T.; Laurance, W.; Mendoza, C.; Monteagudo, A.; Andrade, A.; Neill, D.; Nepstad, D.; Vargas, P.N.; Penuela, M.C.; Cruz, A.P.; Prieto, A.; Pitman, N.; Quesada, C.; Salomao, R.; Silveira, M.; Schwarz, M.; Stropp, J.; Ramirez, F.; Ramirez, H.; Rudas, A.; ter Steege, H.; Silva, N.; Torres, A.; Terborgh, J.; Vasquez, R.; van der Heijden, G.
Title Does the disturbance hypothesis explain the biomass increase in basin-wide Amazon forest plot data? Type Journal Article
Year 2009 Publication Global Change Biology Abbreviated Journal Glob. Change Biol.
Volume 15 Issue 10 Pages 2418-2430
Keywords Amazon rainforest; carbon sink; disturbance; mortality; power law
Abstract Positive aboveground biomass trends have been reported from old-growth forests across the Amazon basin and hypothesized to reflect a large-scale response to exterior forcing. The result could, however, be an artefact due to a sampling bias induced by the nature of forest growth dynamics. Here, we characterize statistically the disturbance process in Amazon old-growth forests as recorded in 135 forest plots of the RAINFOR network up to 2006, and other independent research programmes, and explore the consequences of sampling artefacts using a data-based stochastic simulator. Over the observed range of annual aboveground biomass losses, standard statistical tests show that the distribution of biomass losses through mortality follow an exponential or near-identical Weibull probability distribution and not a power law as assumed by others. The simulator was parameterized using both an exponential disturbance probability distribution as well as a mixed exponential-power law distribution to account for potential large-scale blowdown events. In both cases, sampling biases turn out to be too small to explain the gains detected by the extended RAINFOR plot network. This result lends further support to the notion that currently observed biomass gains for intact forests across the Amazon are actually occurring over large scales at the current time, presumably as a response to climate change.
Address [Gloor, M.; Phillips, O. L.; Lloyd, J. J.; Lewis, S. L.; Baker, T. R.; Lopez-Gonzalez, G.; Peacock, J.; Feldpausch, T. R.] Univ Leeds, Sch Geog, Leeds LS2 9JT, W Yorkshire, England, Email: eugloor@googlemail.com
Corporate Author Thesis
Publisher WILEY-BLACKWELL PUBLISHING, INC Place of Publication Editor
Language Summary Language Original Title
Series Editor (up) Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1354-1013 ISBN Medium
Area Expedition Conference
Notes ISI:000269577800006 Approved no
Call Number EcoFoG @ eric.marcon @ Serial 196
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Author Campillo, F.; Rakotozafy, R.; Rossi, V.
Title Parallel and interacting Markov chain Monte Carlo algorithm Type Journal Article
Year 2009 Publication Mathematics and Computers in Simulation Abbreviated Journal Math. Comput. Simul.
Volume 79 Issue 12 Pages 3424-3433
Keywords Markov chain Monte Carlo method; Interacting chains; Hidden Markov model
Abstract In many situations it is important to be able to propose N independent realizations of a given distribution law. We propose a strategy for making N parallel Monte Carlo Markov chains (MCMC) interact in order to get an approximation of an independent N-sample of a given target law. In this method each individual chain proposes candidates for all other chains. We prove that the set of interacting chains is itself a MCMC method for the product of N target measures. Compared to independent parallel chains this method is more time consuming. but we show through examples that it possesses many advantages. This approach is applied to a biomass evolution model. (C) 2009 IMACS. Published by Elsevier B.V. All rights reserved.
Address [Rossi, Vivien] CIRAD, Res Unit, Montpellier, France, Email: Fabien.Campillo@inria.fr
Corporate Author Thesis
Publisher ELSEVIER SCIENCE BV Place of Publication Editor
Language Summary Language Original Title
Series Editor (up) Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0378-4754 ISBN Medium
Area Expedition Conference
Notes ISI:000269289100006 Approved no
Call Number EcoFoG @ eric.marcon @ Serial 197
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