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Author Dezerald, O.; Leroy, C.; Corbara, B.; Dejean, A.; Talaga, S.; Céréghino, R. doi  openurl
  Title (down) Environmental drivers of invertebrate population dynamics in Neotropical tank bromeliads Type Journal Article
  Year 2017 Publication Freshwater Biology Abbreviated Journal Freshw Biol  
  Volume 62 Issue 2 Pages 229-242  
  Keywords food webs; freshwater invertebrates; growth rate; life history; rainforest  
  Abstract Tank bromeliads form a conspicuous, yet neglected freshwater habitat in Neotropical forests. Recent studies driven by interests in medical entomology, fundamental aspects of bromeliad ecology and experimental research on food webs have, however, prompted increasing interest in bromeliad aquatic ecosystems. As yet, there is nothing in the literature about the life histories and environmental drivers of invertebrate population dynamics in tank bromeliads.

Based on fortnightly samples taken over one year, size frequency plots and individual dry masses allowed us to establish the life cycles and growth rates of the dominant aquatic invertebrates in a common bromeliad species of French Guiana. Linear mixed-effect models and Mantel tests were used to predict changes in density, biomass, and growth rates in relation to temperature, rainfall, humidity and detrital resources.

Annual variations in invertebrate densities and biomasses could be described according to three types of distribution: unimodal, bimodal or almost constant. Despite seasonal variations, precipitation, temperature, relative humidity and detritus concentration accounted significantly for changes in density and biomass, but we found no significant responses in growth rates of most invertebrate species. Species rather displayed non-seasonal life cycles with overlapping cohorts throughout the year. There was also a trend for delayed abundance peaks among congeneric species sharing similar functional traits, suggesting temporal partitioning of available resources.

Beyond novel knowledge, quantitative information on life histories is important to predict food-web dynamics under the influence of external forcing and self-organisation. Our results suggest that changes in species distribution that will affect population dynamics through biotic interactions in space and/or time could have greater effects on food webs and ecosystem functioning than changes in environmental factors per se.
 
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  ISSN 1365-2427 ISBN Medium  
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  Call Number EcoFoG @ webmaster @ Serial 716  
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Author Talaga, S.; Petitclerc, F.; Carrias, J.-F.; Dezerald, O.; Leroy, C.; Céréghino, R.; Dejean, A. url  doi
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  Title (down) Environmental drivers of community diversity in a neotropical urban landscape: a multi-scale analysis Type Journal Article
  Year 2017 Publication Landscape Ecology Abbreviated Journal Landscape Ecology  
  Volume 32 Issue 9 Pages 1805-1818  
  Keywords Aquatic metacommunity; Landscape ecology; Mosquitoes; Neotropics; Scale dependency; Tank bromeliads; Urban ecology  
  Abstract Context: Many aquatic communities are linked by the aerial dispersal of multiple, interacting species and are thus structured by processes occurring in both the aquatic and terrestrial compartments of the ecosystem. Objectives: To evaluate the environmental factors shaping the aquatic macroinvertebrate communities associated with tank bromeliads in an urban landscape. Methods: Thirty-two bromeliads were georeferenced to assess the spatial distribution of the aquatic meta-habitat in one city. The relative influence of the aquatic and terrestrial habitats on the structure of macroinvertebrate communities was analyzed at four spatial scales (radius = 10, 30, 50, and 70 m) using redundancy analyses. Results: We sorted 18,352 aquatic macroinvertebrates into 29 taxa. Water volume and the amount of organic matter explained a significant part of the taxa variance, regardless of spatial scale. The remaining variance was explained by the meta-habitat size (i.e., the water volume for all of the bromeliads within a given surface area), the distance to the nearest building at small scales, and the surface area of buildings plus ground cover at larger scales. At small scales, the meta-habitat size influenced the two most frequent mosquito species in opposite ways, suggesting spatial competition and coexistence. Greater vegetation cover favored the presence of a top predator. Conclusions: The size of the meta-habitat and urban landscape characteristics influence the structure of aquatic communities in tank bromeliads, including mosquito larval abundance. Modifications to this landscape will affect both the terrestrial and aquatic compartments of the urban ecosystem, offering prospects for mosquito management during urban planning. © 2017, Springer Science+Business Media B.V.  
  Address IRD; UMR AMAP (botAnique et Modélisation de l’Architecture des Plantes et des végétations), Boulevard de la Lironde, TA A‐51/PS2, Montpellier Cedex 5, France  
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  Notes Export Date: 18 December 2017 Approved no  
  Call Number EcoFoG @ webmaster @ Serial 777  
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Author Dezerald, O.; Talaga, S.; Leroy, C.; Carrias, J.-F.; Corbara, B.; Dejean, A.; Céréghino, R. url  doi
openurl 
  Title (down) Environmental determinants of macroinvertebrate diversity in small water bodies: Insights from tank-bromeliads Type Journal Article
  Year 2014 Publication Hydrobiologia Abbreviated Journal Hydrobiologia  
  Volume 723 Issue 1 Pages 77-86  
  Keywords Freshwater biodiversity; Linear mixed effect modelling; Microcosms; Phytotelmata; Ponds  
  Abstract The interlocking leaves of tank-forming bromeliads (Bromeliaceae) collect rainwater and detritus, thus creating a freshwater habitat for specialized organisms. Their abundance and the possibility of quantifying communities with accuracy give us unparalleled insight into how changes in local to regional environments influence community diversity in small water bodies. We sampled 365 bromeliads (365 invertebrate communities) along a southeastern to northwestern range in French Guiana. Geographic locality determined the species pool for bromeliad invertebrates, and local environments determined the abundance patterns through the selection of traits that are best adapted to the bromeliad habitats. Patterns in community structure mostly emerged from patterns of predator species occurrence and abundance across local-regional environments, while the set of detritivores remained constant. Water volume had a strong positive correlation with invertebrate diversity, making it a biologically relevant measure of the pools' carrying capacity. The significant effects of incoming detritus and incident light show that changes in local environments (e.g., the conversion of forest to cropping systems) strongly influence freshwater communities. Because changes in local environments do not affect detritivores and predators equally, one may expect functional shifts as sets of invertebrates with particular traits are replaced or complemented by other sets with different traits. © 2013 Springer Science+Business Media Dordrecht.  
  Address CNRS, EcoLab (UMR-CNRS 5245), 118 Route de Narbonne, 31062 Toulouse, France  
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  ISSN 00188158 (Issn) ISBN Medium  
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  Call Number EcoFoG @ webmaster @ Serial 517  
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Author Goulamoussene, Y.; Bedeau, C.; Descroix, L.; Linguet, L.; Herault, B. pdf  url
doi  openurl
  Title (down) Environmental control of natural gap size distribution in tropical forests Type Journal Article
  Year 2017 Publication Biogeosciences Abbreviated Journal Biogeosciences  
  Volume 14 Issue 2 Pages 353-364  
  Keywords  
  Abstract Natural disturbances are the dominant form of forest regeneration and dynamics in unmanaged tropical forests. Monitoring the size distribution of treefall gaps is important to better understand and predict the carbon budget in response to land use and other global changes. In this study, we model the size frequency distribution of natural canopy gaps with a discrete power law distribution. We use a Bayesian framework to introduce and test, using Monte Carlo Markov chain and Kuo-Mallick algorithms, the effect of local physical environment on gap size distribution. We apply our methodological framework to an original light detecting and ranging dataset in which natural forest gaps were delineated over 30 000 ha of unmanaged forest. We highlight strong links between gap size distribution and environment, primarily hydrological conditions and topography, with large gaps being more frequent on floodplains and in wind-exposed areas. In the future, we plan to apply our methodological framework on a larger scale using satellite data. Additionally, although gap size distribution variation is clearly under environmental control, variation in gap size distribution in time should be tested against climate variability. © Author(s) 2017.  
  Address Cirad, UMR EcoFoG, AgroParisTech, CNRS, Inra, Univ Antilles, Univ Guyane, Kourou, French Guiana  
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  Notes Export Date: 7 February 2017 Approved no  
  Call Number EcoFoG @ webmaster @ Serial 729  
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Author Marcon, E. url  doi
openurl 
  Title (down) Entropy as a common measure of biodiversity and the spatial structure of economic activity Type Journal Article
  Year 2019 Publication Revue Economique Abbreviated Journal Rev. Econ.  
  Volume 70 Issue 3 Pages 305-326  
  Keywords Diversity; Economic geography; Spatial concentration; Specialization  
  Abstract Measures of spatial concentration and specialization in economics are similar to those of biodiversity and ubiquity of species in ecology. Entropy is the fundamental tool that originated in statistical physics and information theory. The definition of number equivalents or effective numbers, that is the number of types in an ideal, simplified distribution, is introduced along with the partitioning of the joint diversity of a bi-dimensional distribution into absolute and relative concentration or specialization and replication. The whole framework is theoretically robust and allows measuring the spatial structure of a discrete space.  
  Address AgroParisTech, UMR Écologie des forêts de Guyane, CNRS, Cirad, INRA, Université des Antilles, Université de Guyane, Campus Agronomique, BP 701, Kourou, 97310, French Guiana  
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  Publisher Presses de Sciences Po Place of Publication Editor  
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  Series Volume Series Issue Edition  
  ISSN 00352764 (Issn) ISBN Medium  
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  Notes Approved no  
  Call Number EcoFoG @ webmaster @ Serial 912  
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Author Marcon, E.; Herault, B. pdf  url
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  Title (down) entropart: An R package to measure and partition diversity Type Journal Article
  Year 2015 Publication Journal of Statistical Software Abbreviated Journal Journal of Statistical Software  
  Volume 67 Issue 8 Pages 1-26  
  Keywords Biodiversity; Entropy; Partitioning  
  Abstract entropart is a package for R designed to estimate diversity based on HCDT entropy or similarity-based entropy. It allows calculating species-neutral, phylogenetic and functional entropy and diversity, partitioning them and correcting them for estimation bias. © 2015, American Statistical Association. All rights reserved.  
  Address Cirad, Campus agronomique, BP 316, Kourou, French Guiana  
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  Notes Export Date: 22 October 2015 Approved no  
  Call Number EcoFoG @ webmaster @ Serial 633  
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Author Chevalier, M.; Robert, F.; Amusant, N.; Traisnel, M.; Roos, C.; Lebrini, M. url  openurl
  Title (down) Enhanced corrosion resistance of mild steel in 1 M hydrochloric acid solution by alkaloids extract from Aniba rosaeodora plant: Electrochemical, phytochemical and XPS studies Type Journal Article
  Year 2014 Publication Electrochimica Acta Abbreviated Journal Electrochim Acta  
  Volume 131 Issue Pages 96-105  
  Keywords Acidic media; Adsorption-XPS; Aniba rosaeodora extract; Anibine; C38 steel; Corrosion inhibitor  
  Abstract The present report continues to focus on the broadening application of plant extracts for metallic corrosion control and reports on the inhibiting effect of the Aniba rosaeodora alkaloidic extract on the corrosion of C38 steel in 1 M hydrochloric acid. Potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) techniques were applied to study the metal corrosion behavior in the absence and presence of inhibitor. Studies on the phytochemical constituents were established to determine the active(s) molecule(s). XPS was also carried out to establish the mechanism of corrosion inhibition of the active molecule of C38 steel in acid solution. The inhibitor extract acted as an efficient corrosion inhibitor in 1 M HCl. The experimental data obtained from EIS method show a frequency distribution and therefore a modelling element with frequency dispersion behaviour, a constant phase element (CPEα, Q) has been used. Graphical methods are illustrated by synthetic data to determine the parameter of CPE (α, Q). Polarization studies showed that the Aniba rosaeodora alkaloidic extract was a mixed-type inhibitor and its inhibition efficiency increased with the inhibitor concentration. Studies on the phytochemical constituents of the total alkaloids extract shows that it contains the anibine as the major alkaloid. The results obtained from the electrochemical study have clearly showed that the inhibition efficiency of the total extract was due to the presence of anibine. The XPS studies showed the formation of inhibitor layer containing the Aniba rosaeodora alkaloidic extract and the anibine molecules. © 2014 Elsevier Ltd. All rights reserved.  
  Address Unité Matériaux et Transformations CNRS UMR 8207, Université Lille 1, École Nationale Supérieure de Chimie de Lille, Avenue Dimitri Mendeleïev-Bât. C7a BP 90108, 59652 Villeneuve d'Ascq, France  
  Corporate Author Thesis  
  Publisher Elsevier Ltd Place of Publication Editor  
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  ISSN 00134686 (Issn) ISBN Medium  
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  Notes Export Date: 10 June 2014; Coden: Elcaa; Correspondence Address: Lebrini, M.; Laboratoire Matériaux et Molécules en Milieux Amazonien, UAG-UMR ECOFOG Campus Troubiran, Route de Baduel, 97337 Cayenne, French Guiana; email: mounim.lebrini@guyane.univ-ag.fr Approved no  
  Call Number EcoFoG @ webmaster @ Serial 545  
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Author Salvin, P.; Ondel, O.; Roos, C.; Robert, F. doi  openurl
  Title (down) Energy harvest with mangrove benthic microbial fuel cells Type Journal Article
  Year 2015 Publication International Journal of Energy Research Abbreviated Journal Int J Energy Res  
  Volume 39 Issue 4 Pages 543-556  
  Keywords Balancing circuit; Benthic microbial fuel cell; Efficiency; Energy harvesting  
  Abstract Benthic microbial fuel cells (BMFCs) are continuous electricity generators using electroactive microorganisms and organic matter from aquatic environment, respectively, as catalysts and substrate. In this paper, first a low-cost PVC-made structure is constructed to harvest electricity from mangrove environment located in French Guiana. An in situ BMFC has given power density of 30mW/m2 of the anodic surface area. This performance has been confirmed by experience in laboratory where inter-electrode distance and electrode surface area appeared to be power increasing factors. However, the output power of one BMFC is not used to supply real devices such as autonomous sensors. Second, to meet this expectation, in parallel and in series associations were considered. These associations were made in order to increase the output voltage and consequently the power, to reach levels that can supply small sensors (about 3V). Finally, to improve the performance of the series association and to avoid the voltage reversal phenomenon, a voltage balancing circuit was simulated and added to the series connections. With balancing method, the cell voltage of BMFCs can be equalized, and the performances can be improved. This allows an optimal energy harvesting and a better global efficiency of the set.  
  Address Université de Lyon, F-69622, Lyon, France, Université Lyon 1, Villeurbanne; CNRS, UMR 5005, Laboratoire Ampère, 43, Boulevard du 11 Novembre 1918Villeurbanne, France  
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  Notes Export Date: 17 March 2015 Approved no  
  Call Number EcoFoG @ webmaster @ Serial 586  
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Author Seymour, R.S.; White, C.R.; Gibernau, M. openurl 
  Title (down) Endothermy of dynastine scarab beetles (Cyclocephala colasi) associated with pollination biology of a thermogenic arum lily (Philodendron solimoesense) Type Journal Article
  Year 2009 Publication Journal of Experimental Biology Abbreviated Journal J. Exp. Biol.  
  Volume 212 Issue 18 Pages 2960-2968  
  Keywords beetle; endothermy; pollination biology; Cyclocephala; Philodendron  
  Abstract Cyclocephala colasi beetles are facultative endotherms that spend most of their adult lives inside the inflorescences of Philodendron solimoesense, where ambient temperature (T-a) averages about 28 degrees C due to floral thermogenesis. Measurements of respiration within a range of T-a showed that active beetles became spontaneously endothermic at T-a below 28 degrees C but were rarely endothermic above it. There was no evidence of endothermy within the inflorescences, indicating that activities in the floral chamber can occur without the high energy expense of endothermy. Bouts of endothermy occurred at lower T-a in respirometer chambers mainly in the evening, when the insects normally fly from one inflorescence to another, and during the night, when they normally eat and mate within the inflorescence. Patterns of endothermy in individual episodes were studied in non-flying beetles with respirometry and infrared thermal imaging. Heat was generated in the thorax by oscillatory waves of respiration that were coupled with thoracic temperature (T-th) increases. Stationary beetles could regulate T-th at about 33 degrees C independently of T-a between 16 and 29 degrees C. At T-a=20 degrees C, this represents a 116-fold increase in metabolic rate over resting, ectothermic values. Endothermy was clearly a requirement for flight, and beetles departing inflorescences warmed to about 30 degrees C before take-off. During flight, T-th was dependent on T-a, decreasing from 37 to 28 degrees C at T-a of 37 to 20 degrees C, respectively. The lowest T-a at which flight could occur was about 20 degrees C. Thermal conductance of stationary, endothermic beetles increased at higher metabolic rates, probably because of increased ventilatory heat loss.  
  Address [Seymour, Roger S.] Univ Adelaide, Sch Earth & Environm Sci, Adelaide, SA 5005, Australia, Email: roger.seymour@adelaide.edu.au  
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  Publisher COMPANY OF BIOLOGISTS LTD Place of Publication Editor  
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  ISSN 0022-0949 ISBN Medium  
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  Notes ISI:000269383500014 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 198  
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Author Urbina, I.; Grau, O.; Sardans, J.; Ninot, J.M.; Peñuelas, J. doi  openurl
  Title (down) Encroachment of shrubs into subalpine grasslands in the Pyrenees changes the plant-soil stoichiometry spectrum Type Journal Article
  Year 2020 Publication Plant and Soil Abbreviated Journal Plant Soil  
  Volume 448 Issue 1-2 Pages 37-53  
  Keywords Nutrient stocks; Plant strategy; Plant-soil stoichiometry; Shrub encroachment; Subalpine grassland succession; aboveground biomass; biogeochemical cycle; carbon sequestration; ectomycorrhiza; fungus; grass; nitrogen; nutrient uptake; shrub; soil-vegetation interaction; stoichiometry; subalpine environment; succession; Europe; Pyrenees; Fungi  
  Abstract Aims: Shrub encroachment has been reported over a large proportion of the subalpine grasslands across Europe and is expected to have an important impact on the biogeochemical cycle of these ecosystems. We investigated the stoichiometric changes in the plant-soil system along the succession (e.g. increase in encroachment from unencroached grassland to mature shrubland) at two contrasting sites in the Pyrenees. Methods: We analyzed the chemical composition (C, N,15N, P, K, Ca, Mg and Fe) in the soil and in the aboveground plant compartments (leaves, leaf-litter and stems) of the main herbaceous species and shrubs at three contrasting stages of the succession: unencroached grassland, young shrubland and mature shrubland. Results: The plant-soil stoichiometry spectrum differed between the successional stages. Shrub encroachment generally increased the concentration of C and Ca and the C:N ratio and often reduced to concentrations of N, P and K in the leaves and leaf-litter, while several soil nutrient concentrations (N, P, K Ca and Mg) decreased. The stocks of C, N, P, Ca, and Mg in the total aboveground biomass increased with encroachment. Conclusions: Shrub encroachment favored the dominance of long-lived species with low concentrations of N and P in the plant-soil compartments, high C:nutrient ratios in the aboveground biomass and increase the uptake of N through ericoid or ectomycorrhizal fungi. We highlight the role of shrubs in the sequestration of C and nutrients through the allocation to the aboveground biomass. The changes in plant-soil elemental composition and stocks suggest a slowdown of the biogeochemical cycles in the subalpine mountain areas where shrub encroachment occurred. © 2020, Springer Nature Switzerland AG.  
  Address Biodiversity Research Institute (IRBio) and Department of Evolutionary Biology, Ecology and Environmental Sciences, University of Barcelona, Barcelona, Catalonia, Spain  
  Corporate Author Thesis  
  Publisher Springer Place of Publication Editor  
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  ISSN 0032079x (Issn) ISBN Medium  
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  Notes Approved no  
  Call Number EcoFoG @ webmaster @ Serial 983  
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