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Author Longo, M.; Saatchi, S.; Keller, M.; Bowman, K.; Ferraz, A.; Moorcroft, P.R.; Morton, D.C.; Bonal, D.; Brando, P.; Burban, B.; Derroire, G.; dos-Santos, M.N.; Meyer, V.; Saleska, S.; Trumbore, S.; Vincent, G. doi  openurl
  Title Impacts of Degradation on Water, Energy, and Carbon Cycling of the Amazon Tropical Forests Type Journal Article
  Year 2020 Publication Journal of Geophysical Research: Biogeosciences Abbreviated Journal J. Geophys. Res. Biogeosci.  
  Volume (down) 125 Issue 8 Pages e2020JG005677  
  Keywords Amazon; drought; ecosystem modeling; evapotranspiration; forest degradation; remote sensing; carbon cycle; deforestation; dry season; evapotranspiration; hydrological cycle; logging (timber); net primary production; remote sensing; sensible heat flux; tropical forest; understory; water stress; Amazon River  
  Abstract Selective logging, fragmentation, and understory fires directly degrade forest structure and composition. However, studies addressing the effects of forest degradation on carbon, water, and energy cycles are scarce. Here, we integrate field observations and high-resolution remote sensing from airborne lidar to provide realistic initial conditions to the Ecosystem Demography Model (ED-2.2) and investigate how disturbances from forest degradation affect gross primary production (GPP), evapotranspiration (ET), and sensible heat flux (H). We used forest structural information retrieved from airborne lidar samples (13,500 ha) and calibrated with 817 inventory plots (0.25 ha) across precipitation and degradation gradients in the eastern Amazon as initial conditions to ED-2.2 model. Our results show that the magnitude and seasonality of fluxes were modulated by changes in forest structure caused by degradation. During the dry season and under typical conditions, severely degraded forests (biomass loss ≥66%) experienced water stress with declines in ET (up to 34%) and GPP (up to 35%) and increases of H (up to 43%) and daily mean ground temperatures (up to 6.5°C) relative to intact forests. In contrast, the relative impact of forest degradation on energy, water, and carbon cycles markedly diminishes under extreme, multiyear droughts, as a consequence of severe stress experienced by intact forests. Our results highlight that the water and energy cycles in the Amazon are driven by not only climate and deforestation but also the past disturbance and changes of forest structure from degradation, suggesting a much broader influence of human land use activities on the tropical ecosystems. ©2020. The Authors.  
  Address AMAP, Univ Montpellier, IRD, CIRAD, CNRS, INRAE, Montpellier, France  
  Corporate Author Thesis  
  Publisher Blackwell Publishing Ltd Place of Publication Editor  
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  Series Volume Series Issue Edition  
  ISSN 21698953 (Issn) ISBN Medium  
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  Notes Approved no  
  Call Number EcoFoG @ webmaster @ Serial 957  
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Author Schmidt, M.; Dejean, A. doi  openurl
  Title A dolichoderine ant that constructs traps to ambush prey collectively: convergent evolution with a myrmicine genus Type Journal Article
  Year 2018 Publication Biological Journal of the Linnean Society Abbreviated Journal  
  Volume (down) 124 Issue 1 Pages 41-46  
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  Abstract Azteca brevis Forel, a dolichoderine ant species, builds along the branches of its host plant galleries that bear numerous holes slightly wider than a worker’s head. We noted that the workers hide, mandibles open, beneath different holes, waiting for arthropod prey to walk by or alight. They seize the extremities of these arthropods and pull backwards, immobilizing the prey, which is then spreadeagled and later carved up or pulled into a gallery before being carved up. The total duration of the capture ranges from a few minutes to several hours. This ambush group hunting permits the capture of insects of a wide range of sizes, with the largest being 48.71 times heavier than the workers, something that we compared with other cases of group hunting by ants and trap use by other arthropods. A convergence with myrmicine ants of the genus Allomerus is shown. Thus, this study also shows that the genus Azteca presents the largest panel of group hunting strategies by ants and that there is polyethism related to polymorphism, as hunting workers are larger than their nestmates. We concluded that these gallery-shaped traps correspond to the notion of ‘extended phenotype’.  
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  ISSN 0024-4066 ISBN Medium  
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  Notes 10.1093/biolinnean/bly028 Approved no  
  Call Number EcoFoG @ webmaster @ Serial 822  
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Author Soudani, K.; Hmimina, G.; Delpierre, N.; Pontailler, J.-Y.; Aubinet, M.; Bonal, D.; Caquet, B.; de Grandcourt, A.; Burban, B.; Flechard, C.; Guyon, D.; Granier, A.; Gross, P.; Heinesh, B.; Longdoz, B.; Loustau, D.; Moureaux, C.; Ourcival, J.-M.; Rambal, S.; Saint André, L.; Dufrêne, E. url  openurl
  Title Ground-based Network of NDVI measurements for tracking temporal dynamics of canopy structure and vegetation phenology in different biomes Type Journal Article
  Year 2012 Publication Remote Sensing of Environment Abbreviated Journal Remote Sens. Environ.  
  Volume (down) 123 Issue Pages 234-245  
  Keywords Crops; Evergreen and deciduous forests; Ground-based NDVI; Herbaceous savanna; NDVI time-series; Phenology; Tropical rain forest  
  Abstract Plant phenology characterises the seasonal cyclicity of biological events such as budburst, flowering, fructification, leaf senescence and leaf fall. These biological events are genetically pre-determined but also strongly modulated by climatic conditions, particularly temperature, daylength and water availability. Therefore, the timing of these events is considered as a good indicator of climate change impacts and as a key parameter for understanding and modelling vegetation-climate interactions. In situ observations, empirical or bioclimatic models and remotely sensed time-series data constitute the three possible ways for monitoring the timing of plant phenological events. Remote sensing has the advantage of being the only way of surface sampling at high temporal frequency and, in the case of satellite-based remote sensing, over large regions. Nevertheless, exogenous factors, particularly atmospheric conditions, lead to some uncertainties on the seasonal course of surface reflectance and cause bias in the identification of vegetation phenological events. Since 2005, a network of forest and herbaceous sites has been equipped with laboratory made NDVI sensors to monitor the temporal dynamics of canopy structure and phenology at an intra-daily time step. In this study, we present recent results obtained in several contrasting biomes in France, French Guiana, Belgium and Congo. These sites represent a gradient of vegetation ecosystems: the main evergreen and deciduous forest ecosystems in temperate climate region, an evergreen tropical rain forest in French Guiana, an herbaceous savanna ecosystem in Congo, and a succession of three annual crops in Belgium. In this paper, (1) we provide an accurate description of the seasonal dynamics of vegetation cover in these different ecosystems (2) we identify the most relevant remotely sensed markers from NDVI time-series for determining the dates of the main phenological events that characterize these ecosystems and (3) we discuss the relationships between temporal canopy dynamics and climate factors. In addition to its importance for phenological studies, this ground-based Network of NDVI measurement provides data needed for the calibration and direct validation of satellite observations and products. © 2012 Elsevier Inc.  
  Address INRA, Unité Biogéochimie des Ecosystèmes Forestiers, Champenoux, France  
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  ISSN 00344257 (Issn) ISBN Medium  
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  Notes Export Date: 16 August 2012; Source: Scopus; Coden: Rseea; doi: 10.1016/j.rse.2012.03.012; Language of Original Document: English; Correspondence Address: Soudani, K.; University of Paris-Sud, CNRS, AgroParisTech, Laboratoire Ecologie Systematique et Evolution, Faculty of Sciences of OrsayFrance; email: kamel.soudani@u-psud.fr Approved no  
  Call Number EcoFoG @ webmaster @ Serial 422  
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Author Soong, J.L.; Marañon-Jimenez, S.; Cotrufo, M.F.; Boeckx, P.; Bodé, S.; Guenet, B.; Peñuelas, J.; Richter, A.; Stahl, C.; Verbruggen, E.; Janssens, I.A. doi  openurl
  Title Soil microbial CNP and respiration responses to organic matter and nutrient additions: Evidence from a tropical soil incubation Type Journal Article
  Year 2018 Publication Soil Biology and Biochemistry Abbreviated Journal  
  Volume (down) 122 Issue Pages 141-149  
  Keywords 13c; Cnp; Microbial stoichiometry; Priming; Soil respiration; Tropics  
  Abstract Soil nutrient availability has a strong influence on the fate of soil carbon (C) during microbial decomposition, contributing to Earth's C balance. While nutrient availability itself can impact microbial physiology and C partitioning between biomass and respiration during soil organic matter decomposition, the availability of labile C inputs may mediate the response of microorganisms to nutrient additions. As soil organic matter is decomposed, microorganisms retain or release C, nitrogen (N) or phosphorus (P) to maintain a stoichiometric balance. Although the concept of a microbial stoichiometric homeostasis has previously been proposed, microbial biomass CNP ratios are not static, and this may have very relevant implications for microbial physiological activities. Here, we tested the hypothesis that N, P and potassium (K) nutrient additions impact C cycling in a tropical soil due to microbial stoichiometric constraints to growth and respiration, and that the availability of energy-rich labile organic matter in the soil (i.e. leaf litter) mediates the response to nutrient addition. We incubated tropical soil from French Guiana with a 13C labeled leaf litter addition and with mineral nutrient additions of +K, +N, +NK, +PK and +NPK for 30 days. We found that litter additions led to a ten-fold increase in microbial respiration and a doubling of microbial biomass C, along with greater microbial N and P content. We found some evidence that P additions increased soil CO2 fluxes. Additionally, we found microbial biomass CP and NP ratios varied more widely than CN in response to nutrient and organic matter additions, with important implications for the role of microorganisms in C cycling. The addition of litter did not prime soil organic matter decomposition, except in combination with +NK fertilization, indicating possible P-mining of soil organic matter in this P-poor tropical soil. Together, these results point toward an ultimate labile organic substrate limitation of soil microorganisms in this tropical soil, but also indicate a complex interaction between C, N, P and K availability. This highlights the difference between microbial C cycling responses to N, P, or K additions in the tropics and explains why coupled C, N and P cycle modeling efforts cannot rely on strict microbial stoichiometric homeostasis as an underlying assumption.  
  Address INRA, UMR Ecology of Guiana Forests (Ecofog), AgroParisTech, Cirad, CNRS, Université de Guyane, Université des Antilles, Kourou, France  
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  Notes Export Date: 16 May 2018 Approved no  
  Call Number EcoFoG @ webmaster @ Serial 804  
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Author Marcon, E.; Herault, B.; Baraloto, C.; Lang, G. url  doi
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  Title The decomposition of Shannon's entropy and a confidence interval for beta diversity Type Journal Article
  Year 2012 Publication Oikos Abbreviated Journal Oikos  
  Volume (down) 121 Issue 4 Pages 516-522  
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  Abstract Beta diversity is among the most employed theoretical concepts in ecology and biodiversity conservation. Up to date, a self-contained definition of it, with no reference to alpha and gamma diversity, has never been proposed. Using Kullback-Leibler divergence, we present the explicit formula of Shannon's β entropy, a bias correction for its estimator and a confidence interval. We also provide the mathematical framework to decompose Shannon diversity into several hierarchical nested levels. From botanical inventories of tropical forest plots in French Guiana, we estimate Shannon diversity at the plot, forest and regional level. We believe this is a complete and usefulness toolbox for ecologists interested in partitioning biodiversity. © 2011 The Authors. Oikos © 2012 Nordic Society Oikos.  
  Address AgroParisTech, UMR 518 Math. Info. Appli., 16 rue Claude Bernard, FR-75005 Paris, France  
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  ISSN 00301299 (Issn) ISBN Medium  
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  Notes Export Date: 28 March 2012; Source: Scopus; Coden: Oiksa; doi: 10.1111/j.1600-0706.2011.19267.x; Language of Original Document: English; Correspondence Address: Marcon, E.; AgroParisTech, UMR EcoFoG, BP 709, FR-97310 Kourou, France; email: eric.marcon@ecofog.gf Approved no  
  Call Number EcoFoG @ webmaster @ Serial 386  
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Author Lehnebach, R.; Beyer, R.; Letort, V.; Heuret, P. pdf  doi
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  Title The pipe model theory half a century on: a review Type Journal Article
  Year 2018 Publication Annals of Botany Abbreviated Journal  
  Volume (down) 121 Issue 5 Pages 773-795  
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  Abstract BackgroundMore than a half century ago, Shinozaki et al. (Shinozaki K, Yoda K, Hozumi K, Kira T. 1964a. A quantitative analysis of plant form – the pipe model theory. I. Basic analyses. Japanese Journal of Ecology B: 97–105) proposed an elegant conceptual framework, the pipe model theory (PMT), to interpret the observed linear relationship between the amount of stem tissue and corresponding supported leaves. The PMT brought a satisfactory answer to two vividly debated problems that were unresolved at the moment of its publication: (1) What determines tree form and which rules drive biomass allocation to the foliar versus stem compartments in plants? (2) How can foliar area or mass in an individual plant, in a stand or at even larger scales be estimated? Since its initial formulation, the PMT has been reinterpreted and used in applications, and has undoubtedly become an important milestone in the mathematical interpretation of plant form and functioning.ScopeThis article aims to review the PMT by going back to its initial formulation, stating its explicit and implicit properties and discussing them in the light of current biological knowledge and experimental evidence in order to identify the validity and range of applicability of the theory. We also discuss the use of the theory in tree biomechanics and hydraulics as well as in functional–structural plant modelling.ConclusionsScrutinizing the PMT in the light of modern biological knowledge revealed that most of its properties are not valid as a general rule. The hydraulic framework derived from the PMT has attracted much more attention than its mechanical counterpart and implies that only the conductive portion of a stem cross-section should be proportional to the supported foliage amount rather than the whole of it. The facts that this conductive portion is experimentally difficult to measure and varies with environmental conditions and tree ontogeny might cause the commonly reported non-linear relationships between foliage and stem metrics. Nevertheless, the PMT can still be considered as a portfolio of properties providing a unified framework to integrate and analyse functional–structural relationships.  
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  ISSN 0305-7364 ISBN Medium  
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  Notes 10.1093/aob/mcx194 Approved no  
  Call Number EcoFoG @ webmaster @ Serial 801  
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Author Lehnebach, R.; Beyer, R.; Letort, V.; Heuret, P. doi  openurl
  Title Corrigendum: The pipe model theory half a century on: A review (Annals of Botany DOI: 10.1093/aob/mcx194) Type Journal Article
  Year 2018 Publication Annals of Botany Abbreviated Journal Annals of Botany  
  Volume (down) 121 Issue 7 Pages 1427  
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  Abstract There was an error in the affiliations of Véronique Letort. The correct affiliation is Laboratory of Mathematics in Interaction with Computer Science (MICS), CentraleSupélec, France The online paper has been corrected.  
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  Notes Export Date: 16 July 2018 Approved no  
  Call Number EcoFoG @ webmaster @ Serial 810  
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Author Paine, C.E.T.; Baraloto, C.; Chave, J.; Herault, B. openurl 
  Title Functional traits of individual trees reveal ecological constraints on community assembly in tropical rain forests Type Journal Article
  Year 2011 Publication Oikos Abbreviated Journal Oikos  
  Volume (down) 120 Issue 5 Pages 720-727  
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  Abstract Niche differentiation and ecological filtering are primary ecological processes that shape community assembly, but their relative importance remains poorly understood. Analyses of the distributions of functional traits can provide insight into the community structure generated by these processes. We predicted the trait distributions expected under the ecological processes of niche differentiation and environmental filtering, then tested these predictions with a dataset of 4672 trees located in nine 1-ha plots of tropical rain forest in French Guiana. Five traits related to leaf function (foliar N concentration, chlorophyll content, toughness, tissue density and specific leaf area), and three traits related to stem function (trunk sapwood density, branch sapwood density, and trunk bark thickness), as well as laminar surface area, were measured on every individual tree. There was far more evidence for environmental filtering than for niche differentiation in these forests. Furthermore, we contrasted results from species-mean and individual-level trait values. Analyses that took within-species trait variation into account were far more sensitive indicators of niche differentiation and ecological filtering. Species-mean analyses, by contrast, may underestimate the effects of ecological processes on community assembly. Environmental filtering appeared somewhat more intense on leaf traits than on stem traits, whereas niche differentiation affected neither strongly. By accounting for within-species trait variation, we were able to more properly consider the ecological interactions among individual trees and between individual trees and their environment. In so doing, our results suggest that the ecological processes of niche differentiation and environmental filtering may be more pervasive than previously believed.  
  Address [Paine, C. E. Timothy] ENGREF, UMR Ecol Forets Guyane, Kourou 97387, French Guiana, Email: timothy.paine@ieu.uzh.ch  
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  Publisher Wiley-Blackwell Place of Publication Editor  
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  ISSN 0030-1299 ISBN Medium  
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  Notes ISI:000289740200008 Approved no  
  Call Number EcoFoG @ webmaster @ Serial 313  
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Author Salvin, P.; Roos, C.; Robert, F. url  openurl
  Title Tropical mangrove sediments as a natural inoculum for efficient electroactive biofilms Type Journal Article
  Year 2012 Publication Bioresource Technology Abbreviated Journal Bioresour. Technol.  
  Volume (down) 120 Issue Pages 45-51  
  Keywords Chronoamperometry; Cyclic voltammetry; Electroactive biofilms; Microbial fuel cells; Three-electrode systems  
  Abstract Chronoamperometry is known to be an efficient way to form electroactive biofilms (EAB) on conductive electrodes. For the first time, tropical mangrove sediments are analyzed as a potential inoculum to form MFC anodes with the use of acetate as substrate. The performance of the EAB-coated carbon cloth electrodes are evaluated according to the maximal current density, the coulombic efficiency and the cyclic voltammogramms. Working electrodes (WE) polarized at -0.2V/SCE gave better results compared to -0.4V/SCE and 0.0V/SCE. The maximal current density attained was 12A/m 2 with a CE of 24%. Contributions of the EAB in the generation of current were discussed and mechanisms of electronic transfer by the bacteria were discussed. Epifluorescence and SEM images showed the evolution of the biofilms on the electrode surface and the heterogeneity of the structure. © 2012 Elsevier Ltd.  
  Address Laboratoire des Matériaux et des Molécules en Milieu Amazonien, Université des Antilles et de la Guyane, UAG-UMR ECOFOG, F-97337 Cayenne, French Guiana  
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  ISSN 09608524 (Issn) ISBN Medium  
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  Notes Export Date: 16 August 2012; Source: Scopus; Coden: Birte; doi: 10.1016/j.biortech.2012.05.131; Language of Original Document: English; Correspondence Address: Robert, F.; Laboratoire des Matériaux et des Molécules en Milieu Amazonien, Université des Antilles et de la Guyane, UAG-UMR ECOFOG, F-97337 Cayenne, French Guiana; email: florent.robert@guyane.univ-ag.fr Approved no  
  Call Number EcoFoG @ webmaster @ Serial 421  
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Author Ezanno, P.; Aubry-Kientz, M.; Arnoux, S.; Cailly, P.; L'Ambert, G.; Toty, C.; Balenghien, T.; Tran, A. url  openurl
  Title A generic weather-driven model to predict mosquito population dynamics applied to species of Anopheles, Culex and Aedes genera of southern France Type Journal Article
  Year 2015 Publication Preventive Veterinary Medicine Abbreviated Journal Preventive Veterinary Medicine  
  Volume (down) 120 Issue 1 Pages 39-50  
  Keywords Mathematical modelling; Mosquito; Population dynamics; Seasonality; Sensitivity analysis; Surveillance  
  Abstract An accurate understanding and prediction of mosquito population dynamics are needed to identify areas where there is a high risk of mosquito-borne disease spread and persistence. Simulation tools are relevant for supporting decision-makers in the surveillance of vector populations, as models of vector population dynamics provide predictions of the greatest risk periods for vector abundance, which can be particularly helpful in areas with a highly variable environment. We present a generic weather-driven model of mosquito population dynamics, which was applied to one species of each of the genera Anopheles, Culex, and Aedes, located in the same area and thus affected by similar weather conditions. The predicted population dynamics of Anopheles hyrcanus, Culex pipiens, and Aedes caspius were not similar. An. hyrcanus was abundant in late summer. Cx. pipiens was less abundant but throughout the summer. The abundance of both species showed a single large peak with few variations between years. The population dynamics of Ae. caspius showed large intra- and inter-annual variations due to pulsed egg hatching. Predictions of the model were compared to longitudinal data on host-seeking adult females. Data were previously obtained using CDC-light traps baited with carbon dioxide dry ice in 2005 at two sites (. Marais du Viguerat and Tour Carbonnière) in a favourable temperate wetland of southern France (Camargue). The observed and predicted periods of maximal abundance for An. hyrcanus and Cx. pipiens tallied very well. Pearson's coefficients for these two species were over 75% for both species. The model also reproduced the major trends in the intra-annual fluctuations of Ae. caspius population dynamics, with peaks occurring in early summer and following the autumn rainfall events. Few individuals of this species were trapped so the comparison of predicted and observed dynamics was not relevant. A global sensitivity analysis of the species-specific models enabled us to identify the parameters most influencing the maximal abundance of mosquitoes. These key parameters were almost similar between species, but not with the same contributions. The emergence of adult mosquitoes was identified as a key process in the population dynamics of all of the three species considered here. Parameters associated with adult emergence therefore need to be precisely known to achieve accurate predictions. Our model is a flexible and efficient tool that predicts mosquito abundance based on local environmental factors. It is useful to and already used by a mosquito surveillance manager in France. © 2015 Elsevier B.V.  
  Address Université des Antilles et de la Guyane, UMR 'Ecologie des Forêts de Guyane'Kourou, France  
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  Notes Cited By :1; Export Date: 18 May 2015 Approved no  
  Call Number EcoFoG @ webmaster @ Serial 603  
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