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Author Salas-Lopez, A.; Violle, C.; Mallia, L.; Orivel, J. url  doi
openurl 
  Title Land-use change effects on the taxonomic and morphological trait composition of ant communities in French Guiana Type Journal Article
  Year 2018 Publication (down) Insect Conservation and Diversity Abbreviated Journal Insect Conserv Divers  
  Volume 11 Issue 2 Pages 162-173  
  Keywords Community assembly; Formicidae; functional diversity; gradient analysis; habitat filtering; land-use intensification; n-dimensional hypervolume approach  
  Abstract Abstract Land-use changes frequently lead to major changes in the composition and diversity of organisms. A reduction in the range of strategies enabling organisms to survive in a given environment and changes in the average trait values of species may potentially be associated with variations in species? number and identity. We investigated the variation in ant taxonomic composition and morphological trait diversity along a land-use gradient in French Guiana. We measured 13 core ant morphological traits on all species sampled. We then selected the set of five traits that best captured changes along the land-use gradient. Potential effects of the variation in morphological trait diversity and average values were evaluated by examining morphological traits individually as well as in combination. We found that variation in taxonomic diversity was unrelated to the plot-level morphospace. Conversely, a significant shift in taxonomic composition was accompanied by changes in the average values of community traits along the studied gradient, examined both individually and in combination. We argue that morphological trait values may be related to the success of different species in surviving in a given environment and, therefore, are indicative of the taxonomic turnover in ants along the land-use gradient. Nevertheless, in contradiction with theoretical expectations, the morphospace is only slightly affected by habitat filtering and loosely impacted by taxonomic changes. Examining the sensitivity of the morphospace to abiotic and biotic factors and how it reflects varying ecological pressures for species is thus of the utmost importance.  
  Address  
  Corporate Author Thesis  
  Publisher John Wiley & Sons, Ltd (10.1111) Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1752-458x ISBN Medium  
  Area Expedition Conference  
  Notes doi: 10.1111/icad.12248 Approved no  
  Call Number EcoFoG @ webmaster @ Serial 892  
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Author Leponce, Maurice ; Dejean, Alain ; Mottl, Ondrej ; Klimes, Petr doi  openurl
  Title Rapid assessment of the three-dimensional distribution of dominant arboreal ants in tropical forests Type Journal Article
  Year 2021 Publication (down) Insect Conservation and Diversity Abbreviated Journal  
  Volume 14 Issue 4 Pages 426-438  
  Keywords  
  Abstract Ants are omnipresent in tropical forests, especially territorially dominant arboreal ants whose territories are spatially segregated forming ‘ant mosaics’. These ecologically important species are rarely used in conservation monitoring because of the difficulty in collecting them. We developed a standardised baitline protocol to study the distribution of dominant ants on canopy trees and also a procedure to objectively define species dominance, even in unknown ant assemblages.
Besides eliminating the need to climb trees, this protocol allows live arboreal ant specimens to be sampled at different heights. Behavioural aggressiveness assays between the collected workers provide data on the three-dimensional distribution of colonies and on interactions between species. We compared the results of the behavioural tests to those from null models.
In the New Guinean lowland forest studied, we show that the canopy was either shared by multiple territorial species or inhabited by a single species with a large territory. The baitline protocol collected up to half of the arboreal ant species found in a felling census. However, the proportion of species collected at baits decreased with the increasing spatial dominance of single territorial species.
Behavioural observations used in the protocol allowed a more efficient detection of ant mosaics than null models. Territorially dominant ants were active on both understorey and canopy trees.
The protocol is fast and easy to replicate. It is a potential tool for understanding and monitoring the spatiotemporal dynamics of arboreal ant assemblages and can detect populous colonies, including those of invasive species
 
  Address  
  Corporate Author Thesis  
  Publisher Royal Entomological Society Place of Publication Editor  
  Language Summary Language Original Title  
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  Notes Approved no  
  Call Number EcoFoG @ webmaster @ Serial 1047  
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Author Lebrini, M.; Mbomekallé, I.M.; Dolbecq, A.; Marrot, J.; Berthet, P.; Ntienoue, J.; Sécheresse, F.; Vigneron, J.; Etcheberry, A. url  openurl
  Title Manganese(III)-containing wells-dawson sandwich-type polyoxometalates: Comparison with their manganese(II) counterparts Type Journal Article
  Year 2011 Publication (down) Inorganic Chemistry Abbreviated Journal Inorg. Chem.  
  Volume 50 Issue 14 Pages 6437-6448  
  Keywords  
  Abstract We present the synthesis and structural characterization, assessed by various techniques (FTIR, TGA, UV-vis, elemental analysis, single-crystal X-ray diffraction for three compounds, magnetic susceptibility, and electrochemistry) of five manganese-containing Wells-Dawson sandwich-type (WDST) complexes. The dimanganese(II)-containing complex, [Na2(H2O) 2MnII2(As2W15O 56)2]18- (1), was obtained by reaction of MnCl2 with 1 equiv of [As2W15O 56]12- in acetate medium (pH 4.7). Oxidation of 1 by Na2S2O8 in aqueous solution led to the dimanganese(III) complex [Na2(H2O)2Mn III2(As2W15O56) 2]16- (2), while its trimanganese(II) homologue, [Na(H2O)2MnII(H2O)Mn II2(As2W15O56) 2]17- (3), was obtained by addition of ca. 1 equiv of MnCl2 to a solution of 1 in 1 M NaCl. The trimanganese(III) and tetramanganese(III) counterparts, [MnIII(H2O)Mn III2(As2W15O56) 2]15- (4) and [MnIII2(H 2O)2MnIII2(As2W 15O56)2]12- (6), are, respectively, obtained by oxidation of aqueous solutions of 3 and [MnII2(H2O)2MnII2(As 2W15O56)2]16- (5) by Na2S2O8. Single-crystal X-ray analyses were carried out on 2, 3, and 4. BVS calculations and XPS confirmed that the oxidation state of Mn centers is +II for complexes 1, 3, and 5 and +III for 2, 4, and 6. A complete comparative electrochemical study was carried out on the six compounds cited above, and it was possible to observe the distinct redox steps MnIV/III and MnIII/II. Magnetization measurements, as a function of temperature, confirm the presence of antiferromagnetic interactions between the Mn ions in these compounds in all cases with the exception of compound 2. © 2011 American Chemical Society.  
  Address Laboratoire de Physico-Chimie de L'Etat Solide, ICMMO, Université Paris-Sud, Bâtiment 410, 91405 Orsay Cedex, France  
  Corporate Author Thesis  
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  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 00201669 (Issn) ISBN Medium  
  Area Expedition Conference  
  Notes Export Date: 21 October 2011; Source: Scopus; Coden: Inoca; doi: 10.1021/ic102237x; Language of Original Document: English; Correspondence Address: Mbomekallé, I.M.; Institut Lavoisier de Versailles, UMR 8180, CNRS Université de Versailles Saint-Quentin, 45 Avenue des Etats-Unis, 78035 Versailles Cedex, France; email: israel.mbomekalle@chimie.uvsq.fr Approved no  
  Call Number EcoFoG @ webmaster @ Serial 346  
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Author de Thoisy, Benoit ; Duron, Olivier ; Epelboin, Loïc ; Musset, Lise ; Quénel, Philippe ; Roche, Benjamin ; Binetruy, Florian ; Briolant, Sébastien ; Carvalho, Luisiane ; Chavy, Agathe : Couppié, Pierre ; and all ........................... doi  openurl
  Title Ecology, evolution, and epidemiology of zoonotic and vector-borne infectious diseases in French Guiana: Transdisciplinarity does matter to tackle new emerging threats Type Journal Article
  Year 2021 Publication (down) Infection, Génétics and Evolution Abbreviated Journal  
  Volume 93 Issue Pages 104916  
  Keywords  
  Abstract French Guiana is a European ultraperipheric region located on the northern Atlantic coast of South America. It constitutes an important forested region for biological conservation in the Neotropics. Although very sparsely populated, with its inhabitants mainly concentrated on the Atlantic coastal strip and along the two main rivers, it is marked by the presence and development of old and new epidemic disease outbreaks, both research and health priorities. In this review paper, we synthetize 15 years of multidisciplinary and integrative research at the interface between wildlife, ecosystem modification, human activities and sociodemographic development, and human health. This study reveals a complex epidemiological landscape marked by important transitional changes, facilitated by increased interconnections between wildlife, land-use change and human occupation and activity, human and trade transportation, demography with substantial immigration, and identified vector and parasite pharmacological resistance. Among other French Guianese characteristics, we demonstrate herein the existence of more complex multi-host disease life cycles than previously described for several disease systems in Central and South America, which clearly indicates that today the greater promiscuity between wildlife and humans due to demographic and economic pressures may offer novel settings for microbes and their hosts to circulate and spread. French Guiana is a microcosm that crystallizes all the current global environmental, demographic and socioeconomic change conditions, which may favor the development of ancient and future infectious diseases.  
  Address  
  Corporate Author Thesis  
  Publisher Elsevier Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
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  Area Expedition Conference  
  Notes Approved no  
  Call Number EcoFoG @ webmaster @ Serial 1052  
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Author Dubois-Fernandez, P.C.; Le Toan, T.; Daniel, S.; Oriot, H.; Chave, J.; Blanc, L.; Villard, L.; Davidson, M.W.J.; Petit, M. url  openurl
  Title The tropiSAR airborne campaign in French Guiana: Objectives, description, and observed temporal behavior of the backscatter signal Type Journal Article
  Year 2012 Publication (down) IEEE Transactions on Geoscience and Remote Sensing Abbreviated Journal IEEE Trans Geosci Remote Sens  
  Volume 50 Issue 8 Pages 3228-3241  
  Keywords Forestry; interferometry; polarimetric synthetic aperture radar  
  Abstract The TropiSAR campaign has been conducted in August 2009 in French Guiana with the ONERA airborne radar system SETHI. The main objective of this campaign was to collect data to support the Phase A of the 7th Earth Explorer candidate mission, BIOMASS. Several specific questions needed to be addressed to consolidate the mission concept following the Phase 0 studies, and the data collection strategy was constructed accordingly. More specifically, a tropical forest data set was required in order to provide test data for the evaluation of the foreseen inversion algorithms and data products. The paper provides a description of the resulting data set which is now available through the European Space Agency website under the airborne campaign link. First results from the TropiSAR database analysis are presented with two in-depth analyses about both the temporal radiometric variation and temporal coherence at P-band. The temporal variations of the backscatter values are less than 0.5 dB throughout the campaign, and the coherence values are observed to stay high even after 22 days. These results are essential for the BIOMASS mission. The observed temporal stability of the backscatter is a good indicator of the expected robustness of the biomass estimation in tropical forests, from cross-polarized backscatter values as regarding environmental changes such as soil moisture. The high temporal coherence observed after a 22-day period is a prerequisite for SAR Polarimetric Interferometry and Tomographic applications in a single satellite configuration. The conclusion then summarizes the paper and identifies the next steps in the analysis. © 2012 IEEE.  
  Address Institut de Recherche Pour le Développement, 31062 Toulouse, France  
  Corporate Author Thesis  
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  Language Summary Language Original Title  
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  Series Volume Series Issue Edition  
  ISSN 01962892 (Issn) ISBN Medium  
  Area Expedition Conference  
  Notes Export Date: 9 August 2012; Source: Scopus; Art. No.: 6146421; Coden: Igrsd; doi: 10.1109/TGRS.2011.2180728; Language of Original Document: English; Correspondence Address: Dubois-Fernandez, P.C.; Office National d'Études et de Recherches Aérospatiales, Department of Electromagnetism and Radarh, 91761 Palaiseau, France; email: pdubois@onera.fr Approved no  
  Call Number EcoFoG @ webmaster @ Serial 419  
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Author Essebtey, Salma El Idrissi ; Villard, Ludovic ; Borderies, Pierre ; Koleck, Thierry ; Burban, Benoït ; Le Toan, Thuy doi  openurl
  Title Long-Term Trends of P-Band Temporal Decorrelation Over a Tropical Dense Forest-Experimental Results for the BIOMASS Mission Type Journal Article
  Year 2021 Publication (down) IEEE Transactions on Geoscience and Remote Sensing Abbreviated Journal  
  Volume 60 Issue Pages 1-15  
  Keywords  
  Abstract Fostered by the upcoming BIOMASS mission, this article explores long-term trends of P-band temporal decorrelation over a tropical forest due to a time series of 617 days acquired during the TropiScat-2 experiment. The interest in this unique time series is twofold. First, it provides consistent statistics to monitor the yearly evolution of temporal coherences according to specific time scales of the BIOMASS tomographic and interferometric phases. Second, it provides key insights to explore new processing approaches with the combination of data from different orbit directions (ascending/descending) and different mission cycles separated by about seven months according to the current acquisition plan. For the first time, this study shows that 18-day coherences (corresponding to the time interval between the first and last acquisitions of the BIOMASS tomographic processing) can vary significantly according to rainy and dry seasons (medians from 0.3 to 0.9). The extension to time intervals of up to 90 days within both seasons and over two consecutive years puts forward the key role of the typical sporadic rainfalls occurring during dry periods in tropical rainforests, with a stronger impact on temporal coherence evolution compared to the more reproducible rainy seasons. Furthermore, outstanding values significantly above zero have been obtained for the 7- and 14-month coherences (medians of 0.35 and 0.2, respectively), opening the way to new methods of change detection. Overall, this study highlights the role of P-band temporal decorrelation not only as a disturbance factor for coherent applications but also as a relevant indicator of forest changes.  
  Address  
  Corporate Author Thesis  
  Publisher Institute of Electrical and Electronics Engineers Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
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  Area Expedition Conference  
  Notes Approved no  
  Call Number EcoFoG @ webmaster @ Serial 1060  
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Author Campillo, F.; Rossi, V. openurl 
  Title Convolution Particle Filter for Parameter Estimation in General State-Space Models Type Journal Article
  Year 2009 Publication (down) 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.  
  Address  
  Corporate Author Thesis  
  Publisher IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor 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 Aubry-Kientz, Mélaine ; Laybros, Anthony ; Weinstein, Ben ; Ball, James G. C. ; Jackson, Toby ; Coomes, David ; Vincent, Grégoire doi  openurl
  Title Multisensor data fusion for improved segmentation of individual tree crowns in dense tropical forests Type Journal Article
  Year 2021 Publication (down) IEEE Journal of Selected topics in Applied Earth Observations and Remote Sensing Abbreviated Journal  
  Volume 14 Issue Pages 3927-3936  
  Keywords  
  Abstract Automatic tree crown segmentation from remote sensing data is especially challenging in dense, diverse, and multilayered tropical forest canopies, and tracking mortality by this approach is even more difficult. Here, we examine the potential for combining airborne laser scanning (ALS) with multispectral and hyperspectral data to improve the accuracy of tree crown segmentation at a study site in French Guiana. We combined an ALS point cloud clustering method with a spectral deep learning model to achieve 83% accuracy at recognizing manually segmented reference crowns (with congruence >0.5). This method outperformed a two-step process that involved clustering the ALS point cloud and then using the logistic regression of hyperspectral distances to correct oversegmentation. We used this approach to map tree mortality from repeat surveys and show that the number of crowns identified in the first that intersected with height loss clusters was a good estimator of the number of dead trees in these areas. Our results demonstrate that multisensor data fusion improves the automatic segmentation of individual tree crowns and presents a promising avenue to study forest demography with repeated remote sensing acquisitions.  
  Address  
  Corporate Author Thesis  
  Publisher IEEE Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
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  Notes Approved no  
  Call Number EcoFoG @ webmaster @ Serial 1008  
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Author Hamadi, A.; Borderies, P.; Albinet, C.; Koleck, T.; Villard, L.; Ho Tong Minh, D.; Le Toan, T.; Burban, B. url  openurl
  Title Temporal coherence of tropical forests at P-band: Dry and rainy seasons Type Journal Article
  Year 2015 Publication (down) IEEE Geoscience and Remote Sensing Letters Abbreviated Journal IEEE Geosci. Remote Sens. Lett.  
  Volume 12 Issue 3 Pages 557-561  
  Keywords Biomass mission; forest scattering; ground-based experiment; P-band; range impulse response; temporal coherence  
  Abstract In this letter, the temporal coherence of tropical forest scattering at P-band is addressed by means of a ground-based experiment. The study is based on the TropiScat campaign in French Guiana, designed to support the Biomass mission, which will be the ESA 7th Earth Explorer mission. For Biomass, temporal coherence is a crucial parameter for coherent processing of polarimetric synthetic aperture radar (SAR) interferometry and SAR tomography in repeat-pass acquisitions. During the experiment, data were continuously collected for six months during both the rainy and dry seasons. For the rain-free days in both seasons, the coherence exhibits a daily cycle showing a high decorrelation during daytime, which is likely due to motion in the canopy. Up to a 20-day baseline, the coherence is much higher in the dry season than in the rainy season (> 0.8). From 20 to 40 days, it presents the same order of magnitude in both seasons [0.6, 0.7]. For larger temporal baselines, it becomes lower in the dry season. The results can be used to assess the long-term coherence of repeat-pass observations over a tropical forest. However, an extension of this study to several years and over other forest spots would be necessary to draw more general conclusions.  
  Address EcoFogKourou, France  
  Corporate Author Thesis  
  Publisher Institute of Electrical and Electronics Engineers Inc. Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1545598x (Issn) ISBN Medium  
  Area Expedition Conference  
  Notes Export Date: 21 October 2014; Correspondence Address: Hamadi, A.; Centre d'Etudes Spatiales de la BiosphèreFrance; Funding Details: ESA, European Space Agency Approved no  
  Call Number EcoFoG @ webmaster @ Serial 563  
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Author Ruelle, J.; Clair, B.; Beauchene, J.; Prevost, M.F.; Fournier, M. openurl 
  Title Tension wood and opposite wood in 21 tropical rain forest species 2. Comparison of some anatomical and ultrastructural criteria Type Journal Article
  Year 2006 Publication (down) IAWA Journal Abbreviated Journal IAWA J.  
  Volume 27 Issue 4 Pages 341-376  
  Keywords tension wood; opposite wood; tropical rain forest; vessels; wood anatomy; wood fibre  
  Abstract The anatomy of tension wood and opposite wood was compared in 21 tropical rain forest trees from 21 species belonging to 18 families from French Guyana. Wood specimens were taken from the upper and lower sides of naturally tilted trees. Measurement of the growth stress level ensured that the two samples were taken from wood tissues in a different mechanical state: highly tensile-stressed wood on the upper side, called tension wood and normally tensile-stressed wood on the lower side, called opposite wood. Quantitative parameters relating to fibres and vessels were measured on transverse sections of both tension and opposite wood to check if certain criteria can easily discriminate the two kinds of wood. We observed a decrease in the frequency of vessels in the tension wood in all the trees studied. Other criteria concerning shape and surface area of the vessels, fibre diameter or cell wall thickness did not reveal any general trend. At the ultrastructural level, we observed that the microfibril angle in the tension wood sample was lower than in opposite wood in all the trees except one (Licania membranacea).  
  Address UAG, ENGREF,UMR Ecol Forets Guyane, INRA,ECOFOG, CIRAD,CNRS, F-97379 Kourou, Guyana, Email: ruelle_j@kourou.cirad.fr  
  Corporate Author Thesis  
  Publisher INT ASSOC WOOD ANATOMISTS Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0928-1541 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000242437400001 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 171  
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