Auteurs, date et publication :
Auteurs Grégoire Vincent , Jean-François Molino , Lucile Marescot , Karim Barkaoui , Daniel Sabatier , Vincent Freycon , Jean Baptiste Roelens
Publication : Annals of Forest Science
Date : 2011
Volume : 68
Issue : 2
Pages : 357–370
Catégorie(s)
#CIRAD #FORET ParacouAuteurs, date et publication :
Auteurs J. Paul McLean , Tian Zhang , Sandrine Bardet , Jacques Beauchêne , Anne Thibaut , Bruno Clair , Bernard Thibaut
Publication : Annals of Forest Science
Date : 2011
Volume : 68
Issue : 4
Pages : 681–688
Catégorie(s)
#CIRAD #FORET ParacouAuteurs, date et publication :
Auteurs Clément Stahl , Benoit Burban , Jean-Yves Goret , Damien Bonal
Publication : Annals of Forest Science
Date : 2011
Volume : 68
Issue : 4
Pages : 771–782
Catégorie(s)
#CIRAD #FORET ParacouRésumé
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.
Auteurs, date et publication :
Auteurs Pascale C. Dubois-Fernandez , Thuy Le Toan , Sandrine Daniel , Hélène Oriot , Jerôme Chave , Lilian Blanc , Ludovic Villard , Malcolm W.J. Davidson , Michel Petit
Publication : IEEE Transactions on Geoscience and Remote Sensing
Date : 2025
Volume : 50
Issue : 8
Pages : 3228–3241
Catégorie(s)
#CIRAD #CNRS #FORET Nouragues #FORET ParacouAuteurs, date et publication :
Auteurs Eric Marcon , Bruno Hérault , Christopher Baraloto , Gabriel Lang
Publication : Oikos
Date : 2012
Volume : 121
Issue : 4
Pages : 516–522
Catégorie(s)
#CIRAD #CNRS #FORET Nouragues #FORET ParacouAuteurs, date et publication :
Auteurs Lena Gustafsson , Susan C. Baker , Jürgen Bauhus , William J. Beese , Angus Brodie , Jari Kouki , David B. Lindenmayer , Asko Lõhmus , Guillermo Martínez Pastur , Christian Messier , Mark Neyland , Brian Palik , Anne Sverdrup-Thygeson , W. Jan A. Volney , Adrian Wayne , Jerry F. Franklin
Publication : BioScience
Date : 2012
Volume : 62
Issue : 7
Pages : 633–645
Catégorie(s)
#CIRAD #FORET ParacouRésumé
Here we show that Daceton armigerum, an arboreal myrmicine ant whose workers are equipped with hypertrophied trap-jaw mandibles, is characterized by a set of unexpected biological traits including colony size, aggressiveness, trophobiosis and hunting behavior. The size of one colony has been evaluated at ca. 952,000 individuals. Intra- and interspecific aggressiveness were tested and an equiprobable null model used to show how D. armigerum colonies react vis-à-vis other arboreal ant species with large colonies; it happens that D. armigerum can share trees with certain of these species. As they hunt by sight, workers occupy their hunting areas only during the daytime, but stay on chemical trails between nests at night so that the center of their home range is occupied 24 hours a day. Workers tend different Hemiptera taxa (i.e., Coccidae, Pseudococcidae, Membracidae and Aethalionidae). Through group-hunting, short-range recruitment and spread-eagling prey, workers can capture a wide range of prey (up to 94.12 times the mean weight of foraging workers).
Auteurs, date et publication :
Auteurs Alain Dejean , Jacques H. C. Delabie , Bruno Corbara , Fréderic Azémar , Sarah Groc , Jérôme Orivel , Maurice Leponce , William Hughes
Publication : Plos One
Date : 2012
Volume : 7
Issue : 5
Pages : e37683
Catégorie(s)
#CIRAD #CNRS #FORET Nouragues #FORET ParacouAuteurs, date et publication :
Auteurs C. Albinet , P. Borderies , T. Koleck , F. Rocca , S. Tebaldini , L. Villard , T. Le Toan , A. Hamadi , D. Ho Tong Minh
Publication : IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing
Date : 2012
Volume : 5
Issue : 3
Pages : 1060–1066
Catégorie(s)
#CIRAD #FORET ParacouAuteurs, date et publication :
Auteurs Nathalie Fromin , Benjamin Porte , Robert Lensi , Jérôme Hamelin , Anne-Marie Domenach , Bruno Buatois , Jean-Christophe Roggy
Publication : Journal of Soils and Sediments
Date : 2012
Volume : 12
Issue : 7
Pages : 1030–1039
Catégorie(s)
#CIRAD #FORET ParacouRésumé
In this paper we present results from the ground-based ESA campaign TropiScat, aimed at evaluating the temporal coherence at P-band in a tropical forest in all polarizations and at different heights within the vegetation layers. The TropiScat equipment has been operated since October 2011 at the Paracou field station, French Guiana, to continuously produce height-range images of the forest below with a temporal sampling of 15 minutes. The forest temporal behaviour can then be captured by analyzing the interferometric coherence between images gathered at different times, considering time scales on the order of hours, days, and months. Temporal coherence at the ground level was found to be higher than 0.8 at 27 days in all polarimetric channels, whereas temporal coherence at canopy height was found to be about 0.8 at 4 days and about 0.65 at 27 days, witnessing coherence sensitivity to height. © 2013 IEEE.
Auteurs, date et publication :
Auteurs D. Ho Tong Minh , S. Tebaldini , F. Rocca , T. Le Toan , P. Borderies , T. Koleck , C. Albinet , L. Villard , A. Hamadi
Publication : International Geoscience and Remote Sensing Symposium (IGARSS)
Date : 2025
Pages : 1206–1209