Éditeur(s) : HAL CCSD Wiley
Résumé : 1. Considerable debate surrounds the extent to which tropical forests can be managed for resource extraction while conserving biodiversity and ecosystem properties, which depend on functional composition. Here we evaluate the compatibility of these aims by examining the effects of logging on taxonomic and functional diversity and composition in a tropical forest. 2. Twenty years after selective logging, we inventoried 4140 stems regenerating in logging gaps and adjacent undisturbed areas, and we integrated a database of 13 functional traits describing leaf and wood economics of tropical trees. 3. We found no differences in taxonomic and functional richness among habitats, but logging gaps had significantly higher taxonomic and functional evenness. 4. Logging also effected striking, long-term changes in both species and functional composition. In particular, the xylem density of recruits in logging gaps was 6% less than in unlogged forests, leaves were 11% less tough and had 613% greater mineral nutrient concentrations. 5. Synthesis and applications. Our results suggest that managers of tropical forests should limit overall surface area converted to logging gaps by creating fewer, larger gaps during selective logging, to reduce impacts on the taxonomic and functional composition of the regenerating stand.
ISSN: 0021-8901

hal-01032420
https://hal.archives-ouvertes.fr/hal-01032420
DOI : 10.1111/j.1365-2664.2012.02164.x

Éditeur(s) : HAL CCSD Editions Paralia CFL
Résumé : Barrier island hydro-morphodynamics driven by typhoon events are the major concern of the project KUNSHEN (2011-2014). It aims at providing for a deep understanding of the peculiar dynamics of sand barriers where extreme events such as typhoons have a significant impact. We present the campaigns and the protocols achieved and planned in the project, on the Wan-tzu-liao sand barrier, Cigu Lagoon, Tainan, Taiwan, from October 2011 to January 2012, during the winter storm season and during summer 2012 during the typhoon season. A set of current profilers are deployed along a cross shore transect at 7, 4 and 2 meters deep. On the Wan-tzu-liao sand barrier, 3 columns of 3 pressiometers are deployed to survey the submersion. In the same time, morphological surveys are performed on the sand barrier with DGPS to analyse any change in the shoreline position, the beach slope, and the dynamics of sand beach features. A very preliminary analysis on these on-going field surveys suggests that the word "extreme" refers more to the consequence of the forcing on the sand barrier than the intensity of the forcing itself. The strategy developed in this first step will be refined to survey the next typhoon season, from May 2012 to October 2012.
ISSN: 1760-8716

hal-00854411
https://hal.archives-ouvertes.fr/hal-00854411
DOI : 10.5150/jngcgc.2012.034-M

Éditeur(s) : Paris : chez André Cailleau
Résumé : Nouvelle édition

Droits : Domaine public
Provenance : Archives territoriales de Guyane
Permalien : http://www.manioc.org/patrimon/GAD11002
GAD11002

Éditeur(s) : HAL CCSD
Résumé :  
absent
33. European Geosciences Union General Assembly
Vienne, Austria

hal-01032070
https://hal.archives-ouvertes.fr/hal-01032070

Éditeur(s) : HAL CCSD Wiley
Résumé : International audience
Large-scale conical and saucer-shaped sand injectites have been identified in the Upper Miocene sediments of the Lower Congo Basin. These structures are evidenced on the 3D high-resolution seismic data at about 600 ms TWT (two-way traveltime) beneath the seabed. The conical and saucer-shaped anomalies range from 20 to 80 m in height, 50 to 300 m in diameter, and 10 to 20 ms TWT in thickness. They are located within a sedimentary interval of about 100 m in thickness and are aligned over 20 km in dip direction (NE-SW), above the NW margin of an underlying Upper Miocene submarine fan. We have interpreted the conical and saucer-shaped anomalies as upward-emplaced sand injectites sourced from the Upper Miocene fan because of their discordant character, the postsedimentary uplifting of the sediments overlying the cones and saucer-shaped bodies, the alignment with the lateral fringe of the Upper Miocene submarine fan, and the geological context. Sand injection dates from the Miocene-Pliocene transition (approximately 5.3 Ma). The prerequisite overpressure to the sand injection process may be due to the buoyancy effect of hydrocarbons accumulated in the margins of the fan. Additionally, overpressure could have been enhanced by the lateral transfer of fluids operating in the inclined margins of the lobe. The short duration of sand injection and the presence of many sandstone intrusions suggested that the process of injection was triggered by an event, likely due to a nearby fault displacement related to diapiric movements. This is the first time that sand injectites of seismic scale have been described from the Lower Congo Basin. The localized nature of these injectites has led to a change in the migration path of fluids through the sedimentary cover. Consequently, the sand intrusions are both evidence and vectors of fluid migration within the basin fill.
ISSN: 1468-8115

hal-00963594
https://hal.archives-ouvertes.fr/hal-00963594
DOI : 10.1111/gfl.12057

Éditeur(s) : HAL CCSD Peter Lang
Résumé : International audience
https://hal.archives-ouvertes.fr/hal-01151982

hal-01151982
https://hal.archives-ouvertes.fr/hal-01151982

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
Magnetic Resonance Imaging (MRI), a reference examination for cardiac morphology and function in humans, allows to image the cardiac right ventricle (RV) with high spatial resolution. The segmentation of the RV is a difficult task due to the variable shape of the RV and its ill-defined borders in these images. The aim of this paper is to evaluate several RV segmentation algorithms on common data. More precisely, we report here the results of the Right Ventricle Segmentation Challenge (RVSC), concretized during the MICCAI'12 Conference with an on-site competition. Seven automated and semi-automated methods have been considered, along them three atlas-based methods, two prior based methods, and two prior-free, image-driven methods that make use of cardiac motion. The obtained contours were compared against a manual tracing by an expert cardiac radiologist, taken as a reference, using Dice metric and Hausdorff distance. We herein describe the cardiac data composed of 48 patients, the evaluation protocol and the results. Best results show that an average 80% Dice accuracy and a 1cm Hausdorff distance can be expected from semi-automated algorithms for this challenging task on the datasets, and that an automated algorithm can reach similar performance, at the expense of a high computational burden. Data are now publicly available and the website remains open for new submissions (http://www.litislab.eu/rvsc/).
ISSN: 1361-8415

hal-01141170
https://hal.archives-ouvertes.fr/hal-01141170
PUBMED : 25461337

Éditeur(s) : HAL CCSD Wiley
Résumé : International audience
The influence of conservation policies on environmental governance by indigenous peoples is not well understood. Our goal is to understand the role of conservation policies in the on-going social, spatial and temporal reorganisation of common natural resources management by the Wayãpi and Teko in French Guiana. Using socio-economic and land use variables, we explain their territorial reorganisation. We show how the delimitation of protected areas encourages identity claims and resources re-appropriation, which play a determining role in territorial reorganisation.Finally, we focus on the emergence of a new form of environmental governance based on “multi-sited” land use system.
ISSN: 0261-3050

Droits : info:eu-repo/semantics/OpenAccess
hal-01135244
https://hal.archives-ouvertes.fr/hal-01135244
https://hal.archives-ouvertes.fr/hal-01135244/document
https://hal.archives-ouvertes.fr/hal-01135244/file/Tritsch_al_Toward_revival_indigenous_mobility_Bull.Lat.Am.Research_2015.pdf
DOI : 10.1111/blar.12204

Éditeur(s) : HAL CCSD
Résumé : absent
7. Journées d'Ecologie Fonctionnelle
Super Besse, France

hal-01032031
https://hal.archives-ouvertes.fr/hal-01032031

Éditeur(s) : HAL CCSD Elsevier
Résumé : absent
ISSN: 0034-4257

hal-01019844
https://hal.archives-ouvertes.fr/hal-01019844
DOI : 10.1016/j.rse.2012.03.012

Éditeur(s) : HAL CCSD
Résumé :  
absent
Salon International de l'Agriculture

hal-01032109
https://hal.archives-ouvertes.fr/hal-01032109

Éditeur(s) : HAL CCSD Coastal Education and Research Foundation, Inc.
Résumé : International audience
Morphodynamics of sandy, macrotidal, embayed beaches is complex because of the numerous physical processes interacting at the same location over a wide range of temporal scales. As most of these processes are controlled by beach morphology, dynamic feedbacks are generally observed between hydro- and morphodynamics. Investigating short-term processes is essential in order to improve long term morphological prediction. A key question is to understand how beach slope reacts to forcing conditions, in particular the response time of the beach profile, how long the transient state lasts. This study deals with the spatial and temporal responses of beach morphology to varying incident conditions. Here we report main observations, preliminary results and on-going investigations on the DYNATREZ1 field campaign, which was conducted in the framework of the National Observation Service Dynalit. Beach profiles are shown to adapt rapidly to forcing conditions, within two days, with more intense variations observed in the high tide swash zone. The presence of infragravity waves and their dissipation on the beach is highlighted. It is likely that the very large variability in beach slope observed over a single neapspring cycle is responsible for the accordingly large variability in wave skewness, asymmetry and breaking processes, and thus in sediment fluxes and morphological changes.
ICS 2016 Sydney
Sydney, Australia

hal-01254465
https://hal.archives-ouvertes.fr/hal-01254465
DOI : 10.2112/SI75-075.1

Éditeur(s) : HAL CCSD Springer Verlag (Germany)
Résumé :  
We explored the relationship between soil processes, estimated through soil respiration (Rsoil), and the spatial variation in forest structure, assessed through the distribution of tree size, in order to understand the determinism of spatial variations in Rsoil in a tropical forest. The influence of tree size was examined using an index (Ic) calculated for each tree as a function of (1) the trunk cross section area and (2) the distance from the measurement point. We investigated the relationships between Ic and litterfall, root mass and Rsoil, respectively. Strong significant relationships were found between Ic and both litterfall and root mass. Rsoil showed a large range of variations over the 1-ha experimental plot, from 1.5 to 12.6 gC m−2 d−1. The best relationship between Ic and Rsoil only explained 17% of the spatial variation in Rsoil. These results support the assumption that local spatial patterns in litter production and root mass depend on tree distribution in tropical forests. Our study also emphasizes the modest contribution of tree size distribution-which is mainly influenced by the presence of the biggest trees (among the large range size of the inventoried trees greater than 10 cm diameter at 1.30 m above ground level or at 0.5 m above the buttresses)-in explaining spatial variations in Rsoil.
Plant and Soil

hal-01032200
https://hal.archives-ouvertes.fr/hal-01032200
DOI : 10.1007/s11104-011-0848-1

Éditeur(s) : HAL CCSD
Résumé :  
absent
Séminaire du "Dipartimento di Scienze Ambientali"
Naples, Italy

hal-01032045
https://hal.archives-ouvertes.fr/hal-01032045

Éditeur(s) : HAL CCSD Elsevier
Résumé : absent
Ecology and Management of a Neotropical Rainforest. Lessons drawn from Paracou, a long-term experimental research site in French Guiana

ISBN : 2-84299-455-8
hal-01189178
https://hal.archives-ouvertes.fr/hal-01189178
PRODINRA : 12114

Éditeur(s) : HAL CCSD
Résumé : International audience
o abstract
American Geophysical Union, Fall Meeting 2013
Unknown, United States

hal-01426587
https://hal.archives-ouvertes.fr/hal-01426587

Éditeur(s) : [S.l.] : [s.n.]
Siècle(s) traité(s) : 20
Provenance : Archives départementales de Guadeloupe
Permalien : http://www.manioc.org/patrimon/ADG18171
ADG18171

Éditeur(s) : HAL CCSD Royal Meteorological Society
Résumé : Assessing the impact/adaptation of human activities on/to climate change is a key issue, especially in the tropics that concentrate major anthropogenic dynamics such as deforestation and nearly two-thirds of the planetary rainfall. However, this task is often made tough because human activities such as agricultural dynamics are usually analysed at local or regional scale whereas climate related studies are led at large to global scales due to a lack of reliable data, especially in the tropics. In this article we argue that the increased spatial resolution of remote sensing-based rainfall estimates enables assessing the spatiotemporal variability of rainfall regimes at regional and local scales, thus allowing fine analysis of the interactions with human activities. We processed Tropical Rainfall Measuring Mission (TRMM) 3B42 daily rainfall estimates over the state of Mato Grosso (southern Brazilian Amazon) for the 1998-2012 study period in order to compute rainfall metrics such as annual rainfall and duration, onset and end dates of the rainy season based on the Anomalous Accumulation methodology (at a 0.25◦ spatial resolution). We then crossed these metrics with agricultural maps (produced at a 250m spatial resolution) and proved that the adoption of intensive agricultural practices such as double cropping systems is partly the result of a strategy to adapt practices to local climatic conditions. Finally, we discuss how such results raise important issues regarding the sustainability of the agricultural development model in the Southern Amazon.
International Journal of Climatology

halshs-00910825
https://halshs.archives-ouvertes.fr/halshs-00910825
DOI : 10.1002/joc.3863

Éditeur(s) : HAL CCSD Editions Paralia CFL
Résumé : Le lido de Villeneuve-lès-Maguelone (Languedoc-Roussillon) est un archétype de littoral microtidal, dominé par la houle, en érosion, et largement affecté par la submersion marine lors des tempêtes. Les observations réalisées dans le cadre du Système d'Observation Littoral - Trait de Côte (SO LTC) concernent l'hydrodynamique et le transport sédimentaire dans l'avant-côte et la lagune. La tache d'observation MAGOBS (Observatoire Aresquiers-Maguelone-Palavas) de cet observatoire regroupe un dispositif instrumental automatisé composé de 30 points d'acquisition en temps réel entre 6 mètres de profondeur et le haut de plage (à terre) ainsi que dans la lagune. Le dispositif est opérationnel depuis mai 2011. Son déploiement a permis de déverrouiller les difficultés techniques liées à la mesure temps réel en zone littorale : choix du type des appareils de mesure, de la technologie embarquée, des cadences d'acquisition, résolution des questions du transfert de la donnée. Le dispositif produit 2 Tera-octets de données par an. Les données sont stockées sur un ensemble de serveurs dédiés. Les données sont mises en ligne sur le site du SO-LTC (www.soltc.org), immédiatement après premiers traitements et qualification. Elles commencent à être utilisées pour des calculs de niveau d'eau à la côte, et dansdes outils de prédiction des vagues et des niveaux à la côte associant mesure et modélisation.
ISSN: 1760-8716

hal-00854410
https://hal.archives-ouvertes.fr/hal-00854410
DOI : 10.5150/jngcgc.2012.064-G

Éditeur(s) : HAL CCSD
Résumé : absent
Séminaire forêts hétérogènes du GIP ECOFOR
NA, France

hal-01269340
https://hal.archives-ouvertes.fr/hal-01269340
PRODINRA : 331590