Éditeur(s) : Trinidad Guardian Trinidad Guardian
North America -- Trinidad and Tobago -- Caribbean -- Trinidad -- Port of Spain
Caribbean

UF00078617

Éditeur(s) : HAL CCSD European Geosciences Union
Résumé : International audience
The seasonal climate drivers of the carbon cycle in tropical forests remain poorly known, although these forests account for more carbon assimilation and storage than any other terrestrial ecosystem. Based on a unique combination of seasonal pan-tropical data sets from 89 experimental sites (68 include aboveground wood productivity measurements and 35 litter productivity measurements), their associated canopy photosynthetic capacity (enhanced vegetation index, EVI) and climate, we ask how carbon assimilation and aboveground allocation are related to climate seasonality in tropical forests and how they interact in the seasonal carbon cycle. We found that canopy photosynthetic capacity seasonality responds positively to precipitation when rainfall is < 2000 mm yr(-1) (water-limited forests) and to radiation otherwise (light-limited forests). On the other hand, independent of climate limitations, wood productivity and litterfall are driven by seasonal variation in precipitation and evapotranspiration, respectively. Consequently, light-limited forests present an asynchronism between canopy photosynthetic capacity and wood productivity. First-order control by precipitation likely indicates a decrease in tropical forest productivity in a drier climate in water-limited forest, and in current light-limited forest with future rainfall < 2000 mm yr(-1).
ISSN: 1726-4170

hal-01557759
https://hal.univ-lorraine.fr/hal-01557759
https://hal.univ-lorraine.fr/hal-01557759/document
https://hal.univ-lorraine.fr/hal-01557759/file/bg-13-2537-2016.pdf
DOI : 10.5194/bg-13-2537-2016

Éditeur(s) : HAL CCSD Oxford University Press (OUP)
Résumé : International audience
We report structural evidence of ductile strain localization in mantle pyroxenite from the spinel to plagioclase websterite transition in the Ronda Peridotite (southern Spain). Mapping shows that, in this domain, small-scale shear zones occurring at the base of the lithospheric section are systematically located within thin pyroxenite layers, suggesting that the pyroxenite was locally weaker than the host peridotite. Strain localization is associated with a sudden decrease of grain size and increasing volume fractions of plagioclase and amphibole as a result of a spinel to plagioclase phase transformation reaction during decompression. This reaction also fostered hydrogen extraction ('dehydroxylation') from clinopyroxene producing effective fluid saturation that catalyzed the synkinematic net-transfer reaction. This reaction produced fine-grained olivine and plagioclase, allowing the onset of grain-size sensitive creep and further strain localization in these pyroxenite bands. The strain localization in the pyroxenites is thus explained by their more fertile composition, which allowed earlier onset of the phase transition reactions. Geothermobarometry undertaken on compositionally zoned constituent minerals suggests that this positive feedback between reactions and deformation is associated with cooling from at least 1000°C to 700°C and decompression from 1*0 to 0*5 GPa.
ISSN: 0022-3530

hal-00941293
https://hal.archives-ouvertes.fr/hal-00941293
DOI : 10.1093/petrology/egt039

Éditeur(s) : HAL CCSD
Résumé : The social change which takes place in the French West Indies after the Second World War ensues from a historical interactive process. It occurs between 1946 and 1961, within the frame of the new dynamic fostered in the aftermath of the war. Here we refer to the new political status of Department, the outbreak of social conflicts during the process of decolonization, the public policies and the planning of “the economic and social development” of the overseas departments. The dynamic also includes the population growth with the birth of a new generation- from the sociological point of view. The aforementioned interaction instils the new type of society emerging in the French West Indies since the 1960’s, without drastically changing their colonial social structure. This transformation named “Departmentalization” seems paradoxical because it will generate “modern” social frustrations, while maintaining existing frustrations that stemmed from the plantation society. This process led to the transition from a slave society to a consumer society. It allows us to understand the persistence of a latent social unrest in these departments, in spite of the overall significant improvement of the living conditions during the early twentieth century.
La transformation sociale des Antilles françaises qui se produit après la Seconde Guerre mondiale résulte d’un processus interactif historique. Celui-ci se produit entre 1946 et 1961 autour des nouvelles dynamiques de l’après-guerre. Il s’agit du statut départemental, de la décolonisation avec l’explosion des conflits sociaux, de la politique publique de « développement économique et social » avec la planification dans les départements d’outre-mer, et de l’accroissement démographique avec l’apparition d’une nouvelle génération « sociologique ». C’est précisément cette interaction qui est à l’origine du nouveau type de société qui émerge aux Antilles à partir des années 1960 sans pour autant que leur structure sociale coloniale ne soit bouleversée. Cette construction qui prend le nom commun de « Départementalisation » est paradoxale car elle va générer des frustrations sociales « modernes », tout en maintenant des frustrations anciennes issues de la société de plantation. En induisant ainsi le passage d’un monde d’ « habitation » à un monde de consommation, cette construction permet de comprendre un peu mieux, le maintien, au début du XXIe siècle, d’un malaise social latent dans ces départements en dépit d’une amélioration sensible et générale des conditions de vie.
https://hal.archives-ouvertes.fr/tel-01675708

Droits : info:eu-repo/semantics/OpenAccess
tel-01675708
https://hal.archives-ouvertes.fr/tel-01675708
https://hal.archives-ouvertes.fr/tel-01675708/document
https://hal.archives-ouvertes.fr/tel-01675708/file/D%C3%A9colonisation%20et%20changement%20social%20aux%20Antilles%20fran%C3%A7aises%20%281946-1961%29%20-%20Ma%C3%ABl%20LAVENAIRE%202017.pdf

Éditeur(s) : Université des Antilles Études caribéennes
Résumé : A major goal of natural resource managers is to foster and maximize environmentally responsible behavior among resource users. Interpretation is the process of conveying a message to someone to (a) enhance the awareness and appreciation that the person has with their surroundings, and to (b) encourage pro-environmental actions. It is one management tool that can be used to influence the actions or inactions of recreational visitors. Effective interpretation prompts the target audience to take action and provides opportunities for the audience to take action. An understanding of behavior and behavior change guides interpretive efforts so that they are effective in influencing behavior. This paper investigates the application of behavioral principles to test the most effective interpretive messages in influencing snorkeler behavior in Mombasa Marine Park. Key messages were incorporated into a training workshop for all the snorkel boat operators and associated crew enabling them to deliver an interpretation program to their clientele. Results indicate that the introduced interpretation program successfully influenced the behavior of snorkeling clients (i.e. led to more pro-environmental snorkel behavior), and increased visitor satisfaction (largely due to the transfer of information through the guide).
Un objectif majeur de gestionnaires des ressources naturelles est de favoriser et d’optimiser le comportement respectueux de l’environnement parmi les utilisateurs des ressources. L’interprétation est le processus de transmission d’un message à quelqu’un pour (a) accroître la sensibilisation et l’appréciation que la personne de son environnement, et pour (b) encourager les actions pro-environnementales. C’est un outil de gestion qui peut être utilisé pour influencer les actions ou inactions lors des visites de loisirs. Une interprétation efficace oriente les actions du public et lui ouvre des possibilités d’action. Une compréhension du comportement et du changement du comportement guide les efforts d’interprétation afin qu’ils soient plus efficaces dans l’influence du comportement. Cet article étudie l’application des principes comportementaux pour tester l’interprétation la plus efficiente des messages qui influencent le comportement des randonneurs palmés dans le parc marin de Mombasa. Des messages clés ont été incorporés dans un atelier de formation destiné aux exploitants de bateaux de plongée avec tuba et à leur équipage pour formuler un programme d’interprétation à leur clientèle. Les résultats indiquent que le programme d’interprétation mis en place a réussi à influencer le comportement des clients de plongée en apnée (à savoir conduit à un comportement de plongée plus pro-environnement) et à augmenter la satisfaction des visiteurs (en grande partie en raison du transfert de l’information par le guide.
Kenya
Mombasa

Droits : info:eu-repo/semantics/openAccess
urn:doi:10.4000/etudescaribeennes.8840
http://journals.openedition.org/etudescaribeennes/8840