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Le présent article pose comme hypothèse principale qu’il existe une spécificité insulaire en matière de changement climatique, tant dans le domaine géopolitique que dans le domaine économique. A la différence des pays continentaux, le changement climatique est un facteur de structuration des États insulaires. Créée en 1990, 2 ans après que le GIEC commence ses travaux, l’Alliance des Petits États insulaires (AOSIS) s’est beaucoup investie dans la ratification du Protocole de Kyoto. Ces derniers se considèrent en effet comme les premières et principales victimes du changement climatique dont le coût pour leurs économies sera nettement plus élevé que celui supporté par les pays continentaux. Aux coûts directs, résultant de l’aléa naturel, notamment la montée du niveau de la mer et l’érosion du littoral qui lui est associée, se surimposeront des coûts induits par les mesures prises au niveau international pour lutter contre le changement climatique. Ces mesures conduisent à remettre la distance géographique au cœur de la logique de localisation des entreprises. La limitation des déplacements aériens et maritimes au long cours qui en résultera devrait entraîner une réduction de la demande mondiale pour les produits et services touristiques insulaires, suivie d’une concurrence exacerbée entre les îles pour attirer cette demande réduite. On assistera alors à la marginalisation des économies insulaires ne pouvant se positionner sur des marchés de niche aux échelles mondiales et régionales avec pour principaux corollaires l’exode rural et la migration internationale. Les recompositions économiques et territoriales qui s’annoncent sont des processus durables qui s’inscrivent dans le temps long. En revanche, le sommet de Copenhague a montré que la structuration politique des États insulaires sur la scène internationale est un processus fragile. L’AOSIS est sortie éclatée de ce sommet. L’avenir des îles est définitivement sous contrainte du changement climatique et il s’annonce bien sombre.

In this article is presented the preliminary evaluation of the performance of radiation transmission of glass block, used in support of photovoltaic cells, investigating different internal surface points of the block, which are subject to different shading during daylight hours. The aim is to establish how the edging setting, the only opaque element, can reduce the amount of light radiation during the day, introducing in this way a reduction of efficiency of the entire generation system. The generation system can be based on traditional photovoltaic cells or on the most suitable dye sensitized solar cells. An experimental measurement setup employing a microprocessor-based instrument has been created and a set of measures have been carried out. The measures prove that the shading effect at different irradiation angles do not affect significantly the lighting over the PV cell.

AbstractOcean warming is altering the biogeographical distribution of marine organisms. In the tropics, rising sea surface temperatures are restructuring coral reef communities with sensitive species being lost. At the biogeographical divide between temperate and tropical communities, warming is causing macroalgal forest loss and the spread of tropical corals, fishes and other species, termed “tropicalization”. A lack of field research into the combined effects of warming and ocean acidification means there is a gap in our ability to understand and plan for changes in coastal ecosystems. Here, we focus on the tropicalization trajectory of temperate marine ecosystems becoming coral‐dominated systems. We conducted field surveys and in situ transplants at natural analogues for present and future conditions under (i) ocean warming and (ii) both ocean warming and acidification at a transition zone between kelp and coral‐dominated ecosystems. We show that increased herbivory by warm‐water fishes exacerbates kelp forest loss and that ocean acidification negates any benefits of warming for range extending tropical corals growth and physiology at temperate latitudes. Our data show that, as the combined effects of ocean acidification and warming ratchet up, marine coastal ecosystems lose kelp forests but do not gain scleractinian corals. Ocean acidification plus warming leads to overall habitat loss and a shift to simple turf‐dominated ecosystems, rather than the complex coral‐dominated tropicalized systems often seen with warming alone. Simplification of marine habitats by increased CO2 levels cascades through the ecosystem and could have severe consequences for the provision of goods and services.

Effector genes, together with climatic and other environmental factors, play multifaceted roles in the development of plant diseases. Understanding the role of environmental factors, particularly climate conditions affecting the evolution of effector genes, is important for predicting the long-term value of the genes in controlling agricultural diseases. Here, we collected Phytophthora infestans populations from five locations along a mountainous hill in China and sequenced the effector gene Pi02860 from >300 isolates. To minimize the influence of other ecological factors, isolates were sampled from the same potato cultivar on the same day. We also expressed the gene to visualise its cellular location, assayed its pathogenicity and evaluated its response to experimental temperatures. We found that Pi02860 exhibited moderate genetic variation at the nucleotide level which was mainly generated by point mutation. The mutations did not change the cellular location of the effector gene but significantly modified the fitness of P. infestans. Genetic variation and pathogenicity of the effector gene were positively associated with the altitude of sample sites, possibly due to increased mutation rate induced by the vertical distribution of environmental factors such as UV radiation and temperature. We further found that Pi02860 expression was regulated by experimental temperature with reduced expression as experimental temperature increased. Together, these results indicate that UV radiation and temperature are important environmental factors regulating the evolution of effector genes and provide us with considerable insight as to their future sustainable action under climate and other environmental change.

To review the available evidence that examines the association between climatic and agricultural land use factors and the risks of enteric zoonoses in humans and consider information needs and possible pathways of intervention.The electronic databases PubMed, Web of Science and Embase and government websites were searched systematically for published literature that investigated the association of climatic and/or agricultural exposures with the incidence of the four most common enteric zoonotic diseases in New Zealand (campylobacteriosis, salmonellosis, cryptosporidiosis and giardiasis). Results The 16 studies in the review demonstrated significant associations between climate, agricultural land use and enteric disease occurrence. The evidence suggests that enteric disease risk from environmental reservoirs is pathogen specific. In some rural regions, environmental pathogen load is considerable, with multiple opportunities for zoonotic transmission.Enteric disease occurrence in NZ is associated with climate variability and agricultural land use. However, these relationships interact with demographic factors to influence disease patterns.Improved understanding of how environmental and social factors interact can inform effective public health interventions under scenarios of projected environmental change.

Abstract The Antarctic and Greenland ice contains an almost direct record of past atmospheric CH 4 . The record over the last 200 years reveals a spectacular 150% increase of the CH 4 atmospheric mixing ratio since pre-industrial times. At the scale of a glacial-interglacial cycle the record shows a remarkable correlation with climatic changes, with high (low) CH 4 levels during warm (cold) periods. A striking feature of the glacial-interglacial CH 4 record is the presence of large and abrupt (at the scale of a century or less) changes during the last glaciation and glacial-interglacial transition. The classical interpretation for the origin of CH 4 changes prior to the industrial era involves mainly the wetland source. In the context of gas hydrates the question is to know whether the past ice-core record contains fingerprints of catastrophic hydrate release (CHR). We currently conclude that the available record shows no evidence for CHR but additional ice-core analyses are necessary to reach a more definitive conclusion.

Acute oral administration of ethanol (3.2g/kg) to rats increased (DOPAC) levels in the caudate nucleus, but had no effect on DOPAC levels in the substantia nigra and frontal cortex and failed to modify dopamine content in any of the above areas. On the other hand, the administration of the same dose of ethanol to rats which had been chronically treated with ethanol (3.2g/kg daily for 60 days), produced a decrease of DA content and a parallel increase of DOPAC levels in all areas studied. In chronically treated rats, 24 hrs after last ethanol administration dopamine levels in the frontal cortex were 60% higher than in controls. The results suggest that ethanol administration causes dopamine release in different brain areas.