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181.
Farmers’ Perceived Risks of Climate Change and Influencing Factors: A Study in the Mekong Delta,Vietnam 总被引:2,自引:0,他引:2
Many countries are confronting climate change that threatens agricultural production and farmers’ lives. Farmers’ perceived risks of climate change and factors influencing those perceived risks are critical to their adaptive behavior and well-planned adaptation strategies. However, there is limited understanding of these issues. In this paper, we attempt to quantitatively measure farmers’ perceived risks of climate change and explore the influences of risk experience, information, belief in climate change, and trust in public adaptation to those perceived risks. Data are from structured interviews with 598 farmers in the Mekong Delta. The study shows that perceived risks to production, physical health, and income dimensions receive greater priority while farmers pay less attention to risks to happiness and social relationships. Experiences of the events that can be attributed to climate change increase farmers’ perceived risks. Information variables can increase or decrease perceived risks, depending on the sources of information. Farmers who believe that climate change is actually happening and influencing their family’s lives, perceive higher risks in most dimensions. Farmers who think that climate change is not their concern but the government’s, perceive lower risks to physical health, finance, and production. As to trust in public adaptation, farmers who believe that public adaptive measures are well co-ordinated, perceive lower risks to production and psychology. Interestingly, those who believe that the disaster warning system is working well, perceive higher risks to finance, production, and social relationships. Further attention is suggested for the quality, timing, and channels of information about climate change and adaptation. 相似文献
182.
Edouard Lavergne Isabelle Calvès Anne Leila Meistertzheim Grégory Charrier Uwe Zajonz Jean Laroche 《Marine Biology》2014,161(5):1113-1126
Temporarily open/closed estuaries (TOCEs) are major ecosystems of the Indian Ocean coastal zones. Their functioning is tightly linked to climatic events such as monsoons and storms, and their mouth can close up for prolonged and variable periods of time, thus limiting their connectivity with the marine environment. Two types of genetic markers (i.e., mitochondrial cytochrome c oxidase I (COI) gene and microsatellites) were used to assess the genetic structure of 288 individuals of Terapon jarbua, a widely distributed fish species in the wider Gulf of Aden. Firstly, the hypothesis of panmixia was tested. Then, alternative hypotheses were investigated to explain the population genetic structure of T. jarbua: could it be shaped by (1) regional biogeographic barriers (i.e., Socotra Island vs. mainland Yemen) and/or (2) the particular functioning of TOCEs in relation to the species life cycle and particular physical ocean parameters? On one hand, the polymorphism of the COI inferred (1) a high haplotype diversity and a reduced nucleotide diversity over the whole data set and (2) a “star-like” shape of the haplotype network, thus suggesting a population expansion after local extinctions during the Pleistocene glaciations. On a second hand, the genotyping of eight microsatellites showed a significant genetic differentiation between T. jarbua populations in the wider Gulf of Aden (F ST = 0.035, p < 0.01), and thus, the panmixia hypothesis was rejected. Analyses of molecular variance results did not show any significant structure between Socotra Island and mainland Yemen and thus did not support the role of biogeographic barriers in structuring T. jarbua populations. Significant multi-locus deficits in heterozygotes at particular locations displaying high levels of F IS were recorded. It was suggested that a possible Wahlund effect took place in those TOCEs which could gather several cohorts of larvae stemming from different marine subpopulations over the sampled area. The present study emphasized the uniqueness of each TOCE as a potential reservoir of biodiversity and the urgent need for a better conservation program of those estuaries in the region, in order to avoid habitat fragmentation and permanent closure of those nursery areas by human activities. 相似文献
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J. Besseau-Ayasse C. Violle-Poirsier A. Bazin N. Gruchy A. Moncla F. Girard M. Till F. Mugneret A. Coussement F. Pelluard M. Jimenez P. Vago M. F. Portnoï C. Dupont C. Beneteau F. Amblard M. Valduga J. L. Bresson F. Carré-Pigeon N. Le Meur S. Tapia C. Yardin A. Receveur J. Lespinasse E. Pipiras M. P. Beaujard P. Teboul S. Brisset M. Catty E. Nowak N. Douet Guilbert H. Lallaoui S. Bouquillon V. Gatinois G. Joly-Helas F. Prieur F. Cartault D. Martin P. Kleinfinger D. Molina Gomes M. Doco-Fenzy F. Vialard 《黑龙江环境通报》2014,34(5):424-430
185.
A. Gauthier P. Le Coustumer M. Motelica O. F. X. Donard 《Waste management (New York, N.Y.)》2000,20(8)
The development of predictive models for the long term evolution of nuclear waste glass requires the complete knowledge of the glass dissolution at the laboratory scale. A new approach was developed to determine the initial reaction during the first steps of experience, a new concept was developed, based on the combination of dynamic leaching test and the characterization of the altered materials. With this experimental set-up it is possible to follow in real time the glass alteration process at a fine temporal scale. The results put in evidence a singular behaviour of the lanthanide, shown by a concentration peak of La, Nd and Ce after 2 h and a quick decrease of their concentration measured on line in the solution during the leaching test. This fact is directly linked to the development of an interphase (altered layer which differs from the initial solid by its texture, structure and chemical composition) at the interface of the glass surface and the leaching solution. This work is an attempt to integrate the formation of the alteration products (here the interphase) during leaching into the dissolution mechanisms of a nuclear waste glass. A model is proposed and discussed. 相似文献
186.
Food and Environmental Virology - The aim of the study was to assess human norovirus and feline calicivirus (FCV) surface free energy, hydrophobicity, and ability to interact with fresh foods and... 相似文献
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