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There is a growing body of evidence to suggest that certain polycyclic aromatic hydrocarbons (PAHs) pose a greater hazard to aquatic organisms than previously demonstrated, due to their potential to cause photo-induced toxicity when exposed to ultraviolet (UV) radiation. The consequences of photo-induced toxicity are reported here for embryo-larval stages of the pacific oyster Crassostrea gigas, following exposure to pyrene and benzo[a]pyrene. During laboratory investigations, significant increases in toxicity were observed in the presence of environmentally attainable levels of UV-radiation, compared with embryos exposed to PAH alone, at levels previously deemed to have little acute biological effect. The phototoxicity of pyrene and benzo[a]pyrene completely inhibited the development to the D-shell larval stage when embryos were simultaneously exposed to 5 microg l(-1) PAH and ultraviolet light (UVB = 6.3 +/- 0.1 microW/cm2 and UVA = 456.2 +/- 55 microW/cm2). A linear relationship was also demonstrated for benzo[a]pyrene phototoxicity with decreasing UV light intensity. 相似文献
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Simon Mardle Sean Pascoe Jean Boncoeur Bertrand Le Gallic Juan J. García-Hoyo Ins Herrero Ramon Jimenez-Toribio Concepcin Cortes Nuria Padilla Jesper Raakjaer Nielsen Christoph Mathiesen 《Marine Policy》2002,26(6)
The main objectives of fisheries management are generally similar throughout the world. These are often stated in policy documents such as the Common Fisheries Policy and the Magnuson–Stevens Fishery Conservation and Management Act. However, at the local level often the key objectives of management are more detailed, characterised by both the overriding management structure and the status and type of fishery concerned. In this paper, we consider case study fisheries from the UK, France, Spain and Denmark to compare some of the various types of fisheries and fisheries management systems that exist in the European Union. From this, we define the key objectives for each management system. 相似文献
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Economics, fisheries, and the marine environment 总被引:1,自引:2,他引:1
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ROBERT LAGERBÄCK 《Boreas: An International Journal of Quaternary Research》1988,17(4):469-486
The Veikimoraines in northernmost Sweden display a very conspicuous distribution pattern, sharply demarcated to the east and successively decreasing to the south, west and north. The sharp demarcation to the east is thought to reflect the front of a stagnant ice sheet. The downwasting of this glacier was retarded by the insulation of a thick superglacial debris cover and subarctic vegetation invaded at least parts of the slowly collapsing ice. Radiocarbon datings of organic matter deposited in connection with the formation of the Veiki moraine, lithostratigraphical evidence and the relation to other glacial features prove the Veiki moraine landscape to date from the deg laciation of the first Weichselian ice sheet, i.e. the Peräpohjola Interstadial. The good preservation of the features implies that in extensive areas of northern sweden the Early Weichselian glacial landscape escaped significant erosion despite being overrun by two later glaciers. Previous interpretations of the Late Weichselian/Holocene deglaciation are largely based on an Early Weichselian deglaciation pattern. 相似文献
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Richard T. Pascoe John P. Penny 《International journal of geographical information science》2013,27(3):275-291
Abstract An interface is a software package used, alone or in conjunction with other interfaces, to transfer data from one geographical information system to another, or between different representations within a single GIS. The aim in this paper is to extend the traditional view of an interface to include interfaces that use communication networks to move data between (and within) GIS. We suggest that, to exchange data across a network, the best solution may be to construct a set of communicating interfaces, each able to send data to, and receive data from, other communicating interfaces. We describe a working set of communicating interfaces that transfer data between a number of GIS data representations. 相似文献
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Fisher's behaviour with individual vessel quotas—Over-capacity and potential rent: Five case studies
Frank Asche Hkan Eggert Eyjolfur Gudmundsson Ayoe Hoff Sean Pascoe 《Marine Policy》2008,32(6):920-927
Internationally, individual vessel quotas (IVQ) have become an increasingly popular management tool. The main attraction of IVQs is the incentives they create for cost savings, autonomous capacity adjustment and, subsequently, rent generation. In this paper, the extent to which different IVQ systems have facilitated resource rent generation and capacity adjustment in five European countries—Denmark, Iceland, Norway, Sweden and the UK—is examined. The potential economic rents and the capacity reduction necessary to achieve these rents in each of the fisheries are also estimated. Reasons why IVQs have not achieved their potential economic benefits in these fisheries are also examined. 相似文献
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Sean Pascoe Rodrigo Bustamante Chris Wilcox Mark Gibbs 《Ocean & Coastal Management》2009,52(2):130-138
In many circumstances, quantitative assessment of fisheries management options is either impossible due to data deficiencies or impractical given the size of the fishery. Quantitative analysis of spatial management options in particular is complicated, as information on spatial fleet and stock dynamics is often unavailable and spatial models are difficult to construct. In this paper, a qualitative framework is presented that aids in the analysis of alternative spatial management options in coastal fisheries. The framework combines expert opinion and the Analytic Hierarchy Process (AHP) to determine which options perform best taking into account the multiple objectives inherent in fisheries management. 相似文献