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1.
The issue of the status of the Northwest Passage has ebbed and flowed in U.S.-Canada relations for decades, but the effect of global warming in the Arctic has moved this issue from the largely academic and legalistic realms to the forefront of bilateral (and international) relations. Intimately linked to Canadian nationalism, U.S. adherence to the doctrine of freedom of the seas, and to politics in both nations, the opposing positions held by the two states can no longer afford to be implacably held. Rather, it is time to put pride and politics aside and return to the “special relationship” between Canada and the United States in order to effect meaningful and mutually beneficial continental security.  相似文献   

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This article focuses on Spain to explain individual variation in the strength of identification with Europe. It relies mainly on statistical analysis of a nationally representative survey conducted in March 2000, but also on historical and newspaper sources. The statistical results support Inglehart's hypotheses about the contribution of high degrees of cognitive mobilization and education to the development of a European identity, but contradict his Postmaterialism thesis. Also, they support Turner's and Tajfel's hypotheses about the role of positive group images in fostering identification with groups. Finally, they show that in Spain regional and national identities are compatible with a European identity. This result is consistent with Calhoun's and Brewer's view of nested group identities who do not see a priori incompatibility between nested identities. Furthermore, it supports the authors' claim that nested identities are potentially compatible, as in Spain, when they are not portrayed and seen as impinging on each other.  相似文献   

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Large seaweeds are often structurally dominant in subtidal and intertidal rocky shore benthic communities of the N.W. Atlantic. The mechanisms by which these algal assemblages are maintained are surprisingly different in the two habitats. In the subtidal community, kelps are dominant space competitors in the absence of strong grazing interactions. In contrast, the large perennial seaweeds of intertidal zones (fucoids and Chondrus crispus) are competitively inferior to both sessile filter feeders and ephemeral, pioneer algal species. Intertidal seaweed beds are maintained by carnivory of whelks, which reduces filter feeder populations, and by herbivorous periwinkles which reduce ephemeral algal populations. Through most of the intertidal zone, disturbance, both biological and physical, dictates which species shall compete and equilibrium conditions obtain subsequently.The roles of subtidal consumers are quite different. Sea urchins are the major algal herbivores and these voracious animals maintain an equilibrium state in which large tracts of subtidal coralline pavement are kept free of kelp forests. Urchins do not seem to play a successional facilitative role for kelps in the way that periwinkles do for fucoids in the intertidal. Control of herbivore populations is thus a key to the maintenance of subtidal foliose algal beds. It is clear that parasitic amoebas can decimate sea urchin populations so that kelp forest dominance is assured. However, the importance of carnivory in limiting urchins in the subtidal community is unclear in the absence of appropriate manipulation experiments. It is possible that carnivorous decapods and fin fish control sea urchin populations and hence foliose algal abundance, but this must remain speculative. The seaweed-dominated state of the subtidal system is an alternative equilibrium condition to the urchin/coralline alga configuration. The structure of the kelp beds is relatively uniform in responding to frequent small-scale, infrequent large-scale, or no, disturbance.  相似文献   

5.
The Arctic Waters and the Northwest Passage: A Final Revisit   总被引:1,自引:0,他引:1  
Climate change has reduced the extent and thickness of sea ice in the Arctic, making international shipping in the Northwest Passage a virtual certainty in the foreseeable future. Such future shipping raises the question of whether the Passage is or might become an international strait, with the consequent right of transit passage. This article examines the two possible legal bases for Canada's claim that the waters of the Canadian Arctic Archipelago are internal waters: a historic title and straight baselines. It also addresses the issue of the possible internationalization of the Passage, if Canada does not take preventive measures. Some such measures are recommended in the last part of the article.  相似文献   

6.
Current legislation in the European Union (EU) requires a risk assessment for industrial chemicals. The underlying procedures and paradigms of such EU risk assessment for new and existing chemicals are explained. The risk assessment is performed according to a harmonised methodology, laid down in the Technical Guidance Documents (TGD). Important new, technical risk assessment aspects covered in a recent revision round of the TGD are highlighted. The most prominent change in the environmental TGD part is the addition of the marine risk assessment, including a Persistent Bioaccumulation and Toxicity (PBT) assessment. In the human health part a significant change is the new data requirement for reproductive toxicity. The performance of both the risk assessment and the risk reduction phase of EU existing chemicals have been evaluated. An important conclusion was that our a priori knowledge on possible risks of chemicals is poor. The European Commission has recently launched a proposal (REACH) for drastically changing the risk management process of industrial chemicals in the EU. Major changes are a shift in responsibility from authorities to industry (including downstream users) for the safe use of chemicals, an acceleration of data collection for ‘non-assessed’ chemicals, and an authorization step for substances of very high concern.  相似文献   

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在对欧盟生物经济概念演变进行梳理的基础上,从欧盟与成员国两个层面对欧盟生物经济的政策过程进行了系统考察,分析并归纳出欧盟生物经济政策的特点,包括:与产业绿色转型结合,多方位促进人类经济社会的可持续发展;与农业多功能性结合,促进地区农村和农业的发展;重视生物经济发展的政策与技术双平台系统建设.在相关讨论中,进一步阐明生物经济发展的动力机制、农业在生物经济中的基础作用、生物经济的平台价值及其时代意义.  相似文献   

10.
In the early 1990s, the Northwest Atlantic Ocean underwent a fisheries‐driven ecosystem shift. Today, the iconic cod (Gadus morhua) remains at low levels, while Atlantic halibut (Hippoglossus hippoglossus) has been increasing since the mid‐2000s, concomitant with increasing interest from the fishing industry. Currently, our knowledge about halibut ecology is limited, and the lack of recovery in other collapsed groundfish populations has highlighted the danger of overfishing local concentrations. Here, we apply a Bayesian hierarchical spatiotemporal approach to model the spatial structure of juvenile Atlantic halibut over 36 years and three fisheries management regimes using three model parameters to characterize the resulting spatiotemporal abundance structure: persistence (similarity of spatial structure over time), connectivity (coherence of temporal pattern over space), and spatial variance (variation across the seascape). Two areas of high juvenile abundance persisted through three decades whereas two in the northeast are now diminished, despite the increased abundance and landings throughout the management units. The persistent areas overlap with full and seasonal area closures, which may act as refuges from fishing. Connectivity was estimated to be 250 km, an order of magnitude less than the distance assumed by the definition of the Canadian management units (~2,000 km). The underlying question of whether there are distinct populations within the southern stock unit cannot be answered with this model, but the smaller ~250 km scale of coherent temporal patterns suggests more complex population structure than previously thought, which should be taken into consideration by fishery management.  相似文献   

11.
Synopsis A recent analysis of size and age at sexual maturity ofArgentina silus on the Scotian Shelf is invalid because field maturity stage data collected during the non-spawning, quiescent stage of the reproductive cycle were unreliable for distinguishing between immature and resting mature stages. Thus two-thirds of the data used must be discounted. Utilization of different length measurement criteria for different years, for which no correction is made, could introduce substantial error in length at maturity estimates based on the remaining data. Age data collections were restricted to one 12 month period and thus were inadequate to characterize age at maturity by 5 yr time periods as attempted in this analysis. No attempt is made in the analysis to determine whether available samples adequately represent the population with regard to maturity i.e. whether immature and mature fish of the same length had an equal probability of being sampled. It is demonstrated here that maturity ogives can differ greatly depending on assumptions made concerning the representativeness of samples. Many of the criticisms made are likely valid for a series of papers on maturity of Atlantic coast fishes by the same author.  相似文献   

12.
In December 1997, one specimen of the Atlantic bumper, Chloroscombrus chrysurus was recorded for the first time in the Mediterranean Sea, off Almuñécar (Granada, Spain: 36° 43′ 26″ N; 3° 41′ 39″ W). This species probably entered the Mediterranean Sea via the Strait of Gibraltar.  相似文献   

13.
美国与欧盟的转基因食品安全性政策演变比对   总被引:2,自引:0,他引:2  
随着转基因食品的研究与发展,人们对待转基因食品的态度表现为主要以美国和欧盟为主的两种代表性政策.美国采取遵循可靠科学原则,坚决反对预防原则,即对转基因食品采取积极支持,自愿标识的宽松政策;欧盟采取谨慎预防原则,必须标识和可追溯.从管理原则出发,结合相应采取的监管措施和相关条例,对两国从开始颁布转基因食品政策到当下态势的发展,并结合最新出台的政策进行跟踪分析,比对美国及欧盟对这些指令和条例的执行情况.  相似文献   

14.
The European Union has been engaged in an effort to develop a marine strategy to protect the marine environment and a more encompassing integrated maritime policy that would provide a comprehensive system for the management of the uses of the marine areas of Europe. An earlier article by the author described the beginnings of this policy development; this article examines the subsequent 2008 Directive of the European Parliament and the Council, which establishes a framework for community action in the field of marine environmental policy. The Marine Strategy Framework Directive provides a plan of action with designated responsibilities and obligations and a schedule that is to be adhered to by member states and the European Commission. It represents a significant step in the European endeavor to advance ocean use management and sets the stage for future development of European marine policy.  相似文献   

15.
Synopsis The assertion has been made by Halliday (1987) that trends in size and age at maturity of Atlantic groundfish published by Beacham (1983a, b, c, d, e, f) are artifacts induced by errors in determining the sex of an individual, distinguishing between immature and mature fish, sampling fish outside of the regular spawning season, and by nonrandom sampling of the population. In particular, Halliday asserts that for the Atlantic argentine,Argentina silus analysis, the conclusions of Beacham (1983a) that: (1) median length at sexual maturity declined over time; and (2) males matured at older ages than did females are invalid owing to biases in both sampling and analysis. In fact, if some of the biases indicated by Halliday were significant, then the decline in median length at sexual maturity is enhanced and the conclusions of Beacham (1983a) reinforced. Size and age at sexual maturity are dynamic characters in many vertebrate populations, and the fact that they should change for Atlantic groundfish should not be surprising given variable exploitation patterns in the fisheries since 1960.  相似文献   

16.
Immigration and asylum are key political issues in Britain and the European Union. Yet the policies of states and supranational bodies seem to have had little success in preventing unwanted flows and effectively managing immigration and integration. This article examines three types of reasons for policy failure: factors arising from the social dynamics of the migratory process; factors linked to globalization and the North-South divide; and factors arising within political systems. Key issues include the role of migrant agency, the way the North-South divide encourages flows, and hidden agendas in national policies. EU efforts attempts to address the root causes of migration in countries of origin are discussed. The article concludes that migration policies might be more successful if they were explicitly linked to long-term political agendas concerned with trade, development and conflict prevention. Reducing North-South inequality is the real key to effective migration management.  相似文献   

17.
Problems resulting from contemporary patterns of ocean use and threats to the viability of the marine environment have led to reconsideration of ocean use governance in a number of states, including the United States, Australia, and Canada. For its part, the European Union has been working on the development of a Marine Strategy to safeguard the environment and a more encompassing Maritime Policy into which the Marine Strategy would be folded. The desired Maritime Policy would reflect a holistic perspective of ocean space, embody an ecosystem-based approach to ocean use management, and provide a broad framework for ocean/coastal management. As has been seen elsewhere, developing such a governance system is difficult both in terms of conceptualization and, subsequently, in operationalization. The June 2006 European Commission Green Paper on Maritime Policy sets the stage for a year of consultations designed to develop an effective governance system for ocean management. Institutional and policy changes will be needed and it will be necessary to balance the objectives of economic growth and protection of environmental sustainability. This article examines current developments in efforts to devise a coherent and integrated European Union approach to ocean management.  相似文献   

18.
In March 1995, Canadian fisheries authorities boarded and arrested the Spanish fishing vessel, Estai, outside the Canadian 200‐mile zone on the Grand Banks, an event that served to focus world attention on a dispute that had its origins in the failure of the 1982 United Nations Convention on the Law of the Sea to implement an effective conservation and management regime for fish stocks on the high seas, particularly with respect to fish stocks that straddle coastal states’ exclusive economic zones. This article examines the origins of the dispute, including the allegations relating to overfishing of North Atlantic Fisheries Organization‐recommended quotas, the background to the vessel's arrest, and the subsequent confrontation that occurred, both at diplomatic levels and on the high seas, between Canada and the European Union. An analysis is made of the case in international law for Canada's extension of jurisdiction beyond 200 miles pursuant to the provisions of Section 5 of the Coastal Fisheries Protection Act. Finally, the article examines the implications of the recently concluded Agreement on the Conservation and Management of Straddling Fish Stocks and Highly Migratory Fish Stocks for disputes of the kind that arose in the present case.  相似文献   

19.
Atlantic salmon have been reared in the British Columbia, Canada aquaculture industry since the early 1980s. No breeding programmes spanned the entire production period and pedigree records were not kept for broodstocks prior to or since importation. Of the three recognized industry strains, two are of European ancestry ('Mowi' from Norway and 'McConnell' from Scotland) and one is of North American heritage ('Cascade' from Gaspe, Quebec). We evaluated the amount and distribution of genetic variation within industry broodstocks by surveying microsatellite variation at 11 loci in 20 broodstock groups sampled from major production facilities. Allelic richness averaged 10.9 (range 5.8-13.8), compared with a value of 20.3 obtained for a North American wild population. Pairwise genetic distances (D(S)) between samples within strains were generally less than those between strains, with samples attributed to the same strain clustering together in a neighbour-joining dendrogram. Nevertheless, average distances between samples within the European strains were high (0.41 for Mowi; 0.71 for McConnell) but lower (0.06) for the Cascade strain. The reduced intra-sample and increased intra-strain genetic variation observed for the BC domesticated samples compared with wild populations was similar to observations for European domesticated Atlantic salmon. Evidence of introgression of the Cascade strain into European broodstocks was provided by the presence of large Ssa202 alleles (confined to North America in wild populations) in some Mowi and McConnell samples. Introgression likely also contributed to the decreased intercontinental genetic distance for the domesticated samples of this study compared with that observed for wild populations.  相似文献   

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