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871.
During the last decade, devolution of responsibilities of fisheries management has increasingly become an issue in the political debate. The CEC and national governments have expressed an interest in sharing responsibilities for fisheries management with stakeholders. This article investigates the dynamics and constraints of the devolution process in general and in relation to Danish demersal fisheries by answering the following questions: What are the important factors to consider with respect to sharing responsibilities in fisheries management; how can this delegation and/or devolution of responsibilities be institutionalised? And what kind of decisions should be delegated to stakeholders and to whom?  相似文献   
872.
Carmen-Pia  Günther 《Marine Ecology》1996,17(1-3):117-130
Abstract. The development of temporary Mytilus edulis beds and their associated macro fauna was studied on an intertidal sand flat in the German Wadden sea during 1986 by comparing mussel beds with bare sandy areas of the same tidal elevation. Macro fauna samples We taken with a 100 cm2 corer (penetration depth 27 cm, mesh size 0.5 mm, 5 parallel samples).
Numbers of taxa and diversity were higher in the mussel beds compared to the sandy areas. The abundance of macro fauna organisms decreased with the age of the mussel bed, whereas the relative abundance of species was not strongly affected. Hydrobia ulvae , oligochaetes, and Heteromastus filiformis dominated the macro fauna inside as well as outside the mussel beds. Among the lower ranks of dominance changes in species composition were observed due to increasing densities of opportunistic polychaetes.
About six weeks after the establishment of the mussel beds a higher abundance of Capitella spp., Polydora ligni, Tharyx marioni , and nemerteans occurred within the mussel beds while other species such as Hydrobia ulvae and Pygospio elegans showed a significantly lower abundance compared to the adjacent flat. Macoma balthica as well as Mya arenaria were not affected by the alteration of a bare sand flat to a mussel bed. O-group Carcinus maenas reached their highest abundance in the mussel beds (over 1000 indiv. m-2). In contrast juvenile Crangon crangon preferred the bare sand flat. After destruction of the mussel beds by an early autumn storm, species abundance and composition was similar to the situation before the mussel beds had become established.  相似文献   
873.
金-厦海域环境综合管理机制探讨   总被引:1,自引:0,他引:1  
本文根据对金-厦海域自然条件、管理现状及两岸关系形势的分析,认为金-厦海域环境统一管理势在必行。在金门和厦门海洋管理部门之间建立协商和协调机制的时机已经基本成熟,如能积极主动地进行双方沟通和协商。便可以实现金-厦海域环境的全面管理和统一管理。  相似文献   
874.
This study analyzes how overall changes in political and economic life during the last decade have affected the Estonian coastal fishery of the Baltic Sea. At the beginning of the nineties, the opportunity to export fish to the European market emerged. Opening of this new market resulted in rapidly increasing pressure on fish stocks. Some of the most important coastal fishery resources were over-fished because of high export market demand coupled with insufficient resource management and ineffective control and enforcement mechanisms. The costs associated with fishery have grown much more than the first-buyer prices. Additionally, dynamic development of the Estonian economy has resulted in substantial increases in earnings in other economic sectors and therefore the relative wealth of fishermen has steadily declined. This has resulted in increasing social problems. In conclusion, countries in transition may encounter serious difficulties in the fisheries sector, arising from privatization and economic reforms, which may affect the fisheries even years after the establishment of new ruling principles.  相似文献   
875.
Systems engineering principles in fisheries management   总被引:3,自引:0,他引:3  
Ingrid Bouwer Utne   《Marine Policy》2006,30(6):624-634
Fisheries management receives valuable, but often fragmented information from academic disciplines such as biology, economics, and social sciences. A multi-disciplinary perspective seems to be necessary if the fisheries are to become sustainable. Globally, overcapacity is considered as the most serious threat to sustainable fisheries, which indicates the need for a stronger integration of technological aspects into fisheries management. This paper discusses application of systems engineering principles and integration of technology into fisheries management. The systems engineering process facilitates implementation of multi-disciplinary information from researchers to fisheries managers in the decision-making towards sustainable fisheries, but may also be used to overcome multi-disciplinary obstacles among scientists. The article concludes that use of systems engineering principles may become a valuable contribution to fisheries management because of increased transparency and reduced risk associated with the decision-making process.  相似文献   
876.
U. Tietze 《Marine Policy》1984,8(4):330-336
This article considers the development of small-scale fisheries in southern Asia. It outlines a training and visit system that has been widely used in agricultural extension work, and suggests how such a system could be applied to fisheries. Extension workers not only give technical advice, but they attempt to change sociocultural attitudes that impede development. The author describes how a fisheries extension service should be organized.  相似文献   
877.
Cheating about the cod   总被引:1,自引:0,他引:1  
The Northeast Arctic cod is managed by a total quota shared evenly between Norway and Russia. It appears that Russia has been overfishing its quota by substantial amounts for a number of years, due to insufficient monitoring of fishing vessels. This paper considers what would be the best reply by Norway to given levels of Russian overfishing. It is found that in most cases the best Norwegian reply would be also to overfish its quota. An aggregate biomass model with stochastic growth and recruitment is used to analyze this question, with parameters estimated from 1946 to 2005 data. Recruitment is serially correlated but apparently independent of the spawning stock. A model using the estimated serial correlation in recruitment and a random disturbance is capable of reproducing recruitment patterns similar to the irregular pattern observed since 1946.  相似文献   
878.
Chile's new Management Area system delegates management responsibility to organizations of artisanal shell-fishers on the condition that they team with professionally trained marine biologists. A survey of participating fishers in Chile's Fourth and Fifth regions examined four social benefits predicted to result from this type of co-management: (1) improved rapport between fishers and the state, (2) greater awareness among fishers of ecology and the benefits of management, (3) cooperation between fishers and scientists, and (4) unity between fishers. A discussion analyzes the principal benefit encountered—fishers’ newfound “consciousness” of the value of management—within the context of co-management and territorial use rights.  相似文献   
879.
This study describes variability in the marine ecosystem of Ghana, West Africa, on several temporal and spatial scales and discusses how the human communities using this ecosystem respond to this variability to cope socially and economically. Ghanaian marine waters are part of an upwelling system with strong seasonal and inter-annual variability. Much of this variability is forced at large spatial scales in the tropical Atlantic and by El Niño—Southern Oscillation events in the Pacific Ocean, which influence inter-annual variability of sea surface temperature and pelagic fish landings off Ghana. At decadal scales, Ghanaian marine waters experienced cool sea temperatures and low fishery landings during the 1960s, rapid warming and increases in fishery landings during the late 1970s and 1980s, and variable temperatures and fishery landings during the 1990s. In the late 1990s, pelagic and demersal fish populations appeared to be declining, partly due to over-fishing, although the per capita supply (domestic production plus net imports) of fish was kept high by increased imports. Artisanal fishers and fishing communities in Ghana have devised strategies to deal with variability on seasonal and inter-annual scales. These livelihood strategies include: (i) exploiting marine and terrestrial natural resources more intensively, initially at local scales but expanding to regional scales; (ii) ensuring multiple and diversified income sources; (iii) investing in social relationships and communities for support; and (iv) undertaking seasonal or permanent migrations. In addition, the national government imports fish to deal with shortages. However, these strategies may be less adapted to variability at decadal scales, and may not be sustainable when viewed at the larger scales of environmental change.  相似文献   
880.
This paper examines ways to reduce conflicts and improve the sustainability and value of marine recreational fisheries by fully integrating the recreational sector into the management of fisheries. One possibility involves a novel approach, here called angling management organizations (AMOs), which combines three of the more pervasive and promising trends in fishery management worldwide—management devolution, strengthened harvest rights, and co-management. AMOs are community-based organizations that are designed to conform to seven basic principles of integrated fishery management, which are described below. AMOs are loosely related to rights-based producer organizations in commercial fisheries, and are expected to strengthen resource stewardship, reduce enforcement and monitoring costs, alleviate management conflicts, and produce greater long-term net economic benefits in recreational fisheries. The other organizational structures considered here, including the management status quo, do not conform to all seven principles and are not expected to be as effective as AMOs.  相似文献   
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