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101.
我国是世界最大的养殖用海国家,养殖用海不但影响人民自身利益和社会的和谐稳定,并且也关系到沿海地区的经济发展。当前,我国养殖用海在自然资源统一管理和生态文明建设的新形势下存在规划繁杂重叠、环境污染、产权制度不完善等问题。文章将从养殖用海历年确权及注销面积和当前养殖用海管理现状出发,阐述我国当前养殖用海面临的问题,找出养殖用海空间保障不足的原因,并依据我国当前养殖用海管理所处的形势,提出了划定养殖用海基准线、编制“多规合一”下的养殖用海专项规划、施行养殖用海用途管制和整治修复、加强养殖用海监督管理等建议,解决当前养殖用海问题。  相似文献   
102.
Experiments on wave transmission coefficients of floating breakwaters   总被引:1,自引:0,他引:1  
To find a simple, inexpensive, and effective type of floating breakwater for deep-sea aquaculture, we studied three types of structures: the single box, the double box, and the board net. We conducted two-dimensional physical model tests in a wave-current flume in the laboratory to measure the wave transmission coefficients of the three types of breakwaters under regular waves with or without currents. Based on the initial comparison of the wave transmission coefficients, we proposed the use of the board-net floating breakwater for use with fish cages; we then conducted detailed experiments to examine how wave transmission coefficients are affected by several factors, including the width of the board, the row number of the net, the rigidity of the board, and the current velocity. The experimental results show that the board-net floating breakwater, which is a simple and inexpensive type of structure, can effectively protect fish and fish cages and may be adopted for aquaculture engineering in deep-water regions.  相似文献   
103.
红海湾海水养殖水域的营养盐、盐度、温度、浮游植物和叶绿素的观测结果表明,该水域中氨氮、亚硝酸盐及磷酸盐的消长受水系混合所制约。春季硝酸盐、氨氮和秋季磷酸盐与浮游植物之间存在着负相关,秋季表层叶绿素与营养盐(除氨外)存在着正相关,而底层叶绿素与营养盐存在密切负相关  相似文献   
104.
This paper presents an analytical solution for scattering of oblique incident, small amplitude, monochromatic wave trains by a stationary rigid multi-layered objects with rectangular cross-section. The object is infinite long and consists of multilayers, which can be either solid or permeable. This paper extends the previous work by Hu and Liu [1] from normal incident wave condition with a special object configuration to oblique incident waves with multi-layered object. The present model is validated with several existing solutions for normal/oblique waves interacting with a single object; excellent agreement is observed. New numerical results are presented to investigate the effects of incidence angle on reflection, transmission and energy loss coefficients for a combined floating and bottom-mounted permeable breakwater. A new floating board-cage breakwater is developed from the present model and its solutions are discussed in detail. A computer program, AWAS-P, has been updated so that it is applicable for both oblique and normal incident waves, while the object is multi-layered.  相似文献   
105.
Aquaculture activities have introduced European sea bass (Dicentrarchus labrax) along the coasts of some of the Canary Islands. We present the first record of simultaneous male and female gonad maturation of escaped sea bass in the wild, indicating that this species is finding its essential fish habitat (EFH). Individuals with ripe gonads were only caught during January and February 2009, although the maturation and spawning season may last from November to February in the studied area (Tenerife island). Bass infected by Sphaerospora testicularis were found and the incidence of the parasite was checked. This represents the southernmost record of the parasite, probably introduced together with sea bass stock. The results are discussed from the point of view of risk assessment and the ecology of invasions being valuable for aquaculture management in Central North Atlantic and Mediterranean areas.  相似文献   
106.
Through the case of the salmon aquaculture sector in Chile, the risks involved in the development of a non-traditional export sector are reviewed, in order to point to failings (lessons not learned) and opportunities (lessons learned, new plans), and the changing scales of stakeholder interactions. In particular the paper highlights the ways in which sustainability considerations have gained ground in terms of evaluating sectoral development and what is expected from this development. These considerations have emerged as a result of the increasing globalisation of the sector, through investment, exports and international ‘attention’ from an increasingly diverse set of stakeholders. These sustainability considerations have generated a range of conflicts linked to these diverse actors. The actors are local, national and global, operating through alliances to bring pressure on others. The conflicts relate to environmental quality, foreign direct investment (FDI), local socio-economic development, regional development, national economic strategies, and new globalised issues relating to the production and consumption of foodstuffs. The contemporary panorama in the sector is significantly different from the early origins in the 1980s under the dictatorship – the period of ‘the socio-ecological silence’ – also different from the 1990s period of economic expansion – ‘the economic imperative’. Over the past twenty-five years, the Chilean aquaculture sector has evolved from experimental production to a major global industry. Regulatory frameworks and civil society awareness and mobilisation have struggled to ‘catch up’ with the dynamism of the sector, however the gap has reduced and the future of the sector within the contemporary context of ‘glocal’ sustainability is now under the microscope: the ‘sustainable globalisation perspective’. The collapse of the sector during the period 2008–2010 as a consequence of the ISA virus is a key moment with production severely diminished. The way out of the crisis, via new legislation and inspection regimes, will create a new structure of aquaculture governance. Nevertheless, the crisis marks a turning point in the industry, revealing the weaknesses built into the former productive system.  相似文献   
107.
We report the construction and characterization of a normalized cDNA library from the digestive gland of the marine bivalve Nodipecten nodosus, a commercially valuable tropical scallop. A total of 288 clones were sequenced, and 250 unique sequences were obtained. The cDNA library showed a small sequence redundancy (2.3%) and high numbers of recombinant (99.9%) and independent clones (2.0 × 106 cfu), indicating that the cDNA library generated in this study is a profitable resource for efficient gene discovery for N. nodosus. EST functional annotation by Gene Ontology term assignment revealed the identification of sequences potentially involved in aquaculture and ecotoxicology relevant processes such as apoptosis, growth, lipid metabolism, reproduction, development, response to stress and immunity.  相似文献   
108.
Ecosystem-based management (EBM), despite the best efforts of managers, researchers, and policy makers, often falls short of its intended purpose resulting in inadequate protection of resources. Coastal habitats are particularly vulnerable to poor management due to high use and potential for user conflict. EBM can be improved when it is informed by ecological science and considers the socio-economic needs of the community. Communication between scientists and stakeholders can help to prevent adverse outcomes while enhancing protection and sustainability of the coastal environment. In the research presented here, a framework is used to guide and enhance communication between scientists and stakeholders for sustainable management of resources and equity of all users. The outcome of this applied framework is a long-term plan to guide the management of an oyster aquaculture industry using carrying capacity as an estimate for the basis of management decisions. Central to the framework is the Working Group on Aquaculture Regulations (WGAR), which represents a diverse group of stakeholders. The WGAR worked closely with ecological modelers over a two-year period using mass-balance modeling to calculate ecological carrying capacity for oyster aquaculture in two ecosystems: Narragansett Bay and a set of highly flushed temperate lagoons in Rhode Island, USA. Collaboration between scientists and the WGAR greatly improved the models and stakeholder understanding of the science and acceptance of the results. Aquaculture is increasing in coastal regions world-wide and this framework should be easily transferable to other areas suffering from similar user conflict issues.  相似文献   
109.
The growing aquaculture industry is projected to feature ever more prominently in the lives and economies of rural coastal communities in Atlantic Canada and around the world. Both private industry and government have a responsibility to ensure employment opportunities created in aquaculture take place in healthy, safe environments. However, systematic occupational health and safety (OHS) research within this industry, an important prevention tool, is still in its infancy. With particular emphasis on marine aquaculture in Atlantic Canada, we provide a detailed outline of the structure of the industry from feed production through to processing, identify potential OHS hazards associated with each of these activities and make recommendations for future research and action.  相似文献   
110.
For much of the last century, the prerequisites for establishing a new primary industry were property rights to secure access to the required natural resources, the appropriate technology, brood stock and labour, and a willing investor. In contrast, in many western nations although all these prerequisites have been in place for the establishment of new coastal marine farming sectors, fledgling aquaculture operations have failed to establish. A prime reason for this is that under increasingly consultative integrated coastal zone management regimes, local stakeholders are expressing a desire for prospective aquaculture operations to demonstrate that they will be sustainable. Many potential marine farmers and regulatory authorities have stumbled on this demand and the work presented here aims to elucidate the nature of sustainability in a coastal aquaculture context and provide a framework for investigating these critical ‘non-traditional’ factors limiting the establishment and development of coastal aquaculture activities.  相似文献   
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