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21.
Drawing on a political economy of food quality, this paper investigates the main sources of uncertainty over the environmental sustainability of Vietnamese pangasius catfish in European markets and how retailers subsequently respond to these uncertainties. Based on media survey and interviews with supermarket retailers across Europe between 2008 and 2010, the analysis focuses on the claims and counterclaims over the sustainability of pangasius aquaculture, how retailers have dealt with the uncertainty these claims have engendered about the fish, and what effect this uncertainty has had on the potential of marketing ‘sustainable pangasius’ in European supermarkets. The paper concludes that successful claims around new food qualities like sustainability by retailers are dependent on the ability of regulatory networks to overcome any perceived illegitimacy of imported products in the face of continuing uncertainty and the wider politics of market protectionism.  相似文献   
22.
The growth of intensive export-oriented Pangasius catfish production in Vietnam’s Mekong Delta is unparalleled in terms of rapidity and scale by any other agricultural sector, with production climbing from a low base to more than 1 million tons in a single decade. This paper examines the effects of this remarkable change on the rural class structure in locations where catfish farming has boomed, and analyses the role of local state-society relations in mediating outcomes resulting from the integration of local actors into the global value chain. We conclude that private economic activity is deeply embedded in informal relations with the state bureaucracy in Vietnam, with the result that the expansion of catfish aquaculture has generally acted to reproduce and entrench existing class relations rather leading to a radical reconfiguration of the rural class structure.  相似文献   
23.
This paper reviews the evidence of the impacts of marine management interventions on human development and well-being reported in marine management literature in the past two decades. Documents dealing with fisheries, aquaculture, marine conservation and coastal zone management are assessed in terms of the methodologies used, the human development dimensions considered, and the results reported. The choice of dimensions for defining human development in this literature is contrasted with proposals from the literature on the capability and human development approaches. Possible areas for future research are discussed.  相似文献   
24.
Fisheries resources play a major role in the national economy and to food security in Solomon Islands. Climate change is likely to have a substantial impact on fish production that can lead to a fragile food security condition in the country. This paper assesses the potential economic impact of three important climate change adaptation strategies – natural resource management (NRM), fish aggregating devices (FAD) and aquaculture – in Solomon Islands. The study used a country-specific partial equilibrium economic model with six fish sub-sectors and analyzed potential impact of alternate climate change adaptation strategies for 2035 and 2050. The modeling and scenario analyses show that total fish demand is likely to surpass domestic fish production in 2050. Without appropriate climate adaptation strategy, per capita consumption of domestically produced fish will decline, which has serious negative food security implications for the country. The economic (welfare) analysis conducted based on modeling results show that the national level net economic gains due to climate change adaptation strategies are substantial. If cost and topographic conditions permit, low-cost inshore FADs are expected to be a good mechanism for augmenting domestic supplies of tuna and similar species in Solomon Islands.  相似文献   
25.
Aquaculture has been the world’s fastest growing food production technology in recent decades, and continued growth in aquaculture production is predicted. While creating economic opportunity, aquaculture is also a new way of using eco-systems, and there is substantial evidence that aquaculture creates negative environmental externalities. Although the most effective way to address these externalities may be improved governance, this approach is often difficult because most aquaculture production takes place in developing countries with limited management capacity. The fact that a large part of aquaculture production is traded motivates substantial interest in the use of trade measures to reduce environmental impacts. However, the wide variety of species, production practices, and governance systems present in aquaculture makes it unlikely that general trade measures will achieve environmental objectives. Rather, there is a real risk that trade measures will reduce economic opportunity, raise new equity concerns, and impinge on public health with little or no environmental impact.  相似文献   
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27.
Marine sediment samples were collected in the Broughton Archipelago, British Columbia, to assess the use of a geochemical normalization technique in the identification of a chemical tracer of aquaculture waste material. Zinc and copper were suggested as tracers of feed pellets, while copper was considered an indicator of anti-foulant agents used on netpen systems. The sediment samples were analyzed for carbon, nitrogen, organic matter, water, trace-element, and free sulfide concentrations, and sediment grain-size distribution. Sediment texture analysis revealed a wide range of substrate types from sand to silty loam categories. Strong relationships between sediment texture, sediment porosity, and organic content were observed across both near-field and far-field stations. Excess zinc and copper sediment concentrations, identified using a lithium-normalization technique, were restricted to near-field sampling stations (0 and 30m from netpen systems). The relationships between these metal tracers and organic content and sulfur concentrations were explored to account for variations in sediment concentrations of zinc and copper.  相似文献   
28.
Perch suffering from swim bladder inflation failure (sinkers) are reported from wild populations of Lakes Constance, Geneva, Lucerne, Sempach, and Zurich in central Europe. Sinkers were found at all 7 locations considered in a survey. Relative abundance of sinkers varied from 0.1% to 7.9% of local perch populations. Sinkers from wild populations and sinkers reared in the laboratory showed similar behaviour and malformations. Information on sinker syndrome in 26 physoclistous species is compiled. It is found to be a widespread problem in aquaculture, but is reported here for the first time from natural populations.  相似文献   
29.
浮游植物初级生产力是评估水产养殖系统结构与功能的基础环节,对渔业资源的开发与管理具有重要意义.于2018年5-10月,采用黑白瓶法对闽江河口区的3个南美白对虾养殖塘(Pond Ⅰ、Pond Ⅱ和Pond Ⅲ)水体浮游植物初级生产力进行了原位监测,初步研究了初级生产力在池塘间的差异性及其时间变化特征.结果显示,养殖期间养...  相似文献   
30.
Worldwide demand for energy is growing and predicted to increase by up to three times by 2050. Renewable energy will play a vital role in meeting this demand whilst maintaining global climate change targets. Around the British Isles, development of wind farms has entered Round three, with large, high capacity wind parks being planned to enhance energy security and achieve 2020 renewable energy targets. Such developments place additional pressure on existing sea space and may result in conflicts with other marine activities and users. Co-location of certain activities, marine protected areas, aquaculture and commercial fishing in particular, has therefore been proposed as an option to ease demands on space. Using the UK guided by EU and regional policy, as a case study, following the criteria-based planning system, co-location is legally feasible. Crucially, co-location options will depend on site specific characteristics and site management plans. The biology, ecology and hydrology of the site as well as consideration of important commercial and economic factors will be determining factors of success. For marine protected areas compatibility with conservation objectives for the site will be fundamental. Where possible, it is suggested that activities suitable for co-location will develop in tandem with renewable energy projects. The importance of developing joint projects in this manner is particularly true for aquaculture projects to ensure tenure security and commercial viability. Adaptive management will be a basis for evolution of the concept and practice of co-location. Pilot projects and continued monitoring will be essential in shaping the future of co-location of activities. As the Marine Management Organisation continues the development of marine plans for the English inshore and offshore waters, a study into potential solutions for resolving sea use conflicts is timely. This paper therefore provides a concise overview of the current regulation affecting co-location of key marine activities within wind farm zones and provides suggestions on how co-location projects can be adopted and taken forward, using the UK as a case study.  相似文献   
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