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71.
《Marine Policy》2017
The growing literature on individual transferable quotas (ITQs) and on intensive salmon aquaculture and its negative impacts on the environment and other users of related marine space has been little connected to the developing literature on financialization and to the literature on ocean grabbing within fisheries. This paper seeks to address this gap through a case study of the recent history of herring fisheries and intensive aquaculture in New Brunswick, Canada, exploring how specific neoliberal processes – including privatization and marketization (in herring fleet ITQs and aquaculture lease systems), (re)regulation, financialization and globalization – have interacted to support the reshaping of regional fisheries from mixed small-scale, family-based, petty commodity fisheries towards vertically-integrated, corporate, financialized fisheries characterized by ocean grabbing. 相似文献
72.
Yuichi Miyake Qinting Jiang Wang Yuan Nobuyasu Hanari Tsuyoshi Okazawa Barbara Wyrzykowska Man Ka So Paul K.S. Lam Nobuyoshi Yamashita 《Marine pollution bulletin》2008,57(6-12):357
Dietary intake is one of the important routes of human exposure to brominated flame retardants (BFRs) such as polybrominated diphenyl ethers (PBDEs). The use of PBDEs may also result in exposure to polybrominated dibenzo-p-dioxins and dibenzofurans (PBDDs/DFs), as these compounds are impurities in technical mixtures of BFRs and can also be formed unintentionally by the same processes that generate chlorinated dioxins. This study determined the concentrations of polybrominated compounds in common seafood in Guangzhou and Zhoushan, and assessed the health risks of these chemicals via consumption of contaminated seafood. Seafood samples (fish, bivalves, shrimp, crab, and cephalopods) purchased from local markets in 2003 and 2004 were analyzed for PBDEs and PBDDs/DFs. The highest concentration of total PBDEs (46.3 ng g−1 lipid wt.) was detected in fish from Guangzhou, in which BDEs 47 and 209 were the two predominant congeners. The total daily intakes of PBDEs, PBDDs, and PBDFs were, 946, 6.39, and 6.54 pg kg−1 body weight (bw) in Guangzhou, and 489, 4.99, and 7.65 pg kg−1 bw in Zhoushan, respectively. The hazard ratios for PBDDs and PBDFs were both greater than unity, indicating that these compounds may pose some health risks to the local population. 相似文献
73.
基于南四湖湖区2006~2016年的水质监测数据,选取CODcr、TP、TN、和NH_3-N作为水质评价指标,对南四湖各湖区的污染情况及年际变化趋势进行对比分析,并利用综合水质标识指数法,对南四湖水质变化年际趋势进行综合评价。结果表明:2006~2016年间,各监控站点CODcr、TP、TN和NH_3-N浓度的年平均值总体呈下降趋势,其中NH_3-N的浓度平均值下降率最大,为72%。2016年南阳湖、独山湖、昭阳湖、微山湖的综合水质指标分别为4.096、3.446、3.350、3.128,呈现出北高南低的空间分布特征。2006~2016年间南四湖的综合水质标识指数由4.620下降至3.350,整体提高了1~2个水质类别,水质得到一定改善。由此可见,加强湖泊区域实施"治"、"用"、"保"并举等流域综合治理措施对湖区的治污效果意义重大。 相似文献
74.
As worldwide population continues to grow, so does demand for seafood by consumers. With this trend, interest in sustainably certified seafood is also increasing. The Maine lobster fishery is currently considering certification based on the Marine Stewardship Council (MSC) standard for sustainable and well-managed fisheries. Although certification is argued to provide a market-based incentive to improve sustainable fishing practices, it is a costly and time-consuming process, and often imposes additional requirements on fisheries in order to meet certification standards. To evaluate whether the costs of Maine lobster fishery certification are worth the presumed benefits, lobster industry members were interviewed to learn their opinions of MSC certification, seafood consumers were surveyed to understand their attitudes and purchasing preferences related to lobster, and lessons learned from other MSC-certified fisheries were compiled. MSC certification of the Maine lobster fishery could potentially provide benefits to the industry by differentiating Maine lobster and maintaining access to markets that are looking to exclusively source certified fish products. However, certification is unlikely to provide price premiums for the fishermen, and does not necessarily represent to consumers the most desirable aspects of Maine lobster. Certification programs may need to adapt to consumer preferences and market conditions if they are to continue to provide incentives for the sustainable management of fisheries. 相似文献
75.
This paper describes the marine fish and invertebrate consumption in three of the world’s major seafood markets (the EU, Japan and the USA) using a series of global maps indicating the likely origin of the seafood consumed by each market. These maps display a high level of dependence by these markets on foreign sources as the serial depletion of local fisheries resources forced the fleets in search for new seafood supplies well beyond their domestic waters. The acquisition of foreign (and high seas) seafood by these markets is conducted through two channels: by dispatching distant water fishing fleets that directly exploit foreign stocks; and by importing catch landed elsewhere by local fleets. The results also demonstrate that each of the three major markets occupies a zone of influence within which it is dominant. 相似文献
76.
本研究以淡水天然水体主要放流鱼类鲢鱼种为实验材料,采用盐酸四环素(TCH)浸泡和药饵投喂两种方式对鲢进行荧光标记,比较这两种TCH处理方法对鲢微耳石的标记效果;测定150、250和350mg/L的浓度条件下浸泡24h鲢血液转氨酶以及肝脏氧化损伤和抗氧化指标的变化。结果显示, TCH浸泡处理比投喂处理对耳石的标记效果更好,在150—350mg/L浓度范围内,浓度越高标记效果越好;TCH浸泡处理24h会引起鲢血清的谷草转氨酶(AST)、谷丙转氨酶(ALT)活性在处理后1d显著升高,2d后降低到对照水平。肝脏氧化损伤指标丙二醛(MDA)水平,抗氧化酶超氧化物歧化酶(SOD)和过氧化氢酶(CAT)活性均呈现先快速极显著升高,然后下降直至恢复正常水平。表明TCH浸泡对鲢肝脏造成了短暂的功能异常和氧化应激胁迫,但在2—5d后即可恢复正常,TCH浸泡方法是鲢标记放流有效、安全、可靠的方法。本研究结果可为鲢的增殖放流、跟踪监测和效果评估工作提供技术支撑,为其他鱼类的标记放流提供参考。 相似文献
77.
Micronutrient deficiencies constitute a pressing public health concern, especially in developing countries. As a dense source of bioavailable nutrients, aquatic foods can help alleviate such deficiencies. Developing aquaculture that provides critical micronutrients without sacrificing the underlying environmental resources that support these food production systems is therefore essential. Here, we address these dual challenges by optimizing nutrient supply while constraining the environmental impacts from aquaculture. Using life cycle assessment and nutritional data from Indonesia, a top aquaculture producer, we sought to identify aquaculture systems that increase micronutrient supplies and reduce environmental impacts (e.g., habitat destruction, freshwater pollution, and greenhouse gas emissions). Aquaculture systems in Indonesia vary more by environmental impacts (e.g. three order of magnitude for fresh water usage) than by nutritional differences (approximately ± 50% differences from mean relative nutritional score). Nutritional-environmental tradeoffs exist, with no single system offering a complete nutrition-environment win–win. We also find that previously proposed future aquaculture paths suboptimally balance nutritional and environmental impacts. Instead, we identify optimized aquaculture production scenarios for 2030 with nutrient per gram densities 105–320% that of business-as-usual production and with environmental impacts as low as 25% of those of business-as-usual. In these scenarios Pangasius fish (Pangasius hypophthalmus) ponds prove desirable due to their low environmental impacts, but average relative nutrient score. While the environmental impacts of the three analyzed brackish water systems range from average to high compared to other aquaculture systems, their nutritional attributes render them necessary when maximizing all nutrients except vitamin A. Common carp (Cyprinus carpio) ponds also proved essential in maximizing zinc and omega n-3, while Tilapia (Oreochromis niloticus) cages were necessary in optimizing the production of calcium and vitamin A. These optimal aquaculture strategies also reduce business-as-usual demand for wild fish-based feed by 0–30% and mangrove expansion by 0–75% with no additional expansion into inland open waters and freshwater ponds. As aquaculture production expands globally, optimization presents a powerful opportunity to reduce malnutrition rates at reduced environmental impacts. The proposed reorientation promotes UN sustainable development goals 2 (zero hunger), 3 (health), 13 (climate action) and 14 (life under water) and requires concerted and targeted policy changes. 相似文献
78.
79.
Caswell JA 《Marine pollution bulletin》2006,53(10-12):650-656
Reducing marine-based public health risk requires strict control of several attributes of seafood products, often including location and conditions of catch or aquaculture, processing, and handling throughout the supply chain. Buyers likely will also be interested in other attributes of these products such as eco-friendliness or taste. Development of markets for improved safety, as well as for other quality attributes, requires an effective certification and tracking of these attributes as well as their communication to buyers. Several challenges must be met if labeling, particularly consumer labeling, is to support the development of markets for improved seafood safety. 相似文献
80.
Todd EC 《Marine pollution bulletin》2006,53(10-12):569-578
Surveillance systems for foodborne disease vary in capacity by country, especially for marine-related illnesses. Generally, the more developed the country is, the more funding that is put into its surveillance programs, but no country has an outstanding system that could serve as a model for all others. An additional problem is lack of consistency. Approaches to surveillance and available resources change over time, so that apparent trends may reflect more of an administrative function. Most countries have some passive system that allows data on foodborne illnesses to be sent to centralized authorities where summaries are generated. However, these depend on the uneven quality of the source data that vary according to the resources allocated at the local level. Active surveillance systems collect data targeted to answer specific epidemiological questions more efficiently, but at such a high cost that most countries do not have the resources, except on a occasional basis. There is also the issue of what to do with the collected data. There has to be a conscious effort to translate the problems identified from the surveillance programs to consider strategies for prevention and control of foodborne disease. Otherwise, there is little value in having these kinds of monitoring programs. Another problem is lack of coordination in surveillance systems between most countries, so that information can be rapidly and efficiently shared. That being said, surveillance over the years had generated much interesting information on how disease agents are transmitted through the food supply, and where contamination and growth by pathogens in the food production and preparation chain typically occur. In addition, attempts are being made to create regional networks in different parts of the world usually initiated by organizations like WHO and PAHO. The kinds of information collected and programs being introduced are discussed in examples taken from both the developed and less developed world, followed by a series of recommendations for improving surveillance on a global basis. A recent burden in the surveillance system is the potential for a deliberate attack on the food supply with agents not usually involved with foodborne illness. At least in the US, a major concern is for the rapid detection and containment of a massive contamination of the food supply. 相似文献