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1.
Portugal has the third highest seafood consumption per capita in the world and current patterns of seafood consumption are linked to how seafood products were embodied in the Portuguese society. The objective of this research is to understand Portuguese seafood consumption's main drivers and its consequences. For that official statistics were analyzed and a literature review on seafood consumption was undertaken. Portuguese seafood consumption is characterized by a wide diversity of species and preparing modes, when compared to other countries in Europe. Cod (salted and dried), does not exist in Portuguese waters but due to several factors, such as politics, religion and tradition, became the main species in Portuguese seafood consumption, representing around 38% of the national seafood demand. Five drivers are suggested to explain why Portuguese eat so much seafood: geography, marine resources, fisheries, social forces and politics; and consequences for the environment, economy and health are discussed. Hence while most dietary recommendations advise an increase in fish consumption is not applicable to Portugal and a more sustainable seafood consumption for the future is advocated.  相似文献   

2.
As the global trade and market for seafood has grown, so have the twin problems of renaming and mislabeling. Resource scarcity, the potential for greater profits, and weak legislation have all encouraged incorrect labeling, the results of which include consumer losses, the subversion of eco-marketing, further degradation of fisheries resources, and even adverse effects on human health. This paper examines the extent and consequences of renaming and mislabeling seafood, the state of current legislation, and the importance of future policies, with particular attention to the US, where 80% of the seafood is imported and more than one-third of all fish are mislabeled. Policy recommendations include governments’ support for a global mandate to label species, country of origin, and catching or production method on all seafood with high penalties for infractions. Chain of custody standards, such as those recently implemented by the Marine Stewardship Council (MSC), should also be considered for adoption worldwide. To garner support for this legislation, consumers must become better acquainted and concerned with their seafood and its origins.  相似文献   

3.
Sourcing seafood for the three major markets: The EU,Japan and the USA   总被引:1,自引:0,他引:1  
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   

4.
The recent overexploitation of East Atlantic and Mediterranean bluefin tuna stock has been well documented in the media where it has become the archetype of overfishing and general mis-management. Beyond the public debate, the crisis also highlighted how the interactions between science and management can change through time according to the awareness of the public opinion. To reflect these issues, the history of Atlantic bluefin tuna overfishing is first described. Then, the major uncertainties that undermine the current scientific advice are summarized and the importance of reducing their impacts by improving knowledge and developing robust scientific framework is considered. The study also discusses how uncertainty was used by different lobbies to discredit science-based management. The recent improvement in bluefin tuna stock status following the implementation of the rebuilding plan shows that, despite uncertainty in the scientific advice, the management of a heavily exploited fish stock can be positive when there is a political will. However, optimizing long-term yields of modern fisheries implies good science. The study concludes by advocating for the implementation of a scientific quota that should be part of the management framework to support the scientific advice.  相似文献   

5.
6.
This paper explores the effects of non-tariff measures (NTM) on extensive and intensive margins of global exports of seafood in 1996–2011. The main result of this study is the differential and opposite effect of SPS and TBT measures. While SPS measures largely increase extensive margins of export and reduce intensive margins, TBTs mostly reduce exports at extensive margins and increase exports at intensive margins. Specific trade concerns (STC) have larger effect on exports than SPS and TBT notifications, both economically and statistically. Finally, there is substantial heterogeneity of response of exports to NTMs across HS six digit product lines, but the central tendency remains the same as for aggregated data.  相似文献   

7.
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   

8.
In the Shenhu area of the northern South China Sea (SCS), canyon systems and focused fluid flow systems increase the complexity of the gas hydrate distribution in the region. It also induces difficulties in predicting the hydrate reservoir characteristics and quantitatively evaluating reservoir parameters. In this study, several inversion methods have been executed to estimate the velocities of strata and gas hydrate concentrations along a profile in the Shenhu area. The seismic data were inverted to obtain the reflection coefficient of each stratum via a spectral inversion method. Stratigraphic horizons were then delineated by tracking the inverted reflectivities. Based on the results of spectral inversion, a low-frequency velocity field of the strata was constructed for acoustic impedance inversion. Using a new iterative algorithm for acoustic impedance inversion, reflection coefficients were converted into velocities, and the velocity variations of the strata along a 2D seismic line were then obtained. Subsequently, gas hydrate saturations at well SH2 were estimated via the shale-corrected resistivity method, the chloride ion concentration method and three different rock physics models. The results were then compared to determine the optimal rock physics model, and the modified Wood equation (MWE) was found to be appropriate for this area. Finally, the inverted velocities and MWE were used to predict the distribution and concentrations of gas hydrates along the seismic line. The estimated spatial distribution of gas hydrates is consistent with that from sonic logging and resistivity data at well SH2, and with the drilling results. Therefore, this method is applicable in areas with no well data, or with few wells, and provides an effective tool for predicting and evaluating gas hydrates using seismic data.  相似文献   

9.
Wrench motion is relatively common in basins but often goes undetected because of its subtle structural imprint. Even so wrench-related folding is of significance in petroleum exploration and development. Based on the Riedel shear nomenclature, we apply the model of wrench-related folding to deformation in the Bohai sea basin. The folding related to R-shears, T-tensional structural systems (T-systems) and C-compressive structural systems (C-systems) in a Riedel shear model are discussed. The R-system related folding results from differential movements between the two sides of fault blocks, in map view the fold is oriented (90°-φ/2) (in the initial deformation stage) or more than (90°-φ/2) from the principle displacement zone (PDZ), where φ is the angle of internal friction. The T-system related folding is related to the rollover of the hanging wall, and in map view the fold is initiated at 45° from the PDZ in the initial deformation stage. The C-system related folding is resulted from the compression induced by a wrench action, in map view the fold was oriented 45° from initial deformation in the PDZ. Bohai Sea basin fold orientations fit our models, and the wrench-related folds play important roles in oil and gas accumulation.  相似文献   

10.
In the maritime sector, seafaring has been predominantly a male industry. The industry had developed its own culture which denied or precluded women's participation. This paper draws on the data and analysis of the Gender, Empowerment and Multi-cultural Crew (GEM) Project, an international study aiming to examine seafarers’ welfare, focusing on gender issues arising from a multi-cultural crew environment in three countries: China, Nigeria and the UK. The main research findings, which relate to China, are reported under the headings of motivation, training, employment opportunities and barriers, and career prospects for women. The paper concludes with a discussion on an important new state policy concerning gender equality in university recruitment and with recommendations to move things forward.  相似文献   

11.
国际海上救援效率比较研究 ——以东海特定水域为例   总被引:1,自引:0,他引:1  
林婉妮  王诺 《海洋通报》2019,38(4):438-446
为研究东海海域海上救援效率和国际协作的协调性,以国际救援为视角,基于ArcGIS构建了海事救援效率评价模型。根据巡逻船舶密度数据确定了救援船舶的概率分布,得出了救援船舶与遇险船舶的可能距离,同时考虑了风浪影响下遇险船舶的漂移以及巡逻船舶失速的情况,分别计算了常风向和次常风向下中国、日本和韩国在东海特定水域的海上救援效率。结果表明:以各国现有的巡逻船舶配备对研究区内漂移的遇险船舶展开救援时,常风向下先后抵达的顺序为韩国、日本和中国,驰援时间分别为5.14、8.18和9.67 h;次常风向下抵达的顺序为韩国、日本和中国,驰援时间分别为5.45、8.25和10.08 h;为提高我国的救援效率,需要在东海海域部署9~10艘巡逻船舶开展常态化巡逻。本文研究可为我国有关部门科学制定和完善海上救援方案,调整海上救援力量配备,进一步加强国际间的协调与合作提供参考。  相似文献   

12.
We measured the absorption coefficients of suspended particles (ap(λ)) during three cruises from coastal waters to open ocean in the northern South China Sea (NSCS). The absorption contributions of phytoplankton (aph(λ)) and nonalgal particles (aNAP(λ)) were determined using the methanol extraction method. Based on the dataset of about 360 samples, we examined the spectral relationships of the particle absorption coefficients. The results show that ap(λ) spectra are well linearly correlated with ap(443) over the wavebands between 420–650 nm; aph(λ) could be well expressed as the second-order quadratic equations of aph(443) among the blue-green wavebands, and aNAP(λ) follows the general exponential function. Based on these spectral relationships, a model was proposed for partitioning the total particulate absorption coefficients into the contributions of phytoplankton and nonalgal particles using the nonlinear optimization method. The model was validated by comparing the computed results with in situ absorption coefficients. In some wavebands, such as 412 nm, 443 nm, 490 nm and 683 nm, we obtained good correlations with the percentage root mean square error (RMSE) values being controlled within 25% and the slopes being closer to 1.0. For samples from coastal waters, the discrepancy was a little large, which might be due to the higher absorption contributions from certain pheopigments. Overall, this model provides us much insight into phytoplankton absorption retrieval from in situ measurements and remote sensing ocean color data.  相似文献   

13.
采用14C与15 N核素示踪方法,于2008年12月—2009年1月对东海和南海北部海域的初级生产力和新生产力的分布进行了研究,并对其环境制约机制进行了初步探讨。结果表明:调查海域叶绿素a质量浓度在空间分布上呈近岸高、外海低,表层高、真光层底部低的分布趋势。东海海域的积分初级生产力(IPP)和积分新生产力(INP)均低于南海北部海域,f比值为东海海域>南海北部海域,东海海域新生产力(NP)对初级生产力(PP)的贡献大于南海北部海域。浮游植物对氨盐的吸收速率(ρNH4)显著大于对硝酸盐的吸收速率(ρNO3)(P<0.05)。水柱平均新生产力与环境参数的相关性分析结果表明,营养盐是影响冬季调查海域新生产力的主要因素,温度和盐度为次要因素。  相似文献   

14.
This study examines a Kuroshio main path(KMP) cut-off event east of Taiwan Island occurred in fall-winter2013–2014 and its impacts on the South China Sea(SCS) by analyzing satellite altimetry and mooring observations. Satellite altimeter sea level anomaly(SLA) images reveal a complete process that a huge cyclonic eddy(CE) from the Pacific collided with the Kuroshio and the western boundary from 15 October 2013 to 15 January 2014. Mooring observations evidenced that the Kuroshio upper ocean volume transport was cut off more than 82% from 17×106 m~3/s in September to 3×106 m~3/s in November 2013. The KMP cut-off event caused the Kuroshio branching and intruding into the SCS and strengthened the eddy kinetic energy in the northern SCS west of the Luzon Strait. Using the total momentum as a dynamic criterion to determine the role of eddy collision with the Kuroshio reasonably explains the KMP cut-off event.  相似文献   

15.
采用国际通用的方法研究了东海近海水质活性磷测定中的不确定度,分析了现场特定环境、测量标准、取样体积、摩尔质量等因素对测量不确定度的影响,评估了各参数的标准不确定度、合成标准不确定度和扩展不确定度.结果表明,现场特定环境是影响东海近海水质活性磷测定中不确定度的主要因素;东海近海水质活性磷测定中的相对合成标准不确定度约为0.067.  相似文献   

16.
海洋涡旋作为一种快速连续变化的海洋现象,如何分析和挖掘其移动特征成为当前海洋涡旋定量研究的重点。本文引入空间数据挖掘的社区网络划分方法,将涡旋过程看作复杂的移动网络,对涡旋移动的聚集性特征进行探索和分析。首先,以网格为统计单元对1992-2011年近20年南海海洋涡旋移动数据进行组织,基于图论模型构建了涡旋瞬时移动(TP),涡旋移动起止点(OD),涡旋最小描述距离的特征点移动网(MDL)和涡旋过程移动再生数据(RSP)4种状态的海洋涡旋的移动网络图;其次,采用基于快速模块度优化的区域划分方法分别得到4种状态下涡旋移动的聚集性区域;最后,利用弦图对区域内和区域间涡旋移动规律进行了可视化分析,发现海洋涡旋的RSP数据能够弥补原始涡旋移动数据在区域划分方法中呈现的数量不足的问题,能够在足够数据量的情况下,有效地发现从起点到终点的主要移动通道和涡旋移动的聚集性区域,这些区域反映了南海涡旋从其产生、发展到结束整个演化过程的聚集性特征。  相似文献   

17.
盒管藻科Capsosiphonaceae由Chapman[1](1952)建立,隶属于绿藻门石莼目Ulvales,目前仅包括1个海藻属即盒管藻属Capsosiphon Gobi[2](1879)。Setchelletal.[3](1920)、Chapman[4](1956)、Bliding[5](1963)、Chihara[6](1967)、Vino-gradova[7](1974)、Garbaryetal.[8](1982)报道过此属的物种。  相似文献   

18.
Researches on the currents in the South China Sea (SCS) and the interaction between the SCS and its adjacent seas are reviewed. Overall seasonal circulation in the SCS is cyclonic in winter and anticyclonic in summer with a few stable eddies. The seasonal circulation is mostly driven by monsoon winds, and is related to water exchange between the SCS and the East China Sea through the Taiwan Strait, and between the SCS and the Kuroshio through the Luzon Strait. Seasonal characteristics of the South China Sea Warm Current in the northern SCS and the Kuroshio intrusion to the SCS are summarized in terms of the interaction between the SCS and its adjacent seas.  相似文献   

19.
通过对福建省厦门湾、闽江口海域、三沙湾三个主要河口海湾144个站位表层沉积物样品中甲藻休眠孢囊的系统分析,根据甲藻休眠孢囊的形状、外壁结构、颜色、表面修饰物等形态特征共鉴定出9属25种及不定种,并对各孢囊属种的特征进行了分类描述,其中有毒甲藻休眠孢囊2种,即Alexandrium minutun,A. tamarense, 有害种类4 种, 即Alexandrium affine,Lingulodiniumpolyedrum,Scrippsiella trochoide.通过对比表明Alexandrium affine,A. minutum,Diplopelta cf. parva,Polykrikos cf. schwartzii,Protoceratium reticulatum,Protoperidinium minutum,P.cf. minutum,P. cf. americanum以及Alexandrium sp.,Protoperidinium sp.1,P. sp.2等11种甲藻休眠孢囊为本次在福建省海域新发现的种,这些新发现的甲藻种类可能是近年来通过国际间往来的航运船只在我国沿岸海域排放压舱水或贝类引种带来的.  相似文献   

20.
南海海盆海山古地磁及海盆的形成演化   总被引:7,自引:0,他引:7  
根据海山磁性反演获取的古地磁成果发现,南海海盆东部和西南部的运动形式、生成时代存在很大差异,东部海盆和西南部海盆之间由一条北北西走向的岩石圈压性左旋转换(性)断层——"南海海盆中央断裂"分界.结合已有的地质地球物理成果分析和论证,确定了南海海盆在古南海和与之接壤的华南地块南部边缘形成.南海海盆的形成演化分四个阶段:第一阶段,始新世"古南海断裂"产生,古南海被一分为二;第二阶段,渐新世东部海盆开始发育——扩裂;第三阶段,中中新世西南部海盆开始发育——张裂;第四阶段,南海海盆整体旋转,古南海圈闭.  相似文献   

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