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91.
A paper by Pauly and Froese published in Marine Policy includes several misrepresentations concerning a paper published in Nature by Branch et al. on the tropic fingerprint of marine fisheries. The purpose of this Short Communication is to examine and refute their claims.  相似文献   
92.
We investigate the interactions between anthropogenic climate change, socioeconomic developments and tuna fishery management strategies. For this purpose, we use the APECOSM-E model to map the effects of climate change and commercial fishing on the distribution of skipjack tuna biomass in the three oceans, combined with a new bioeconomic module representing the rent or profit of skipjack fisheries. For forcing, we use Representative Concentration Pathway (RCP) 8.5, the highest emission scenario for greenhouse gas concentrations presented in the IPCC’s Fifth Assessment Report (AR5), and the IPCC Socioeconomic Shared Pathway (SSP) 3, which is characterized by low economic development and a strong increase in the world population. We first investigate the impact of climate change on regional skipjack abundance, catches and profits in three oceans (Atlantic, Indian and Pacific) in 2010, 2050 and 2095. We then study the effects of three management strategies (maximum sustainable yield or MSY, maximum economic yield or MEY, and zero rent or ZR) on the future distribution of fishing fleets between oceans and on global economic rent.Our model projections for 2050 and 2095 show an increase in global skipjack biomass compared to 2010 and major changes in its distribution, impacting local and regional fishing efforts. The Pacific Ocean will continue to dominate the skipjack market.In our modeling of management strategies, the currently predominant MSY strategy would have been unprofitable in 2010, due to a decreased catch per unit effort (CPUE). In the future, however, technological developments should increase fishing efficiency and make MSY profitable.In all the scenarios, a MEY strategy is more profitable than MSY but leads to the lowest catches and the highest prices. This raises ethical questions in a world where food security may become a top priority.In the scenarios where MSY generates an economic loss (e.g. 2010), a ZR strategy allows global stocks to be exploited at high but still profitable levels. Conversely, in the scenarios where MSY is profitable, (e.g. 2095) ZR leads to overfishing and smaller global catches.We conclude that the most appropriate management strategy at any time is likely to change as environmental and socioeconomic conditions evolve. The decision to follow one or other strategy is a complex one that must be regularly reviewed and updated.  相似文献   
93.
2007年夏季和秋季,按照GB11607-1989《渔业水质标准》和GB3838-2002《地表水环境质量标准》,对陕西黄河湿地渔业水域环境质量的主要理化指标进行了现场监测,对渔业水域的主要水生植物进行了调查。结果表明:陕西黄河湿地渔业水域的池塘和大水面硫化氢(H2S)含量均符合标准,池塘和大水面的总磷(TP)及总氮(TN)均不符合标准。池塘和大水面渔业水域环境质量呈明显的富营养化现象,池塘比大水面富营养化现象严重,但湿地大水面的主要理化指标优于池塘,湿地大水面渔业水域生长的水生植物芦苇Phragmites australis和香蒲Typha orientalis对TP和TN具有一定的净化作用,通过监测分析提出了湿地渔业水域的保护措施。  相似文献   
94.
Systematic genetic analyses of fish populations allow the testing of temporal stability in their genetic structures and better understanding their pattern of connectivity. In this study the pattern of gene flow between the two Atlantic stocks of the European hake has been examined for the period 2000-2002. Present analyses indicate that a large genetic homogeneity existed among all Atlantic populations in that period, and that a systematic grouping occurred between Porcupine Bank samples and Cantabric ones. This scenario is congruent with an inter-annual gene flow from central grounds of the northern stock (Porcupine and Great Sole) to Iberian grounds inhabited by the southern stock. Additionally, estimated migration figures were in agreement with the good recruitments observed in the southern stock after 2003 despite the spawning biomass was at its historical minimum. Altogether these results highlight the central role of Porcupine bank and Great Sole in making sustainable both stocks and advocate the integrative management of this hake fishery by means of a multidisciplinary assessment.  相似文献   
95.
在海洋渔业中 ,存在着自然状态的不确定性 ,这会引起人的行为的不确定性 ,进而引起资源供给的不确定性。不确定性使渔民对其行为的预期存在风险 ,因而他们总是试图规避风险以减少不确定性带来的损失。人们的风险规避行为可能带来海洋渔业资源过度使用的效应  相似文献   
96.
This interdisciplinary paper presents an empirical analysis of techno-institutional lock-in in a regional fishery, in the Logone floodplain in the Far North Region of Cameroon. In the Logone floodplain, one fishing technique is spreading exponentially even though it is changing the social, hydrological and ecological dynamics of the system in ways that are largely considered problematic by local communities. We use a complex systems framework to analyze large hydrological and socio-economic datasets. Results show how social-ecological feedbacks foster the spread of the technique and contribute to the process of lock-in. The lock-in leads to a resistance to change despite awareness of the technique’s impact, a situation that may also be described as a social-ecological trap. We identify and explain four kinds of positive feedback loops relating to socio-economic, behavioral, demographic and hydrological processes, respectively. We also identify possible solutions that consider the complexity of the feedback loops across multiple dimensions of the floodplain system.  相似文献   
97.
为了维护渔业生产秩序的和谐稳定,实现渔业资源的可持续发展,我国渔业法对诸多不当行为予以规制。但由于渔业法对“情节严重”的表述具有一定的模糊性,未能明显阐明立法者本意,不少渔业行政执法人员对此感到难以认定和把握,为了稳妥起见只追究较轻的责任,如此不利于法律的实施。因此,明确情节严重的认定标准具有重要的理论和实践意义。针对认定标准不明确、行政裁量空间过大、部分执法人员处罚结果不够合理的问题,在考虑我国当前国情的基础上,建议在立法上出台相关的司法解释,行政机关制定完善的行政裁量基准,并辅以司法机关审查作为补充,多元规范“情节严重”的理解与认定。  相似文献   
98.
优质的渔业水域环境是我国渔业可持续发展的重要保障,目前,我国渔业水域环境面临着较为严峻的污染问题,污染事故时有发生,严重影响了渔业的持续稳定发展。为了保护渔业水域环境、防治渔业水域污染事故,我国在《中华人民共和国渔业法》《中华人民共和国水污染防治法》《中华人民共和国海洋环境保护法》等法律中均规定了相关内容,基本形成了渔业水域污染事故的法律规制模式,但仍然存在许多法律问题,如法律规定缺乏实施细则,可行性较低;相关定义模糊不清;事故损害调查方式不够合理等。在此背景下,文章分析了目前渔业水域污染事故对应的民事法律责任、行政法律责任和刑事法律责任,并提出建议,为渔业水域污染事故的处理和归责提供参考。  相似文献   
99.
为提高我国海洋科考船的建造和应用水平,促进远洋和极地渔业发展,文章根据国内外海洋科考船的发展历史和现状,分析我国海洋科考船在海洋渔业发展中存在的问题以及海洋科考船的发展趋势,并提出相关建议。研究结果表明:国际海洋科考船发展早、数量多且装备先进;我国海洋科考船发展较快,但仍需提升数量和技术,在建和研发船舶具有世界领先水平;在促进海洋渔业发展方面,我国海洋科考船存在远洋和极地调查能力以及集成功能较弱的问题;基于海洋科考船在提高极地作业能力等方面的发展趋势以及海洋渔业发展需求,我国海洋科考船的建造和应用应加强顶层设计、技术应用和数据共享。  相似文献   
100.
A critical issue in marine ecosystem-based management is addressing the compatibility of extractive use with ecosystem protection. Analysis of the protected area planning process for the Northwestern Hawaiian Islands suggests the key elements of an ecosystem-based approach to protected area management include establishing a common understanding among decision makers of ecosystem boundaries and ecosystem condition, informed by the best available science. A participatory process is proposed that relies on an informed assessment of whether extractive use compromises ecological integrity and is consistent with conservation objectives. Best practices for compatibility determinations are proposed for multi-agency protected area management and planning.  相似文献   
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