基于AHP的舟山灯光围网渔船捕捞能力影响因子权重评价

根据3艘舟山灯光围网渔船的生产统计数据,通过层次 分析法(AHP),分析了影响渔船捕捞能力的因子(总吨位、主机功率、作业天数和水下灯功率),并根据各影响因子的重要性确定其权重,建立影响灯光围网渔船捕捞能力的多因子评价模式。结果表明:总吨位对灯光围网捕捞能力的影响最甚,其次是主机功率、作业天数和水下灯功率,其所占权重分别为0. 461 2,0.342 4,0.137 1和0.059 4。     

阿拉伯海鲐鱼渔场时空分布及其与海洋环境的关系

采用2016—2017年中国印度洋围拖网生产数据和同期的海表温度、叶绿素、表层海流和海面高度数据, 绘制了阿拉伯海鲐鱼Scomber australasicus围网月平均单位捕捞努力量渔获量(CPUE)和环境因子空间叠加图, 分析鲐鱼渔场与海洋环境因子之间关系, 采用频次分析和经验累积分布函数计算鲐鱼渔场最适宜的海洋环境区间。结果表明, 该海域月平均CPUE呈现先减少后增加的趋势; 围网渔场渔汛主要在东北季风期间, 从10月到翌年3月; 作业渔场重心分布在59°—62°E、13°—17°N, 具有明显的月变化, 基本呈现西南移动趋势。空间上, CPUE 分布在西边界流速较大的海域右侧, 在海流最大值和最低值中间区域。在印度洋东北季风期间, 阿拉伯海围网鲐鱼渔场适宜海表温度在25~28℃; 叶绿素浓度在0.2~0.5mg·m ^-3; 表层海流在0.05~0.25m·s ^-1; 海表高度0.2~0.35m。     

渔业活动对东海海域海底光缆安全的影响

通过对东海海域海底光缆路由区作业渔场的捕捞方式、作业范围等的分析,结合已建海底光缆故障的调查结果,探讨了渔业活动对东海海域海底光缆路由调查和已建海底光缆安全的影响。结果表明,东海海域海底光缆主要穿越了长江口、江外、舟山、舟外、鱼外等5大主要作业渔场,各渔场的渔业活动频繁,拖网、张网和流刺网等不同捕捞作业方式集中,对海底光缆的安全带来严重威胁。同时,捕捞渔船船只的数量逐年增多、触底深度的不断增加、作业时间的不断延长,使海底光缆路由调查时所获得调查资料的质量受到严重影响,船只、渔具的日益大型化以及拖网、张网、围网等捕捞活动范围的持续扩大,更使得海底光缆的故障频繁发生。为保护海缆的安全,在目前的经济技术条件下,建议选择休渔期时进行路由调查,在捕捞活动的频繁区,选择双层铠装型(DA)的海底光缆,并适当加大埋设深度,以降低渔业活动对海底光缆工程的影响。实践表明,将海底光缆埋设深度增加至3.0 m以上,可有效地保护海底光缆的安全。     

优化操纵渔船主机降低NOx排放的试验研究

通过对东京水产大学研究练习船“神鹰丸”的航速、主机转速、功率及排放废气的测定，得出在各种常用工况下NOx的排放率曲线、等船速曲线和燃油消耗率曲线。分析比较确定NOx的排出率较低，燃油消耗率又不超过规定标准的工况点，从而达到主机优化操纵的目的。结果表明，在自由航行工况下船舶航速为4、8、12、13kn时，主机转速应设定在750r/min；航速为10kn时，应设定在875r/min。拖网及延绳钓作业工况下主机转速应设定在875r/min。     

闽南-台湾浅滩渔场蓝圆鲹种群的年龄结构和生长特性

蓝圆鲹[Decapterus maruadsi(Temminck & Schlegel)]属暖温性中上层鱼类,是闽南-台湾浅滩渔场机帆船灯光围网的主要捕捞对象,也是机帆船底拖网的重要渔获。为探讨本区蓝圆鲹种群结构的资源特点及其数量动态,我们对其种群年龄结构和生长特性进行了分析,从而为制定蓝圆鲹繁殖保护措施以及多种类渔业管理提供依据。一、材料和方法1982年2月至1983年12月,从厦门市海洋渔捞公社灯光围网机帆船的渔获物中,周年逐月收集本区蓝圆鲹的幼鱼和成鱼样本578尾,经生物学测定后,自鱼体左右侧第Ⅴ     

遥感技术在底拖网渔业上应用可能性的探讨

本文通过对目前国内外遥感技术的概述及目前我国机轮渔业渔场的特点来探讨遥感技术在我国机轮底拖网渔业上应用的可能性。 根据我国机轮底拖网渔业渔场的特点——鱼类的垂直及水平集群都和其生活的环境有密切关系,分别对带鱼和马面鱼二大渔期的垂直和水平集群条件加以分析,认为可以通过卫片获取环境因子,并利用其独有的同步性,及时性和完整性的优点来迅速判断渔场环境变化,从而达到指导渔业生产的目的。     

伊朗阿曼湾渔场拖网渔具改进探讨

过洋性渔业是我国远洋渔业的重要组成部分,伊朗阿曼湾渔场是我国新开发的过洋性渔场,单船底拖网是主要的作业方式。文章从过洋性渔业生产的推力、阻力以及过洋性拖网渔具存在的问题出发,分析目前单船底拖网油耗偏高的问题,并针对阿曼湾渔场的特点,在网型、网衣尺寸、网板以及拖网的自动化和智能化等方面进行改进与探讨。同时提出4点建议:提高网口高度,增加侧身力纲;增大网目尺寸和网口周长,确定合理的身周比;采用柔性网板;采用瞄准捕捞技术以及网囊实时监测、自动脱落和提网技术。拖网性能的提高对我国远洋渔业的发展至关重要,对实现海洋强国目标具有重要的战略意义。     

关于我国金枪鱼围网渔业发展问题的几点探讨

本文通过对联合国粮农组织公布的1989－1998年金枪鱼渔获量的分析，清晰了我国发展金枪鱼围网渔业的趋势，并着重对于围网生产密切相关的渔场选择、捕捞技术进行了几点探讨，还对开发科研工作谈了个人看法。     

东、黄海围网渔场鲐鲹鱼产量的年际变动

根据1998～2002年我国主要渔业公司灯光围网船在东、黄海的生产统计资料,利用Marine Explorer4.0软件进行渔场分布绘制和年际比较,利用空间距离聚类法对南、北两大渔场的产量重心年际变化进行比较.结果表明,高产量渔场主要集中在南部的26°～28°N、122°～124°E和北部的32°～38°N、123°～125°E海域.年际间渔场分布及其产量重心有所变动,北部渔场分布范围较大.渔场产量重心分布变化与海洋环境条件存在明显的关系,1998年6～7月由于沿岸冲淡水势力较强,造成了7月份围网渔场产量重心明显向东偏移.     

卫星红外遥感信息与底拖网渔场相关性的初步研究

一、前 言 作为海洋渔业生产的一个重要环节──渔场安排和船只调度合理与否,直接关系到捕捞效果和经济收益,这是海洋捕捞企业生存和发展的前提,然而要合理地作出渔场安排和船只调度,必须对生产海域的海况环境变化及时有所了解,而卫星遥感图象所提供的海况环境要素变化的信息,在同步、及时、宽广性上无疑是得天独厚的,因此引起国内外渔业界的高度重视。美国、日本、加拿大等国已将卫星遥感信息应用于中上层渔业生产,对指导渔民寻找金枪鱼、鲱鱼和鲐黪鱼渔场取得了良好的效果。然而我国目前海洋渔业生产的主要捕捞对象是近底层鱼类,主要作业方式是对船底层拖网。在黄、东海生产的近千艘渔轮,90 ％是从事底拖网作业的,沿岸4万多条群众机帆渔船亦以底拖网生产为主。因此能否在以底曳网生产占主要成分的我国海洋渔业中,应用卫星红外云图提供的遥感信息,是广大水产工作者十分关心的问题。它关系到遥感信息渔业应用的发展前途。 本文目的在于通过对黄、东海海洋环境要素变化特征和卫星红外遥感信息与渔场相关性的分析,论证卫星红外云图在我国底拖网渔业生产中应用的可行性及其作用。     

A letter of clarification from the authors of “trophy fishing for species threatened with extinction”

A rejoinder to our recent paper suggests that there has been confusion over our central point. The 85 IUCN Red List Threatened species that the International Game Fish Association issues world records became threatened due to commercial overfishing, not recreational. However, given that they are threatened now, we have concerns about trophy fishing for them, at least in the current form that precludes catch and release. Additionally, while the IGFA claims that an insignificantly low number of record applications for these species have been submitted, many more anglers attempt to catch a large fish than end up submitting record applications. We are grateful for the opportunity to discuss this important issue.     

The definition of marine recreational fishing in Europe

To describe marine recreational fisheries, their socio-economic importance and interactions with other fisheries and the environment, it is necessary to define what is meant by recreational fishing. A review of European Member States’ national legislation revealed considerable variation in ownership and access to coastal waters/fisheries, and in the legal distinction between sport fishing and other recreational uses of marine fisheries and their commercial (catching for sale and profit) counterparts. Together with a re-examination of existing definitions, this has enabled us to suggest definitions that may be used to develop a common approach to evaluate participation and socio-economic value of marine recreational fishing, and guide attempts to legislate for the benefit and development of marine recreational fishing across Europe.     

黄渤海区捕捞结构的研究

根据2010年对黄渤海沿海32个主要渔港、渔村和5家网具生产厂家的实地调查和现场测量资料,结合2009年度三省一市(河北、辽宁、山东、天津)的渔具渔法调查报告以及1983~2009年中国渔业年鉴中记载的捕捞产量分类统计资料,对黄渤海区捕捞结构进行了研究.研究结果表明,黄渤海区主要捕捞品种有30种之多,其中年渔获量超过万吨的有14种鱼类、5种甲壳类、4种头足类、2种海蜇和6种贝类.渔业资源品种的多样性决定了黄渤海区捕捞结构的多样化和多层次的特点,现有9大类19型23式130种网型或作业方式,同时受渔业资源变动的影响,捕捞网具也在变化,不断有旧的渔具消失和新的网具出现.其中,拖网是主要作业方式,贡献率为38.47%~51.79%,且近几年还有上升的趋势;其次为刺网,贡献率从1983年最低时的7.66%逐步上升到目前的30.14%;第三为张网,贡献率从1985年最高时的34.31%下降到目前的10.49%;围网和钓具的贡献率一直较低,均不足4%,其他渔具的贡献率为5.98%~13.30%.目前黄渤海区渔业结构的调整方向应当是减少拖网作业,控制刺网总量,限制张网、陷阱类渔具和地笼,鼓励发展钓渔业     

Linking fishery management and conservation in a tropical estuarine lagoon: biological and physical effects of an artisanal fishing gear

Information coming from fishery monitoring, surveys and experimental fishing with participation of fishers was employed to determine the impact of an artisanal gear, ‘boliche’, on the biodiversity of the Ciénaga Grande de Santa Marta (CGSM), an estuarine lagoon on the Caribbean coast of Colombia. Fishery monitoring (catch data) included landings before (1968 and 1978) and after (1994–1996) the introduction of the boliche in the CGSM (1985), whereas surveys were conducted seasonally during 1993–1994. Fishing experiments involved evaluating different mesh sizes and the short-term effect of physical disturbance by the boliche. Monitoring suggested potential trophic effects of this fishing gear: the catch of large, long-lived, carnivorous species declined after the introduction of the boliche in the CGSM, whereas catch rates of smaller, shorter-lived, and lower trophic level species increased. Surveys revealed that the boliche retained 41 species. The by-catch made up 62% of the total catch and the remaining 38% involved the three target species Eugerres plumieri, Mugil incilis and Cathorops spixii. Selectivity experiments showed that 2.5 in. stretched mesh size gill nets caught more species than the 3.0-in. mesh. The smaller mesh also increased the risk of a critical reduction in the spawning stock of target species (notably E. plumieri); a situation that could affect the fish community if mesh sizes lower than 2.5 in. were intensively used. Suspended particulate matter significantly increased after fishing activity, with higher resuspension on mud-shells and mud substrata, whereas dissolved oxygen showed no appreciable changes after fishing operations. Notwithstanding, the activity of the boliche would generate sediment resuspension between 382 and 470 t day⁻¹, which could lead to potential cascade impacts on water quality. We propose a framework of redundancy in management measures in order to simultaneously reach management and conservation goals.     

两种结构延绳钓渔具使用效果的比较研究--以金枪鱼(Thunnus)为例

分析比较两种不同结构的延绳钓渔具 1998年 2～ 9月期间在印度洋东部作业的生产效果。结果显示 ,钓具 A(平均放钓水深 90 .8m)与钓具 B(平均放钓水深 72 .7m)相比 ,钓捕效果差异显著 ,在渔获尾数、渔获重量、上钓率三个指标上 ,A钓具分别高于后者 2 9.52 %、30 .2 1%和9.80 %。提出了符合印度洋生产需要的钓具优化设计方案。     

Connections or conflict? A social and economic analysis of the interconnections between the professional fishing industry,recreational fishing and marine tourism in coastal communities in NSW,Australia

Resource conflict is a common feature of coastal management. This conflict is often managed by using spatial planning tools to segregate uses, with access decisions made through a comparison of the economic costs and benefits of the competing sectors. These comparisons rarely include an in-depth analysis of the extent or nature of the conflict. One commonly experienced form of resource conflict in coastal communities involves professional fishing, recreational fishing and broader coastal tourism. In New South Wales, Australia the professional fishing industry is often seen as being in conflict with recreational fishing and tourism, and there are frequent calls to close areas to professional fishing, arguing that this will provide improved economic benefits to local communities. This research examined the relationships between the three sectors using economic valuations, qualitative interviews and a large-scale representative questionnaire of the general public. The results revealed highly interconnected and mutually supportive relationships, with professional fishing providing a range of services that benefit both tourism and recreational fishing. These results suggest that spatial management exercises that seek to segregate or remove one sector from an area, may be counterproductive to the interests of all these groups. Relying on economic valuations of each sector as if they stand alone is insufficient to adequately understand their roles in local communities. Resource allocation decisions should be based on evaluations that consider the interconnections between sectors, and consider whether negotiated sharing of resources may provide greater community benefits than excluding certain groups of users.     

The bottom line: An investigation of the economic,cultural and social costs of high seas industrial longline fishing in the Pacific and the benefits of conservation

High sea industrial longline fishing can be understood as a case study of the cultural, economic, environmental and social impacts of unsustainable fishing technology. While much attention has been attributed to the impact of industrial longlines on the marine ecosystem, little is known about the impact of longline fishing on local food security, employment, cultural belief systems and traditions, revenue generation from marine tourism and climate change. New data demonstrate that the contributions of Marine Protected Areas, marine tourism and recreational fishing to local coastal economies dwarf the contributions of longline fishing. When combined with the impact of overfishing on coastal fishing communities and fish consumers, policies promoting sustainable fisheries must be expanded to take these other factors into account along with issues of biodiversity.     

The bottom line: An investigation of the economic, cultural and social costs of industrial longline fishing in the Pacific and the benefits of sustainable use marine protected areas

Industrial longline fishing can be understood as a case study of the cultural, economic, environmental and social impacts of unsustainable fishing technology. While much attention has been attributed to the impact of industrial longlines on the marine ecosystem, little is known about the impact of longline fishing on local food security, employment, cultural belief systems and traditions, revenue generation from marine tourism and climate change. New data demonstrate that the contributions of Marine Protected Areas, marine tourism and recreational fishing to local coastal economies dwarf the contributions of longline fishing. When combined with the impact of overfishing on coastal fishing communities and fish consumers, policies promoting sustainable fisheries must be expanded to take these other factors into account along with issues of biodiversity.     

Designing ITQ programs for commercial recreational fishing

This paper discusses the potential for implementing individual transferable quota (ITQ) schemes in commercial recreational fisheries, focusing particularly on charter and headboat fisheries. After a brief discussion of ITQs in commercial fisheries, the paper discusses the manner in which rents get dissipated in commercial recreational fisheries. Fishing mortality in recreational fisheries is determined as a joint outcome of angler behavior and trip supply. In the recreational sector under open access conditions, there are likely to be too many vessels providing too many trips at prices that are too low. Vessel input configurations are likely to be distorted in a manner that generates excessive fishing mortality. Designing ITQs for recreational fisheries requires consideration of issues not prominent in the design of commercial fisheries. Among the most important is the manner in which angler preferences and types affect overall mortality from both landings and discards. While catch and release fisheries and pure food fish recreational fisheries are relatively easy to manage with recreational ITQs, fisheries with both angler types present difficult monitoring problems that add complexities to ITQ design. Various ways to design programs that account for both landings and discard mortalities and that generate incentives for anglers and vessel owners to reduce discard mortality are discussed.