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111.
The 1995 United Nations Fish Stocks Agreement facilitates the creation of regional fishery management organizations (RFMOs) to govern harvests of straddling and highly migratory fish stocks. The stability and success of these organizations will depend, in part, on how effectively they can maintain member nations’ incentives to cooperate despite the uncertainties and shifting opportunities that may result from climate-driven changes in the productivity, migratory behavior, or catchability of the fish stocks governed by the RFMO. Such climatic impacts may intensify incentives for opportunism, and create other management challenges for the RFMOs now governing tropical tuna fisheries in the Pacific and Indian Oceans. 相似文献
112.
东海北部海域虾类不同生态类群分布及其渔业 总被引:5,自引:0,他引:5
本文根据1986~1991年对东海北部海域(26°00’~326°00’N,100m水深以浅)虾是调查资料,研究了不同虾类的栖息水深与调查区水系分布之间的关系,把本海区的虾类资源划分为广温低盐,广温广盐和高温高盐三个生态类群,并阐明各生态类群及主要种类的分布特点。文中还叙述了东海区拖虾渔业的发展现状,讨论了今后的发展对策。 相似文献
113.
《Marine Policy》2015
This paper explores the failures of the quota allocation system in the hake fishery in Walvis Bay, Namibia through an examination of the complex processes that link commodities, labour, production, markets, and knowledge in the industrial setting. The relationships between state regulations and public nature point to a specific engagement in which nature is divided, distributed, and owned, namely through the market driven prospects of transferable quotas. This article examines fishing quota as a set of relations that links the transformation of fish from biological organism to global product and thus weaves science, the state, markets, and social relationships into an entanglement of different forms of capital. In this context, the tension between the quota holder, the value of that quota, and their participation in the industry reflects a complex network of capital mediated through various strategies. Based on ethnographic research in the Namibian trawl sector, this article surfaces these modes of capital in the dynamics of the fishing operations. As such, the fishing industry, the company that holds the fishing rights, the government׳s role in quota allocations, the vessels, gear, and technologies, and the relationships and roles of the crewmembers and skippers׳ knowledge all contribute to a particular formulation of fishing practices. Fisher׳s knowledge in industrial fishing practices becomes a site in which to explore the consequences of ITQs that may also begin to destabilise the neoliberal business model for fisheries in times of crisis. 相似文献
114.
Magdy T. Khalil 《International Journal of Salt Lake Research》1996,5(3):241-251
Growth rates of the main mullet species (Liza ramada andMugil cephalus) in Lake Manzala are low compared to those in other Egyptian lakes. But average growth rates during the period 1989–1993 were relatively faster than in the 1960's. Spawning and migration seasons have been determined for every species, and their distribution in the lake, in terms of certain ecological parameters (salinity, turbidity and dissolved oxygen) have been investigated. Changes in the mullet fishery in the lake during the past 70 years have been studied. Due to an increase in nutrient loading and a decrease in salinity, mullet declined from 65 per cent of the total catch during the 1920's to only 2.2 per cent during the early 1980's. As a result of fisheries management and development programmes from 1989 to 1993, mullet production increased to 9.2 per cent of the total catch. 相似文献
115.
《Singapore journal of tropical geography》2002,23(2):236-243
Books reviewed:
Maruja M.B. Asis, (ed.) The Philippines as Home: Settlers and Sojourners in the Country.
Hans Gooszen, A Demographic History of the Indonesian Archipelago, 1880–1942.
Karin Bras, Image-Building and Guiding on Lombok: The Social Construction of a Tourist Destination.
K.S. Chon, (ed.) Tourism in Southeast Asia: A New Direction. 相似文献
Maruja M.B. Asis, (ed.) The Philippines as Home: Settlers and Sojourners in the Country.
Hans Gooszen, A Demographic History of the Indonesian Archipelago, 1880–1942.
Karin Bras, Image-Building and Guiding on Lombok: The Social Construction of a Tourist Destination.
K.S. Chon, (ed.) Tourism in Southeast Asia: A New Direction. 相似文献
116.
回顾了南极海洋生物资源养护委员会(CCAMLR)管理体系中科学观察覆盖的主要要素,以及在过去的6年中中国南极磷虾渔业执行科学观察计划的主要成果,旨在帮助中国磷虾渔船更好地理解和执行相关的政策、规定。国际科学观察制度是CCAMLR管理体系中最为重要的监管组成部分。它是由观察员指派、职责和方法标准、执行效果评估等组成的相对独立管理机制。科学观察员覆盖率是其实施策略的核心评价指标,它在渔船、网次以及具体观察任务3个层次都有不同的管理规定。南极磷虾渔业必须接受CCAMLR严格监管并实施科学观察。2009—2015年6个渔季,中国渔船在贯穿所有渔业活动中,按照CCAMLR要求执行最大可能全面、系统的观察覆盖。已有的23船次中,19船次执行科学观察,聘用科学观察员近30人。各渔季的观察天数覆盖率介于81%—100%(平均覆盖率为94%);渔船覆盖率介于66%—100%,6个渔季平均覆盖率为82%,超过CCAMLR的50%的要求。为应对南极磷虾渔业科学观察管理可能的调整,建议我国建立开放的科学观察培训机制,积极储备极地渔业国家科学观察员人力资源,开拓灵活简便的多重委派途径。 相似文献
117.
青岛近海春、秋季渔业资源群落结构特征的初步研究 总被引:11,自引:1,他引:10
根据2004年5月和10月在青岛近海进行的渔业资源底拖网调查,对该海域渔业资源群落结构特征进行了初步研究.结果表明,春、秋季2个航次在该海域共捕获渔业资源种类76种.春、秋季单位网次渔获量分别为12.9kg/h和6.1kg/h,优势种类主要为赤鼻棱NB023(Thrissa kammalensis)、大泷六线鱼(Hexagrammos otakii)以及口虾蛄(Oratosquilla oratoria)、日本枪乌贼(Loligo japonica)等无脊椎动物.分别计算了青岛近海春、秋季渔业生物群落的种类丰度指数(R)、多样性指数(H′)和均匀度(J′).聚类分析、单因子相似性分析(ANOSIM)以及相似性百分比分析(SIMPER)表明该水域渔业资源群落结构存在一定程度的时空异质性.青岛近海渔业资源呈现出明显的小型化和低质化特征. 相似文献
118.
119.
太平湖水库的底栖动物 总被引:8,自引:3,他引:5
研究了太平湖水库底栖动物群落组成(1992-1993年)定量样品出现26种(属),主要是寡毛类和摇蚊科幼虫,软体动物只有1种,现存量有明显的季节差异,本次调查结果与1985-1986年资料比较,种类数减少,现存量显著增加,生物量由0.562g/m^2增加到3.90g/m^3生物多样性指数偏低,底栖动物的参数与环境因素进行了相关分析,寡毛类的密度和生物量与总氮,总磷正相关,水生昆虫的密度和生理量与水 相似文献
120.