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631.
Coastal and residential development along the Atlantic coast of the United States is expected to increase by about 73% between 1980 and 2000. Present estimates indicate that over 59% of the population of the United States lives within 50 miles of the coast. This increase in coastal population coupled with increased demands for fishery products and increased efficiency in catching fish has severely stressed many Atlantic coast fisheries. Fisheries have been affected by increased pollution, habitat loss and overfishing. In 1976, the Magnuson Fishery Conservation and Management Act was passed creating Fishery Management Councils with the goal of imposing strict conservation measures in the U.S. Exclusive Economic Zone (EEZ). This paper discusses potential causes of Atlantic Coast fisheries declines and gives examples of specific fishery plans that have been developed to manage U.S. fisheries. 相似文献
632.
Hydrology and ecology are two important factors affecting the rational utilization of limited water resources within the
arid inland basins of China. They depend on, are influenced by, and interact with each other. But, the functions and significance
of the hydrological ecology vary from upper through intermediate to lower reaches. Abundant rainfall and large runoff in the
upper regions favor the vegetation growth, and the bushy vegetation helps conserve water resources. The large-scale reclamation
in the intermediate regions leads to many sustainable oases, but with severely changed hydrological conditions and destroyed
ecological systems. Human activities result in the degradation of the vegetation and declination of the ecological system
at the intermediate and lower regions. It is necessary to establish study approaches to ecological hydrology in arid inland
river basins.
Received: 30 October 1997 · Accepted: 26 May 1998 相似文献
633.
A framework for risk analysis in fisheries decision-making 总被引:4,自引:3,他引:1
634.
产量模型的比较及在小鳞鱼箴种群的应用(英文) 总被引:1,自引:0,他引:1
产量模型是渔业管理中预测最大持续产量(MSY)的经典方法。MSY仍然是渔业管理的重要目标之一。文章应用模拟数据比较了最常用的产量模型。蒙特卡罗研究表明WaltersandHilborn的动态模型表现最好。这些方法被应用在小鳞鱼箴(HemirhamphussajoriTemminckandSchlegel)种群。Wal-tersandHilborn方法的Bootstrap结果是2250t(吨)的MSY和806艘船的最佳捕捞努力量。与目前2000艘船的努力量水平比较,渔业处于过度捕捞状态,需要大力削减捕捞努力量 相似文献
635.
The high seas fisheries are troubled by overcapacity and lax enforcement of management rules. The idea has emerged that these problems could be dealt with by property rights solutions such as ITQs. Such management tools only emerged after the 200-mile EEZ was established. This made it possible to apply the sovereign state's legislative, enforcement and judiciary apparatus to regulate fisheries. It is argued that without the EEZ such solutions would have been unlikely to emerge, and that a further extension of the EEZ is necessary to apply rights-based regulations to high seas fisheries. The current management regime of high seas fisheries lacks the necessary enforcement apparatus, which makes it necessary to apply trade sanctions, port measures and blacklisting to support regulations of high seas fisheries. It is argued that such measures are likely to be the second best, compared to further extending coastal state jurisdiction. Finally a bioeconomic model is applied to analyze potential gains from cooperation in high seas fisheries. 相似文献
636.
The authors argue that tropical aquaculture could make a significant contribution to the world fish supply, but is hindered by the absence of an adequate research base. They outline the history of aquacultural research, analyse the problem of the lack of a sustained basic research programme for the development of tropical aquaculture, and propose solutions on the basis of successes in agricultural research. 相似文献
637.
Barbara Louise Endemao Walker 《The Professional geographer》2001,53(2):160-177
As processors and marketers of fish, women fishtraders in the Fanti town of Cape Coast, Ghana have become powerful financers and owners of canoes, nets, and other fishing equipment. Since the 1960s, when motors were first introduced to Ghana's artisanal canoe fleet, two interrelated processes have occurred in Cape Coast. First, Ghana's fisheries have become increasingly exploited and—in the case of some species—overfished. Second, the social relations of production in the artisanal sector have shifted from being socially embedded to being more market‐based and impersonal. I argue that two recent Women in Development (WID) projects in particular have contributed to the breakdown of fishtraders’ traditional economic networks and livelihood strategies: (a) loan schemes that target women's associations, and (b) the 1985 Intestate Succession Law, which reconfigured inheritance rights. These WID projects, based on western notions of gender and the household, have created disharmony and mistrust among Cape Coast's fishtraders rather than promoting their “development.” The breakdown of fishtraders’ labor and marketing organizations has resulted in increasingly desperate strategies to get fish, increased degradation of Ghana's marine environment, and uncertainty for the future of the coastal economy. 相似文献
638.
“九七”后香港与内地合作趋向及港资进入内地策略 总被引:1,自引:0,他引:1
本文讨论香港与内地进行经济合作基础与环境,分析了“九七”后两地经济合作的新趋向及港资进入内地将采取的基本策略,并对如何更好地引导港资进入内地提出若干对策和措施。 相似文献
639.
640.