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《Marine Policy》2017
Mussel farming is the largest aquaculture activity in Spain both in volume and value, being a key pillar for the development of the coastal areas in Galicia (NW Spain), where this production is concentrated. The available scientific knowledge suggests that in the long term the primary productivity of the Galician estuaries will be reduced due to climate change. Consequently, adaptive management will be required to face this challenge. The impact of the likely production decrease will depend, among other factors, on the availability of substitutes, being their identification the main object of this research. So, it was analysed whether this markets are integrated or not through cointegration tests, finding that only the French and the Spanish markets are partially integrated. This implies that since very little substitutes are available for the Galician fresh mussels, decreases in production will not necessarily affect producer's income, as prices increases will compensate the (eventual) reduction in volume. In terms of policy, this study suggests that market intelligence may contribute to an adaptive, pragmatic and flexible framework to face climate change impacts, avoiding too anticipated or blind responses that may result in economic, environmental and social costs. 相似文献
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我国大陆桥沿线矿产资源丰富,有64种矿产的保有储量在全国名列第一,其中煤,钠盐,石膏,镍,铝土矿,钼,耐火粘土和玻璃硅质原料等主要矿产在全国具有举足轻重的地位,发展潜力大,开发前景好。新亚欧大陆桥的贯通,给我国沿桥地区矿产资源开发和经济发展提供了契机。应把握机遇,尽快将矿产资源优势转化为经济优势,实现经济增长方式由粗放型向集约型转变。根据沿桥矿业现状,市场需求和资源保证程度,应重点发展能源等矿业。 相似文献
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本文简单介绍了工程物探技术的应用领域及主要特点,以简表形式列出了当前工程物探技术的主要方法,分析了当前工程物探技术应用状况及市场前景,着重讨论了工程物探技术进一步开发的思路和观点。 相似文献
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长期以来,由于忽视了人口、土地、粮食与灾害系统内各因素的相互协调,人类的生存与发展基本问题越来越多地摆在我们面前,致使在人口增长过快情况下,产生了土地资源质减量退,粮食生产徘徊不前,自然灾害频繁发生等危害生国计的社会问题,在跨入21世纪的关键时期,如何采取有力措施解决上述问题,已为90年代的重要任务,针对针中国国际本文分析了人口,土地,粮食,灾害相互间的关系,进而提出了相应之对策。 相似文献
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Based on empirical evidence, the article looks at the implications of private sector participation (PSP) for the delivery of water supply and sanitation to the urban and peri-urban poor in developing countries, with particular reference to Africa and Latin America. More precisely, the article addresses the impact produced by multinational companies’ (MNCs) strategies, in light of the pursuit of profitability, on the extension of connections to the pipeline network. It does so by questioning the assumptions that greater private sector efficiency and innovation, together with contract design, will enable the sustainable extension of service coverage to low income dwellers. The strategies of the major water MNCs are considered both in relation to the global expansion of their operations and the adjustment of local strategies to commercial considerations. The latter might result in identifying profitable markets, modifying contractual provisions, attempting to reduce costs and increase income, reducing risks and exiting from non-performing contracts. The evidence reviewed allows for re-assessing the relative roles of the public and private sectors in extending and delivering water services to the poor. First, the most far reaching innovative approaches to extending connections are more likely to come from communities, public authorities and political activity than from MNCs. Secondly, whenever MNCs are liable to exit from non-profitable contracts, the public sector has no other option than to deal with external risks affecting continuity of provision. Finally, market limitations affecting MNCs’ ability to serve marginal populations and access cheap capital do not apply to well-organised, politically led public sector undertakings. 相似文献
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产业集聚、市场结构与生产率——基于中国省份制造业面板数据的实证研究 总被引:4,自引:0,他引:4
利用1987~2003年中国制造业8个产业分省份面板数据对集聚经济效应的存在与否进行了实证研究,研究结果显示在制造业8个产业中,大部分产业存在地方化经济效应和城市化经济效应,即产业自身规模以及其他产业规模对该产业的劳动生产率具有正向影响,从而验证了集聚经济效应的存在性。研究同样对市场结构与生产率之间的关系进行了实证检验,并没有支持"竞争性的市场结构更能促进创新"这一理论预期,在一定程度上说明企业的内部规模经济效应要强于市场竞争对创新的促进作用。 相似文献
48.
金枪鱼渔业作为远洋渔业和海洋经济的重要组成部分,其发展受到各远洋渔业大国的高度重视和大力扶持。文章基于SCP分析范式,从市场结构、市场行为及市场绩效3个范畴研究金枪鱼渔业产业组织的结构特征,分析影响金枪鱼渔业市场结构的因素,探究市场结构、市场行为和市场绩效三者的关系。研究发现:金枪鱼国际生产和贸易垄断集中程度降低,市场竞争的有效性不断加强;金枪鱼的市场结构受到市场集中度、产品差别化,进入和退出壁垒的影响;金枪鱼渔业市场结构、市场行为和市场绩效之间存在相互影响关系。文章最后为我国发展金枪鱼渔业,提升国际竞争力提出了发挥渔业管理组织牵头作用,共同维护金枪鱼市场有效竞争;积极促进企业发展,提高生产研发能力,立足国际市场;创造良好国际环境,切实为金枪鱼渔业发展保驾护航等建议。 相似文献
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The closure of the Hawaiian longline swordfish fishery over the period 2001–2004, which was motivated by the protection of endangered sea turtles, created the elements of a natural experiment that allows identification of the market transfer of catch (and sea turtle bycatch) to other regions. This paper exploits the fact that the vessels in the Hawaiian longline fishery sell their catch in the US fresh swordfish market to analyze the pattern of changes in US fresh and frozen swordfish consumption both before and after the closure regulation was imposed. The mechanisms by which any unintended consequences on endangered sea turtles in other fishery locations in the world are shown to take place through the US swordfish market. At the estimated annual market transfer, a bootstrap analysis of the probability distribution of bycatch rates indicates that the regulation led to an additional 2882 sea turtle interactions at the sample means. 相似文献