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《Marine Policy》2017
Private enumeration of landings data and traceability is an emerging phenomena in developing world tuna fisheries. The general goal of these systems is to facilitate compliance with mandatory market requirements such as the European Union’s Illegal, Unreported and Unregulated fisheries regulation, as well as support aspirations for voluntary requirements such as the Marine Stewardship Council. The long-term success of these systems appears to be dependent on their ability to complement and extend government data and information systems. Developing and maintaining the credibility of these voluntary private enumeration and traceability systems requires strong market incentives as well as strong state support and assurance. If this credibility can be maintained private fisheries information systems may provide a promising basis for innovative stock assessment and management approaches relevant for complex developing world fisheries such as tuna. 相似文献
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两项新技术及其在海水苗种生产中的应用 总被引：4，自引：0，他引：4
本文介绍了两项新技术，用泡沫净化空气、海水和生物效应灯，及其在海水苗种生产中的应用。文中分别讨论了它们的原理、设计安装及使用效果。希望这两项新技术能够得到推广，以提高出苗率，增加海水苗种生产的经济效益。 相似文献
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珠江口海域环境及其综合治理问题辨析 总被引：5，自引：0，他引：5
分析了珠江口周边陆地与海域所面临的环境复合污染形势及来源，指出海域综合治理应以满足全省乃至全国社会经济可持续发展为前提，通过综合治理，建立新的社会发展秩序、经济发展秩序和使用海环境秩序。提出系统地、定量地研究珠江口海区与外海沿岸流以及与陆地径流的水动力、物质与生物流的相互关系与活动规律，认识海域生态系统的稳定特性与受损害受干扰特征，认识大气系统对海域的作用过程与诱发生态失衡的规律，是建立新秩序的科学基础。 相似文献
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Frederick R. Hess 《Marine Chemistry》1977,5(3):297-302
The use of Radio-Controlled Miniature aircraft by the Woods Hole Oceanographic Institution for obtaining marine air samples is discussed. The particular requirements for gaseous as well as large-volume particulate sampling are discussed and at-sea tests performed from the R/V “Knorr” are described. Handling and logistics of use as well as aircraft characteristics are discussed. 相似文献
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黄河流域在我国经济社会发展和生态安全方面具有十分重要的地位,其下游的黄河三角洲分布有世界上暖温带保存最广阔、最完善、最年轻的滨海湿地生态系统,该区域特殊的地质地貌决定了其生态多样性,需要进行重点研究和保护。文章立足于我国现有湿地保护政策和湿地面积缩小的现状,提出黄河三角洲湿地保护可着重围绕其岸线变化、冲淤速率、地形地貌等开展研究,并采用减压分洪扩充法等治理修复方法扩大湿地面积,为推动黄河流域及黄河三角洲湿地的生态保护和高质量发展提供有效参考。 相似文献
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The data on the species composition, trophic structure, and distribution of macrozoobenthos in Amur Bay obtained in 2001 are presented. Long-term changes in the benthos are analyzed. In 2001, the total benthos biomass significantly increased, although the parameters of the species richness declined as compared to 1986–1989. In 2001, as well as in the 1970s and 1980s, the benthos trophic structure was characterized by the prevalence of deposit feeders. The entire structure of the benthos is evaluated as an eutrophic one. Eutrophication of the bay is considered to be the most probable cause of the negative changes in the benthic communities of the bay in 2001, as well as 15 years ago. 相似文献
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《Coastal Engineering》2006,53(2-3):121-132
This paper presents a review of recent advances in understanding and modelling of hydrodynamic and morphodynamic processes in the coastal zone as well as some challenges for further developments. Different processes are distinguished, and for each of these, essential characteristics of the state-of-the-art are mentioned, with emphasis on recent developments, as well as open questions that are considered important. 相似文献
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评述了2003年10月27-30日在北京召开的“大洋中脊国际学术研讨会”，简要介绍了国际大洋中脊协会(InterRidge)的机构组成、任务和工作进展．以及今后大洋中脊地质研究的发展趋势。这次会议后，中国已成为InterRidge计划的参与成员国(Associate Members)以此为契机，尽快启动中国InterRidge计划，结合中国综合大洋钻探计划(IODP)，以及大洋专项和其他深海调查研究工，有望实现我国在大洋中脊及相关研究领域的跨越式发展，提升我国深海研究领域的整体调查研究水平。 相似文献
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Neogene tectonic activity (Betic Orogeny) along the southern plate boundary of Iberia, as it converged with Africa and the Alboran Plate was inserted between them, propagated along Iberia's west side as far north as Galicia, northwest Spain. As the activity propagated northward, it reactivated structures formed during the Paleozoic (Hercynian), the Early Cretaceous opening of the northern North Atlantic and the Bay of Biscay, and the Paleogene Pyrenean Orogeny when Iberia collided with Eurasia. Recent earthquakes indicate that this tectonism is still active today as far north as northwest Spain. 相似文献
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《Marine Policy》2016
The aim of this study was to empirically assess institutional aspects shaping fishers’ behavior leading to unsustainable resource use, by using the example of destructive drag-net fishing in Zanzibar, Tanzania. A broad institutional approach was used to specifically assess institutional factors influencing the fishers’ reasons for the current use of destructive drag-nets as well as their willingness- and economic capacity to change to less destructive gears. Different regulative, normative, cultural-cognitive and economic factors (tradition, group-belonging, social acceptance, common practice, identity of drag-net users and weak economic capacity) were identified as critical elements influencing the current use of destructive gears, as well as obstructing changes to other gears. Hence, the importance of addressing all of these factors, matching to the different contexts, rather than focusing on fast-moving regulative measures, is emphasized to increase chances of management success. More promising approaches would be resource allocations to more sustainable fishing gears, well-managed gear exchange programs, as well as alterations of slow-moving normative and cultural factors, e.g. awareness raising on the advantages of more sustainable fishing gears, their traditional and cultural values, information on the actual income they generate, as well as education and an exchange of traditional knowledge on how to use them. 相似文献
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The authors describe the effort to provide three-dimensional global thermohaline and sound speed fields for use in the effects of sound in the marine environment (ESME) workbench suite of programs. The primary fields used are from the modular ocean data assimilation system (MODAS), developed by Fox et al. The system provides global thermohaline and sound speed fields on a daily basis using environmental inputs from the U.S. Navy as well as remote sensing of sea surface temperature and sea surface height. To examine the MODAS fields, the authors also used data from the Southern California Bight collected by the California Cooperative Fisheries Investigations as well as high-resolution hydrographic data collected over the continental shelf south of New England as part of the shelfbreak PRIMER experiment. MODAS performs well for features such as large-scale boundary currents and eddies but is more limited in resolving features such as shelfbreak and coastal fronts, which have small spatial and temporal correlation scales. Because of the considerable computational needs of other ESME modules and its use as a planning tool, the authors present a pragmatic approach for future applications. 相似文献
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Li Yucheng Professor Dept. of Civil Engineering Dalian University of Technology Dalian 《中国海洋工程》1992,(2)
Pierson- Moskowitz Spectrum, JONSWAP Spectrum as well as Bretschneider- Mitsuyasu Spectrum are used in this paper for analyzing the influence of wave energy directional spread on refraction of wave spectrum due to both current and topography of sea bed. The author's calculation indicates that such kind influence on the characteristic value of wave height as well as the average direction of wave energy propagation can not be ignored. 相似文献
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深海热液喷口生物群落的研究进展 总被引：11，自引：0，他引：11
深海热液喷口生物群落并不依赖光合作用获取能量,它们是一类独特的生物类型,其食物链的基础是化学合成细菌,这些细菌依靠喷口热液中的还原无机物氧化．利用CO。合成有机碳,它们共生于大个体动物的软组织或绍中,向寄主提供生存必需的有机碳。地质时期古热液喷口生物群落的研究还表明,该类生物群落在古生代（可能更早）即已出现。此外,现代热液喷口与古热液喷口生物群落的比较研究,在探索该生物群落乃至早期生命的起源、演化方面也取得了可喜进展。 相似文献
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Jesper Bartholdy 《Geo-Marine Letters》1985,5(1):67-70
In the salt marsh deposits of the Danish Wadden Sea, a separation has successfully been made of two log-normally distributed
grain size populations, which make up the major part of these fine-grained sediments. The coarse population consists almost
exclusively of silt and is interpreted as material either deposited as resistant flocs or as single particles. The fine population
consists of approximately 50% silt and 50% clay and is interpreted as particles settled as easily destroyable flocs. These
interpretations are confirned by the fact that the relative abundance of the two populations is demonstrated to be related
to the degree of exposure of salt marsh areas. 相似文献