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1.
U. Tietze 《Marine Policy》1984,8(4):330-336
This article considers the development of small-scale fisheries in southern Asia. It outlines a training and visit system that has been widely used in agricultural extension work, and suggests how such a system could be applied to fisheries. Extension workers not only give technical advice, but they attempt to change sociocultural attitudes that impede development. The author describes how a fisheries extension service should be organized. 相似文献
2.
《Marine Policy》2017
The purpose of this paper is to analyse the relationship of the proposed new UNCLOS Implementing Agreement concerning the conservation and sustainable use of marine biological diversity of areas beyond national jurisdiction with the current legal framework concerning fisheries. It elaborates on selected elements that are under negotiations, namely: marine genetic resources, area-based management tools, including marine protected areas, as well as environmental impact assessments. Each of those elements is analyzed with particular emphasis being laid on the following issues. Firstly, how the current legal status quo in the relevant area looks like. Secondly, how the question of fisheries could be included in a future treaty and, thirdly, what bearing it could have on the current framework of the management of fisheries.The article concludes with the identification of possible fields where the new treaty could bring added value. However, some possible challenges are mentioned as well. They relate in particular to the fact that the mandate of negotiations underscores that they shall not ‘undermine existing legal instruments and frameworks and relevant global, regional and sectoral bodies’. 相似文献
3.
《Coastal Engineering》2005,52(10-11):931-947
This paper deals with wave overtopping associated to low emergent detached breakwaters. It starts presenting the various mechanisms which define the functional behaviour of detached breakwaters which are frequently overtopped. The emphasis is on the role played by overtopping and how this contributes to the wave pumping in the area around the structure. The paper then reviews the available formulations for predicting overtopping, considering the sensitivity of various equations to climatic drivers and their suitability for low crested coastal structures. The paper then analyzes nearshore circulation models and how overtopping discharges can be included. This is illustrated with a sample Q-3D model by analyzing the differences obtained with/without overtopping. The emphasis is on the implications for the functional design of the structure and its morpho-hydrodynamic impact. The main conclusion is the sensitivity of the functional design of such structures to the underlying hydrodynamics processes and the importance to explicitly include overtopping for numerical simulations of the morpho-hydrodynamic behaviour of low crested breakwaters. 相似文献
4.
《Oceanic Engineering, IEEE Journal of》1978,3(4):117-119
Ocean measurement systems for the 1980's will require improved capabilities to sample and measure specific ocean parameters. With the increasing costs of ocean operations, these systems must be designed and produced to yield a higher degree of performance and reliability than has been previously available. Also, new capabilities will be required as program emphasis shifts to the continental shelves and margins where the understanding of coastal processes, energy development and production, ocean waste disposal, and improved water quality are of increasing social and economic importance. Some of the requirements for improved marine measurement systems and how they can be achieved are discussed below. 相似文献
5.
《Deep Sea Research Part II: Topical Studies in Oceanography》1999,46(6-7):1335-1355
A three-dimensional hydrodynamic ocean model coupled to a thermohydrodynamic model for young sea ice is applied to study shallow haline convection in the central Greenland Sea, with an emphasis on sub-mesoscale ice–ocean interactions. Two types of young sea ice are distinguished; i.e., frazil and pancake ice, both acting different on surface heat, salt, and momentum fluxes. Two scenarios are considered: (a) continued frazil-ice production during steady winds, and (b) the same scenario but with the intermittent formation of pancake ice during a short intervening period of low winds. Brine release due to new-ice production creates shallow convection in both cases. Under conditions of continued frazil-ice production, ice streaks develop at the sea surface, finally becoming oriented roughly parallel to the wind. These streaks are the result of convective plumes that induce organized patterns of convergent and divergent surface currents. Frazil-ice is herded into convergence zones where it becomes as thick as 6 m within 24 h. The studies suggest a strong relationship between streak spacing and the penetration depth of convection, given by an aspect ratio in the range of 2–3. After pancake ice has been formed, however, the organized ice streaks vanish, developing into complex patterns of pancake ice. This finding is in agreement with recent field observations in the Greenland Sea Is-Odden ice tongue. With the existence of pancake ice, moreover, the surface-averaged buoyancy flux decreases and is determined from the integral of local sub-mesoscale ice–ocean interactions. 相似文献
6.
John W. Harbaugh 《Marine and Petroleum Geology》1984,1(4):298-312
Estimation of prospect outcome probabilities in numerical form should be a central objective for petroleum geologists. Most numerical estimates of outcome probabilities represent subjective guesses. While the effectiveness of subjective procedures is difficult to gauge, several postmortem analyses suggest that subjective procedures are ineffective. Objective procedures for estimating outcome probabilities should yield much improved estimates. Objective procedures require that geological, geophysical and production data be organized so that geological and geophysical characteristics of prospects interpreted before they were drilled can be compared systematically with outcomes of prospects after they have been drilled. An example application that involves well data and an example application that involves seismic data demonstrate that objective procedures are simple in principle, but require organization of information in a form suitable for computation of frequencies, on which objective estimates of probabilities can be based. 相似文献
7.
The 10th International Conference on Gas in Marine Sediments (GIMS10) took place from 6 to 11 September 2010 in Listvyanka (Russia), on the shores of Lake Baikal. The conference was organized as a double jubilee, celebrating both the fact that it was the 10th event in this series and the 20th anniversary of the series. A total of 72 oral and 47 poster presentations were given in eight thematic sessions and the presentations were discussed by 126 participants from academic, governmental and commercial institutions from 19 countries, consisting of geologists, biologists, microbiologists, geophysicists, geochemists, oceanographers and limnologists. Volume 32(5/6) of Geo-Marine Letters is a double issue containing 16 selected papers from GIMS10, and has been guest edited by M. De Batist and O. Khlystov. The papers reflect the broad-spectrum disciplines represented at the conference and cover a wide range of aspects of gas in marine sediments from many parts of the world, but with a special emphasis on the gas seeps, gas hydrates and mud volcanoes of Lake Baikal. 相似文献
8.
David Mouillot Olivier Dumay Jean Antoine Tomasini 《Estuarine, Coastal and Shelf Science》2007,71(3-4):443-456
The fundamental idea behind the study of biodiversity patterns is the presumed connection between the shape of species assemblages and the functional ways in which they are organized, this functional organization referring to how species are related to one another, as competitors or members of a web of interactions and to how species are facing similar environmental constraints. Amongst the different facets of biodiversity, functional diversity is certainly a key for ecosystem processes in coastal areas. However, surprisingly, patterns of functional diversity have received little attention until now. After presenting a common framework linking functional diversity patterns to species coexistence theories, the aim of our study was twofold: (1) to seek assembly rules in brackish lagoon fish communities drove by functional traits. To this aim we used null models to examine the influence of two opposing forces acting on community structure: interspecific competition that might prevent the coexistence of the most similar species, and environmental filters that might result in the most similar species to coexist. (2) To seek relationships between fish functional diversity and environmental gradients, if any. Fish sampling was carried out in two coastal lagoons where stations differ considerably in terms of physicochemical parameters. Using morphological functional traits, functional diversity of fish communities was estimated using two recently published indices as well as a new proposed index. Firstly our study was not able to demonstrate a limitation of similarity in coexisting lagoon fishes due to interspecific competition. Conversely our results support the niche filtering hypothesis preventing species too dissimilar from one another to co-occur at the same station. Secondly, salinity was positively related to the functional diversity of fishes in both lagoons suggesting that within species assemblages near the channel species are less redundant than at stations far from the channel where species tend to be functionally similar (benthic and eating zooplankton). 相似文献
9.
The cod resources in the Barents Sea constitute the most important fisheries in Norway. In order to reduce resource allocation conflicts among different gear and vessel groups and to ensure profit for all participants throughout the value chain, the sector is thoroughly organized. The institutions established to ensure long-term sustainability, have been developed within the framework of a joint Norwegian–Russian fisheries management regime. However, due to a very high fishing mortality, the cod stock is now under severe pressure. In addition, a major part of the cod fisheries is highly seasonal and unable to be a stable supplier to neither the land-based industry nor demanding international markets. In parallel, cod farming is expected to become a new emerging industry, with potential to copy the success of farmed Atlantic salmon. Many actors within the cod fisheries fear the future competition from the growing cod farming sector. With reference to important attributes that characterize the cod fisheries and cod farming, this paper discusses how a future farming industry may affect the traditional cod fisheries. Moreover, we discuss how the fisheries may be forced to organize in the future to encounter the expected competition from cod farming. 相似文献
10.
报表服务是大地测量信息系统的一项基本功能，但往往会因为格式的微小调整而导致系统的整体重构。首先分析了当前报表生成方法的缺点，提出了基于XML相关技术生成报表的新思路；然后介绍了以XML为基本语法的统一数据交换接口，屏蔽了各种报表数据源的差异；重点讨论了如何运用XSL技术将接口文件变换成通用的HTML，并对报表中的图形信息用SVG进行描述，从而将报表转换成通用浏览器可以识别的信息模型；最后对此技术进行了实践。通过在系统外部更改报表样式文件，能够实现报表服务的个性化，增强系统的扩展性。 相似文献
11.
The foundation soils for most of the North Sea gravity platforms installed so far have been very stiff over-consolidated clays and dense sand. Two actual platform sites are described that are representative of these soil conditions. It is shown how the design soil parameters required for a geotechnical analysis of the platform foundation have been selected for these two sites. The results of in situ testing, laboratory tests and experience from existing platforms are used, with the main emphasis placed on procedures used at the Norwegian Geotechnical Institute. 相似文献
12.
《Oceanic Engineering, IEEE Journal of》2007,32(4):983-984
Lists, in alphabetical order, the reviewers who contributed to the IEEE Journal of Oceanic Engineering during 2007. 相似文献
13.
蛋白质感染因子与水产养殖 总被引：2，自引：0，他引：2
介绍了蛋白质感染因子的概念、蛋白质感染因子复制机理假说及其证明、蛋白质感染因子多样性等内容，并讨论了水产养殖动物中存在蛋白质感染因子疾病的可能性。 相似文献
14.
Most nonlinear high-resolution bearing estimators are unstable in the presence of correlated noise, system phase errors, and multipath arrivals because they inadvertently place too much emphasis on unstable eigenvectors of the cross-sensor correlation matrix. For moderately correlated noise there will be sufficiently many stable eigenvectors to resolve and localize discrete sources. A method is given (the "stable nonlinear method" or SNLM) whereby reweighting of the eigenvectors is achieved implicitly, without actual calculation of the eigenvectors. This SNLM is compared with Capon's maximum likelihood method (MLM) in simulations of correlated noise, partially correlated signals, and phase errors, and is shown to provide good stability in the cases considered. 相似文献
15.
Gabriele Procaccini Sven Beer Mats Björk Jeanine Olsen Silvia Mazzuca Rui Santos 《Marine Ecology》2012,33(4):522-527
In March 2011, the Ecophysiology and Genetics Working Groups of the European Science Foundation COST Action ES 0906, entitled Seagrass Productivity: From Genes to Ecosystem Management, organized an exploratory workshop entitled “Linking Ecophysiology and Ecogenomics in Seagrass Systems”. The goal of the workshop was to discuss how to integrate comparative gene expression studies with physiological processes such as photosynthetic performance, carbon and nitrogen utilization and environmental adaptation. The main questions discussed for integrative research related to mechanisms of carbon utilization, light requirements, temperature effects and natural variation in pH and ocean acidification. It was concluded that the seagrass research community is still in the nascent stages of linking ecophysiology with genomic responses, as carbon and nitrogen metabolism of seagrasses have not been sufficiently well studied. Likewise, genomic approaches have only been able to assign meaningful interpretations to a handful of differentially expressed genes. Nevertheless, the way forward has been established. 相似文献
16.
《Marine Policy》2015
This paper describes how and why a relatively minor, mostly native non-market economy founded on subsistence-caught Chinook salmon in Alaska has become the object of controversy and increasing regulatory pressure. Small-scale exchanges of cash for subsistence-caught fish conflict with a neoliberal emphasis on markets, profit maximization, and private property. This paper clarifies the role of neoliberal policies in shaping and even causing the controversy over these exchanges, and the consequences for management of Chinook salmon on the Yukon River. 相似文献
17.
This special issue of Geo-Marine Letters presents selected contributions from the international conference Particles in Europe
(PiE) 2010 organized by Sequoia Scientific, Inc., and the Laboratoire d’Océanographie de Villefranche (LOV) on 15–17 November
2010 in Villefranche-sur-Mer, France, and guest-edited by Ole Mikkelsen, Malik Chami and David Doxaran. PiE was initiated
in 2008, in order to promote and further our understanding of the importance of suspended particulate matter (SPM) for a very
wide range of processes in the aquatic environment—from optics and acoustics, over sediment transport, to the global carbon
balance. The papers in this special issue are in particular concerned with the interaction between SPM and water optical properties,
as well as how to use optical proxy measurements to understand SPM processes. The next PiE conference is scheduled for 17–19
October 2012 in Barcelona, Spain. 相似文献
18.
《Marine Policy》2014
China is the world's largest country in terms of fish production, yet its fisheries management is comparatively unknown outside the country. This article gives an overview of the current management system and highlights some of its challenges. In the past 30 years, the Department of Fishery Administration has formulated and organized a series of conservation and management regimes and measures. The most important tools are minimum mesh size regulation and a range of input control measures, including seasonal closures and attempts to control fishing capacity through licensing and limiting total engine power. However, fisheries output is only controlled through a nation-wide total catch limit. Certain progress has been achieved, but there are still problems as the resource situation is poor. While the existing measures could, in principle, improve sustainability, their enforcement is insufficient, and they do not limit fishing effort in a way that would allow recovery. 相似文献
19.
Yachts and recreational boats have been growing in popularity throughout the world. In the United States alone they have a 2% annual growth rate. This growth has created the market for new boats built with improved hull materials and new hull forms, propulsion motors and fabrication techniques. With this growth in boat designs and technology developments, it is useful to examine the current trends in pleasure boat design. This paper addresses the development and utilization of a relational pleasure boat database BOATDSS–Boat Decision Support System. The BOATDSS database contains the data on 850 boat designs. The Decision Support System portion of the BOATDSS is organized to use this data for decision support such as a buyer shopping or a builder examining the potential of a new boat entering the present boat market. Several results from BOATDSS are presented to illustrate its use during the conception and preliminary design of recreational boats. 相似文献