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1.
This paper analyses, using a qualitative methodology, some of the possible causes of the recognised failure of fisheries policy concerning traditional fisheries. Through a case study in a Spanish Mediterranean port (Gandia), it concludes that the basic problem is the lack of legitimacy of political institutions for fishermen. Any attempt to implement an effective fisheries management must recover this legitimacy, by harnessing existing social capital of these communities through the adoption of new models of fisheries co-management and the revaluation of local knowledge.  相似文献   

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An analysis of the structural and functional characteristics of zooplankton community and their coupling with the synoptic situation was carried out for the spring period in the northern Sea of Okhotsk. The years of 2000 and 2001 may be referred to as “cold” type due to the significant extent of the ice-covered area. Based on the ice cover extent, the years of 2004 and 2005 may be referred to as “warm” years due to the decreased extent of the ice-covered area. The “cold” and “warm” years did not significantly differ from each other in terms of the total zooplankton biomass. In the northeast Sea of Okhotsk, the zooplankton abundance increased during the “cold” years, while, in its northwestern part, the zooplankton abundance increased during the “warm” years. The different types of years significantly differ in the species structure of the macrozooplankton community. The abundance of copepods was higher in the “warm” years, whereas the chaetognath abundance increased in the “cold” ones. These features of the dynamics and distribution of zooplankton in the northern part of the Sea of Okhotsk also affected its productivity. The higher production of the elements of the zooplankton community that was revealed in the “warm” years was caused by the increase in the seasonal P/B ratio of both nonpredatory and predatory species. In the “warm” years, the production of nonpredatory zooplankton was higher in the northwest, while, in the “cold” years, it was higher in the northeast of the area.  相似文献   

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The current study analyzes the competitiveness of marine economies in provinces/districts along the eastern coast of China. The current work reviewed the development of marine economy in China over the past decade, and analyzed strategies of each regional economy regarding natural resource endowment and policy priorities in five major coastal provinces of China. Through comparative study of local marine policies and industrial priorities, it is found that the Chinese marine economy is largely oriented towards heavy industry. Local governments focus on land reclamation and often neglect environment protection, which resulted in similar dysfunctional structures of regional industrial policies in these provinces. Based on these findings several policy suggestions are proposed.  相似文献   

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《Marine Policy》2002,26(1):1-11
This article examines the evolution of foreign ownership in the UK fishing fleet in the context of policy developments at European and national levels. We argue that the characterisation of all foreign ownership as “quota-hopping” is misleading because it oversimplifies the means by which foreign access to fish quotas has been obtained. The paper considers the incentives for foreign ownership and the likely economic impact on the UK. It is concluded that the net impact may be rather small, but that the issue nevertheless raises questions for the allocation of fishing rights under the European Community's Common Fisheries Policy.  相似文献   

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The northern Gulf of Mexico and its diverse natural resources are threatened by population and development pressure, and by the impacts of rising sea level and severe storms. In the wake of the devastating 2005 hurricane season, and in response to the complex management issues facing the region, the U.S. Geological Survey organized the multidisciplinary “Northern Gulf of Mexico Ecosystem Change and Hazards Susceptibility” project. This special issue of Geo-Marine Letters hosts a few of the early results in the form of 11 papers covering three themes: (1) the control exerted by the underlying geologic framework on geomorphology and nearshore processes and features; (2) impact of human activities on nearshore water quality; and (3) hurricanes and associated effects.  相似文献   

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The variability in global oceanic evaporation data sets was examined for the period 1988-2000. These data sets are satellite estimates based on bulk aerodynamic formulations and include the NASA/Goddard Space Flight Center Satellite-based Surface Turbulent Flux version 2 ( GSSTF2), the Japanese-ocean flux using remote sensing observations (J-OFURO), and the Hamburg Ocean-Atmosphere Parameters and Fluxes from Satellite version 2 (HOAPS2). The National Center for Environmental Prediction (NCEP) reanalysis is also included for comparison. An increase in global average surface latent heat flux (SLHF) can be observed in all the data sets. Empirical mode decomposition (EMD) shows long-term increases that started around 1990 for all remote sensing data sets. The effect of Mt. Pinatubo eruption in 1991 is clearly evident in HOAPS2 but is independent of the longterm increase. Linear regression analyses show increases of 9.4%, 13.0%, 7. 3%, and 3.9% for GSSTF2, J-OFURO, HOAPS2 and NCEP, for the periods of the data sets. Empirical orthogonal function (EOF) analyses show that the pattern of the first EOF of all data sets is consistent with a decadal variation associated with the enhancement of the tropical Hadley circulation, which is supported by other satellite observations. The second EOF of all four data sets is an ENSO mode, and the correlations between their time series and an SO1 are 0.74, 0.71,0.59, and 0.61 for GSSTF2, J-OFURO, HOAPS2, and NCEP in that order. When the Hadley modes are removed from the remote sensing data, the residue global increases are reduced to 2.2% , 7. 3%, and 〈 1% for GSSTF2, J-OFURO and HOAPS, respectively. If the ENSO mode is used as a calibration standard for the data sets, the Hadley mode is at least comparable to, if not larger than, the ENSO mode during our study period.  相似文献   

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《Oceanologica Acta》2002,25(5):219-226
The Mid-Atlantic Ridge is the target of an emerging international ecosystem study under the Census of marine life programme. This pilot project shall gather new knowledge on biodiversity, distribution patterns, and ecological processes, and the overriding aim is “to describe and understand the patterns of distribution, abundance and trophic relationships of the organisms inhabiting the mid-oceanic North Atlantic, and identify and model ecological processes that cause variability in these patterns”. The project will focus on pelagic, benthopelagic and epibenthic macrofauna, and analyse distribution and abundance patterns in relation to the abiotic and biotic environment, as well as trophic relationships and life history strategies. Fish, crustaceans, cephalopods and gelatinous plankton and nekton have the highest priority in the study. A major challenge of the project is to overcome observation difficulties at large depths and in rugged terrain. A central aim is thus to utilise modern remote sensing technology (acoustics, optics) using advanced instrument carriers (e.g. towed vehicles, ROVs, AUVs, etc.). The project will be carried out as a multi-ship operation in 2003–2005, and the ongoing planning is a collaborative effort involving many nations around the North Atlantic. The project will work on the Mid-Atlantic Ridge and in adjacent waters from the Azores to Iceland, both by surveying large areas by acoustics and mid-water trawling, and by focusing on three selected sub-areas for intensive sampling and observation by traditional and novel methods and technology. Overlapping with the field seasons, the period 2004–2008 will be an analytical phase, also including submission of data to OBIS.  相似文献   

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The radionuclide ~(210) Pb is suitable for century-scale dating and has been used to calculate the sedimentation rate in a variety of environments. However, two common ways to apply 210 Pb dating techniques may give misleading results. One is "prolonging of age", i.e., using the calculated sedimentation rate to date back to 200 or 300 years.This practice must be treated with caution because the 210 Pb dating techniques do not guarantee direct dating for ages much older than 100 years. Another is "loss of age", i.e., the calculated time span between the topmost layer and the 210 Pb background layer in cores is less than 100 years when an apparent sedimentation rate is used in the calculation. Here, we propose that based on the principle of 210 Pb dating, the upper limit of age suitable for direct210 Pb dating is between 110 and 155 years. The "prolonging" application is acceptable only if the sedimentary environment in the past several hundred years was stable and the sedimentation rate was generally constant, and verification with independent evidence(such as historical records or biomarker methodology) is needed.Furthermore, after analyzing many published and collected data, we found four possible reasons for the "loss of age". First, the compaction effect of sediment should be corrected in laboratory analysis or else the calculated age will be underestimated. Second, the accuracy and uncertainty of 210 Pb activity measurement affect the judgment of the background. To be cautious, researchers are apt to choose a background activity with a younger age. Third,use of a slightly smaller value of supported 210 Pb activity in a calculation will lead to considerable underestimation of the time span. Finally, later-stage erosion and migration are common for sedimentation, which lead to loss of sedimentary records and are often reflected as a "loss of age" in cores. We believe that proper use of 210 Pb dating data may provide helpful information on our understanding of sediment records and recent environmental changes.  相似文献   

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随着英国海军"伊丽莎白女王"号航母在英国国内各家船厂的陆续组装,该航母将要安装的关键设备也都在紧锣密鼓地进行生产、调试。作为该级航母的"千里眼"——"工匠"(ARTISAN)三坐标雷达已于2010年通过皇家海军关键设计审查,标志  相似文献   

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《海洋世界》2011,(11):8-8
科学家们发现,那些经常“一心多用”的人,往往事倍功半。 美国斯坦福大学的教授埃亚勒·奥斐认为:当人们始终在接受眼前的所有信息时,就难以令头脑中已存储的信息保持独立。研究人员利用层析X线照相法,观察大脑的活动,发现人们在处理多件事情时,是大脑额叶前部皮层在发挥关键的作用。额叶前部皮层能提高人的工作效率,但它只是在迅速调节两件事先后处理的顺序,有时这种转换速度可以快到让我们产生“同时进行”的幻觉。大脑处理两件事的转换需要时间,人们可以通过练习缩短转换时间,却不可能将其缩短到任意小的数值。  相似文献   

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Over 20 occurrences of discontinuous limestone blocks, locally called calcari aLucina, were mapped in the Tuscan—Romagna region of the northern Italian Apennines. The limestones, consisting of a variable mixture of authigenic carbonates (calcite, dolomite, and aragonite), sulfides (primarily pyrite), and allogenic silicates, occur in association with turbidite and hemipelagite units that were deposited in foredeep basins during early to late Miocene times. The limestone blocks are interpreted to represent relicts of carbonate buildups formed around methane-rich fluid vents on the basis of their (1) striking petrographic similarities to carbonates from cold vents in the modern oceans; (2) unique chemosynthetic-like fauna, and (3) anomalously negative 13C values ( 13C = – 16 to – 58 PDB). The contemporaneous tectonism of the Apennine orogeny is likely to be the primary cause for the expulsion of the methane-rich fluids to the seabed in a manner analogous to the fluid-flow processes occurring at modern accretionary prisms.  相似文献   

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1982年5月1日下午4时13分,英国皇家海军核动力攻击型潜艇“征服者”号,首次投入战斗就一举击沉了阿根廷海军唯一的巡洋舰“贝尔格拉诺将军”号,开创了核潜艇参加实战并获胜的先河。“征服者”号是用何种尖端武器克敌制胜的呢?这成为一宗鲜为人知的秘密。一“征服者”号系英国“勇士”级攻击型核潜艇,1967年12月开工建造,1970年11月开始服役。该艇长86.9米,吃水8.2米,水面排水量  相似文献   

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According to the initial vision of "digital earth" (DE), the public should constitute a significant proportion of its users. However, to date, most of the studies and applications have focused on science, the private sector and government. A DE-supported online oceanic educational public service and popularization system, iOcean, is studied. First, the vision for the public’s engagement with "digital ocean" is described: an analysis is presented from four aspects, i.e., the space dimension, the time dimension, the state dimension and its relationship with human beings. Second, the technical framework of iOcean is discussed, including data updating and model computing, the data, the function, and the application layers. Third, two key technologies are studied in detail that will enable the construction of iOcean. More than half a million public viewers have used the current version’s website. Practical demonstrations show that iOcean can bring virtual oceans to web browsers and desktops and construct a bridge between government departments and the general public.  相似文献   

19.
张涛 《海洋世界》2021,(3):94-96
“咖啡提神、醒脑、防疲劳……”这是人们对咖啡功能的共识。“但是,你们不要忘记水手是咖啡的真正传播者!”这是海默船长的口头禅。海默船长是咖啡的忠实“伴侣”和“粉丝”。  相似文献   

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你知道吗,口香糖可以做“鱼饵”而且——  相似文献   

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