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81.
This paper presents an analysis of the effectiveness of the community structural policy in the fisheries sector by comparing the relative level of compliance with objectives (reduction of fleets and economic viability) with the mechanisms that have been implemented (structural funds and allocation of quotas). On the one hand, this analysis shows that there is a positive correlation between the level of structural funds and the attainment of goals. On the other hand, it was found that the greater the relative availability of quotas, the poorer the countries performed in complying with the objective of reducing the fishing capacity, and the higher the expectations of achieving acceptable yields. These correlations, however, were not very strong.  相似文献   
82.
世界大洋长历时局地风速和有效波高的统计与分析   总被引:1,自引:0,他引:1  
本文基于美国海军测地卫星高度计提供的全球范围长历时局地平均风速和有效波高资料进行统计分析,结果表明,世界大洋长历时局地平均风速和有效波高有明显的相关性,其散布点系统地位于Wilson提出的深水充分成长风浪平均风速和有效波高经验曲线之上;并从能量叠加平衡方程,近似定量估计出大洋中长历时涌浪有效波高与局地平均风速的关系。  相似文献   
83.
Dissolved Fe, Mn and Al concentrations (dFe, dMn and dAl hereafter) in surface waters and the water column of the Northeast Atlantic and the European continental shelf are reported. Following an episode of enhanced Saharan dust inputs over the Northeast Atlantic Ocean prior and during the cruise in March 1998, surface concentrations were enhanced up to 4 nmol L− 1 dFe, 3 nmol L− 1 dMn and 40 nmol L− 1 dAl and returned to 0.6 nmol L− 1 dFe, 0.5 nmol L− 1 dMn and 10 nmol L− 1 dAl towards the end of the cruise three weeks later. A simple steady state model (MADCOW, [Measures, C.I., Brown, E.T., 1996. Estimating dust input to the Atlantic Ocean using surface water aluminium concentrations. In: Guerzoni. S. and Chester. R. (Eds.), The impact of desert dust across the Mediterranean, Kluwer Academic Publishers, The Netherlands, pp. 301–311.]) was used which relies on surface ocean dAl as a proxy for atmospheric deposition of mineral dust. We estimated dust input at 1.8 g m− 2 yr− 1 (range 1.0–2.9 g m− 2 yr− 1) and fluxes of dFe, dMn and dAl were inferred. Mixed layer steady state residence times for dissolved metals were estimated at 1.3 yr for dFe (range 0.3–2.9 yr) and 1.9 yr for dMn (range 1.0–3.8 yr). The dFe residence time may have been overestimated and it is shown that 0.2–0.4 yr is probably more realistic. Using vertical dFe versus Apparent Oxygen Utilization (AOU) relationships as well as a biogeochemical two end member mixing model, regenerative Fe:C ratios were estimated respectively to be 20 ± 6 and 22 ± 5 μmol Fe:mol C. Combining the atmospheric flux of dFe to the upper water column with the latter Fe:C ratio, a ‘new iron’ supported primary productivity of only 15% (range 7%–56%) was deduced. This would imply that 85% (range 44–93%) of primary productivity could be supported by regenerated dFe. The open ocean surface data suggest that the continental shelf is probably not a major source of dissolved metals to the surface of the adjacent open ocean. Continental shelf concentrations of dMn, dFe, and to a lesser extent dAl, were well correlated with salinity and express mixing of a fresher continental end member with Atlantic Ocean water flowing onto the shelf. This means probably that diffusive benthic fluxes did not play a major role at the time of the cruise.  相似文献   
84.
South Korea's seven governmental ministries and agency jointly announced a “Master Plan for Arctic Policy” on December 10, 2013. This represents the state's first comprehensive Arctic policy document. This paper aims to analyze the Korean government's Master Plan from both the legal and policy perspectives, as well as to make constructive comments for its improvement. Environmental changes, the need for scientific research, growing economic optimism about the Arctic region, and political leadership have led South Korea to head north. These four factors form the basis for the Master Plan. This document outlines Korea's vision (to be a reliable and responsible partner in this polar region), three policy goals, four strategies, and thirty-one projects connected to the Arctic region. The formation of the Master Plan has been an opportunity for South Korea to organize and compile all the various Arctic activities independently conducted by governmental ministries and agency. In order to improve South Korea's Arctic policy since the Master Plan, the author recommends that the nation prioritize its projects according to its needs and the feasibility of each project. Prudence is required in the drafting and implementation of Arctic policy to respect Arctic states' sovereignties and sovereign rights over the Arctic areas. Finally, strengthening cooperation with the Arctic states and at Arctic forums is indispensable. In particular, bilateral cooperation is essential for South Korea to perform economic activities such as the exploration for oil and gas.  相似文献   
85.
活动断层、地震灾害与减灾对策问题   总被引:19,自引:4,他引:15  
本文在对活动断层的定义和相关概念的论述基础上,通过活动断层与地震灾害间空间分布上的相关性分析,以及海原断裂带松山和阿尔金断裂带阿克塞老城西等地点的探槽地质剖面的介纠等,揭示出活动断层近地表永久性地质变形的局部化特征,永久变形带宽度一般小于30m。文章最后介绍了美国加州地震断层划定法案的主要内容和活动断层填图计划作为积极有效减灾的一项公益性对策,指出中国大陆地区应有步骤地开展大比例尺活动断层填图来有效地减轻可能遭遇的地震灾害。  相似文献   
86.
中国中央造山系是由亲劳亚的北方陆块群、亲冈瓦纳的南方陆块群及其间大量过渡性微陆块历经复杂拼合而成的复合型造山带,是中国大陆完成主体拼合的构造结合带。中央造山系自西而东包括昆仑造山带、祁连造山带和秦岭- 大别造山带,保存了古生代—早中生代时期华北、华南、柴达木、塔里木、羌塘等众多大小陆块造山过程的丰富信息,是研究东特提斯构造域原、古特提斯洋构造演化的重要窗口。本文综述了中央造山系地质、地球化学和高精度年代学等多学科研究成果,得到以下主要认识:① 550 Ma之前,众多大小陆块孤立散布于原特提斯洋;② 541~485 Ma,原特提斯洋各分支开始俯冲;③ 485~444 Ma,原特提斯洋持续俯冲,导致秦岭二郎坪弧后盆地、昆仑祁漫塔格弧后盆地打开;④ 444~420 Ma,原特提斯北祁连洋、南祁连洋和商丹洋闭合,昆仑祁漫塔格弧后盆地关闭;⑤ 420~300 Ma,昆仑地区古特提斯洋继承原特提斯洋,古特提斯勉略洋逐步扩张;⑥ 300~250 Ma,昆仑洋自阿其克库勒湖- 昆中缝合带向木孜塔格- 布青山- 阿尼玛卿缝合带发生俯冲后撤;⑦ 250~200 Ma,原- 古特提斯昆仑洋、古特提斯勉略洋关闭;⑧ 200 Ma以来,中央造山系转入陆内造山阶段。  相似文献   
87.
对美国2004年GPS新政策的初步看法   总被引:1,自引:0,他引:1  
简要地回顾美国GPS政策发展历程之后,列出了2004年GPS新政策的要点,对这一政策作了初步评论。目的是提请更多的人参与分析,这对制订我国的政策是有益的。  相似文献   
88.
Utilizing the NCEP/NCAR reanalysis monthly datasets,and based on the filter and standard deviation calculation,the interannual variability of sea surface temperature (SST) and 1000 hPa wind field for the tropical Pacific,Indian and Atlantic Oceans is investigated for the past 20 years (1979-1998).The characters of space-time evolution in SST anomalies (SSTA) for each ocean and corresponding wind anomaly field are acquired by using rotated principal component (RPC) and linear regression analysis methods.Using the method of correlation analysis.the characters of three tropical oceans correlated with ENSO are investigated.The contemporary correlation between the SSTA in the Indian Ocean and in the equatorial eastern Pacific is positive,and there is a weak negative correlation between the SSTA in the equatorial east Atlantic Ocean and in the equatorial eastern Pacific.The lead-lag correlation analysis indicates that the SSTA in the equatorial Indian Ocean lags the dominant Pacific ENSO mode by 3 months,and the SSTA in the equatorial Atlantic Ocean leads ENSO mode by 6 months.The ENSO-correlated components in tropical Indian Ocean and tropical Atlantic Ocean display much the same amount of total variance in each ocean,i.e..14% in the Indian Ocean and 12% in the Atlantic Ocean and the maximums are all above 40%.  相似文献   
89.
随着海洋渔业资源的不断衰退,为了保护渔业资源、推动海洋渔业的可持续发展,自20世纪70年代后期,我国出台了许多海洋捕捞相关政策。文章从投入控制制度、产出控制制度和技术控制制度3个角度出发,以捕捞许可制度、捕捞限额管理和伏季休渔制度等政策为重点,通过整理1980—2017年浙江省渔业经济的相关资料,从海洋捕捞渔船数量和功率、海洋捕捞产量、渔业劳动力数量变化3个方面,深入分析浙江省海洋捕捞现状,提出了完善现有的海洋捕捞政策、加强渔业执法管理力量、加强普法宣传、建立渔业资源调查与评估体系、帮助捕捞从业人员转产转业等对策建议,以期为我国海洋捕捞管理部门提供决策参考。  相似文献   
90.
2013年我国首次向全世界提出人类命运共同体理念,在全球范围内积极倡导人类命运共同体的构建。东北亚共同体是人类命运共同体的组成部分,是中国打造周边命运共同体的重要助力,同时为辽宁海洋经济的发展带来了机遇和挑战。文章通过分析辽宁海洋经济发展现状,梳理辽宁海洋经济发展的相关法律和政策,发现辽宁海洋经济要实现高质量发展还存在海洋经济供给侧结构性改革、海洋环境综合治理、海洋经济协同发展合作等方面的法律和政策缺失,应当加强海洋经济供给侧结构性改革的立法和政策保障,加快海洋经济协同发展合作和海洋环境综合治理的区域性法律与政策的制定,促进东北亚海洋经济协同发展,共同打造东北亚命运共同体。  相似文献   
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