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691.
692.
Randall ReevesCheryl Rosa J.Craig GeorgeGay Sheffield Michael Moore 《Marine Policy》2012,36(2):454-462
The objective of this paper was to investigate and illustrate how insights gained from experience managing human activities in order to protect North Atlantic right whales (Eubalaena glacialis) along the heavily industrialized east coast of North America might be applied in the Arctic, where bowhead whales (Balaena mysticetus) face some of the same risks as right whales. The reduced extent and thickness of sea ice and the resultant longer open-water season have major, complex implications for the Arctic marine ecosystem. Increased maritime ship traffic and commercial fishing in the Arctic are bound to affect bowheads and Native (indigenous) hunting communities who depend on whales for subsistence and cultural identity. Bowheads and right whales were greatly depleted by commercial whaling in the 19th and early 20th centuries. While the Western Arctic bowhead population has been recovering steadily in recent decades, North Atlantic right whales remain highly endangered because of persistent lethal and sublethal vessel strikes and frequent entanglement in commercial fishing gear. Entanglement can be transitory or persistent, with debilitation lasting for months before the animal finally succumbs. Vessel strike and fishing gear trauma has been documented in bowheads, but at a much lower rate than in right whales. Initiatives intended to mitigate the impacts of ship traffic on North Atlantic right whales have included speed limits and routing changes. Those meant to reduce the incidence and severity of entanglements include the modification of gear design and gear deployment practices. Management measures need to be considered in advance in the Arctic in order to minimize the risks to bowhead whales as shipping and industrial fishing expand in the Arctic with ice retreat. 相似文献
693.
The Sea Prince accident was the first VLCC accident in Korea and a shock to the general public and government. Before the accident, any oil-spill management plan, such as National contingency plan (NCP) and regional contingency plans (RCPs), was not available and the resources for oil spills were lacking for the Sea Prince accident. About 5000 tons of oil spilled, polluting large areas of southern coastal waters, damaging the fisheries, including aquaculture. After the Sea Prince accident, Korea's government established various alternatives for dealing with oil spills, such as the NCP, RCPs, Typhoon Refuge Management Plan, and resources for oil-spill response. However, port safety management in emergency situations such as typhoons has not been solved. 相似文献
694.
基于对俄罗斯北萨哈林盆地构造演化及地层充填特征的基础地质特征分析和油气分布规律的总结,对盆地油气分布特征的主控因素进行了探讨。研究认为:盆地的油气分布在平面上具有油气田呈S—N向成带分布,从北向南具有“油减少、气增多”的特点;在纵向上,油气发现的层位具有“北上南下”的特点;在规模上,油气储量分布具有“陆小海大”的特点。油气成藏条件综合评价分析认为,油气分布主要受走滑断裂和三角洲发育的控制,具体表现为:走滑运动与不同时期的三角洲控制着烃源岩的展布,使得油气分布呈北产油南产气的特征;走滑运动和3期三角洲的迁移使得油气发现层位呈“北上南下”的特点;走滑断裂带控制了圈闭规模和保存条件,使得油气田规模呈“陆小海大”的特点。结合以上分析指出,北萨哈林盆地东部海域勘探程度低,含油气系统证实具有多期三角洲和多类型圈闭发育,是北萨哈林盆地具有较大勘探潜力的区域。 相似文献
695.
我国第二代静止气象卫星FY-4A观测能力较之前有明显提升,在天气特别是对流性天气监测和预测中具有较强的应用潜力。利用FY-4A气象卫星多通道扫描辐射成像仪(Advanced Geosynchronous Radiation Imager,AGRI)和闪电成像仪(Lightning Mapping Imager,LMI)数据开展研究,分析了反演产品在强雷暴天气中的应用。研究表明,扫描辐射成像仪多通道组合白天对流风暴红-绿-蓝(red-green-blue,RGB)合成产品可以突出具有强上升气流的对流性雷暴云,较单通道及多通道可见光合成产品具有监测优势;闪电成像仪产品较地面闪电探测闪电产品能够探测到更多的闪电,对新生对流和较弱对流产生的闪电监测具有优势;在华北和黄淮一次强雷暴天气过程中,白天对流风暴RGB合成产品能够监测云系发展的过程,卫星监测闪电活动频数和冰雹活动一致性较好。 相似文献
696.
优质的渔业水域环境是我国渔业可持续发展的重要保障,目前,我国渔业水域环境面临着较为严峻的污染问题,污染事故时有发生,严重影响了渔业的持续稳定发展。为了保护渔业水域环境、防治渔业水域污染事故,我国在《中华人民共和国渔业法》《中华人民共和国水污染防治法》《中华人民共和国海洋环境保护法》等法律中均规定了相关内容,基本形成了渔业水域污染事故的法律规制模式,但仍然存在许多法律问题,如法律规定缺乏实施细则,可行性较低;相关定义模糊不清;事故损害调查方式不够合理等。在此背景下,文章分析了目前渔业水域污染事故对应的民事法律责任、行政法律责任和刑事法律责任,并提出建议,为渔业水域污染事故的处理和归责提供参考。 相似文献
697.
Arrigo A. Cigna 《Ocean Science Journal》2006,41(4):261-290
The concentrations of man made radionuclides in surface seawater since early ′60s are here reported as measured in Italy and
Japan. Most of the data refers to90Sr and137Cs, but occasionally the concentrations of89Sr and134Cs in some Italian samples are also given. The main sources of man made radionuclides were the global fallout produced by
the nuclear weapon tests and the Chernobyl accident. The respective contributions to the contamination of surface seawater
around both countries are discussed. 相似文献
698.
P. Zarka W.M. Farrell M.L. Kaiser E. Blanc W.S. Kurth 《Planetary and Space Science》2004,52(15):1435-1447
Radio signatures of lightning discharges have been detected by the Voyager spacecraft near Saturn and Uranus up to 40 MHz. Corresponding flux densities at the distance of the Earth are up to 1000 Jansky (Jy) for Saturn (1 event per minute above 50 Jy, with 30–300 ms duration) and up to a few tens of Jansky for Uranus. Low Frequency ARray LOFAR will allow us to detect and monitor the lightning activity at these two planets. Imaging will allow us to locate lightning sources on Saturn's disk (even if with moderate accuracy), which could then be correlated to optical imaging of clouds. Such observations could provide new information on electrification processes, atmospheric dynamics, composition, and geographical and seasonal variations, compared to the Earth. In addition, lightning may play a role in the atmospheric chemistry, through the production of non-equilibrium trace organic constituents potentially important for biological processes. LOFAR observations can also help us to assess the existence of lightning at Neptune (marginally detected by Voyager), at Venus (where their existence is very controversial), and at Mars (possibly resulting from dust cloud charging). At Jupiter, low-altitude ionospheric layers of meteoritic origin and/or intrinsically long discharge duration seem to prevent the emission and escape of high-frequency radio waves associated with lightning. LOFAR thus presents good possibilities for the detection and study of solar system planetary lightning; we also discuss its relevance to bring new information on Terrestrial lightning-related upper atmosphere transient phenomena (sprites, TIPPs…). Instrumental constraints are outlined. 相似文献
699.
CHARACTERISTICS OF TECTONIC MIXTITE ZONE IN THE LANCANG RIVER,WESTERN YUNNAN 相似文献
700.
我国西南地区是我国重要的斑岩矿床勘查开发基地,自20世纪60年代以来,相继勘查发现了玉龙、驱龙、普朗、多不杂等特大型斑岩铜矿。初步研究表明,西南地区斑岩矿床的集聚与走滑断裂存在着密切的空间关系。认识并深入研究斑岩矿床与走滑断裂存在着的这种关系,对于斑岩矿床勘查具有重要的意义。在西南地区现有的5个斑岩成矿带开展斑岩矿床勘查时,在沿区域性走滑断裂方向勘查并加强对走滑断层带内或其周围派生的局部引张或挤压地区开展找矿的同时,还应注意开展对鲜水河-小江左旋走滑断裂带及两侧斑岩矿床的勘查。 相似文献