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211.
我国是一个陆海兼备的国家,不仅拥有96075km^2的陆域疆土,还有近300万km^2的管辖海域,蕴藏着丰富的自然资源与巨大的空间资源。海洋,是国家战略资源基地、国家安全的海上屏障、贸易往来的必经之路,是沿海大都市区发展的重要依托、沿岸生态环境的支撑保障和未来生产与活动的空间,是开发潜力巨大的空间领域。未来 相似文献
212.
Observed residual currents off the Changjiang (Yangtze) Rivermouth in wintertime of 1959 and 1982 总被引:1,自引:0,他引:1
Data taken in the two large-scale ocean investigations in China in winter 1959 and 1982 are used to analyze the residual current off the Changjiang (Yangtze) River mouth in this paper. The current in wintertime off the river mouth consist of the Changjiang runoff, wind-driven current, coastal current, density-driven current and Taiwan Warm Current (TWC). The TWC occurs in wintertime off the mouth. The surface TWC reaches only to the east side of Dinghai, then turns southeastward. The bottom TWC can flow to the area off the Changjiang mouth along west slop of the submerged river valley (SRV) and to the area off the Subei coast, The simulated currents by 3D model are basically consistent with the observed currents, although the model was run with climatological forces and the observations was done in episodic time manner. 相似文献
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3月11日发生的9级强烈地震在日本东北太平洋沿岸引发巨大海啸,并产生了大面积的核泄漏,人员和财产损失惊人,再次给人类敲响了抵御重大地质灾难的警钟。天灾不可避免,但我们可以尽最大努力将灾害带来的损失降到最低。作为全球地质灾害最严重国家之一的中国,多年来十分重视潜在地质灾害隐患的预防,通过一系列法规、政策和相关措施,构建了一条抵御地质灾害的立体防线。 相似文献
218.
In this paper, the water waves and wave-induced longshore currents in Obaky coastal water which is located at the Mediterranean coast of Turkey were numerically studied. The numerical model is based on the parabolic mild-slope equation for coastal water waves and the nonlinear shallow water equation for the wave-induced currents. The wave transformation under the effects of shoaling, refraction, diffraction and breaking is considered, and the wave provides radiation stresses for driving currents in the model. The numerical results for the water wave-induced longshore currents were validated by the measured data to demonstrate the efficiency of the numerical model. Then the water waves and longshore currents induced by the waves from main directions were numerically simulated and analyzed based on the numerical results. The numerical results show that the movement of the longshore currents was different while the wave propagated to a coastal zone from different directions. 相似文献
219.
Remote sensing applications are important in the fisheries sector and efforts were on to improve the predictions of potential fishing zones using ocean color. The present study was aimed to investigate the phytoplankton dynamics and their absorption properties in the coastal waters of the southeastern Arabian Sea in different seasons during the year 2010 to 2011. The region exhibited 73 genera of phytoplankton from 19 orders and 41 families. The numerical abundance of phytoplankton varied from 14.235×103 to 55.075×106 cells/L. Centric diatoms dominated in the region and the largest family identified was Thalassiosiraceae with main genera as Skeletonema spp., Planktionella spp. and Thalassiosira spp. Annual variations in abundance of phytoplankton showed a typical one-peak cycle, with the highest recorded during premonsoon season and the lowest during monsoon season. The species diversity index of phytoplankton exhibited low diversity during monsoon season. Phytoplankton with pigments Chlorophyll a, Chlorophyll b, Chlorophyll c, peridinin, diadinoxanthin, fucoxanthin, β-carotene and phycoerythrobilin dominated in these waters. The knowledge on phytoplankton dynamics in coastal waters of the southeastern Arabian Sea forms a key parameter in bio-optical models of pigments and productivity and for the interpretation of remotely sensed ocean color data. 相似文献
220.
针对当前常用的低潮线提取方法不能适应较大区域范围的现状,提出一种基于曲面求交的低潮线提取方法。首先,在顾及潮滩带状分布特点的基础上,采用单向分区策略构建潮滩数字高程模型;然后,综合利用验潮站和网格潮汐模型计算的低潮面值,采用TCARI (the tidal constituent and residual interpolation)方法,构建曲面形态(连续无缝)的沿岸低潮面模型;最后,对所构的两个模型进行曲面求交,提取沿岸低潮线。试验结果表明,当提取低潮线的区域较大时,所提方法能明显提高低潮线的提取精度。 相似文献