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921.
我国海洋自然保护区的发展和分布特征分析   总被引:1,自引:0,他引:1  
对我国海洋自然保护区发展动态和分布特征进行了分析.根据海洋自然保护区的数量和面积,将其发展过程划分为零发展、零星发展、停滞发展、恢复与快速发展和高速发展5个阶段.基于遥感信息,文章绘制了我国海洋自然保护区分布图,并深入分析了海洋自然保护区的行政分布、类型分布和地理分布的特征.文章还分析了影响海洋自然保护区发展与分布的因素.  相似文献   
922.
《海洋测绘》2008,28(5):I0001-I0001
中国测绘学会第七届海洋测绘专业委员会第四次全体会议暨第二十届海洋测绘综合性学术研讨会,于2008年9月10~15日在青海省西宁市召开。  相似文献   
923.
海洋油气开发与安全保障工程研究中心于2007年获教育部批准立项建设,坐落在中国海洋大学崂山校区。中心旨在满足国家油气资源中长期发展要求,围绕海洋油气勘探开发中急需解决的关键性技术难题。  相似文献   
924.
有关地中海海洋系统对气候效应的灵敏性这一问题仍处于争辩阶段。在这里,我们研究了在过去最后两个间冰期高峰期间东地中海海洋循环对日照效应的长期反应,在这期间大规模的水文变化导致了富含有机质的沉积物的沉积。  相似文献   
925.
泥质角砾相/流是识别泥火山的一个主要特征:角砾沉积的时间意味着泥火山的喷发历史,而角砾出现的规模表示了泥火山的强度。库拉泥火山位于地中海东部阿那克西曼德海山北缘水深1750m处,圆丘状。多波束及深拖旁侧声纳系统调查显示,库拉泥火山北向及峰顶具有比周围区域高的背向散射强度。  相似文献   
926.
为了识别和掌握冷泉活动,大量的调查正在卡拉布里亚岛弧增生棱柱体开展。2005年夏天,意大利“OGS勘探者”号调查船在卡拉布里亚岛弧海区中发现了多处冷泉活动,现在已经被2006和2007年深入开展的两个海洋科学调查航次所证实(调查船分别为R/VMeter和R/VPourquoisPas)。  相似文献   
927.
Two Large-insert genomic bacterial artificial chromosome (BAC) libraries of Zhikong scallop Chlamys farreri were constructed to promote our genetic and genomic research. High-quality megabase-sized DNA was isolated from the adductor muscle of the scallop and partially digested by BamH I and Mbo I, respectively. The BamH I library consisted of 53 760 clones while the Mbo I library consisted of 7 680clones. Approximately 96 % of the clones in BamH I library contained nuclear DNA inserts in average size of 100 kb, providing a coverage of 5.3 haploid genome equivalents. Similarly, the Mbo I library with an average insert of 145 kb and no insert-empty clones, thus providing a genome coverage of 1.1 haploid genome equivalents.  相似文献   
928.
Partial pressure of CO2(pCO2) was investigated in the Changjiang(Yangtze River) Estuary,Hangzhou Bay and their adjacent areas during a cruise in August 2004,China.The data show that pCO2 in surface waters of the studied area was higher than that in the atmosphere with only exception of a patch east of Zhoushan Archipelago.The pCO2 varied from 168 to 2 264 μatm,which fell in the low range compared with those of other estuaries in the world.The calculated sea-air CO2 fluxes decreased offshore and varied from -10.0 to 88.1 mmol m-2 d-1 in average of 24.4 ± 16.5 mmol m-2 d-1.Although the area studied was estimated only 2 × 104 km2,it emitted(5.9 ± 4.0) × 103 tons of carbon to the atmosphere every day.The estuaries and their plumes must be further studied for better understanding the role of coastal seas playing in the global oceanic carbon cycle.  相似文献   
929.
Wave breaking on turbulent energy budget in the ocean surface mixed layer   总被引:2,自引:0,他引:2  
As an important physical process at the air-sea interface, wave movement and breaking have a significant effect on the ocean surface mixed layer (OSML). When breaking waves occur at the ocean surface, turbulent kinetic energy (TKE) is input downwards, and a sublayer is formed near the surface and turbulence vertical mixing is intensively enhanced. A one-dimensional ocean model including the Mellor-Yamada level 2.5 turbulence closure equations was employed in our research on variations in turbulent energy budget within OSML. The influence of wave breaking could be introduced into the model by modifying an existing surface boundary condition of the TKE equation and specifying its input. The vertical diffusion and dissipation of TKE were effectively enhanced in the sublayer when wave breaking was considered. Turbulent energy dissipated in the sublayer was about 92.0% of the total depth-integrated dissipated TKE, which is twice higher than that of non-wave breaking. The shear production of TKE decreased by 3.5% because the mean flow fields tended to be uniform due to wave-enhanced turbulent mixing. As a result, a new local equilibrium between diffusion and dissipation of TKE was reached in the wave-enhanced layer. Below the sublayer, the local equilibrium between shear production and dissipation of TKE agreed with the conclusion drawn from the classical law-of-the-wall (Craig and Banner, 1994).  相似文献   
930.
Primary production in the Bering and Chukchi Seas is strongly influenced by the annual cycle of sea ice. Here pelagic and sea ice algal ecosystems coexist and interact with each other. Ecosystem modeling of sea ice associated phytoplankton blooms has been understudied compared to open water ecosystem model applications. This study introduces a general coupled ice-ocean ecosystem model with equations and parameters for 1-D and 3-D applications that is based on 1-D coupled ice-ocean ecosystem model development in the landfast ice in the Chukchi Sea and marginal ice zone of Bering Sea. The biological model includes both pelagic and sea ice algal habitats with 10 compartments: three phytoplankton (pelagic diatom, flagellates and ice algae: D, F, and Ai) , three zooplankton (copepods, large zooplankton, and microzooplankton : ZS, ZL, ZP) , three nutrients ( nitrate + nitrite, ammonium, silicon : NO3 , NH4, Si) and detritus (Det). The coupling of the biological models with physical ocean models is straightforward with just the addition of the advection and diffusion terms to the ecosystem model. The coupling with a multi-category sea ice model requires the same calculation of the sea ice ecosystem model in each ice thickness category and the redistribution between categories caused by both dynamic and thermodynamic forcing as in the physical model. Phytoplankton and ice algal self-shading effect is the sole feedback from the ecosystem model to the physical model.  相似文献   
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