分潮波模型多资料数值计算方法研究　Ⅰ.岸边资料运动学外推的第一边值方法     

潘文波  孙文心 《中国海洋大学学报(自然科学版)》1996,(1)

对于含多资料三维分潮波模型建立了一种岸边资料运动学外推的潮波第一边值方法，并对渤海的四大原湖波进行试算。结果证实本方法可行，该方法使潮波方程既满足第一边值问题，充分利用岸边测站资料，又保证岸界法向流速为零条件，符合物理意义。并对复型病态矩阵的收敛问题提出了一种可行性处理。  相似文献   

Evidence for the grazing hypothesis: Grazing reduces phytoplankton responses of the HNLC ecosystem to iron enrichment in the western subarctic pacific (SEEDS II)     

《Journal of Oceanography》2007,63(6):983-994

A mesoscale iron-enrichment study (SEEDS II) was carried out in the western subarctic Pacific in the summer of 2004. The iron patch was traced for 26 days, which included observations of the development and the decline of the bloom by mapping with sulfur hexafluoride. The experiment was conducted at almost the same location and the same season as SEEDS (previous iron-enrichment experiment). However, the results were very different between SEEDS and SEEDS II. A high accumulation of phytoplankton biomass (∼18 mg chl m⁻³) was characteristic of SEEDS. In contrast, in SEEDS II, the surface chlorophyll-a accumulation was lower, 0.8 to 2.48 mg m⁻³, with no prominent diatom bloom. Photosynthetic competence in terms of F _v/F _m for the total phytoplankton community in the surface waters increased after the iron enrichments and returned to the ambient level by day 20. These results suggest that the photosynthetic physiology of the phytoplankton assemblage was improved by the iron enrichments and returned to an iron-stressed condition during the declining phase of the bloom. Pico-phytoplankton (<2 μm) became dominant in the chlorophyll-a size distribution after the bloom. We observed a nitrate drawdown of 3.8 μM in the patch (day 21), but there was no difference in silicic acid concentration between inside and outside the patch. Mesozooplankton (copepod) biomass was three to five times higher during the bloom-development phase in SEEDS II than in SEEDS. The copepod biomass increased exponentially. The grazing rate estimation indicates that the copepod grazing prevented the formation of an extensive diatom bloom, which was observed in SEEDS, and led to the change to a pico-phytoplankton dominated community towards the end of the experiment.  相似文献   

中国多金属结核开辟区东、西两小区小型底栖动物的空间分布   总被引：1，自引：1，他引：1  

高爱根  王春生  杨俊毅  王自磐  何德华 《海洋学研究》2002,20(1):28-35

利用 1 998年“大洋一号”调查船 DY95 - 8航次在中国多金属结核开辟区东、西两小区用多管取样器采集的沉积物样品 ,对小型底栖动物的组成、分布及其与环境因子的关系进行了研究。结果表明 :(1 )东、西两小区共有 1 6个类群的小型底栖动物 ,其中线虫类占居显著优势 ,在东、西两小区各占总栖息密度的 71 %和 6 4 %,其次为猛水蚤类和蜱螨类。 (2 )东、西两小区小型底栖动物类群平均栖息密度分别为 3 2 .47ind/1 0 cm2 和 1 8.0 5 ind/1 0 cm2 ,东小区高于西小区。小区各站位间的栖息密度平面分布差异显著。 (3 )东、西两小区小型底栖动物类群栖息密度的垂直分布趋势明显 ,由表层向底层 ,栖息密度逐渐降低。 (4)东、西两小区小型底栖动物空间分布与底质沉积物、结核覆盖率和底层流等环境因子密切相关 ,底质较硬、结核覆盖率较高以及底层流较强都不利于小型底栖动物的栖息。  相似文献   

龙口的海风及其影响   总被引：4，自引：0，他引：4  

薛德强  赵绪孔 《海洋湖沼通报》1995,(3):1-9

本文运用龙口气象站近５年自记风资料及实测探空资料，分析了龙口海风的生消规律、海风强度、空间结构及海风生成后对温、湿度的影响。同时为分析海风环流对大气污染物的影响。本文提出了一个简单地计算热内边界层的方法。  相似文献   

Diet of Phycis blennoides (Gadidae) in Relation to Fish Size and Season in the Western Mediterranean (Spain)     

Maria Salomé Morte  Manuel J. Redón  & Antonio Sanz-Brau 《Marine Ecology》2002,23(2):141-155

Abstract. Despite its commercial value, little is known about the feeding ecology of the greater forkbeard, Phycis blennoides (Brünnich 1768). The stomach contents of 2631 greater forkbeard were taken at monthly intervals off the coast of the Gulf of Valencia (western Mediterranean). They were examined in order to assess the diet and to determine the fish size- and season-related dietary variation of the species. Prey items were identified to the lowest taxonomic level possible. The basic food consisted of epibenthic species, mostly Decapoda, Mysidacea and Teleostei. A change in food composition based on fish size was observed and seasonal variation in diet was also recorded. The food overlap analysis indicated a high convergence in diet among similar size groups.  相似文献   

Responses of carbon dioxide in western tropical Pacific to 1991~1993 ENSO event     

Ma Liming 《海洋学报(英文版)》1997,16(2):201-214

On the basis of the data of the partial pressure of CO₂ (P_CO2)and the concentration of the total dissolved CO₂(T_CO2) in surface water during the expeditions in Nov.-Dec. 1991, the world ocean circulation experiment (WOCE) and Oct. 1992-Mar. 1993, the tropical ocean-global atmosphere coupled ocean-atmosphere response experiment (TOGA COARE) in the western tropical Pacific and of the comparison with data from 1986 to 1990 TOGA expeditions and that from Japan Meteorological Agency, the response of CO₂ in surface water to ENSO event is proved. The CO₂ signals indicated that the air-sea system in the western and central tropical Pacific from 1991 to 1993, except for a short period in autumn of 1992, was in a strong state of ENSO.
The change of CO₂ in the floating stations near 2°S, 155°E from Nov. 1992 to Mar. 1993 reflected the change of currents, water mass and its thermal and salt content during the forming and developing of ENSO.  相似文献   

P矢量方法在南海夏季环流诊断计算中的应用   总被引：8，自引：4，他引：8  

卜献卫  袁耀初  刘勇刚 《海洋学报》2001,23(3):8-17

基于1998年6～7月南海调查航次的CTD资料,对南海环流采用最近发展的P矢量方法进行诊断计算.计算结果:黑潮向西入侵南海,然后做反气旋弯曲向东北方向流动,最终有通过巴士海峡流出南海的趋势.在南海北部存在一个气旋性环流,这个环流的强度和范围随深度增加而减小.该环流的冷中心位置随深度增加稍向南移.南海中部、越南以东海域存在一个明显的气旋涡和反气旋涡,尤其在200m及其以上水层均相当稳定,反气旋涡位于越南以东,其中心位置在11°53'N,111°50'E,气旋涡的中心位置在13°17'N,112°55'E,两者的尺度皆约为250km.吕宋岛西侧存在一个反气旋涡.在计算海区南部、巴拉望岛西南海域,100m以上层存在一个反气旋式涡.从各层流场分布均可以显示海流在西部强化的现象.  相似文献   

Modified mild slope equation and open boundary conditions     

M. C. Khellaf  M. Bouhadef 《Ocean Engineering》2004,31(13):1713-1723

A numerical model to compute wave field is developed. It is based on the Berkhoff diffraction-refraction equation, in which an energy dissipation term is added, to take into account the breaking and the bottom friction phenomena. The energy dissipation function, by breaking and by bottom friction, is introduced in the Berkhoff equation to obtain a new equation of propagation.The resolution is done with the hybrid finite element method, where lagrangians elements are used.  相似文献   

Geodynamic Evolution of the Eastern Segment of the Azores-Gibraltar Zone: The Gorringe Bank and the Gulf of Cadiz Region     

Tortella  D.  Torne  M.  Pérez-Estáun  A. 《Marine Geophysical Researches》1997,19(3):211-230

Detailed structural interpretation of the recently acquired deep seismic multichannel profiles along the Iberian Atlantic Margins (IAM Project) provides new results on the geodynamic evolution of the eastern part of the Azores-Gibraltar plate boundary. Thrusting and folding of the oceanic basement and of Mesozoic and Cenozoic sedimentary cover of the Gorringe Bank region are consistent with the N–S convergence of Iberia and Africa. Compressive structures in the Gorringe Bank region are spread over a wide area. Deformation under compression took place mainly in Tertiary times, as is evidenced by a basal unconformity and several discontinuities in Tertiary sediments, although some deformation has also been recorded in Quaternary sediments. The compressive structures in the Gulf of Cadiz are E–W oriented thrusts, folds and related diapiric structures. N–S oriented transpressive deformation is likely to occur in the western Portuguese platform. There is no continuity of structures from the oceanic to the continental domain, suggesting that deformation transfers from one side to the other through a transcurrent fault zone. The fault contact between the two domains is located in the ocean-continent transition zone.  相似文献   

Comparing the Benguela and Humboldt marine upwelling ecosystems with indicators derived from inter-calibrated models   总被引：10，自引：0，他引：10  

Moloney  Coleen L.; Jarre  Astrid; Arancibia  Hugo; Bozec  Yves-Marie; Neira  Sergio; Roux  Jean-Paul; Shannon  Lynne J. 《ICES Journal of Marine Science》2005,62(3):493-502

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