近海工程环境应用中各种风资料的平均时间分析   总被引：5，自引：0，他引：5  

吴增茂  孙士才 《海岸工程》1995,14(3):8-12

本文从近海工程设计应用的需要出发，对于通常使用的不同来源的测风资料平均时间进行了分析，这些资料来源包括：岸边及近海探查与生产设施上的气象台站、天气观测船、浮标、商船气象报、从受灾情况估计出的极大风速以及动力诊断模型估计出的海面风速。  相似文献   

两种涡鞭毛藻的周日垂直迁移特性研究   总被引：3，自引：3，他引：3  

周名江  M. Elbrachter 《海洋与湖沼》1994,25(2):173-178

Ａｌｅｘａｎｄｒｉｕｍ ｌｕｓｉｔａｎｉｃｕｍ于１９８７年采自葡萄牙沿海，Ｙ－１００于１９８９年采自德国湾。在暗室中用一根柱长１５０ｃｍ，内径３．４ｃｍ的玻璃柱对两种涡鞭毛藻的垂直行特性进行研究。结果表明，两种藻均进行有规律的周日垂直迁移，且均在始前２ｈ开始向上迁移，光照结束前３ｈ开始向移速度约为２８０μｍ／ｓ，向下约为１４０μｍ／ｓ向下约为８５０μｍ／ｓ；Ｙ－１００向上迁移速度约为２８０μｍ／ｓ  相似文献   

台湾海峡金色小沙丁鱼幼鱼索饵群体研究   总被引：2，自引：1，他引：2  

杨圣云  丘书院 《台湾海峡》1992,11(3):244-250

本文研究了台湾海峡南部和北部的金色小沙丁鱼当年生幼鱼计数性状和量度性状特征差异,并结合其生物学特性、产卵场、洄游及海区环境特征进行综合分析。结果表明,台湾海峡南部和北部的索饵幼鱼仍属于同一地方种群:闽南-台湾浅滩语地方种群。根据其索饵洄游特点,可分为台湾海峡南部和北部两个索饵群体.  相似文献   

Coupling of life cycles of the copepods Calanus chilensis and Centropages brachiatus to upwelling induced variability in the central-southern region of Chile     

Pamela Hidalgo  Ruben Escribano 《Progress in Oceanography》2007,75(3):501-517

A time series of zooplankton sampling carried out at Station 18 off Concepción (36°S, 73°W) from August 2002 to December 2003 allowed the study of annual life cycles of the copepods Calanus chilensis and Centropages brachiatus in association with environmental variability in the coastal upwelling zone. Changes in the abundance of eggs, nauplii, and copepodids were assessed from samples taken at a mean time interval of ca. 20 days. Upwelling variability in near-surface waters was reflected in seasonal changes in salinity, water column stratification, and oxycline depth, as well as a weak seasonal signal in sea surface temperature (1-2 °C). Both copepods exhibited similar life cycles, characterized by continuous reproduction throughout the year. Estimates of generation times, as a function of temperature, were 25-30 days for C. chilensis and 27-35 days for C. brachiatus, predicting about 12 and 10 generations a year, respectively. These estimates were consistent with reproduction pulses observed in the field. It was thus suggested that copepods may grow under non-limiting food conditions in this upwelling area. However, despite continuous reproduction, there were abrupt changes in population sizes along with the disappearance of early naupliar and copepodid stages taking place even during the upwelling season (spring/summer). These changes were attributed to sudden increases in mortality taking place in spring or early summer, after which the populations remained at low levels through the fall and winter. It is thus suggested that, in addition to variability in the physical environment, biological interactions modulating changes in copepod mortality should be considered for understanding copepod life cycles in highly productive upwelling systems.  相似文献   

油田水动力系统与油气藏的形成   总被引：6，自引：0，他引：6  

陈建文  厉玉乐  孙德君  闫同生 《海洋地质与第四纪地质》1999,19(4):31-38

油田水中存在“沉积承压水”和“地表渗入水”两个相对独立而又相互作用的水动力系统,前者由上覆地层重量所引起的地静压力以及地静压力等引起的异常孔隙流体压力所形成,具有内循环承压式水交替特征,后者为大气降水和地表水向储集层的渗入而形成,以外循环渗入或水交替为特征。这两大系统（尤其是前者）的作用在很大程度上控制了含油气盆地中油气的运移、聚集和保存,油气聚集区主要位于水文地质带中的交管阻滞一停滞带内,沉积交替强度的低值区是油气富集区,沉积水的离心流使凹陷中的油气围绕凹陷中心呈带状分布。  相似文献   

Toward a generic method for studying water renewal, with application to the epilimnion of Lake Tanganyika   总被引：3，自引：0，他引：3  

Olivier Gourgue  Eric Deleersnijder  Laurent White   《Estuarine, Coastal and Shelf Science》2007,74(4):628

We present a method, based on the concept of age and residence time, to study the water renewal in a semi-enclosed domain. We split the water of this domain into different water types. The initial water is the water initially present in the semi-enclosed domain. The renewing water is defined as the water entering the domain of interest. Several renewing water types may be considered depending on their origin. We present the equations for computing the age and the residence time of a certain water type. These timescales are of use to understand the rate at which the water renewal takes place. Computing these timescales can be achieved at an acceptable extra computer cost.The above-mentioned method is applied to study the renewal of epilimnion (i.e. the surface layer) water in Lake Tanganyika. We have built a finite element reduced-gravity model modified to take into account the water exchange between the epilimnion and the hypolimnion (i.e. the bottom layer), the water supply from precipitation and incoming rivers, and the water loss from evaporation and the only outgoing river. With our water renewal diagnoses, we show that the only significant process in the renewal of epilimnion water in Lake Tanganyika is the water exchange between the epilimnion and the hypolimnion, other phenomena being negligible.  相似文献   

Migration and survival of farmed Atlantic salmon (Salmo salar L.) released from two Norwegian fish farms   总被引：1，自引：0，他引：1  

Hansen  Lars P. 《ICES Journal of Marine Science》2006,63(7):1211-1217

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Estimating migration rates from two tag-release/one recovery experiments   总被引：1，自引：0，他引：1  

Shirakihara  Kunio; Kitada  Shuichi 《ICES Journal of Marine Science》2004,61(5):821-828

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Interannual to diurnal variability in the near-surface scattering layer in Drake Passage     

Chereskin  T. K.; Tarling  G. A. 《ICES Journal of Marine Science》2007,64(9):1617-1626

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A phase-averaged Boussinesq model with effective description of carrier wave group and associated long wave evolution     

K. Nadaoka  K. Raveenthiran 《Ocean Engineering》2002,29(1):21-37

From the phase-resolving improved Boussinesq equations (Beji and Nadaoka, Ocean Engineering 23 (1996) 691), a phase-averaged Boussinesq model for water waves is derived by more effectively describing carrier wave groups and accompanying long wave evolution with less CPU time. Linear shoaling characteristics of carrier wave equations are investigated and found to agree exactly with the analytical expression obtained from the constancy of energy flux for the improved Boussinesq equations themselves, showing that the present model equations are the results of a consistent derivation procedure regarding energy considerations. Numerical simulations of the derived equations for the single wave group and narrow-banded random waves show the validity of the present model and its high performance, especially on the CPU time.  相似文献