Several significant hydrographic characteristics and their formation mechanism in the South China Sea during the spring and summer of 1998   总被引：1，自引：1，他引：1  

Xu Jianping  Chai Fei  Liu Zenghong  Zhu Bokang 《海洋学报(英文版)》2003,22(4):491-502

INTRODUCTIONTheSCSisthelargestmarginseainthewestoftheNorthPacificOcean .Theprevailingwindinwinterisnortheast,whileinsummeritissouthwest .Itisstilluncertainthathowthecirculationandtemperature -salinityfieldassociatewiththemonsoonforcingandaccompanywithseveralkindsofvariationsbeforeorafterthesummermonsoonburst .DuringSECMEXin 1 998,twointensiveobservationperiods (IOP)havebeencarriedoutntheSCS (Fig 1 ) :IOP1 ,from 1 0Aprilto 5May ;IOP2 ,from 1 2JunetoJuly 6 ,inordertounderstandthe…  相似文献   

The intertidal erosion rate of cohesive sediment: a case study from Long Island Sound   总被引：2，自引：0，他引：2  

Y. H. Wang   《Estuarine, Coastal and Shelf Science》2003,56(5-6):891-896

Over the past decades, many attempts have been made to generate useful bottom erosion models for the study of cohesive sediment movement. This study addresses some of the key questions involved in determining the functional relationship between erosion rate and bottom shear stress. Current, wave, and turbidity data were collected from a bottom mounted instrument array in a moderately energetic estuarine environment. The bottom shear stress was calculated from a wave–current interaction model. The erosion rate was derived from the observed sediment concentration using a vertical mixing model. Examination of the relationship between erosion rate and bottom stress showed that the erosion rate varied at intertidal frequency. When averaged over the tidal fluctuation, the erosion rate remained approximately constant at low stress, but increased sharply when the shear stress rose above a critical value. This suggests two-stage erosion. The bed has a layered structure, in which a thin layer of loose, high water content material overlies a more consolidated bed. The top layer of high water content material (fluff) was easily disturbed and re-suspended by tidal currents, but the consolidated bottom layer was eroded only under conditions of high shear stress.  相似文献   

海湾扇贝养殖群体遗传多样性的研究   总被引：13，自引：4，他引：13  

张喜昌  梁玉波  刘仁沿  王立俊  杨波 《海洋学报》2002,24(2):107-113

用等位基因酶的聚丙烯酰胺凝胶电泳技术,研究了大连沿岸不同生态环境条件下的大李家湾低排筏、大李家湾高排筏、凌水桥、棋盘磨4个海湾扇贝养殖群体的遗传多样性.在4个群体的7种等位基因酶和闭壳肌蛋白中均检测到了22个基因位点,各群体的多态位点比例分别为22.73%,22.73%,22.73%,18.18%(P≤0.95)和27.27%,27.27%,31.82%,36.36%(P≤0.99);杂合度观测值分别为0.064,0.071,0.075,0.069;Hardy-Weinberg平衡偏离指数分别为-0.068,-0.020,-0.032,-0.050;近交系数分别为0.568,0.565,0.487,0.550;位点等位基因有效数分别为1.102,1.109,1.143,1.122;遗传变异综合评价指数分别为0.0060,0.0071,0.0088,0.0073.海湾扇贝养殖群体遗传多样性总体水平较低,但在这4个群体中,凌水桥群体的遗传多样性水平最高,大李家湾高排筏和棋盘磨群体的遗传多样性水平较高,大李家湾低排筏群体遗传多样性水平最低.  相似文献   

AHP RESIN AND ITS URANIUM ADSORPTION MECHANISM     

蔡水源  庄明江  郑文庆 《海洋学报(英文版)》1982,1(2):225-233

I. INTRODUCTION AHP resin is a new type of adsorbent and has been studied by the units concernedfor several years. There is little report about this work so far. AHP resin was synthesizedin aqueous phase with tetra-ethylene pentamine (TEPA), epichlorohydrin (ECH) andC-reagent as raw materials, and basic zinc carbonate (P_Z_n) and rubber solvent oil (120Gasoline) as pore-forming material. Compared with the technique of the amorphous lumpresin and that of the resin synthesized in oil phase, the new technique of resin synthesizedin aqueous phase manifests many advantages, such as raising the capacity of uranium-adsorption of the resin, simplifying the after-treatment process, reducing the cost, etc. Sea water, in which all kinds of cation and anion exist, is a system of electrolytes,and the concentrations of many ions are higher than the concentration of uranium for  相似文献   

A COMPARATIVE STUDY OF 1982-1983 EL NIÑO EVENT     

张启文  王绍武 《海洋学报(英文版)》1986,5(4):517-521

The 1982-1983 El Niño event is examined in comparison with the other El Niño events in 1949-1983. The relationships of subtropical high to the sea surface temperature (SST) show the important influence of the atter, which vaired with the characters of El Niño events.  相似文献   

头足类视觉特性的电生理研究 Ⅰ.无针乌贼视网膜电图的特性   总被引：1，自引：0，他引：1  

郑微云  柴敏娟 《海洋学报》1981,3(3):472-476

乌贼是重要的海洋水产资源之一,对其视觉特性的研究在理论上和实践上显然都有一定的意义。视网膜电图(ERG)作为网膜的综合电活动是反映视觉特性的一个良好指标。乌贼的ERG的特性至今缺乏系统的研究。本文对其ERG的波形和适应特性作了较详细的描述。续文将报导对ERG的光谱敏感性的分析。  相似文献   

网格剖分积分法计算富钴结壳资源量     

吴自银  初凤友  马维林  李守军 《海洋学报》2007,29(5):81-87

在矿区地质模型建立及边界条件限定的基础上,提出了基于网格剖分积分计算富钴结壳资源量的评估计算方法,推导了相应的计算公式,设计了相应的模块界面,并在"海底地形地貌自动成图系统"中实现了这种计算方法.这种资源量计算方法可应用于富钴结壳资源研究和评价计算.  相似文献   

迟缓爱德华氏菌及其致病机理     

王波  莫照兰 《海洋科学集刊》2007,(48):133-139

迟缓爱德华氏菌(Edwardsiella tarda)是一种革兰氏阴性肠道病原菌,感染宿主范围广。在水产养殖生物中,该菌是鱼类(鳗、鲇、鲆等)、两栖类(蛙)、爬行类(鳖、鳄鱼)的重要致病菌。爱德华氏菌病(Edwardsiellosis)是水产养殖中最常见的传染病之一,影响了养殖生物的健康并对水产养殖业危害巨大。随着对迟缓爱德华氏菌致病性研究的深入,对该病原致病因子相关研究取得了一些进展。研究发现一些胞外酶和毒素与细菌的致病过程有关,相关的致病因子有溶血素、软骨素醇、皮下坏死毒素、过氧化氢酶等。这些致病因子参与了细菌的黏附、定殖、侵袭和在宿主体内的繁殖和扩散过程。但从总体而言,对迟缓爱德华氏菌致病因子组成及其致病机制尚缺乏系统深入的研究。最近的研究发现了一种新的致病因子——Ⅲ型分泌系统;迟缓爱德华氏菌的Ⅲ型分泌系统仅存在于致病菌株.而在非致病株中没有发现,与细菌的致病性密切相关,它的出现为人们对迟缓爱德华氏菌的致病性的了解提供了新的视角。  相似文献   

具有内波特性的渤海南部次重力波     

范植松  高郭平  尹训强  范宇  吴玮 《海洋学报》2003,25(5):136-140

次重力波(infragravity waves)是频率范围介于局地平均Brunt-V¾is¾l¾频率和0.05Hz(涌浪频率)之间的一种海洋波动,其能量在深水大洋中一般甚低,但在浅海中却很强.该波动的研究对于浅海海洋内部混合、近岸海洋工程、海洋生态学、海洋沉积学及军事海洋学均有重要的意义.Munk[1]很早就开始研究这类波动,然而主要由于观测技术的限制,对于该类波动的动力学机制的研究进展迟缓.  相似文献   

Terrestrial and Submerged Aquatic Vegetation Mapping in Fire Island National Seashore Using High Spatial Resolution Remote Sensing Data     

Yeqiao Wang  Michael Traber  Bryan Milstead  Sara Stevens 《Marine Geodesy》2007,30(1):77-95

The vegetation communities and spatial patterns on the Fire Island National Seashore are dynamic as the result of interactions with driving forces such as sand deposition, storm-driven over wash, salt spray, surface water, as well as with human disturbances. We used high spatial resolution QuickBird-2 satellite remote sensing data to map both terrestrial and submerged aquatic vegetation communities of the National Seashore. We adopted a stratified classification and unsupervised classification approach for mapping terrestrial vegetation types. Our classification scheme included detailed terrestrial vegetation types identified by previous vegetation mapping efforts of the National Park Service and three generalized categories of high-density seagrass, low-density seagrass coverages, and unvegetated bottom to map the submerged aquatic vegetation habitats. We used underwater videography, GPS-guided field reference photography, and bathymetric data to support remote sensing image classification and information extraction. This study achieved approximately 82% and 75% overall classification accuracy for the terrestrial and submnerged aquatic vegetations, respectively, and provided an updated vegetation inventory and change analysis for the Northeast Coastal and Barrier Network of the National Park Service.  相似文献