连云港近岸海域物理自净能力研究及水质预测——Ⅲ.西大堤建成后对物质输运的影响     

赵可胜  娄安刚  王学昌 《中国海洋大学学报(自然科学版)》1994,(Z1)

在连云港近岸海域计算潮流场基础上建立拉格朗日余流模型,并对连云港市两大堤建成前后的拉格朗日余流变化进行了分析,且选择有代表性的排污口进行了数值跟踪。  相似文献   

Sediment Transport in Rivers and Coastal Waters     

YANG  Shu-qing 《中国海洋工程》2003,17(4):527-540

Following Bagnold's approach, a relationship between sediment transport and energy dissipation is developed. The major assumption made in the study is that the near bed velocity plays a dominant role in the process of sediment transport. A general relationship between energy dissipation and sediment transport is first proposed. Then the equations for total sediment transport are derived by introducing the appropriate expression of energy dissipation rate under different conditions, such as open channel flows, combination of wave and current, as well as longshore sediment transport. Within the flows investigated, the derived relationships are fairly consistent with the available data over a wide range of conditions.  相似文献   

Numerical study of enhanced energy dissipation near a seamount     

Nobuyuki Iwamae  Toshiyuki Hibiya  Yoshihiro Niwa 《Journal of Oceanography》2006,62(6):851-858

Using a two-dimensional primitive equation model, we examine nonlinear responses of a semidiurnal tidal flow impinging on a seamount with a background Garrett-Munk-like (GM-like) internal wavefield. It is found that horizontally elongated pancake-like structures of high vertical wavenumber near-inertial current shear are created both in the near-field (the region over the slope of the seamount) and far-field (the region over the flat bottom of the ocean). An important distinction is that the high vertical wavenumber near-inertial current shear is amplified only at mid-latitudes in the far-field (owing to a parametric subharmonic instability (PSI)), whereas it is amplified both at mid-and high-latitudes (above the latitude where PSI can occur) in the near-field. In order to clarify the generating mechanism for the strong shear in the near-field, additional numerical experiments are carried out with the GM-like background internal waves removed. The experiments show that the strong shear is also created, indicating that it is not caused by the interaction between the background GM-like internal waves and the semidiurnal internal tides. One possible explanation is proposed for the amplification of high vertical wavenumber near-inertial current shear in the near-field where tide residual flow resulting from tide-topography interaction plays an important role in transferring energy from high-mode internal tides to near-inertial internal waves.  相似文献   

A simple model to calculate the residual flows in a Spanish ria. Hydrographic consequences in the ria of Vigo     

Ricardo Prego  Fernando Fraga 《Estuarine, Coastal and Shelf Science》1992,34(6)

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东太平洋多金属结核分布的二维趋势面分析   总被引：1，自引：0，他引：1  

章伟艳  张富元  马维林 《海洋学研究》2001,19(1):27-34

对规则网的 469个测站的多金属结核丰度和 93个测站的 Mn、 Cu、 Co、 Ni元素进行趋势面分析 ,经 F检验 ,各变量的变异性显著 ,拟合度较低 ,表明多金属结核丰度及 Mn、Cu、Co、Ni金属元素的控制因素比较复杂。趋势面分析结果与相关分析结果一致 ,Mn、Cu、Ni元素有极相似的趋势特征 ,有两个轴向分布 ,一个为东西向轴 ,高值区在东部 ,另一个为北西向轴 ,高值区在北西部 ;结核丰度与 Co也有极相似的趋势特征 ,高值区在西部。应用逐次趋势面分析的结果将结核丰度的地质特征分解成各种简单控制因素的叠加 ,使对多金属结核的控矿因素、分布规律和物质来源的研究方法多样化  相似文献   

A preliminary study of carbon system in the East China Sea   总被引：1，自引：0，他引：1  

Shizuo Tsunogai  Shuichi Watanabe  Junya Nakamura  Tsuneo Ono  Tetsuro Sato 《Journal of Oceanography》1997,53(1):9-17

In the central part of the East China Sea, the activity of CO₂ in the surface water and total carbonate, pH and alkalinity in the water column were determined in winter and autumn of 1993. The activity of CO₂ in the continental shelf water was about 50 ppm lower than that of surface air. This decrease corresponds to the absorption of about 40 gC/m²/yr of atmospheric CO₂ in the coastal zone or 1 GtC/yr in the global continental shelf, if this rate is applicable to entire coastal seas. The normalized total carbonate contents were higher in the water near the coast and near the bottom. This increase toward the bottom may be due to the organic matter deposited on the bottom. This conclusion is supported by the distribution of pH. The normalized alkalinity distribution also showed higher values in the near-coast water, but in the surface water, indicating the supply of bicarbonate from river water. The residence time of the East China Sea water, including the Yellow Sea water, has been calculated to be about 0.8 yr from the excess alkalinity and the alkalinity input. Using this residence time and the excess carbonate, we can estimate that the amount of dissolved carbonate transported from the coastal zone to the oceanic basin is about 70 gC/m²/yr or 2 GtC/yr/area-of-global-continental-shelf. This also means that the rivers transport carbon to the oceans at a rate of 30 gC/m²/yr of the coastal sea or 0.8 GtC/yr/ area-of-global shelf, the carbon consisting of dissolved inorganic carbonate and terrestrial organic carbon decomposed on the continental shelf.  相似文献   

光照强度对海洋微藻脂肪含量及脂肪酸组成影响的研究   总被引：1，自引：0，他引：1  

李荷芳  周汉秋 《海洋科学集刊》2001,(43):178-183

近年来，海洋微藻脂肪酸组成的研究及其应用越来越受到国内外科学家的重视。高度不饱和脂肪酸(PUFA)，特别是长链的n-3 PUFA，如二十碳五烯酸(EPA)和二十二碳六烯酸(DHA)对海洋动物和人类都具有营养学和医学上的价值。在海洋微藻的培养过程中，光照强度是海洋微藻生长的条件之一，光线的明与暗，光度的强与弱，不仅对微藻的生长速率、产量有影响，而且对其脂肪含量和脂肪酸的组成也有影响(Teshima et al.，1983；Thompson et al.，1990； Renaud et al., 1991)。 作者在以往研究的基础上，选择了3种有代表性的海洋微藻：(1)小球藻Chlorella sp-2(李荷芳等，1999)，此藻脂肪酸中EPA含量高、且不含DHA；(2)球等鞭金藻(Isochrysis galbana)，该藻DHA含量较高，但几乎不含EPA；(3)前沟藻(Amphidinium sp.)的EPA、DHA含量均高。将以上3种微藻作为原料，在不同的光照强度下进行培养，测定并分析藻体中的脂肪含量和脂肪酸组成的变化，从而了解光强对海洋微藻脂肪含量及其脂肪酸组成的影响。  相似文献   

Predicting total allowable catches for Icelandic capelin, 1978-2001     

Gudmundsdottir  Asta; Vilhjalmsson  Hjalmar 《ICES Journal of Marine Science》2002,59(5):1105-1115

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渤海湾、黄河口和长江口海域海水中颗粒氨基酸含量的分布   总被引：2，自引：0，他引：2  

张星君  纪明侯 《海洋科学集刊》2004,46(46):91-99

海水中除含有大量无机物质外，还含有种类繁多，但含量很低的有机物质，其含量约为C 0.5-2.0mg/L。海水有机物质可分为溶解有机物质(DOM)和颗粒有机物质(POM)。前者为主要组分，后者所含比例很小。在大洋中POM的主要来源有:①浮游生物，尤其是浮游植物活体、死骸及其分解碎屑;②海水中进行的DOM-POM的动力平衡产物。近岸海水还受河流流入的陆地POM和大气带入的陆源尘埃的影响。POM主要由蛋白质、碳水化合物、脂类等组成。POM是食碎屑动物的良好食物，它构成海洋食物链的一环，与水域生物生产力有直接的联系。POM中蛋白质含量以颗粒氨基酸(PAA)表示。Daumas(1976)曾报道过沿岸海水中PAA含量的季节变异，纪明侯等(1992年)于1980-1981年首次对青岛胶州湾内PAA含量在不同站位和不同季节中的变化特征进行调査研究。作者等继而于1982年7月、1983年10月和1984年5、7、8月乘“金星二号”考察船前后首次研究了渤海湾、黄河口和长江口附近水域中颗粒氨基酸的组成与含量在不同站位中的分布。所得结果如下。  相似文献   

十四株海洋微藻脂肪酸组成的研究   总被引：5，自引：0，他引：5  

张小葵  麦康森  郭健  孙世春 《中国海洋大学学报(自然科学版)》2001,31(2):205-210

对 4个门的 14株 (红藻门 8株 ,甲藻门 1株 ,隐藻门 2株 ,绿藻门 3株 )海洋微藻进行了脂肪酸含量测定 ,微藻在确定的条件下生长 ,指数生长末期收获。结果表明 ,各门的微藻都有其独特的脂肪酸特征 :红藻中含有大量的 2 0 :4 n- 6和 2 0 :5n- 3,其中紫球藻 R2 5含量最高 ,占总脂肪酸的4 9.8% (AA占总脂肪酸的 2 0 .5% ,EPA占总脂肪酸的 2 9.3% )。隐藻的主要脂肪酸是 16 :0、18:1n- 9、18:3n- 3、18:4 n- 3、2 0 :5n- 3、2 2 :5n- 3。与其它甲藻有别的虫黄藻 ,18:4 n- 3含量很少并且不含EPA,其主要合成的是 16 :0、18:1n- 9和 2 2 :6 n- 3。 C16和 C18的不饱和脂肪酸是本实验研究的 3株绿藻的主要脂肪酸  相似文献