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81.
Four enzymes and one protein were tested in starch and cellulose acetate gels as biochemical tags for the separation of flounder (Rhombosolea spp.) larvae and O‐groups. Lactate dehydrogenase phenotypes separated O‐groups and larvae (longer than about 5 mm) of R. plebeia from R. leporina and R. retiaria. General protein phenotypes separated similar specimens of R. leporina from R. plebeia and R. retiaria. Most Rhombosolea larvae and O‐groups caught in Wellington Harbour were R. plebeia.  相似文献   
82.
The Texas and Coffs Harbour oroclines are defined by a Z-shaped curvature in the southern New England Orogen (eastern Australia), but the geometry and kinematics of faults around these oroclines, as well as their possible role during oroclinal bending, have hitherto not been understood. Using aeromagnetic and open file seismic data, as well as field observations, the pattern, geometry and kinematics of fault systems, have been investigated. Fault traces with a strike-slip component are oriented parallel to the curved magnetic and structural fabrics of the Texas and Coffs Harbour oroclines. Our observations show evidence for sinistral or sinistral-reverse, dextral (or dextral-reverse) and normal kinematics along NW-striking faults. The dominant kinematics along NNE- and NE-striking faults is dextral or dextral-reverse. The timing of faulting is not well constrained, but the ubiquitous recognition of orocline-parallel faults may suggest that a flexural slip mechanism operated during oroclinal bending in the early–middle Permian (ca 299–265 Ma). Our observations indicate that many of the orocline-parallel faults, with strike-slip separation, were reactivated during the Mesozoic and Cenozoic, as indicated by the recognition of displaced Triassic granitoids, Mesozoic sedimentary rocks and Cenozoic basalts.  相似文献   
83.
象山港分区水交换数值研究   总被引:5,自引:1,他引:4  
姚炎明  彭辉  杜雅杰  刘莲 《海洋学报》2014,36(1):126-130
在验证良好的三维斜压潮流数学模型的基础上,将象山港划分成7个海区,以7种不同的溶解态保守性物质为示踪剂,建立对流-扩散型的海湾水交换数值模型,采用关联矩阵法来描述各区之间以及各区与外海之间的水交换特性。通过不同示踪剂的浓度分布,计算了15、30、45、60和80d的水交换矩阵。由各时刻水交换矩阵可知,在象山港的7个子区中与湾外水的水交换速度最快的为Ⅰ区,最慢的为Ⅶ区。Ⅲ区(西沪港)、Ⅵ区(黄墩港)和Ⅶ区(铁港)内水体与湾外海水之间的水交换速度缓慢,但与区域外水体之间的交换速度要明显快于其他几个海区。从水交换矩阵可以看出西沪港、黄墩港和3个内港之间相互交换的海水量很小。  相似文献   
84.
The Great Barrier Reef (GBR), Queensland, Australia, is one of the most recognisable coral reefs in the world. In 1981 the reef was listed on the World Heritage List, to be preserved as an environmental asset of global significance for all people in perpetuity. The GBR is also a landmark Marine Protected Area (MPA) under the World Heritage Marine Programme. Yet management of this iconic property is not without controversy and in recent years a number of impacts, including coastal developments, increased shipping traffic and global warming, have all threatened the reef. Any breach of Australia's World Heritage obligation to protect and conserve the property may yet result in the GBR being placed on the World Heritage List in Danger. In light of the persistent controversy surrounding GBR management, this paper gives voice to the perspectives and values of stakeholders located in and around one site of controversy, Gladstone Harbour, in the southern section of the GBR World Heritage Area. We present the views of users directly exposed to the controversial port expansion development at Gladstone Harbour in the southern GBR to shed light on the importance of community perspectives in marine park management. Our findings show that local views act to reinforce the global environmental protection narrative which underpins the World Heritage (WH) system. In this study local and global values collide and, we argue, that overlooking the perspectives of users has potential deleterious consequences for WH marine site management.  相似文献   
85.
On the banks of the Garonne River at Bordeaux, the discovery of three antique and medieval harbour platforms situated below the highest spring tide level (HWS) is witnessed to its increase of 1.10 m between the 12th and 14th centuries. It was then identified during excavations in the port of London and along the southern coast of the North Sea. In another direction, European studies suggest the consequences of such a sea level rise by identifying submerged ancient and medieval sites. This increase can be correlated to climatic oscillations, both regional and global, as has been identified by dendroclimatology. This centennial increase has not been accepted as an integral part of the curve expressing the maritime contour line over a period of thousands of years. This latter curve tends to smooth out oscillations in the order of a century and regional scale. To conclude, this medieval increase is comparable to that attested during the 20th century; this permitting a modulation of the importance of the anthropic component on the latter. To cite this article: T. Gé et al., C. R. Geoscience 337 (2005).  相似文献   
86.
模拟研究厦门港员当湖重污染疏浚物中Pb向海水的释放作用。Pb的释放过程非常缓慢,平衡时间约15—20d,平衡释放率在2%左右,溶出平衡浓度为1μg/L。提供两种动力学模式,分别测定溶出速率常数、表观活化能和平衡分配系数。研究表明,在一般疏浚物的海上倾倒过程中,颗粒Pb的释放对海水水质不致产出明显影响。  相似文献   
87.
海南岛三亚港现代沉积速率的研究   总被引:8,自引:0,他引:8  
对1988年所采集的海南岛三亚港6个沉积柱样作了沉积结构及^210Pb放射性分析。结果表明,三亚港潮汐通道及航道上,沉积物主要为细颗粒的粉砂、粘土,沉积速率为0.91-1.24cm/a,近年来砂质物的输入,反映了疏浚等人类活动对该区的影响;外港浅滩砂洲区的沉积速率小于0.4cm/a;潮汐通道中过剩^210Pb总量亦明显大于港口的其它区域。  相似文献   
88.
Surface water waves in coastal waters are commonly modeled using the mild slope equation. One of the parameters in the coastal boundary condition for this equation is the direction at which waves approach a coast. Three published methods of estimating this direction are examined, and it is demonstrated that the wave fields obtained using these estimates deviate significantly from the corresponding analytic solution. A new method of estimating the direction of approaching waves is presented and it is shown that this method correctly reproduces the analytic solution. The ability of these methods to simulate waves in a rectangular harbor is examined.  相似文献   
89.
左浩  高抒 《海洋通报》2005,24(1):8-17
采用一个包括陆地淡水径流和风暴潮影响的模型计算了海南省博鳌港的洪水水位。模型中的外海潮汐考虑K^1和O^1分潮,风暴增水和河流流量的变化过程采用峰值函数的形式模拟,取得了与实测结果相近的计算结果。模拟实验表明,洪水水位峰值与河流洪峰流量,风暴增水峰值,系统的过水断面形状以及洪水历时的长短等因素有关。对于博鳌港口门通航条件整治,采用复合的梯形过水断面最为合适,因为相对于天然的口门过水断面,复合梯形断面能使湾内的最高洪水水位下降约20%。  相似文献   
90.
辽东中部海岸地貌基本特征   总被引:2,自引:0,他引:2  
杨达源 《海洋科学》1992,16(4):49-51
根据地貌结构分析和晚更新世海侵沉积层的变位特征,认为辽东中部沿海地貌属缓慢的构造沉降海岸。  相似文献   
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