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291.
一个简单的二维线性模式用于考查近海海洋对过境热带风暴的动力响应过程中的底坡度和底摩擦效应。选择了自东向西和向西后转向的两个模式风暴路径。数值试验结果表明,海底坡度与风暴引起的水位波动、风暴中心后部的尾流以及路径右侧后方面的涡旋密切相关。而底摩察是阻尼风暴潮和风暴流持续增长的重要因子。结果还表明,近海对风暴的强响应偏向于风暴轨迹的右侧,这与Chang和Anthes(1978)对深海响应的研究结论是一  相似文献   
292.
近几年来,我们对山东近岸34个海岛和一些海湾进行了综合性调查,本文主要根据这些调查的实测资料.在综合分析整理的基础上.获得了山东近岸水域浮植物的现存量(叶绿素 a)为0.91mg/m~2,初级生产力水平为310.2mg/(m~2·d),基本接近温带海洋近岸水域标准;其分布特征是以莱州湾、渤海海峡、千里岩海区为最高,宫家岛、鸭岛海区为最低;季节变化显著,主要显示双峰型特征.根据初级生产力的测定结果,我们对山东近岸水域潜在的各级生物生产力做出了初步估算,旨在为山东近岸水域开展海水增养殖,合理开发海洋资源提供科学依据.  相似文献   
293.
This article reviews the development of two courses focussed on meeting Integrated Coastal Management capacity building needs: an undergraduate degree course, and a web-based distance learning course. Influential factors in the development of each course are identified and compared. Important considerations are found to be methods of quality assurance, course content, the temporal and spatial context of teaching and learning, level of learner empowerment, and the role of the teacher. It is concluded that in order to understand the role of such courses in capacity building, coastal educators need to share experiences and encourage reflection on the effectiveness of capacity building efforts.  相似文献   
294.
刘兴泉 《海洋与湖沼》1997,28(6):632-639
为了揭示沿岸海区冬季垂直环流及其温盐结构的分布特征和变化规律,利用三维斜压流体动力学模型,对具有岸界坡度变化、河流入海、海湾、岛屿和海槽的理想海区冬季的垂直环流及其温盐结构进行了数值模拟。其环流的数值结果表明,冬季沿岸海区的垂直环流普遍呈逆时针流动。在近表层为向岸流,沿岸为下降流,近表层以下为离岸流;近表层以下的离岸流在外海有明显的上升趋势;沿岸下降流自表层至底层逐渐由强变弱;就整个海区而言,随着自南往北海区水深的逐渐变浅和岸界地形坡度的由大变小,其沿岸下降流则由强变弱。  相似文献   
295.
An experimental investigation of coastal erosion generated by the action of regular and irregular waves was carried out in laboratory channels. Natural beach sand, with medium diameter of 0.35 mm and specific gravity of 2.63, was used in this study. A 1:5 initial beach slope was selected for the model tests. Different wave groups were generated over the initially flat beach, and the characteristics of coastal erosion geometry such as erosion lengths, erosion depths, location of maximum erosion point, and total erosion areas were measured. The most important parameters governing coastal erosion were evaluated by using earlier investigations and experimental results. These parameters were expressed as a dimensionless group by using π theory. The empirical relationships between the geometric characteristics of coastal erosion and the dimensionless group are proposed through regression analysis for pure regular waves, pure irregular waves, and regular-irregular waves. The parameters, which were used to define geometric characteristics of coastal erosion, were evaluated and some ratios of these parameters gave a constant value.  相似文献   
296.
The diversity of small-scale wetlands, high salinity tidal creeks, salt marshes, estuaries, and a wide and shallow shelf with the Gulf Stream close to the break makes the coastal zone of south-eastern North Carolina (U.S.) a natural laboratory for the study of the cycling of nitrogen (N) and phosphorus (P) in coastal and shelf waters. We assessed the summer concentrations, forms, and ratios for each N (total dissolved N, nitrate + nitrite, ammonium and dissolved organic N) and P (total dissolved P, o-phosphate and dissolved organic P) pool as these nutrients travel from tidal creeks, salt marshes and two large estuaries to Long and Onslow Bays. Additionally, we measured ancillary physical (temperature, salinity and turbidity) and chemical (dissolved oxygen, chlorophyll a and pH) water properties. Highest concentrations of all individual N and P compounds were found in the upper parts of each tributary and were attributed to loads from agricultural and urban sources to the coastal watersheds, continuing downstream to receiving estuaries. In all areas, dissolved organic N and P species were predominant constituents of the total dissolved N and P pools (64–97% and 56–93%, respectively). The lower parts of estuaries and surface shelf waters were characterized by oceanic surface values, indicating removal of N and P downstream in all tributaries. The different watershed and hydrological characteristics also determined the different speciation of N and P pools in each estuary. Despite a high level of anthropogenic pressure on the uppermost coastal waters, there is self-regulation in this coastal ecosystem with respect to human perturbations; i.e. significant amounts of the N and P load are retained within estuarine and nearshore waters without reaching the shelf.  相似文献   
297.
This article aims to analyze how private property regimes can co-exist with common property regimes in a coastal area. The case study shows how the dynamics of private property and common property right holders is in creating commitment to make symbiosis in resource use. This is based on a case study in two villages in West Lombok, Indonesia, where pearl-culture as a private property resource exists in a common property regime. This is a successful story in dealing with the tragedy of property rights in the country wherein established institutional arrangement is still absent. Nevertheless, this may be site specific, and fragile if there is no institutional arrangement combining formal and informal rules and involving both formal and informal authorities. To make a robust solution, multilevel solution must be considered: national, local, and community level, with reference to Japan case.  相似文献   
298.
Abstract. In 1997, Artegiani et al. depicted for the first time the seasonal climatology of the Adriatic Sea; they used the ATOS data set, formed by 5540 oceanographic stations sampled over this continental basin from 1911 to 1980. Lately, two Italian institutes working on the Adriatic Sea for long time, IBM and IRPEM, merged their recent data sets for the northernmost part of the basin. This yielded 3600 new oceanographic stations, concentrated in an area where 809 ATOS stations were located. The new data were quality checked, and then a seasonal climatology was drawn up as a first analysis step. The new climatology differed significantly from the ATOS results; this could be explained, at least partially, by the climatic changes that have occurred on this area. For example, air temperature increased significantly over northern Italy starting from 1988. Variations of the observed air temperature and Po River runoff qualitatively agree with sea surface temperature and salinity variations. A preliminary computation of heat fluxes based on ECMWF reanalysis confirms an increased heat flux to the Northern Adriatic Sea starting from 1988.  相似文献   
299.
风浪在开敞潮滩短期演变中的作用——以南汇东滩为例   总被引:11,自引:0,他引:11  
杨世伦 《海洋科学》1991,15(2):59-64
本文以引水船站风和波浪的相关性为理论依据,以南汇东滩滩面实测资料为基础,说明风浪是控制开敞潮滩短期演变的主要动力因子。  相似文献   
300.
山东省的海岸侵蚀灾害   总被引:1,自引:0,他引:1  
论述了山东省海岸侵蚀灾害的基本特征,详细叙述了9216号强热带气旋暴潮的海岸侵蚀灾害情况。分析了海岸侵蚀灾害的基本特征,即侵蚀灾害的普遍性,侵蚀原因的多样性,人为因素的突出性,侵蚀灾害的连续性和突发性灾害的严重性,最后提出了海岸侵蚀灾害的防治与对策。  相似文献   
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