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1.
海洋渔业生产安全,关系到广大渔民的切身利益,一直是各级政府部门高度关注的民生问题.建设好海洋渔业安全环境保障系统,为渔业生产安全管理提供有力的技术支撑,不仅是国家海洋局当前重中之重的工作,也是沿海各省自身应做好的工作职责.而通过渔港有效避风面积计算确定渔港避风容量,确保渔船在港内安全避风,是海洋环境专题预报中的重要内容.本文利用Mike21-BW模型,结合霞关一级渔港的设计实例,计算渔港的港内波况,统计出渔港有效避风面积,并按0.6 m以下、0.6-0.8 m和0.8-1.0 m三类港内波高段进行划分,确定相应的避风区域,进一步完善海洋渔业生产安全保障系统,为海洋渔业行政主管部门指导渔业安全生产提供了有力的技术支撑.  相似文献   

2.
象山港避风锚地工程潮流泥沙模型试验研究   总被引:2,自引:1,他引:1       下载免费PDF全文
在分析现场实测资料的基础上,借助象山港整体变态物理模型,通过潮汐水流定床和悬沙淤积试验,对湾内拟建奉化市避风锚地工程实施后,附近海域的潮流场变化和海床淤积情况进行了系统研究。研究结果表明,避风锚地工程对航道、渔港等周边重要设施的影响有限。从而为工程的海洋环评、海域使用论证及工程设计提供了技术支撑,也为半封闭港湾内其它类似涉海工程的可行性论证提供了可借鉴的经验。  相似文献   

3.
本文介绍了海上极值波高设计值的确定方法,在数学原理上,该方法主要是通过波高的理论分布,或者由实测资料得出的波高经验概率分布,推求海上极值波高的众值和具有一定保证率的设计值。对于实测波高经验分布的模拟,本文采用F(x)=1-exp[-αx~bexp(-cx~d)]形式的拟合函数,并用非线性最小二乘法原理确定拟合函数中的非线性参数。实践证明,本方法计算简便,效果良好,可供实际工程设计时使用。  相似文献   

4.
针对当前高密度多波束水深数据抽稀后所构建数字水深模型(digital depth model,DDM)的航海安全性缺少估计这一问题,分别以最浅点法、最近点法和平均值法3种常用方法抽稀水深数据并构建DDM,在此基础上,分析不同抽稀方法所构建DDM随尺度变化的深度保证率变化规律,采用统计分析的方法建立DDM深度保证率与抽稀尺度、海底地形复杂因子之间的数学回归模型。实验表明:该回归模型不仅可用于估算基于不同抽稀方法所构建DDM的深度保证率,也为确定满足适合的DDM深度保证率所需要的抽稀尺度提供了理论依据。  相似文献   

5.
强潮河口建港水域条件分析方法的探讨   总被引:1,自引:0,他引:1  
回顾了以往港口码头水域位置的选择方法,对潮汐河口潮位和地形冲淤变化频繁的水域,初步探讨了港口选址方法,提出了典型潮保证率、低水位水深保证率、中水位水深保证率、典型年水深历时保证率等分析统计方法,并用码头计算实例分别加以说明,这对强潮河口中小型码头的选址有参考意义.  相似文献   

6.
在概率分布线型确定下,水文频率计算就是根据样本资料估算其中包含的参数。计算P-Ⅲ型分布参数的方法很多,目前常采用的最简单的方法是三点法,用图解适线求参数。本文中笔者建议用二点法直接利用K值表求参数。该方法简便,且不易出错。同时又能保证适线法的精度要求。  相似文献   

7.
海底地形不易进行实地探测及核实,海底地形格网数据产品精度指标的确定不具备实地核实的条件,为了确定海底地形格网数据精度指标,通过大量的数据实验,分析得出单位面积内,一定比例的极值水深差值的平均值与海底地形之间有一定的线性关系,从而提出了通过单位面积水深插值来划分海底地形的一种量化方式,并依据实验数据,分析误差规律,给出了海底地形格网数据中误差的精度指标及方法。  相似文献   

8.
文章通过对历史上影响苍南近岸海域的24场风暴潮过程进行分析筛选,确定1323“菲特”为最危险台风路径基础,设计了8~17级的间距为22.5 km的18条构造台风路径,采用FVCOM浪、潮、流耦合模式分别计算潮位场、流场和浪场分布,通过分析渔港岸线是否淹没、锚泊地是否船只走锚、防波堤防浪能力3个指标确定单项防台评估能力,按“就低不就高”的原则最终确定霞关一级渔港的防台风等级为9级,并且渔船锚泊是渔港的薄弱环节,最后结合研究过程中发现的问题,提出渔港防台风建议。  相似文献   

9.
近年来,军队和地方港口建设中,在一些水深达20 m的水域,选择了造价相对较高、但安全性和耐久性较好的斜坡式结构防波堤。但在确定护面块体稳定重量时却发现,按照相关规范计算的重量值偏小,不能满足安全性的要求。结合某船厂防波堤的断面物模试验,对大水深的斜坡堤护面块体的稳定性进行了初步分析,发现在该试验中块体的临界重量为8.15 t。并提出在计算块体稳定重量时应考虑水深的影响,适当降低块体稳定系数的取值。  相似文献   

10.
为合理确定锚地布置,根据锚地抗风浪要求,采用综合考虑波浪折射、绕射、反射联合计算的港域不规则波数学模型进行爵溪防波堤锚地的波浪传播变形计算,提出锚地防波堤最为合理平面布置方案,满足了当地渔业生产泊锚安全。  相似文献   

11.
12.
<正>我国是海洋大国,海岛众多。海岛是壮大海洋经济、拓展发展空间的重要依托,是保护海洋环境、维护生态平衡的重要平台,是捍卫国家权益、保障国防安全的战略前沿。2009年12月26  相似文献   

13.
The New Zealand Waters Pollution Regulations 1963, referring to recreational water to which the public can gain access, states that the “coliform bacteria content shall not consistently exceed 1,000/100 ml”. This standard is now under revision, and the suggested new standard is a median faecal coliform index of 200/100 ml with a maximum value not exceeding 400/100 ml.

Recent literature supports the use of faecal coliform sub‐group bacteria as the best indicator of faecal pollution and reference is made to the membership of this sub‐group. Inherent inaccuracies of the Most Probable Number (MPN) method of assessing bacterial populations are pointed out, such as experimental variations with different cultural media, and possible errors in interpretation of results. In North America, there is evidence that an MPN for the total coliform group of 1000/100 ml indicates a faecal coliform sub‐group MPN of 200/100 ml, and epidemiological experience supports these values as standards.

We tabulate and discuss evidence that the usual ratio of faecal coliforms : coliform group bacteria is typically 1 : 1 in fresh and marine waters of the Wellington region, and that a more attainable standard would be 500 faecal coliforms/100 ml. In ratios quoted in this paper, ‘coliform group’ means the remainder of the coliform group excluding faecal coliforms. The World Health Organisation (1963) definition, of the entire group of coliforms, is not intended. The ratio is different in other parts of New Zealand; in Auckland, for example, the ratio is close to that found in the United States.  相似文献   

14.
《Coastal Engineering》1999,36(3):263-269
Using the logarithmic wind profile and typical values of dimensionless sea roughness for different sea states, simple power expressions are derived for the wind profile over water. The power expressions are useful for correcting measured wind speed data at a given elevation (up to an elevation of 60 m) to the standard elevation of 10 m commonly used in coastal engineering studies. The analysis shows that the 1/7 power expression (suggested in [U.S. Army Corps of Engineers, 1984. Shore Protection Manual, Vol. 1. Coastal Engineering Research Center, Vicksburg, USA.] and commonly used today) is a good approximation (<3% error) of the logarithmic profile for various sea states up to an elevation of 20 m. Above this elevation, the 1/7 power expression underestimates the wind speed for moderate to fully developed sea states.  相似文献   

15.
This paper systematically reviews and synthesizes peer-reviewed, English-language scientific publications (n=212) to identify relevant research about how Ecosystem-Based Adaptation (EBA) is integrated with coastal planning. Preferred Reporting Items for Systematic reviews and Meta-Analysis (PRISMA) methodology is applied in this study. Attention was given to studies concerning human-environment interactions as opposed to physical or biological climate change issues alone because the coastal planning and EBA approach addresses the management of human actions in nature. The literature references include the issue of climate change (77%); however, limited evidence of EBA in coastal areas are reported (18%), and it is evident that the issues have become relevant in the scientific literature published in recent years. Broad texts demonstrate that SLR is one of the major long-term impacts (68%), and all of these papers recognize the most affected ecosystems in the tropics would be mangroves. EBA is an emerging option that can offset anticipated ecosystem losses and improve coastal planning to cope with SLR because it provides benefits beyond climate change stressors. There is a need to synthesize a road map for incorporation of mangrove regulations into local planning instruments and for building capacity for their implementation. Application of PRISMA in marine science will enhance future reviews, facilitate the systematic search and adequately document any theme, and also be useful in determining research gaps or information needs.  相似文献   

16.
田其云 《海洋科学》2011,35(4):89-93
采用交叉学科分析的方法尝试对生态学与法学进行分析,探讨海洋渔业资源恢复法律制度的生态学基础.认为,在海洋渔业资源恢复法律制度设计中遵循生态规律、选择过程导向的恢复模式能提高制度的科学性,有利于制度的操作和实施.进一步分析了许可证管理对海洋渔业资源的公平分配,技术法律规范对渔业资源恢复过程进行的生态控制,争端解决机制对海...  相似文献   

17.
Marine conservation actions are promoted to conserve natural values and support human wellbeing. Yet the quality of governance processes and the social consequences of some marine conservation initiatives have been the subject of critique and even human rights complaints. These types of governance and social issues may jeopardize the legitimacy of, support for and long-term effectiveness of marine conservation. Thus, we argue that a clearly articulated and comprehensive set of social standards - a code of conduct - is needed to guide marine conservation. In this paper, we draw on the results of an expert meeting and scoping review to present key principles that might be taken into account in a code of conduct, to propose a draft set of foundational elements for inclusion in a code of conduct, to discuss the benefits and challenges of such a document, and to propose next steps to develop and facilitate the uptake of a broadly applicable code of conduct within the marine conservation community. The objectives of developing such a code of conduct are to promote fair conservation governance and decision-making, socially just conservation actions and outcomes, and accountable conservation practitioners and organizations. The uptake and implementation of a code of conduct would enable marine conservation to be both socially acceptable and ecologically effective, thereby contributing to a truly sustainable ocean.  相似文献   

18.
This paper summarises research and options for sustainable sea transport in Oceania with a focus on domestic shipping. This debate is situated initially within the context of the current Pacific domestic shipping scenario, a region of minute economies connected by some of the longest sea transport routes in the world. All current options are fossil fuel powered and increasingly uneconomic and unsustainable. Many routes are marginal or unviable and a vicious cycle of old ships replaced with old ships prevails. Although a central and essential issue of many Pacific communities, the option of pursuing sustainable sea transport is currently invisible within the policy space at all levels. Various renewable energy options are possible and increasingly available. Recent research finds that these have strong potential for providing benefits across multiple wellbeings. The barriers to pursing this agenda are complex and poorly understood but are perceptual and institutional more than technological. A small number of critical experiments during the last oil crisis provide critical lessons and direction.  相似文献   

19.
20.
正Aims and Scope Being an international journal, China Ocean Engineering (COE) takes its prime function as the integration of new research concepts, equipment, technology, materials and structures and other scientific advances within the field of estuarial, coastal,offshore, and deepwater engineering with particular reference to developments. The Journal is concerned with all engineering aspects involved in the exploration and utilization of ocean resources. Topics regularly covered include research, design and construction of structures (including wharfs, dikes, breakwaters,platforms,mooring systems,etc.),instrumentation/testing (physical model and numerical model), wave dynamics, sedimentation,structural/stress analysis, soil mechanics, and material research.  相似文献   

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