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多样性指数在海洋浮游植物研究中的应用   总被引:100,自引:12,他引:88       下载免费PDF全文
孙军  刘东艳 《海洋学报》2004,26(1):62-75
对海洋浮游植物群落分析中常用的多样性指数进行了比较研究,对物种丰富度依赖型、丰度依赖型和实测浮游植物群落中物种丰富度、Shannon指数(以2或e为底)、Pielou均匀度指数、Simpson指教(1-D或1/D形式)、Mangalef指数、Berger-Parker指数、McIntosh指数、McIntosh均匀度指数、Brillouin指数、Brillouin均匀度指数、Fishera指数和Q统计指数等不同多样性指数计算结果进行了比较,发现不同多样性指数对浮游植物群落多样性的分析存在明显差异.对于一般情况下浮游植物群落多样性的研究,物种丰富度、Matrgalef指数、Fisher α指数、Shannon指数、Simpson相遇指数和Pielou指数的综合使用是较合适的,但对Margalef指数和Fisher α指数的结果要谨慎解释,并在综合应用各指数的基础上提出了浮游植物群落多样性分析的一般步骤。  相似文献
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The international legal framework for marine spatial planning   总被引:1,自引:1,他引:1  
Frank Maes   《Marine Policy》2008,32(5):797
Increasing demand for ocean resources, both living and non-living, have already lead to loss of biodiversity, habitat depletion and irreversible damage to the marine environment. Furthermore, introduction of new kinds of sea uses, spatial extension of ongoing sea uses and the need to better protect and conserve the marine biological diversity will result in increasing conflicts among the various users, as well as between the users and the environment. Marine spatial planning as a process to allocate space for specific uses can help to avoid user conflicts, to improve the management of marine spatial claims, and to sustain an ecosystem-based management of ocean and seas. This article explores the rights and duties towards exploitation and protection of the marine environment under the jurisdiction of coastal states as reflected in two important global conventions, the United Nations Convention on the Law of the Sea and the Convention on Biological Diversity. Both Conventions provide the main legal framework for marine spatial planning that have to be taken into account in planning at the regional and national level.  相似文献
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乐清湾口海域春秋季甲壳动物的群落结构特征研究   总被引:1,自引:0,他引:1       下载免费PDF全文
根据2012年春季和10月在乐清湾口海域开展渔业资源调查所获甲壳动物资料,对乐清湾口海域的甲壳动物的种类组成、优势种、物种数量分布、生物多样性和群落结构相似性等群落结构特征及其影响因素进行了研究。结果表明,调查海域共鉴定出34种甲壳动物,隶属于2目17科23属,春季优势种仅有三疣梭子蟹1种,秋季为日本、口虾蛄、中华管鞭虾、三疣梭子蟹4种,两季优势种更替较显著;秋季物种数较春季丰富,调查水域中心区域物种数较多;秋季甲壳动物生物多样性指数高于春季;甲壳动物群落结构与海洋环境密切相关。乐清湾口海域的甲壳动物以季节性的广温低盐种类为主,该海域位于河口,受瓯江径流影响较大;春季受瓯江径流淡水水团影响,物种较少,而秋季受交汇水团影响,物种丰富;春秋季组内并无明显规律,地形、水深和水系等外部因素对甲壳动物群落结构影响较大。  相似文献
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Conventional sectoral management and piecemeal governance are considered less and less appropriate in pursuit of sustainable development. Ecosystem based marine spatial management (EB-MSM) is an approach that recognizes the full array of interactions within an ecosystem, including human uses, rather than considering single issues, species, or ecosystem services in isolation. Marine spatial planning and ocean zoning are emerging concepts that can support EB-MSM. EB-MSM is driven by high-level goals that managers aim to achieve through the implementation of measures. High-level goals and objectives need to be translated into more operational objectives before specific targets, limits and measures can be elaborated.Monitoring, evaluation and adaptation are necessary to ensure that marine management measures are both effective and efficient. Solid monitoring frameworks are the foundation of adaptive management, as they provide the necessary information to evaluate performance and the effectiveness of management actions. Marine protected areas (MPAs) - possibly set up in networks - constitute a key component in EB-MSM policies and practises and have been applied as a cornerstone in conservation of marine biodiversity, management of fish populations, development of coastal tourism, etc. Moreover, MPA experiences have provided methods and concepts (such as zoning) to a wider EB-MSM context. The assignment of values to biophysical features of the marine environment allows the direct assessment of related management choices and may assist EB-MSM.A range of monetary valuation techniques have been proposed to reduce attributes of goods and services to a single metric. However, in the marine environment such an approach is often over simplistic, and thus less reductive techniques may be necessary. Rather than producing a single metric, the results of non-monetary assessments guide policy allowing weight to be given as necessary to potential areas of conflict and consensus.Strategies to take into account climate change effects and geohazard risks in EB-MSM have been applied or proposed worldwide. EB-MSM regimes must be alert to such risks and flexible to account for changes.  相似文献
5.
The relative paucity and heterogeneous distribution of marine protected areas (MPAs) indicates the need for better understanding of factors that foster MPA establishment at local, sub-national, and national levels. The relationship between national-level MPA establishment and geographic, ecological, social, and political factors that may drive patterns and trends in MPA establishment were assessed. A country's coastline length is the strongest predictor of both the number and spatial extent of MPAs. Controlling for coastline, the Human Development Index (HDI) and spatial overlap with designated conservation priority areas are positively correlated with MPA establishment. Surprisingly, some factors influencing MPA establishment in case studies, such as percentage of fishers within a population, were not correlated with MPA establishment on a national scale. These national dynamics explain a relatively small proportion of variation, however, indicating that other biological or social factors, as well as sub-national processes, also influence MPA establishment. Positive and negative outliers illuminate the importance of policy engagement at both national and local levels. Ensuring a supportive enabling environment at the national or even multi-national level can enhance success at the local level.  相似文献
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