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1.
Marine‐protected areas (MPAs) are an effective means of improving habitat quality and biodiversity in the world’s oceans. While the advantages of MPAs as a mechanism for conservation and biodiversity are well established, the potential improvements to fishery performance resulting from a network of MPAs are still being established. Countries around the world have committed to establishing networks of MPAs within their waters by 2020, in response to the United Nations Convention on Biological Diversity. This, coupled with the increasing global demand for seafood and heavy reliance on fishery resources as a source of economic development for many coastal communities, means that an understanding of how these networks can be expected to impact fishery performance is extremely important. We use a difference‐in‐difference modelling approach to isolate the change in the fishery performance associated with the south‐east marine reserve network in Australia. We find no evidence that the economic performance of adjacent fisheries was negatively impacted by the network. This lack of impact is likely due to a network design explicitly intended to avoid effort displacement in key fisheries, along with fishery management changes intended to remove excess fishing capacity.  相似文献   
2.
No‐take marine reserves have been increasingly advocated as an effective means of supporting marine ecosystems and conserving fisheries resources. A major problem that can hinder the effectiveness of no‐take reserves is the incidence of illegal fishing, which has created significant ecological and economic losses in global fisheries. We construct a bioeconomic model to explore the connection between the effects of no‐take reserves and illegal fishing activities in relation to the level of regulatory control of illegal activities in the reserve and fished areas. Our parameterised model shows that the effects of no‐take reserves on both the extent of illegal fishing and the fish biomass critically depend on illegal fishing regulations and the scale and patterns of fish dispersal. In a fishery where illegal fishing can only be partially controlled, increasing the size of the no‐take reserve may result in a lose‐lose situation in which the level of illegal fishing effort increases and the total biomass decreases. Our results further show that when the pattern of fish dispersal is density dependent, imposing a stricter control on illegal fishing in either reserves or fished areas increases the aggregate level of illegal fishing.  相似文献   
3.
海洋经济被视为引领世界经济发展的新引擎.基于结构方程模型在经济学领域分析复杂关联因素中的优势,采用偏最小二乘结构方程模型研究海洋科技创新能力、蓝色经济发展和区域经济发展之间的关联效应,分析海洋科技与经济发展之间的内在作用机理.实证研究表明:海洋科技创新能力对蓝色经济发展具有显著的直接促进作用;引入蓝色经济作为中介变量形成传导路径,科技创新能力对驱动区域经济发展具有间接效应及明显的总体作用.  相似文献   
4.
论文以海域使用金评估为研究对象,在分析海域使用金与海域使用权关系的基础上,论述了海域使用权价格体系由,迚而探讨了海域使用权价格评估的方法。在此基础上,阐释了海域使用金评估应分为基本不改变海域自然属性用海类型、一定程度上可能会改变海域自然属性用海类型及一次性基本完全改变海域自然属性用海类型三种情况设定基本思路,以期丰富我国海域使用金评估的理论与方法,为今后海域使用金评估研究提供借鉴参考。  相似文献   
5.
海洋文化产业是文化产业中特殊的组成部分,是当代文化产业的一个前沿研究领域。本文运用理论研究和实地调查相结合的方法,列举舟山群岛鲁家峙、岱山东沙镇、普陀山、朱家尖、沈家门、长峙岛、蚂蚁岛、太阳谷、朱家尖白山、桃花岛等实际案例,从文化产业集群三大核心定律出发,即产业链组合与延伸的规律、区位优势与选择的规律、产业集聚与联动的规律,充分揭示了舟山群岛海洋文化产业集群的内在规律及发展思路,提出舟山应结合各个岛屿的资源禀赋特征,因岛制宜构建不同种类的海洋文化产业集聚区的建议,对于舟山群岛海洋文化产业集群发展具有一定的指导意义。  相似文献   
6.
论文主要分析了页岩的地质情况,结合其特征,分析气储层的特殊性。论文通过总结当前存在的问题,分析与总结经验,探究页岩气储层录井技术的要点。论文提出页岩气储层的岩石内硅质成分占比较高,且钙含量也比较高,岩石既坚硬又脆弱,在钻井阶段,要使钻井速度保持在较高水平。通过合理使用综合气相色谱仪,可发现油气开发过程中存在的问题,其应用优势比较明显。  相似文献   
7.
Estuaries provide advantageous sites for both harbors and fish habitats. In many countries, harbor expansion in estuaries contributed to the decline of fish populations with impacts at the global scale. Restoring these habitats is important to prevent a global biodiversity crisis but is costly and potentially unaffordable for polluters under the Polluter Pays Principle. Such affordability issues prompt decision-makers to reduce environmental targets of restoration programs. Harbor infrastructures destroy fish habitats but generate benefits for society and contribute to the public interest, raising some questions on who is responsible for environmental degradations and who can afford environmental restoration costs? One way to allocate restoration costs is to analyze the amount of harbor services consumed by economic sectors. This paper addresses these questions by computing burden sharing scenarios with an input–output matrix. These scenarios are simulated under the shared responsibility principle to distribute restoration costs among stakeholders in the Seine estuary, France.  相似文献   
8.
We have examined perceived barriers to the export of Icelandic marine products and how they have changed over a period of nearly 20 years. We used qualitative and quantitative information from two different surveys conducted in 1993 and 2011. We identified nine main barriers to export that existed in both 1993 and 2011, plus an additional seven factors that prevailed only in 1993 or only in 2011. Further, we distinguished whether these factors were internal or external to the decision area of the Icelandic export firms. This report details the outcome of each survey, compares them quantitatively, and explains the patterns observed using the survey interviews of exporters.  相似文献   
9.
本文利用方向性距离函数与 Malmquist-Luenberger (ML)指数,构建了海洋经济绿色全要素生产率测度及技术进步要素偏向判别模型。以 2006-2016年海洋经济投入产出相关数据为基础,系统地分析了不同时期我国海洋经济绿色增长的差异。研究显示:第一,从全国来看,我国海洋经济绿色全要素生产率呈现上升趋势。然而在资源环境约束下,海洋经济绿色全要素生产率的增长率呈现出先降后升的趋势。第二, 从地区视角分析,技术进步是11个沿海地区海洋经济绿色生产率增长的主要驱动因素,且技术规模的变化影响最为显著。第三,就技术进步的偏向性角度而言,海洋经济整体上呈现出海洋劳动与资源的依赖性特征,但是大部分沿海地区的海洋经济呈现出节约资本,使用劳动和资源的特征,证明我国节能环保政策初显成效。  相似文献   
10.
目前应用于油气田的示踪剂为水溶性示踪剂或者是气体示踪剂.经过多年的研究,开发了一种新类型的微颗粒固体示踪剂,并在长庆油田致密油藏中成功施工,标志着从实验成功走向了矿场.固体示踪剂在油气田开发中的应用前景广阔,尤其对致密油藏井间裂缝开度的定量描述具有指导意义.  相似文献   
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