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101.
2007年夏季和秋季,按照GB11607-1989《渔业水质标准》和GB3838-2002《地表水环境质量标准》,对陕西黄河湿地渔业水域环境质量的主要理化指标进行了现场监测,对渔业水域的主要水生植物进行了调查。结果表明:陕西黄河湿地渔业水域的池塘和大水面硫化氢(H2S)含量均符合标准,池塘和大水面的总磷(TP)及总氮(TN)均不符合标准。池塘和大水面渔业水域环境质量呈明显的富营养化现象,池塘比大水面富营养化现象严重,但湿地大水面的主要理化指标优于池塘,湿地大水面渔业水域生长的水生植物芦苇Phragmites australis和香蒲Typha orientalis对TP和TN具有一定的净化作用,通过监测分析提出了湿地渔业水域的保护措施。  相似文献   
102.
103.
在海洋渔业中 ,存在着自然状态的不确定性 ,这会引起人的行为的不确定性 ,进而引起资源供给的不确定性。不确定性使渔民对其行为的预期存在风险 ,因而他们总是试图规避风险以减少不确定性带来的损失。人们的风险规避行为可能带来海洋渔业资源过度使用的效应  相似文献   
104.
This interdisciplinary paper presents an empirical analysis of techno-institutional lock-in in a regional fishery, in the Logone floodplain in the Far North Region of Cameroon. In the Logone floodplain, one fishing technique is spreading exponentially even though it is changing the social, hydrological and ecological dynamics of the system in ways that are largely considered problematic by local communities. We use a complex systems framework to analyze large hydrological and socio-economic datasets. Results show how social-ecological feedbacks foster the spread of the technique and contribute to the process of lock-in. The lock-in leads to a resistance to change despite awareness of the technique’s impact, a situation that may also be described as a social-ecological trap. We identify and explain four kinds of positive feedback loops relating to socio-economic, behavioral, demographic and hydrological processes, respectively. We also identify possible solutions that consider the complexity of the feedback loops across multiple dimensions of the floodplain system.  相似文献   
105.
The Korean fisheries industry has long played a role as a national food industry with agriculture. Fisheries products supply about 39.2% of animal proteins that Korean people need. The industry, however, is facing great challenges including international arguments for reduction or abolition of fishery subsidies. Therefore, it is urgent for us to review the characteristics of fishery subsidies according to WTO, OECD, FAO and UNEP. This paper examines the status of Korean fishery industry, and to tackle the problems of the currently supported fishery policy funds, whose total amount in 1999 was more than 1 trillion Korean won with 77 fishery projects.  相似文献   
106.
Subsistence in coastal fisheries policy: What's in a word?   总被引:1,自引:2,他引:1  
Consideration of subsistence fishing activities seems particularly relevant to coastal fisheries policy, yet formal recognition of subsistence fishing is often absent from associated policy frameworks. A critical problem is the very meaning of the term “subsistence.” A review of the literature on subsistence, dominated until recently by North American research, reveals a schism between interpretations emphasizing material aspects of subsistence and interpretations highlighting cultural aspects. The North American literature on the subject is heavily influenced by a focus on Arctic indigenous populations emphasizing cultural survival. Ultimately, subsistence can be a matter of survival in the belly, the soul, or both. International case studies suggest that different interpretations of subsistence are appropriate in different circumstances, and that appropriate policy can be fashioned only after the local context of subsistence is understood.  相似文献   
107.
The phenomenon of discarding was studied using a multidisciplinary approach to allow the integration of biological, social and economic data. The research aimed to evaluate the strength of the case to reduce discarding in a single case study fishery, the English Nephrops fishery; to identify specific objectives for discard reduction; to identify factors that inhibit discard reduction and to determine the best means of achieving those objectives. Changes in trawl structure offered the best solution while having the least impact on fishing opportunities. However, the inadequate level of incentive was identified as the main impediment to discard reduction rather than the lack of technical ability. To implement effective measures to reduce discarding in this fishery, an increased level of incentive is required. Three measures are identified as a means to achieve this.  相似文献   
108.
The Magnuson-Stevens Fishery Conservation and Management Act (1976), opened a new era of federal fishery management in the United States. It was enacted primarily to establish a system for conserving and managing fisheries in the new 200-mile (EEZ). The US assumed exclusive authority for managing all fisheries within the EEZ, except for highly migratory species such as tunas and billfishes. Within the framework of the Act, eight Regional Fishery Management Councils (Regional Councils) were created, which are responsible for preparing Fisheries Management Plans (FMPs) in federal waters under their jurisdiction. Each FMP must meet a series of National Standards (NSs) for conservation and management. The Act was reauthorized in 1996 with the passage of the Sustainable Fisheries Act (SFA), which aimed at fine tuning the fishery regulatory apparatus that was established under the original Act. This "fine tuning" involved increased attention to biological concerns, and removal of ambiguities within it. The Act was reauthorized again in 2007, mainly to provide for more clear directives and regulations to end overfishing. After more than thirty years since the Act was passed into law, the debate among conservationists, commercial and recreational fishery representatives, and politicians on the effectiveness of the Act in achieving its purported goals it still continues. Is the Act delivering on its promises? Do NSs reflect the most important priorities for the US fishery resources, conservation and sustainable exploitation? Do the Regional Councils represent all parties that should be involved in the fisheries resources management? The aim of this paper is to provide a critical analysis to answer these questions. This paper begins with a review of the Act and its background, followed by discussion and analysis of the Act's benefits and flaws. Finally, suggestions for the implementation of its structure and future directions in fishery management strategies are made.  相似文献   
109.
This paper uses a quarterly, game-theoretic model of the Northeast Atlantic mackerel to study the fishing strategies of five players: the EU, Norway, the Faeroe Islands, Iceland, and the international fishery on the high seas. Data on the spatial distribution of fish catches (1977–2011) are used to model changes in the distribution of the mackerel stock. The Nash equilibrium solutions predict a severe decimation of the stock through overfishing, either by parties (Iceland, the Faeroe Islands) that refuse to cooperate or by a general absence of cooperation. There is a wide discrepancy between this prediction and reality, as the stock seems, at most, only moderately overexploited, despite non-cooperation by Iceland and the Faeroe Islands. It is conjectured that these parties, and others, may engage in a degree of quasi-cooperation that falls somewhat short of full cooperation but avoids the extreme destruction of the Nash equilibrium. This tacit cooperation can be seen as being maintained by a mutually assured destruction of the fisheries of all parties in case they go to the logical extremes of non-cooperation.  相似文献   
110.
随着渔业资源的衰退,为保护渔业资源,我国制定出台了多项渔业资源管理政策,但实际应用中出现了诸多问题,导致政策未完全实现预期效果。为提高我国渔业资源管理政策成效,促进我国渔业经济高质量发展,文章利用案例分析法、定性分析与定量分析结合的方法,从投入控制、技术控制和产出控制角度,梳理我国三类渔业资源管理政策,系统分析我国各类渔业资源管理政策演进与应用及应用过程中存在的问题,有针对性地提出我国渔业资源管理政策优化方案。研究发现,我国渔业资源管理政策存在政府监管成本过高、政策执行不到位、渔业从业人员保护渔业资源的责任不清晰、渔业从业人员转业困难以及立法不完善的问题。未来可从发展渔业合作组织、增强渔业从业人员渔业资源保护意识、明确渔业从业人员保护渔业资源的具体责任、组织渔业从业人员职业培训和完善渔业资源管理政策立法方面着手,改进渔业资源管理政策。  相似文献   
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