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991.
《联合国海洋法公约》生效对公海渔业的影响   总被引:1,自引:0,他引:1  
在归纳世界大多数沿海国家执行联合国海洋法公约,主要实施公海制度的实践,以及分析公约有关条款的基础上,指出今后渔业管理制度将朝着有利于沿海国的方向发展,远洋渔业国只有与沿海国密切合作,承担公约所规定的养护生物资源的义务,才能确保远洋渔业生产的持续稳定发展。根据我国渔业的实际状况,分析了海洋法公约生效对我国公海渔业生产产生的一些不利影响,并提出对海洋渔业发展的一些看法  相似文献   
992.
Individual performance defines population dynamics. Condition index – a ratio of weight and some function of length – has been louded as an indicator of individual performance and recommended as a tool in fisheries management and conservation. However, insufficient understanding of the correlation between individual-level processes and population-level responses hinders its adoption. To this end, we use composite modelling to link individual's condition, expressed through the condition index, to population-level status. We start by modelling ontogeny of European pilchard (Sardina pilchardus, Clupeidae) as a function of food and constant temperature using Dynamic Energy Budget theory. We then provide a framework to simultaneously track the individual- and population-level statistics by incorporating the dynamic energy budget model into an individual-based model. Lastly, we explore the effects of fishing pressure on the statistics in two constant and food-limited environmental carrying capacity scenarios. Results show that, regardless of the species' environmental carrying capacity, individual condition index will increase with fishing mortality, that is, with reduction of stock size. Same patterns are observed for gilthead seabream (Sparus aurata, Sparidae), a significantly different species. Condition index can, therefore, in food-limited populations, be used to (i) estimate population size relative to carrying capacity and (ii) distinguish overfished from underfished populations. Our findings promote a practical way to operationally incorporate the condition index into fisheries management and marine conservation, thus providing additional use for the commonly collected biometric data. Some real-world applications, however, may require additional research to account for other variables such as fluctuating environmental conditions and individual variability.  相似文献   
993.
南北极渔业管理机制的对比研究   总被引:1,自引:1,他引:1  
邹磊磊  黄硕琳  付玉 《水产学报》2014,38(9):1611-1617
极地权益成为新兴的国际关注热点,而开展极地渔业活动并参与极地渔业管理机制构建是实现极地海域"实质性存在"及权益的重要切入点。本文采用对比研究的方法,从渔业管理协议、渔业管理组织、渔业管理理念、与其他国际协议及组织的互动性、以及渔业管理职责等方面分析南北极渔业管理机制中的各项举措,并剖析各自管理举措中的亮点与瓶颈,且以此进一步讨论南北极渔业管理机制的相互借鉴作用。对比研究为南北极渔业管理实践经验提供了交流的平台,同时有助于深刻解析南北渔业管理机制的特色,从而为制定中国极地渔业政策提供相应的背景资料。  相似文献   
994.
Scientists feel discomfort when they are asked to create certainty, where none exists, for use as an alibi in policy‐making. Recently, the scientific literature has drawn attention to some pitfalls of simulation‐based fisheries management‐strategy evaluation (MSE). For example, while estimates concerning central tendencies of distributions of simulation outcomes are usually fairly robust because they are conditioned on ample data, estimates concerning the tails of distributions (such as the probability of falling below a critical biomass) are usually conditional on few data and thus often rely on assumptions that have no strong knowledge base. The clients of scientific advice, such as the European Commission, are embracing the mechanization of the evaluation of proposed Harvest Control Rules against the precautionary principle and management objectives. Where the fisheries management institutions aim for simple answers from the scientists, giving ‘green/red light’ to a proposed management strategy, the scientists are forced into a split position between satisfying the demands of their advisory role and living up to the standards of scientific rigour. We argue against the mechanization of scientific advice that aims to incorporate all relevant processes into one big model algorithm that, after construction, can be run without circumspection. We rather encourage that fisheries advice should be a dynamic process of expert judgement, incorporating separate parallel concurrent, lines of scientific evidence, from quantitative and qualitative modelling exercises and factual knowledge of the biology and the fishery dynamics. This process can be formalized to a certain degree and can easily accommodate stakeholder viewpoints.  相似文献   
995.
黄海太平洋褶柔鱼种群动态的研究   总被引:1,自引:0,他引:1  
根据近年来我国主要海洋渔业公司和群众渔业单位,在黄海拖网生产专捕和兼捕太平洋褶柔鱼的统计资料,结合多年来渔业生产经验,对鱿鱼的洄游分布状况作了具体分析。同时根据2004-2006年5次对山东近海渔业资料调查中的渔获统计及生物学测定,研究近年来黄海鱿鱼资源变动规律,并利用扫海面积法估算整个黄海海域的资源量。结果表明目前黄海鱿鱼资源利用较充分,并提出资源开发保护建议。  相似文献   
996.
Data collected through a stratified catch and effort survey were used to assess the impact of the 1998 mass coral bleaching event on socio-economic and biological indicators for the coastal reef fisheries of the Seychelles. There was a significant reduction in the abundance index and monthly yields per square kilometre for representatives of the family Siganidae following 1998. However, this was not associated with the bleaching event and conformed with the declining trend prior to the impact. Abundance indices and yields per square kilometre did not change significantly for the primary target families of the handline fisheries (Lutjanidae, Serranidae, Lethrinidae and Carangidae). Declining trends in abundance indices and yields for Octopodidae reversed after 1998, although the phenomena could not be independently linked to coral bleaching. Whilst critical resource based management issues are identified for the demersal handline fishery, the results suggest that there were no negative short-term bio-economic impacts on Seychelles coastal reef fisheries associated with mass coral mortality.  相似文献   
997.
Fisheries-Oceanography Coordinated Investigations (FOCI) is a National Oceanic and Atmospheric Administration (NOAA) research programme seeking to understand recruitment processes of commercially exploited Alaskan fishes. The FOCI is mainly comprised of scientists at the Pacific Marine Environmental Laboratory and the Alaska Fisheries Science Center who study both the biotic and abiotic environment, including processes within larval patches through integrated field, laboratory, and modelling studies. The initial focus of studies was walleye pollock ( Theragra chakogramma ) spawning in Shelikof Strait, Gulf of Alaska. The choice of this population for our research was based on development of a large fishery and the substantial variation in recruitment that was observed in the late 1970s and early 1980s. Also, the early life history of this population is quite predictable and restricted both temporally and spatially. Walleye pollock spawn consistently in a small part of Shelikof Strait in early spring from which a large patch of eggs and later larvae is produced. In most years this concentration of larvae drifts to the south-west through the strait during April and May. Large numbers of larvae are often found in eddies which frequent the area and we have observed improved feeding conditions for larvae, in as opposed to out of eddies. We have found that first-feeding larvae have higher survival rates during calm periods, rather than in storms, and that in many years recruitment is largely set by the end of the larval period, although in some years age-0 juvenile mortality is also important. FOCI now generates information that is being used for management of this resource.  相似文献   
998.
在对绿色水产品与无公害水产品进行辨析的基础上,从我国水产业发展过程中面临的问题出发,论述了发展绿色水产品的目的和意义,并对阻碍我国绿色水产品发展的问题进行了初探,进而提出了一些建议和对策。  相似文献   
999.
1000.
This paper evaluates the implications of managing fisheries to achieve a BMEY target, or a biomass level that maximizes net economic returns in the fishery, and discusses the role of private ownership and the trade‐offs between economic and conservation benefits in this setting. The paper shows how a BMEY target can be used to: (i) determine relative employment and profitability measures; (ii) account for both the harvesting and processing sectors; and (iii) incorporate the interests of consumers and producers of fish. The profits–employment trade‐off of adopting a BMEY target vs. a traditional BMSY target is calculated using a model and data from the Western and Central Pacific tuna fisheries (WCPTF), while a generic bioeconomic model is constructed to show numerical values of BMEY from including processing and/or retail sectors and the consumer benefits of harvesting fish. For the WCPTF, results show that the long‐term gains per job lost from pursuing a BMEY target are worth several times the value of the average GDP per capita of Pacific Island Countries. The generic bioeconomic model shows that including a processing and/or retail sector, as well as measures of consumer benefit, lowers the BMEY target. However, there remains a broad range of parameter values for which BMEY is still greater than biomass at maximum sustainable yield, or BMSY. The paper also illustrates cases where BMEY > BMSY at different values of the price elasticity of demand, margins for processing and/or retail sectors and values of the discount rate.  相似文献   
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