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51.
正海水吸收空气中的二氧化碳形成碳酸增加了海水的酸度,这种现象被称为海水酸化。据估测,到2100年,海水pH平均值将因此下降约0.3~0.4,至7.8~7.9[1]。海水pH值是海洋生态系统的关键因子,即使细微变化都将对海洋化学产生深刻影响[2],从而影响大多数海洋生物的生理、生化、代谢、生长、繁殖与生存,最终可能会导致海洋生态系统发生不可逆的变化,进而影响人类。海洋酸化  相似文献   
52.
海洋牧场运营模式的探讨   总被引:1,自引:0,他引:1  
为探讨在运营海洋牧场过程中如何实现持续良好收益,给相关经营企业带来利润和可持续发展,以烟台清泉海洋牧场为例作一探讨。根据经济社会发展变化将传统的水产养殖与海洋生态环境修复结合起来,将旅游、餐饮、蓝色体育、海洋食品、教育科普等相关产业进行融合发展的方式方法进行运营,实践结果证明能够收到好的收益效果。因此,海洋牧场除了发挥海洋生态修复这一利国利民的功能之外,将旅游、体育、食品、科普能多产业进行协调全面融合发展是实现经营海洋牧场相关企业进行长久可持续发展的关键所在。  相似文献   
53.
葛桐  林仕伟  曹阳 《安徽农业科学》2012,40(17):9419-9421
[目的]研究纳米二氧化钛对热带海洋细菌的广谱抑菌作用。[方法]在菌液中加入适量纳米TiO2,在UV固化灯照射下,每隔10min采集一次菌液,并进行培养和计数,研究其对热带海洋细菌的广谱抑菌作用。[结果]纳米TiO2在UV固化灯激发下具有很强的抑菌性,且最佳使用量为0.9 g/L。[结论]二氧化钛具有无毒、廉价、光谱抑菌的特点,是一种具有应用前景的新型材料。  相似文献   
54.
The feeding habits of juvenile coho salmon, Oncorhynchus kisutch, in the northern California Current were examined using samples from two different time periods (1980–85 and 1998–2003) of highly contrasting oceanographic conditions. The goal was to test the influence of interannual and interdecadal changes in taxonomic composition of prey, feeding intensity, and size spectra of teleost prey. Analyses were done for samples taken both early in the summer (June) shortly after the salmon enter the ocean, and also in late summer (September) following some ocean residency. Fish prey dominated coho salmon diets by weight during most years, but this trend was more pronounced during the 1980–85 sampling period. In terms of numerical composition, the diets were more variable on an interannual basis, but decapod larvae and euphausiids were important prey in most years. Pteropods and copepods were important prey during weak upwelling or El Niño years, whereas euphausiids were important during strong upwelling or otherwise highly productive years. Hyperiid amphipods comprised a substantial proportion of the diets only in 2000. Coho salmon showed highly significant differences in prey composition among years or between decades both in weight and numerical composition. The percentage of empty stomachs was highly variable by year in both June and September, but was significantly different only for September between decades. In contrast, an index of feeding intensity did not show many significant changes in either comparison. However, the relative size ratios for fish prey consumed were highly variable by year, and larger than average fish prey were consumed during 1998, leading to the highest feeding intensity observed.  相似文献   
55.
The pattern of temporal change in recruitment of steelhead trout ( Oncorhynchus mykiss ) entering the ocean between 1963 and 1990 was geographically coherent in all regions of British Columbia. A major increase in recruitment was evident for smolts entering the ocean after 1977. Subsequently, an out-of-phase response occurred after 1990, indicating that the effect of a possible 1990 regime shift had both temporal and geographical structure. Steelhead entering northern regions had increasing recruitment, while steelhead entering southern BC coastal regions had sharply decreasing recruitment. The evidence clearly indicates that the overall recruitment response since 1977 was primarily shaped by changes in marine (not freshwater) survival. Similar sudden changes in adult recruitment also appear to be occurring for other species of Pacific salmon in BC and Oregon, such as coho ( O. kisutch ), which appear to occur suddenly and show considerable persistence. A possible explanation for the change is that ocean productivity declined in coastal regions of southern BC after 1990, reducing the marine growth of juvenile salmon. The Bakun upwelling index shows a pattern of geographical coherence along the west coast of North America that could in principle explain the observed pattern of changes in recruitment. However, no evidence for a temporal shift in this index occurring around 1977 and 1990 is apparent. The reason for the sudden and persistent decline in ocean survival is therefore uncertain.  相似文献   
56.
海洋环境观测数据的质量直接影响海洋环境管理决策的科学性、准确性和可靠性,本文讨论了当前流行的一些质控方法,如相符性检验、合理性检验、相关性检验、分布拟合检验等在海洋环境观测数据质量控制中的应用,并在此理论基础上应用计算机程序实现海洋环境观测数据质量控制。  相似文献   
57.
网络环境下海洋高校图书馆信息资源建设探讨   总被引:2,自引:0,他引:2  
网络环境下,海洋高校图书馆的信息资源建设对海洋经济的发展有着重要意义,本文通过对海洋高校图书馆信息资源建设概况的调查,提出在信息资源建设中应注意处理的几种关系。  相似文献   
58.
中西太平洋金枪鱼围网渔业渔获组成及叉长与体重关系   总被引:1,自引:1,他引:1  
中西太平洋海区是世界金枪鱼围网作业的主要渔场之一[1]。目前从事生产的金枪鱼围网船约160艘[2]。据统计,2003年该海区的金枪鱼围网渔业总产量为117.28×104t,占其金枪鱼总产量的60%[3]。我国大陆地区金枪鱼围网渔业起步较晚,但发展较快,渔船已由2001年的1艘发展到2004年的8艘  相似文献   
59.
60.
  1. The protection of evolutionary processes and maintenance of genetic diversity is necessary for the persistence of biodiversity and ecosystem resilience. The importance of genetic diversity has been reflected in a range of marine policy mechanisms, and the genetic ‘toolbox’ has great potential to support marine protection and marine spatial planning (MSP) at multiple scales. Despite scientific advances in the application of genetics in marine protection and management, systematic integration of genetic information has been generally lacking, primarily due to a knowledge and communication disconnect between geneticists and the marine policy and management community.
  2. To meet these outstanding needs, a ‘geospatial genetics’ approach to spatially map species-specific genetic data and associated information in a way that can be readily integrated by practitioners into marine protection and MSP decisions was developed. Techniques to derive geospatial genetic data layers, which can be viewed and mapped alongside other kinds of spatial data commonly used by conservation practitioners, hold promise for increasing the accessibility of genetic data to support policy decisions more fully.
  3. While applicable to many mobile and sessile taxa, an initial focus was placed on marine mammals, and the approach was developed and refined through a series of international meetings and published papers, as well as the development of interactive, expert-reviewed case studies hosted on the MSP tool SeaSketch.
  4. Outcomes of the work to date are currently serving in the policy arena by informing the identification of Important Marine Mammal Areas, an initiative led by the IUCN Marine Mammal Protected Areas Task Force to apply criteria to identify marine mammal habitats across the world's ocean, seas and relevant inland waters through a standardized process.
  5. It has become clear that geospatial genetics has great potential to foster increased collaboration among an intersectional community of geneticists, spatial ecologists, and practitioners. This increased opportunity for dialogue and cooperation will help ensure that evolutionary processes are factored into marine protection and MSP processes, and potentially for freshwater and terrestrial systems.
  相似文献   
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