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101.
There have been few rigorous assessments of the effectiveness of participatory processes for natural resource management. In Bangladesh an approach known as Participatory Action Plan Development (PAPD) has been developed and applied. By combining problem identification and solution analysis by separate stakeholder groups with plenary sessions it is claimed to result in consensus and more effective community based management. Methodological issues in assessing the effectiveness of such development are discussed and good practice illustrated. Under the same project there were sites where PAPD had been used and others without its use so a comparative assessment could be made. However, for an appropriate assessment it is important to identify clear testable hypotheses regarding the expected benefits, appropriate measures, and other factors which may affect or confound the outcome. The paper illustrates how participatory assessment involving both individual opinions and focus groups can be systematically recorded, quantified and used with other data in statistical analysis. By using statistical modelling methods at an appropriate level of aggregation and controlling for other factors, benefits from PAPD were found to be significant. The systematic approaches and practices recommended from this example can be applied in similar situations to test the effectiveness of participatory processes using participatory assessments.  相似文献   
102.
Hector’s dolphin Cephalorhynchus hectori is found only in New Zealand waters. We carried out a population survey of the North Island subspecies Cephalorhychus hectori maui, also known as Maui’s dolphin. The total population size estimate is 111 individuals (95% confidence interval = 48-252). The small population size confirms its critically endangered IUCN status. A sustainable level of human-caused mortality for this population would be 0.16 (one dolphin every 6.4 years). This essentially means that fisheries bycatch, and where possible other human impacts, need to be eliminated to allow population recovery. A protected area has been created to reduce the threat from entanglement in fishing gear. Gillnet fishing is prohibited along a 210 nautical mile stretch of coastline. The main concerns are that gillnet fishing is still allowed inside harbours and trawling continues inside the protected area.  相似文献   
103.
As large, long-lived seabirds with delayed and slow reproduction, albatrosses have low intrinsic mortality rates and are especially vulnerable to extinction from extrinsic sources of mortality such as fishery bycatch. Leg-band recovery information for waved albatrosses revealed mortality from both incidental catch and intentional catch for human consumption. Annual adult survival in 1999-2005, estimated from capture-mark-recapture data, was lower than historical estimates. This recent increase in adult mortality probably contributed to recent and dramatic shrinkage of the breeding population; periodic matrix models confirm that population growth rate is most sensitive to changes in adult survival. Banding data and recovery information also suggest that capture by fisheries is male-biased, which should reduce fecundity in this species with obligate bi-parental care. This new documentation of bycatch, harvesting, and associated demographic consequences provides reason for serious concern about the persistence of the single breeding population of the waved albatross.  相似文献   
104.
依据2004~2010年对广西合浦廉州湾增养殖区水质连续调查监测结果,选择高锰酸盐指数(CODMn)、无机氮(DIN)、活性磷酸盐(DIP)3个代表性指标作为评价因子,采用Danniel趋势检验的Spearman秩相关系数法对该增养殖区水质状况变化趋势进行研究分析。结果表明,合浦廉州湾增养殖区水质CODMn、DIP含量保持较平稳状态,而DIN含量则呈上升趋势。削减、控制外源性氮源施入仍然是今后环境治理工作的主要任务。  相似文献   
105.
Pre-spawning adult samples of long tailed hake, Macruronus magellanicus, were obtained from fisheries vessels in one location in the southeast Pacific Ocean and three in the southwest Atlantic Ocean, at different latitudes. Population structure was determined based on six nuclear hypervariable microsatellite loci and on mitochondrial DNA sequence variation at the locus COI. Paired tests of genic differentiation for microsatellite loci indicate the existence of genetic population structure for this species, where significant differences exist between some southern and northern samples. Multivariate analysis (factorial correspondence analysis) of microsatellite variation showed differentiation between the Pacific and the Atlantic populations. Analysis of the mitochondrial variation confirmed the microsatellite analysis of population structure, and revealed some additional differentiation between northern and southern Atlantic samples and exclusive haplotypes in each region. These findings suggest that the species should be managed as north–south separate stocks in the Atlantic Ocean.  相似文献   
106.
应用扫海面积法,并根据鱼类和文昌鱼栖息特点,采用了不同拖网取样方式,对胶州湾外南沙周围24km^2水域5、6月渔业资源数量与文昌鱼(Branchiostoma belcheri Gary)数量进行了调查评估。5月捕获的鱼类共28种,总资源量275479kg,其中玉筋鱼居第1位,资源量265200kg。捕获的无脊椎动物共13种,总资源量3489kg。6月文昌鱼数量约为18720000尾。同时,还指出了栖息环境面临的问题以及保护栖息环境的重要性和必要性。  相似文献   
107.
Reef fish, corals, and other marine invertebrate species associated with coral reefs need to be managed in a sustainable manner to halt destructive fishing in the Philippines and other Southeast Asian countries. As part of the Coastal Communities Empowerment Project, the International Marinelife Alliance (IMA) plans to implement Territorial Use Rights in Fisheries (TURFs) to help manage municipal waters; while creating alternative livelihoods for small-scale fishermen and their families. Changes to the Local Government Code allow Philippine municipal councils to regulate fishing and mariculture in waters within 15km from shore. The councils can lease TURFs to local fisherfolk and prevent their use by those outside the community. The IMA plans to help create several types of TURFs. These include TURFs used by aquarium-fish collectors, for rearing giant clams, and for farming live rock and coral fragments. The TURFs are part of a larger strategy to conserve marine biodiversity, protect and restore marine habitats, and promote sustainable use of marine resources by local people. Fish and invertebrates harvested from the TURFs will be used in programs to restore marine habitats and to generate income from exports that supply the aquarium trade.  相似文献   
108.
SCI源期刊中的水产科技期刊   总被引:2,自引:0,他引:2  
本文简要介绍了SCI特点及200年SCI-Expanded源期刊中收录的水产科技期刊及其评价指标。  相似文献   
109.
科学有效的渔业资源评估与管理是实现渔业资源可持续开发和利用的重要保障。传统的渔业资源评估与管理基于不变性假设,认为关键种群动力学过程不随时间发生变化。随着气候变化和人类活动的影响,种群的关键动力学过程可能随时间发生系统性的变化,形成非静态种群动力学过程,并在很大程度上颠覆了传统的不变性假设。本文结合近年来国际相关领域的研究成果,系统地阐述了非静态种群动力学过程的形成机制以及其对渔业资源评估模型、生物学参考点和渔业管理理念的影响。分析认为,在非静态种群动力学过程下,渔业资源评估模型和生物学参考点都需要考虑到关键种群动力学过程的时间变化,需要通过引入外部环境变量或者随时间变化的种群动力学参数,来应对非静态种群动力学过程对资源评估与管理带来的影响。研究建议,基于弹性的渔业管理是我们未来应对非静态种群动力学过程、维持渔业社会-生态系统稳定和健康的重要发展方向。  相似文献   
110.
The world's fisheries are under severe pressure. Yet, according to the marine trophic index, the health and stability of marine ecosystems vary greatly across countries. The argument developed and tested in this article holds that some of the sources of this variation can potentially be derived from differences in the character of two fundamental relationships in society – a horizontal one between resource users and a vertical relationship between the government and the resource users. The empirical analysis focuses on sub‐Saharan Africa and finds that levels of ethnic and linguistic heterogeneity and levels of democracy in the year that each country declared its exclusive economic zone have a close relationship with ensuing marine exploitation patterns.  相似文献   
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