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No Thumbnail AvailableProjectProgramme / project reportReport of the Technical Consultation on the enhancement of small water body fisheries in southern Africa - Harare, Zimbabwe, 25-29 January, 1993 1994
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No Thumbnail AvailableProjectProgramme / project reportThe use of multimesh gillnets for sampling fish stocks in reservoirs in Southern Africa 1995
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No results found.In order improve the management of a fishery it is necessary to determine which species are present and in what quantities. Sampling of the fish stock is thus needed. For monitoring the effects of certain management strategies, it will also be necessary to gather information concerning the fish stocks. Gillnets are often used for sampling fish stocks because they are easy to use, relatively cheap, catch a wide variety of species, and their use can be standardized. Gillnets are however, selective towards the species they catch, the size of fish they catch and the amounts of fish they catch. Also outside factors influence the effectiveness of the nets. ALCOM used multimesh gillnets in 34 reservoirs in 5 countries in southern Africa over a period of 5 years to collect information on the fish stocks of these reservoirs. The analysis of the results of these samplings showed that the gears were useful to collect general information of the fish stocks, but also demonstrated that the catch per unit of effort could not be used as a reliable indication of abundance. The reasons for this were that the fluctuation in the catches were too great, not all species could be sampled with the required precision and, although a wide range of mesh sizes were used, the gears were still size selective. Furthermore it was agrued that the effects on the fish population of different management strategies would not be detected by sampling with gillnets alone. The effects of outside factors, and especia lly of the water level fluctuation of the reservoirs, would easily confound the effects of the fisheries management on the reservoirs. It was recommended to concentrate the studies on the target species, to determine the effects of the water fluctuatiuon of fish production, and to use the existing fishery in the collection of data. -
No Thumbnail AvailableProjectProgramme / project reportReport on the Seminar on Fish Production in Lowlands Reservoirs, Lesotho - Maseru Sun Cabanas, Maseru, 13-14 Juen 1994 1995
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Book (stand-alone)Flagship2015–16年农产品市场状况
贸易与粮食安全：更好地平衡国家重点与集体利益
2015全球农产品和粮食产品贸易已在最近几十年取得快速增长，各国作为出口或进口方越来越多地参与这一贸易进程。这种趋势预计将在今后几十年中持续。因此，贸易将在全球各区域对粮食安全的程度和性质产生越来越重要的影响。我们面临的挑战就是确保农产品贸易的扩大能对消除饥饿、粮食不安全和营养不良起到促进作用，而不是阻碍作用。 本版《农产品市场状况》旨在缓解目前各方在农产品贸易对粮食安全产生的影响以及如何管理农产品贸易以确保贸易开放度的增加能惠及所有国家等问题上出现的观点两极分化现象。本书通过就一系列话题举证和说明，努力促成各方就政策选择开展有实证依据的辩论，并在政策选择过程中努力实现必要的改进。 -
IndexesLibrary Classified Catalogue (1)/ Bibliothèque de catalogues systématiques (1) 1948
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No results found.The Protocol of 8-9 July 1946 relative to the dissolution of the International Institute of Agriculture, transferred the functions and assets of the said Institute to FAO. Of these assets, the Library is unquestionably the most outstanding and is a lasting record of the Institute's work and its achievement in the field of agriculture. This catalogue will undoubtedly contribute towards a better knowledge of this international Library. This volume in its present form, represents the systematic card-index, by subject of the Brussels Decimal Classification, in French and English, and it's supplemented by the general alphabetical index of authors.
This is Part 1 of 4 - Books - sections General, Bibliographies, Periodicals, Philosophy and Social Sciences.
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Book (series)Technical studyThe impact of climate variability and extremes on agriculture and food security - An analysis of the evidence and case studies
Background paper for The State of Food Security and Nutrition in the World 2018
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No results found.Global climate studies show that not only temperatures are increasing and precipitation levels are becoming more varied, all projections indicate these trends will continue. It is therefore imperative that we understand changes in climate over agricultural areas and their impacts on agriculture production and food security. This study presents new analysis on the impact of changing climate on agriculture and food security, by examining the evidence on recent climate variability and extremes over agricultural areas and the impact of these on agriculture and food security. It shows that more countries are exposed to increasing climate variability and extremes and the frequency (the number of years exposed in a five-year period) and intensity (the number of types of climate extremes in a five-year period) of exposure over agricultural areas have increased. The findings of this study are compelling and bring urgency to the fact that climate variability and extremes are proliferating and intensifying and are contributing to a rise in global hunger. The world’s 2.5 billion small-scale farmers, herders, fishers, and forest-dependent people, who derive their food and income from renewable natural resources, are most at risk and affected. Actions to strengthen the resilience of livelihoods and food systems to climate variability and extremes urgently need to be scaled up and accelerated.