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DocumentOther documentPreliminary stock assessment for the cuttlefish Sepia pharaonis taken off the coast of the People's Democratic Republic of Yemen 1979
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No results found.This paper describes a preliminary stock assessment for the cuttlefish Sepia pharaonis inhabiting waters off the People’s Democratic Republic of Yemen. It is principally based on the catch and effort records for the commercial fleet. -
DocumentOther documentSecond report of mesh selection studies conducted in the People's Democratic Republic of Yemen on the cuttlefish Sepia pharaonis 1982
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No results found.This paper describes a repeat of an earlier study by the authors, concerning the mesh selection properties of trawl cod-ends of various mesh sizes on the cuttlefish Sepia pharaonic. A brief resume of the findings is as follows: the estimated 50% selection lengths with 95% confidence limits for single braided polyethylene cod-ends of 12.4 cm, 13.6 cm and 16.8 cm mesh sizes were 17.87+0.28 cm, 20.74+- 0.53 cm and 26.95+-1.07 cm; the 50% selection lengths and selection ranges were very similar to t hose obtained in the earlier study in respect to the 12.4 cm cod-end, but higher in respect to the 13.6 cm cod-end; the 16.8 cm cod-end had not been previously used; the previously held assumption that the 50% selection lengths and cod-end mesh sizes were proportionally related was seen as inappropriate, and hence also the estimation of selection factors; the more appropriate relationship was seen to be one of non-proportional linearity, and the regression equation considered most compatible wit h the observations as 50% selection length (cm)=2.03 mesh size(cm) -7.41; for a chosen value of the 50% selection length, this equation gives substantially different values for the choice of appropriate cod-end mesh size, than the selection factors estimated from the earlier study. -
DocumentOther documentThird report of mesh selection studies conducted in the People's Democratic Republic of Yemen on the cuttlefish Sepia pharaonis 1983
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No results found.The results of a third cod-end mesh selection trial involving the alternate haul method are described. All cod-ends were made from single braided polyetheylene, and the mesh sizes used were 7.0 cm, 10.3 cm, 12.4 cm, 14.1 cm, 15.2 cm, and 16.9 cm; the smallest size being taken as the standard against which the others were compared. The relationship between the 50% selection lengths and mesh sizes, was found not to be different from those of the earlier two trials; combining the results from all t rials gave: 50% selection length (cm) = 2.15 x mesh size (cm) - 9.34; whose correlation coefficient is highly significant (at P<0.05).
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BookletCorporate general interestEmissions due to agriculture
Global, regional and country trends 2000–2018
2021Also available in:
No results found.The FAOSTAT emissions database is composed of several data domains covering the categories of the IPCC Agriculture, Forestry and Other Land Use (AFOLU) sector of the national GHG inventory. Energy use in agriculture is additionally included as relevant to emissions from agriculture as an economic production sector under the ISIC A statistical classification, though recognizing that, in terms of IPCC, they are instead part of the Energy sector of the national GHG inventory. FAO emissions estimates are available over the period 1961–2018 for agriculture production processes from crop and livestock activities. Land use emissions and removals are generally available only for the period 1990–2019. This analytical brief focuses on overall trends over the period 2000–2018. -
LetterLetter to Prof. G. Montemartini 1906
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No results found.Lubin discusses his financial limitations, his willingness to assist the IIA, and conditions for his potential move to Rome. -
Book (series)FlagshipThe State of Food Security and Nutrition in the World 2021
Transforming food systems for food security, improved nutrition and affordable healthy diets for all
2021In recent years, several major drivers have put the world off track to ending world hunger and malnutrition in all its forms by 2030. The challenges have grown with the COVID-19 pandemic and related containment measures. This report presents the first global assessment of food insecurity and malnutrition for 2020 and offers some indication of what hunger might look like by 2030 in a scenario further complicated by the enduring effects of the COVID-19 pandemic. It also includes new estimates of the cost and affordability of healthy diets, which provide an important link between the food security and nutrition indicators and the analysis of their trends. Altogether, the report highlights the need for a deeper reflection on how to better address the global food security and nutrition situation.To understand how hunger and malnutrition have reached these critical levels, this report draws on the analyses of the past four editions, which have produced a vast, evidence-based body of knowledge of the major drivers behind the recent changes in food security and nutrition. These drivers, which are increasing in frequency and intensity, include conflicts, climate variability and extremes, and economic slowdowns and downturns – all exacerbated by the underlying causes of poverty and very high and persistent levels of inequality. In addition, millions of people around the world suffer from food insecurity and different forms of malnutrition because they cannot afford the cost of healthy diets. From a synthesized understanding of this knowledge, updates and additional analyses are generated to create a holistic view of the combined effects of these drivers, both on each other and on food systems, and how they negatively affect food security and nutrition around the world.In turn, the evidence informs an in-depth look at how to move from silo solutions to integrated food systems solutions. In this regard, the report proposes transformative pathways that specifically address the challenges posed by the major drivers, also highlighting the types of policy and investment portfolios required to transform food systems for food security, improved nutrition, and affordable healthy diets for all. The report observes that, while the pandemic has caused major setbacks, there is much to be learned from the vulnerabilities and inequalities it has laid bare. If taken to heart, these new insights and wisdom can help get the world back on track towards the goal of ending hunger, food insecurity, and malnutrition in all its forms.