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Book (stand-alone)Technical bookCrop water requirements 1992
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No results found.This publication is intended to provide guidance in determining crop water requirements and their application in planning, design and operation of irrigation projects. Part 1.1 presents suggested methods to derive crop water requirements. The use of four well-known methods for determining such requirements is defined to obtain reference crop evapotranspiration (ETo), which denotes the level of evapotranspiration for different climatic conditions. These methods are the Bla.ney- Criddl e, the Radiation, the Penman and Pan Evaporation methods, each requiring a different set of climatic data. To derive the evapotranspiration for a specific crop, relationships between crop evapotran.spiration (ETcrop) and reference crop evapotranspiration (ETo) are given in Part I . 2 for different crops , stages of growth, length of growing season and prevailing climatic conditions. The effect of local conditions on crop water requirements is given in Part 1.3; this includes local va riation in climate, advection, soil water availability and agronomic and irrigation methods and practices . Calculation procedures are presented together with examples. A detailed discussion on selection and calibration of the preSented methodologies together with the data sources is given in Appendix II. A computer programme on applying the different methods is given in Appendix III. Part 11 discusses the application of crop water requirements data in irrigationproject planning, des ign and operation.. Part II. 1 deals v.rith deriving the field water balance, which in turn forms the basis for predicting season.al and peak irrigation supplies for general planning purposes. Attention is given to irrigation efficiency and water requirements for cultural practices and leaching of salts. In Part 11.2 methods are presented to arrive at field and scheme supply schedules with emphasis towards the field water balance and field irrigation management. Criteria are given fo r operating the canal system using different methods of water delivery, and for subsequent design parameters of the system. Suggestions are made in Part 11.3 on refinement of field and project supply schedules once the project is in operation. The presented guidelines are based on measured data and experience obtained covering a wide range of conditions. Local practical, technical, social a.nd economic considerations will, however, affect the planning criteria selected. Therefore c aution and a critical attitude should still be taken when applyin.g the presented methodology. -
No Thumbnail AvailableBook (stand-alone)ProceedingsIrrigation scheduling: From theory to practice. Proceedings 1996
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MeetingMeeting documentReport on the Expert Consultation on Procedures for Revision of FAO Guidelines for Prediction of Crop Water Requirements
Rome, Italy, 28-31 May 1990
1990Also available in:
No results found.In this series of publications, the FAQ methodology for the prediction of crop water requirements has been quite an outstanding example. The PAO-No. 24, as it has become known, has become an international standard, extensively used worldwide by irrigation engineers, agronomists, hydrologists and environmentalists. More than 20 000 copies of the publication have·been distributed in four languages. The methodology is commonly applied in many studies and development proposals, and endorsed by the major financing and development agencies as the recommended method. In many educational institutes and universities, the F AO methodology is part of the curriculum. To improve on the methodologies the collaboration of a wide range of resource people and institutions worldwide needed to be assured in order to establish accepted procedures to review the methodologies and update procedures for estimation of crop water requirements. Collaboration was established with the International Commission for Irrigation and Drainage, the American Societies for Civil and Agricultural Engineers and the World Meteorological Organization. To establish the wide forum required, F AO organized a consultation of eminent experts and researchers which was held from 28 to 31 May 1990 in Rome, Italy, to advise on procedures for review. Results on the outcome of the meeting incorporating the specific suggestions and recommendations are included in this report.
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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. -
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. -
Book (stand-alone)Technical bookThe future of food and agriculture - Trends and challenges 2017
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No results found.What will be needed to realize the vision of a world free from hunger and malnutrition? After shedding light on the nature of the challenges that agriculture and food systems are facing now and throughout the 21st century, the study provides insights into what is at stake and what needs to be done. “Business as usual” is not an option. Major transformations in agricultural systems, rural economies, and natural resources management are necessary. The present study was undertaken for the quadrennial review of FAO’s strategic framework and for the preparation of the Organization Medium-Term plan 2018-2021.