The salinity problem in irrigation:an introductory review; evaluation and classification of water quality for irrigation;effescts of salinity and soil water regime on crop yelds; irrigation and soil salinity; fertilization and salinity;impact of irrigation on the quality of groundwater and river flows; economic evaluation of irrigation with saline water withim the framework of farm,Economic impacts of regional economic effects of changes in irrigation water salinity within a river basin framework; the case of the colorado river.

This open access book is an outcome of the collaboration between the Soil and Water Management & Crop Nutrition Section, Joint FAO/IAEA Division of Nuclear Techniques in Food and Agriculture, Department of Nuclear Sciences and Applications, International Atomic Energy Agency (IAEA), Vienna, Austria, and Dr. Shabbir A Shahid, Senior Salinity Management Expert, Freelancer based in United Arab Emirates.The objective of this book is to develop protocols for salinity and sodicity assessment and develop mitigation and adaptation measures to use saline and sodic soils sustainably. The focus is on important issues related to salinity and sodicity and to describe these in an easy and user friendly way. The information has been compiled from the latest published literature and from the authors’ publications specific to the subject matter. The book consists of six chapters. Chapter 1 introduces the terms salinity and sodicity and describes various salinity classification systems commonly used around the world. Chapter 2 reviews global distribution of salinization and socioeconomic aspects related to salinity and crop production. Chapters 3 covers comprehensively salinity and sodicity adaptation and mitigation options including physical, chemical, hydrological and biological methods. Chapter 4 discusses the efforts that have been made to demonstrate the development of soil salinity zones under different irrigation systems. Chapter 5 discusses the quality of irrigation water, boron toxicity and relative tolerance to boron, the effects of chlorides on crops. Chapter 6 introduces the role of nuclear techniques in saline agriculture.

Human-induced salinisation is a major threat to the world's land and water resources. Inadequate development of irrigation projects, inefficient irrigation, lack of proper drainage, and environmental mismanagement such as the clearing of native vegetation, are responsible for the loss of millions of hectares of agricultural and grazing land, as well as the misuse of scarce water resources. The first part of this book analyses the problem in the context of the world's population, its climate and its land and water resources. It reviews irrigation methods and crop water requirements, the processes of salinisation, and its management. The second part describes irrigated land, dryland and water-resource salinity problems in 11 countries, which contain approximately 70 per cent of the world's irrigated land. In each case study, background data, environmental conditions and past management practices are given to provide an understanding of why salinity occurs in particular places, and of the management methods employed against it.

This paper presents a synthesis of 15 success stories in the production, processing, and marketing of high-value food products (HVF) in developing countries in Asia, Latin America, and Africa. High-value food products, such as fresh and processed fruits and vegetables, meats, fish, dairy products, and vegetable oils, are defined as having high intrinsic value or a high rate of value added through processing. Trade in these products has expanded while trade and prices for other agricultural products, such as most staple crops, have stagnated or declined. The growing trade in HVF has prompted policymakers in developing countries to examine more closely how they can expand and diversify their exports of these products. This study explores the technical, organizational, and commercial challenges facing those in HVF export development. It identifies common market and institutional factors that have contributed to the growth and international competitiveness in HVF trade. Particular note is made of the roles of the private and public sectors and of the effect of the policy environment. It examines the effect of institutional coordination on the stages of production, processing, and trade. An annex summarizes 12 case studies of the development and performance of food commodity markets. It includes export of fresh vegetables from Kenya in the 1960s, shrimp from Thailand in the 1970s, and processed tomatoes from Chile in the 1980s.

This publication contains guidelines to sustain irrigated agriculture and protect water resources from the negative impacts of agricultural drainage water disposal. Using case studies from Central Asia, Egypt, India, Pakistan and the US, this study highlights four broad groups of drainage water management options and provides information to enable assessment of their impact and contribution towards development goals and to facilitate the preparation of drainage water management plans and designs. The options are: water conservation, drainage water re-use, drainage water disposal and drainage water treatment. The full texts of the case studies can be found on the attached CD-ROM.

Irrigation has long played a key role in feeding expanding populations and is expected to play a still greater role in the future. However, is it sustainable? Can it remain in existence and function continuously and indefinitely? Some pessimists doubt that it is. This volume presents a more positive approach with carefully conditional optimism. It takes the diffuse, voluminous and disparate facts and combines them in a unified exposition. It merges physico-chemical, agronomic, environmental and economic principles into practical recommendations to help ensure the long-term viability and productivity of irrigated agriculture in arid and semiarid regions.

The papers assembled here cover topics such as technological advances in soil salinity mapping and monitoring, management and reclamation of salt-affected soils, use of marginal quality water for crop production, salt-tolerance mechanisms in plants, biosaline agriculture and agroforestry, microbiological interventions for marginal soils, opportunities and challenges in using marginal waters, and soil and water management in irrigated agriculture.

Salinization of soils is a major threat to irrigated agriculture and counteracts the targets of costly public infrastructure investments. In this study, salinization is regarded as the outcome of an institutional arrangement which impedes the effective implementation of well-known and well-established control measures be they technical, managerial or economic. In public irrigation systems neither the management units nor the farmers are offered any incentives towards the control of high groundwater levels and salinization if the management units are embedded in a highly centralized non-market institutional setting. The author answers the question under which conditions management units and irrigators are active in halting and reversing the process of salinization.

This book documents the history of irrigated agriculture and drainage in the San Joaquin Valley, and describes the hydrology and biogeochemical processes of salts and selenium, remediation technologies for salts and trace elements and policy and management options. The contents are comprised of fourteen chapter-length independent treatises, each depicting with fresh perspective a distinctive salinity drainage topic. The opening chapters detail the evolution of irrigated agriculture, and depict the geochemical and hydrological processes that define the San Joaquin Valley, including the physics, chemistry, and biology attributes that impact water management policies and strategies. Next, the contributors address the biogeochemistry of selenium, the role of plants in absorbing it from soils, and the processes involved in retaining and concentrating dissolved salts in drainage water. Further chapters describe on-farm and plot-level irrigation provisions to reduce agricultural drainage outputs and examine their effects on plant performance. This volume offers realistic policy analysis of water management options for irrigated agriculture in the Valley and assesses their respective outcomes, if implemented. Also included is an international perspective on the sustainability of irrigated agriculture there.