Sustainable Crop Production using Saline and Sodic Irrigation Waters

Abstract

Irrigation water is one of the most critical and scarce resource for agricultural production in arid and semiarid regions. Enhancing productivity in arid regions largely depends upon the ability to enlarge water resource by better rainwater management and development of groundwater. The lack of good water supplies for irrigated agriculture in now becoming a major issue that is forcing farmers to use low quality waters. Nonetheless injudicious use of sodic and saline waters poses grave risks to soil health by deteriorating soil physical, chemical and biological properties. Development of salinity, sodicity and toxicity problems not only reduces crop productivity but also limits crop choice. It is therefore imperative that irrigation development plans are carefully drawn and executed to sustain crop production and to minimize salinization and deterioration of soil physical conditions over the long-term. Alternative options have now emerged to safely use waters otherwise designated unfit. This has led to the replacement of too conservative water quality standards by site-specific guidelines where factors like soil texture, rainfall and crop tolerance have been given due consideration. Nevertheless, appropriate selection of crops, improvement in water and fertility management, maintenance of soil structure and tail water return systems are still necessary. Examples of the available technologies and practices for sustaining irrigation with these waters are given in this article. Economic development, social preferences and resource endowments are region-specific, and are thus expected to influence the selection and adoption of technology packages. Although the emphasis is placed on experiences in India, such practices are appropriate for many other arid and semi-arid regions where irrigated agriculture is confronting the similar challenges.