Introduction to Coping with water scarcity

Worldwide, water for agriculture is becoming increasingly scarce. Though there is no systematic inventory, definition, or quantification of water scarcity in rice-growing areas, it is estimated that, by 2025, 15-20 million ha of irrigated rice will suffer some degree of water scarcity. The causes for water scarcity are diverse and location-specific, but include decreasing resources (e.g., falling groundwater tables, silting of reservoirs), decreasing quality (e.g., chemical pollution, salinization), malfunctioning of irrigation systems, and increased competition from other sectors such as urban and industrial users. The consequence of water scarcity is that water may not always be available in sufficient amounts and at the right time to realize the best management practice for water (which is basically, continuous flooding of the fields with 2-5 cm of water depth). A suite of options are available to help farmers cope with different degrees and forms of water scarcity. It starts with sound practices during land preparation and pre-planting activities. During crop growth, techniques such as saturated soil culture, alternate wetting and drying, raised beds, mulching, and aerobic rice exist or are being developed. A full manual on managing scarce water in rice production can be downloaded through: