Productive Water Use in Rice Production

Summary

It is crucial for food security to produce more rice with decreasing availability of water for rice production. This article seeks to answer the question “Does rice really require an abundance of water?” and discusses strategies and options to make rice production more water-efficient. It analyzes the effectiveness of prospective technological innovations in increasing the rice yield per unit water evapotran-spired and reducing the water inflow to the rice fields. Possible impacts of these innovations on fertilizer-use efficiency, labor input, weed control, and water availability at locations downstream of the site of interest are discussed. Constraints to implementing these innovations include our inability to evaluate their on-farm and off-site effects and lacks of incentives for farmers and system managers to improve irrigation performance.

Key Words:

• Water productivity
• water use efficiency
• evapotranspiration
• irrigation
• percolation