Advances in assessment indicators of irrigation water use efficiency

The definitions and their utlization about the assessment indicators of the irrigation water use efficiency (IWUE) are reviewed. The disadvantages and their use conditions of the existing IWUE are analyzed. We conclude that no indicators can be used to quantify IWUE in any conditions. Firstly, the connotations of different nomenclature of IWUE are ambiguity, which results in the use interchangeably of various terms regardless of the precise implications of their recommendations. Secondly, some new concepts of assessment framework and indicators are right, but it is difficult to determine the components in the framework, and thus not suitable for the utilization in water management in an irrigation system. Finally, we point out the essentiality of giving the precise implications of the existing IWUEs and their specific use conditions, investigate their relationships and affecting factors, and propose the methodology of evaluating the water saving potiential.