Development of a regionally sensitive water-productivity indicator to identify sustainable practices for sugarcane growers.

Standards that credibly and effectively certify sustainable commodity production are important to both producers and consumers. Agriculture is the dominant user of water worldwide, so water sustainability in agriculture is an area of particular interest. In conjunction with Bonsucro, a sustainability standard setting body for the sugarcane sector, an indicator was developed to ensure that water consumed in sugarcane cultivation is used productively (i.e., that producers achieve high "crop per drop"). To be easily measurable, sugarcane water productivity was adapted so that yield could be compared within a climate zone in which water demand is assumed to be uniform. The indicator identifies efficient performers, defined as those exceeding median historical yield in each climate zone, with rainfed and irrigated systems evaluated separately. Both the expert-driven and stakeholder-driven aspects of standard development are discussed. We address the advantages and the limitations of this new indicator, its potential application to other crops, and the possibility of improvement to include further criteria. Integr Environ Assess Manag 2016;12:811-820.