Regional Analysis of Virtual Water Flow in View of Crop Consumption

It is important to identify virtual water for crop production ( P vw ) and consumption ( C vw ) and to analyse the virtual water flow among regions for a better understanding of water resource use. The estimation of virtual water flow in a basin or between regions of a basin can contribute to finding options for water‐saving strategies, such as changing cropping pattern and land use. The objective of this study was to analyse virtual water flow by using P vw , C vw and virtual water content (VWC). VWC of a product is the amount of fresh water required to produce the product, expressed as m 3 t − 1 . The virtual water consumption rate in this study is defined as C vw / P vw , which indicates the extent of water shortage and self‐sufficiency of water use in a region. The C vw and P vw of 16 regions were computed and the virtual water flow in the Han and Nakdong River basins was analysed. The analysis indicated that a shift of rice cultivation between the upper and the lower regions of these basins can save between 503 and 752 Mm 3 of VW in ideal conditions. Virtual water analysis can be useful for finding solutions to improve water productivity at basin level and to reduce pressure on local water resources. Copyright © 2016 John Wiley & Sons, Ltd.