Virtual water flows and water-footprint of agricultural crop production, import and export: A case study for Israel

Agriculture is the largest global consumer of freshwater. As the volume of international trade continues to rise, so does the understanding that trade of water-intensive crops from areas with high precipitation, to arid regions can help mitigate water scarcity, highlighting the importance of crop water accounting. Virtual-Water, or Water-Footprint [WF] of agricultural crops, is a powerful indicator for assessing the extent of water use by plants, contamination of water bodies by agricultural practices and trade between countries, which underlies any international trade of crops. Most available studies of virtual-water flows by import/export of agricultural commodities were based on global databases, which are considered to be of limited accuracy. The present study analyzes the WF of crop production, import, and export on a country level, using Israel as a case study, comparing data from two high-resolution local databases and two global datasets. Results for local datasets demonstrate a WF of similar to 1200 Million Cubic Meters [MCM]/year) for total crop production, similar to 1000 MCM/year for import and similar to 250 MCM/year for export. Fruits and vegetables comprise similar to 80% of Export WF (similar to 200 MCM/year), similar to 50% of crop production and only similar to 20% of the imports. Economic Water Productivity [EWP] ($/m(3)) for fruits and vegetables is 1.5 higher compared to other crops. Moreover, the results based on local and global datasets varied significantly, demonstrating the importance of developing high-resolution local datasets based on local crop coefficients. Performing high resolution WF analysis can help in developing agricultural policies that include support for low WF/high EWP and limit high WF/low EWP crop export, where water availability is limited. (c) 2017 Elsevier B.V. All rights reserved.