Spatial and temporal analyses of the wheat virtual water variations in Sistan and Blouchestan Province

The spatial and temporal variation of wheat virtual water، as one of the strategic product in Sistan and Blouchestan Province، has been investigated. To this end، the 12 year weather data، yield، cultivated area and irrigation method were used. The 12 year average of the net wheat water use was 303 million cube meter from which 9. 2 percentage was supplied by green water. Regardless of the irrigation efficiency، the net virtual water varied among 1. 59 (Khash City) to 6. 18 (Zabol City) meter cube per kilogram and its 12-year average was 3. 42 meter cube per kilogram in the whole province. Considering the real water volume allocated to the wheat، the 12-year average of the imported and exported virtual water in the entire province was 1043 and 43. 2 million cube meter، respectively، and Zahedan and Zehak were، respectively، the biggest importer and exporter of the virtual water. Results showed that decreasing the water loss by 10 percentages through improving irrigation efficiency would increase the sel-sufficiency in whaet production by 18. 2% and decrease the dependency to virtual water import by 3. 62 percentages due to 11. 7 percentage decrease in wheat water use.