Estimation and zoning of water footprints in wheat production (Case study: Khuzestan Province)

Considering the importance and special status, the critical conditions of water scarcity in production systems, and the lack of traceability of wheat water in Khuzestan, in this study, green, blue and gray water footprints of wheat product were estimated. The studied areas were Ahvaz, Dezful, Shooshtar, Behbahan, Izeh and Khorramshahr. The total water footprint of wheat was obtained from the sum of green, blue and grey water footprint. Then, the relationship between wheat water footprint and actual yield was compared. The results showed that among the study areas, Khorramshahr needed more water (1704 m3 t-1) to produce the product and thereafter, Ahvaz (1228 m3 t-1), Behbahan (1083 m3 t-1), Izeh (1012 m3 t-1), Dezful (959 m3 t-1) and Shushtar (915 m3 t-1). To produce 1 ton of wheat, Izeh needs 778 cubic meters of green water, and after that, Khorramshahr was ranked second with 458 cubic meters of green water. However, Izeh had the lowest blue water footprint, and the zoning of Khuzestan province in terms of the blue water footprint of wheat showed that the blue water footprint in the southern half of the province is more than the northern half. Grey water footprints also follow a similar blue-water trend. Whereas Shooshtar has the lowest water footprint with the highest yield, and Khorramshahr has the lowest wheat yield and the highest water footprint among the other studied cities.