Comparison of water productivity indices and virtual water in major rice producing provinces in Iran

Drought and water scarcity in Iran is a climatic reality, and given the increasing need of different sectors for water, the problem of water scarcity in the coming years threatens the sustainability of cultivating some strategic crops with high water requirement. Rice cultivation requires high irrigation and is susceptible to water stress, so the best way to save water is to improve its water productivity. In this regard, in the present study, the estimation of rice water productivity indices was done in four major rice producing provinces of the country, including: Guilan, Mazandaran, Khuzestan, and Fars provinces. This study uses cross-sectional data from 2014-2015 rice production cost plan of Ministry of Jihad-e-Agriculture collected by cluster sampling from each province's farmers and estimated water requirement through remote sensing to calculate water productivity indices. The results showed that Mazandaran and Guilan provinces had the highest water productivity (yield/water requirement) with average of 0.99 and 0.88 kg/m3, respectively, Fars and Khuzestan provinces were in third and fourth places with averages of 0.65 and 0.52 kg/m3, respectively. The results showed that the highest net benefit of water consumption were in Guilan and Mazandaran provinces with averages of 9310 and 6590 Rials/m3, respectively. According to the results of this study, it is recommended to limit rice cultivation in Khuzestan and Fars provinces, especially in years with water deficiency.