Investigating Water Resources and Agricultural Economy by Hydro-Economic Modeling in the Mahabad Basin Located in the South of the Lake Urmia

Controlling water consumption in agricultural sector requires an appropriate understanding of the interplay between water resources, water consumption and agricultural economy. This study aimed to develop two hydrological and agro-economic models in the Mahabad study area (located in south of the Lake Urmia) in order to investigate the effects of climate change on the volume of water entering the Mahabad dam, explore long-term changes in gross irrigation needs, and study the impact of the crop pattern change on the gross irrigation need and the agricultural economy of the region. The results showed that if the agricultural water consumptions are controlled up to the year 1419 (Persian Calendar), the increase in the volume of water entering the Mahabad Dam under the climate change scenarios A1B and B1 can reduce the current withdrawal from surface and groundwater sources. It would also promote the possibility of release from the Mahabad Dam to partially provide the environmental flow of Lake Urmia. We further found that the net value of the crop production in the past years was much lower for wheat and barley compared to other crops, which explains the lack of economic justification for the cultivation of these two crops. The amount of production and the net value of sugar beet production showed a significant growing trend, which is in a clear contradiction to the policies of reducing agricultural water consumption by 40%. In case of increasing the cultivated area of water-rich crops in the region, the greatest stress on groundwater resources will be under the climate change scenario A2.