Sustainable optimization of regional agricultural water use by developing a two-level optimization model

The present study applies a two-level optimization model. The first-level objective is to optimize the cropping pattern in the whole grid based on the amount of water consumed per crop. The second-level objective is to maximize the profit and minimize the disruption of water resource sustainability in branch and distributary canals in the district of Qazvin, Iran. Based on the results of the first-level objective, the scenario of a 10% reduction in irrigation water increased economic productivity at various levels by an average of 25 USD per cubic meter of water while maintaining proper income. The second-level results indicated a 64% increase in net profit compared to the profit associated with the existing cropping pattern due to (a) the reduction of crops of low profitability in the cultivated area and (b) the increase of high-profitability crops in the cultivated area. On the other hand, according to the considered objective functions, the amount of water consumed in optimal conditions reduced from 100 of water allocated to 80%.