Evaluation of management policies to simultaneously maintain groundwater resources and farmers' livelihoods Using the System dynamics and Game Theory

The water crisis caused by rapid population growth, unbalanced economic development, climate change, and inefficient water resources management is recognized as the most significant threat in recent century. Groundwater resources, one of the most important available water resources, have faced many challenges in recent years as 404 out of 609 plains have been declared. The agricultural sector, as the main consumer of groundwater, has played a major role in creating this crisis. In the research, the impacts of different non-strategic crops on groundwater level and farmers’ income have been investigated using long term system dynamics. The Qazvin Aquifer, which has been declared a prohibited plain since 1962, was picked as a case study. After collecting time series data and preparing it, the 15- year causality model was built up using VENSIMPLE software, which calibrated using a genetic algorithm. The results showed that the transfer of water from Taleghan dam to Qazvin Plain helped to reduce ten meters of drawdown during a 15- year period. The impact of 17 different crops on groundwater level and farmers’ net income were researched for Qazvin Plain. The results showed that farmers’ income is most impacted by the grape crop with a high economic water footprint, while groundwater level is most affected by the wheat crop. Next, the influence of the removal of non-strategic crops with high water requirement was evaluated in the plain. The results showed that removing non-strategic crops is selected as optimal scenario by applying four conflict resolution methods in symmetric conflicts.