Evaluation of Coping Policies with Water Scarcity in Cereal Production Based on Water-Food-Energy Nexus Mina Tayyebi Mina.tayyebi@yahoo.com September, 21, 2020 Department of Civil Engineering Isfahan University of Technology, Isfahan 84156-83111, Iran Degree: M.Sc. Language: Farsi Supervisor: A.Ahmadi (aahmadi@cc.iut.ac.ir) Demand for water, food and energy resources, human survival essential needs, is increasing. is increasing. Due to the internal relationships and systemic complexities of water, food and energy resources, the water, food and energy nexus (WFE nexus) has been developed to draw the attention of decision-makers to the cross-sectoral integration, interlinkages and external consequences of processes related to these resources. Agriculture is also closely related to these three sources. Because on the one hand, the food production systems are based on agriculture, on the other hand, agriculture which is the greatest consumer of fresh water in the world is known as one of the most important causes of water stress. As a result, it is necessary to use the WFE nexus for evaluating the agricultural management practices to examine the effect of strategies, which increase access to one resource, on the security of other resources. In this study, adaptation policies to water scarcity in the agricultural sector have been evaluated to investigate the consequences of these strategies on the integrated agriculture system. First, the data were collected, then due to the conflicts in agriculture, a multi-objective optimization model was developed. Finally, by creating a variety of strategies, the results of the optimization model are compared to identify trade-offs and synergies between resources based on an indicators framework. To analyze the performance of the research methodology, Iran has been studied as a case. The multi-objective optimization model has been implemented with the two objectives of maximizing the economic profit of agriculture and minimizing the decrease of groundwater level during ten years. The results of the baseline scenario show that an average of 14 million tons of irrigated cereal is produced annually in Iran, which requires an average of 423 gigawatt-hours of electricity and 35,228 million cubic meters of water per year to bring an average annual economic profit of 16045 billion rials. As the first scenario to increase irrigation efficiency up to the horizon of 1420, the model has been implemented and the results indicate the improvement of the agriculture system in all aspects. So that this strategy, while increasing 2.6% in the average annual economic profit compared to the baseline scenario, reduces the average annual consumption of water and electricity resources by 12.4% and 18.9%, respectively. Due to the efficiency of this strategy, in the next step, other scenarios are combined with the first scenario. Cropping pattern modification is one of the most important coping policies with water scarcity. In this regard, the ban on rice cultivation in climates incompatible with this crop, along with increasing the agriculture efficiency, as a first combined scenario, is included in the model. This scenario has reduced the consumption of water and electricity resources by 21.8% and 21% but has reduced the financial profit of agriculture by 4.5%. The second combined scenario was receiving 200 rials per cubic meter of groundwater and increasing agricultural efficiency. Although this scenario, in addition to reducing the consumption of environmental resources, has increased the area under irrigated cereals by 1.16% but has reduced the income of cereals to 4.6% less than the baseline scenario. As a result, it can be seen that strategies that improve the security of water and energy resources, even if they do not reduce the area under cultivation, can damage the livelihood of farmers. Therefore, in addition to reducing the stress of natural resources, it is necessary to review the financial structure of agriculture in Iran. In the third combination strategy, due to the increase in agricultural efficiency, farmers have been allowed to increase the area under cultivation. This scenario increases water and energy consumption by 2.5 and 1.5 times compared to the first combined scenario and by 1.5 and 1.5 times compared to the second combined scenario, but causes an 8% increase in economic profits and production compared to the baseline scenario. Therefore, it is estimated that if irrigation efficiency increases but water and energy resources do not change, the increased efficiency in the long term will not have a significant impact on increasing resource security, but with unsustainable agricultural development resources stress are also intensified. Key Words: Water, Energy Food Nexus, Multi-Objective Optimization, Sustainable Agriculture, Coping with Water Scarcity