Multi-Objective Optimization Analysis of Cropping Patterns in the Helmand Basin: The Role of Virtual Water Import Strategy

Agriculture is the main economic pillar of the Helmand Basin; however, it faces severe water scarcity due to unsustainable consumption. Previous studies have optimized cropping patterns based on economic and water factors in arid regions. However, the unique conditions of Helmand require a multi-objective optimization approach that integrates economic, ecological, and environmental factors. This study develops a multi-objective mathematical model to determine the optimal cropping pattern for Helmand to maximize farmer profits while minimizing water consumption and environmental impacts. The model simulates cropping areas for major regional crops using multi-objective linear programming. In this regard, to obtain the optimal cultivation pattern with the desired objectives, the genetic algorithm was used as a random optimization method. The desired information was obtained from the Agricultural and Jihad Organization and Regional Water of Sistan and Baluchestan Province, and the relevant calculations were performed in MATLAB and CROPWAT software. The crop year determined in this study is 2018-2019 and the selected crops include wheat, corn, barley, black grapes, cucumber, eggplant, onion, legumes, and medicinal plants. Results indicate that the optimal cropping pattern reduces annual water consumption by 29%, nitrogen leaching by up to 14%, and increases economic yield by 11% compared to current practices. Virtual water imports of wheat and corn reduce local water consumption by 18% and improve economic yield by up to 5%. This integrated modeling approach provides data-driven scenario-based decision support for guiding policies on optimal cropping strategies. The findings demonstrate the potential of multi-objective optimization combined with virtual water imports to sustainably enhance agriculture despite water scarcity. This study can be used as a road map for policy makers and farmers to improve and sustain agriculture in the Hirmand basin.