Optimal Crop Pattern Base on Climate-Smart Agriculture and Sustainable Water Resources Management

Introduction: Agriculture remains one of the most climate-vulnerable economic sectors globally, facing heightened risks from shifting precipitation patterns, rising temperatures, and increased frequency of extreme weather events. Adapting cultivation patterns through a climate-smart agriculture (CSA) framework—integrating productivity, adaptation, and mitigation—is critical to enhance systemic resilience and ensure food security. This study focuses on the Kosar Dam basin in western Iran, a region experiencing intensified water stress due to population growth, agricultural expansion, and recurrent droughts. Understanding the dynamic interactions between climate variability, water allocation, and farming practices in this context is essential for designing sustainable management strategies that balance ecological limits with socioeconomic needs.
 Material and methods: This research employs a system dynamics (SD) modeling approach to simulate the complex water resources system of the Kosar Dam basin over the period 2021– 2040. SD is particularly suited for capturing feedback loops, time delays, and nonlinear relationships inherent in socio-hydrological systems. Then, a multi-objective optimization algorithm is embedded within the SD framework to evaluate trade-offs among objectives such as maximizing profit, minimizing water and fertilizer consumption, and reducing greenhouse gas emissions.
Results and discussion: The analysis revealed a consistent decline in the volume of surface water throughout the study period, with an average annual reduction of -0.94%. This trend coincides with an escalating demand for water across various sectors, resulting in a growing scarcity index for water resources in the region and a diminishing water balance index. By the end of the assessment, the predicted scarcity index was 0.51, and the water balance index stood at 413 million cubic meters. These indicators suggest that the water resource situation in the basin is likely to worsen, impairing the system's ability to meet increasing national water demands. The evaluation of cropping patterns indicated an 11.5% reduction in the total cultivated area, down to 28167 hectares. Most crops exhibited a decline in cultivation, with beans being deprioritized. However, adjustments in the cultivation strategy resulted in a lower scarcity index compared to baseline conditions. Notably, the implementation of the proposed cultivation scenario achieved a 14% reduction in the average annual scarcity index.
Conclusion: This study demonstrates that integrating climate-smart agriculture principles within a system dynamics framework provides a powerful tool for navigating water–food– climate nexus challenges in semi-arid regions. Proactive, adaptive management informed by scenario modeling can significantly enhance resilience in the Kosar Dam basin and similar contexts. Key recommendations include prioritizing investments in water-saving technologies, strengthening early-warning systems for drought, and fostering participatory governance to align farmer incentives with sustainability goals.