Quantifying synergistic evolution of water-energy-food systems under multidimensional stressors: A system dynamics approach in ecologically fragile grain base

Against the backdrop of intensifying global climate change and escalating anthropogenic pressures, investigating the water-energy-food (WEF) nexus is critical for advancing sustainable development in ecologically fragile regions and major grain-producing areas. Taking the western Jilin Province, China as the study area, this research innovatively constructs a multi-dimensional system dynamics model and designs scenarios including the baseline scenario, climate change scenario, energy technology advancement scenario, and agricultural policy change scenario. It explores the interaction mechanisms and evolutionary processes of the WEF system in regions characterized by both ecological fragility and high grain yield. Findings reveal that under the baseline scenario, the key indicators of the WEF system in western Jilin Province exhibit the characteristics of "the highest grain output, the highest total water consumption, and moderate energy consumption", with a close interconnection between the water and grain subsystems. External interventions exert significantly different impacts on the WEF system. Among them, climate change has the most prominent impact on the grain and water resource subsystems; in the energy technology advancement scenario, the development of low-water-consumption new energy has a positive effect on the water resource subsystem, but at the same time, it causes certain negative impacts on grain output due to the occupation of cultivated land; the agricultural policy change scenario, centered on the adjustment of the planting structure of corn and soybeans, presents a "triple decline" pattern featuring reductions in grain output, total water consumption, and energy consumption. Based on the simulation results, this paper puts forward multi-dimensional strategic suggestions from aspects such as water resource management, land use coordination, and policy innovation, aiming to promote the coordinated and sustainable development of the regional WEF system. • Scientific simulation of WEF Nexus dynamics under combined natural and socio-economic factors. • Verified the close and tense relationship between water and food in ecologically vulnerable grain-producing regions. • Drought most significantly impacted the WEF Nexus among studied external forces. • Proposed suggestions to promote the coordinated development of WEF Nexus.