Unveiling the impact of mulching film promotion on the food–water–environment–plastic nexus

•Plastic mulching film (PMF), as an effective measure of increasing agricultural yields worldwide, leads to negative effects on resources and environment.•Food–Water–Environment–Plastic nexus effect analysis model is constructed to evaluate the PMF comprehensive effects.•PMF will increase the national average maize yield and address food security for 267.65 million people.•PMF promotion can expand China's maize belt from east to west while exacerbating the water gap in different regions.•Through the implementation of the optimal promotion mode, PMF can facilitate sustainable food production with minimal environmental costs. Plastic mulching film (PMF) enhances grain yields, while leading to negative effects on water depletion, environmental impact, and plastic residues if not properly controlled. By constructing a Food–Water–Environment–Plastic nexus effect analysis model jointly utilizing the WOFOST model, mixed regression, and life cycle assessment, we evaluate the comprehensive effect of PMF promotion in Chinese maize cultivation. 35 cross-cutting scenarios are analyzed to identify the optimal PMF promotion mode and corresponding policy recommendations are given. The results show that PMF will increase China’s maize yield, securing food for an additional 267.65 million people in 2050. PMF promotion will aid high-altitude and drought-prone regions to overcome yield constraints, expanding China’s maize belt westward. However, promotion will exacerbate regional water supply-demand imbalances in northern and southern China and form a “T-shaped” PMF residue belt. In the optimal scenario, China will increase yield by 48.52 million tonnes, reducing resource and environmental impacts by over 60 % in 2050. [Display omitted]