Emergy analysis-based research on sustainable development of corn planting ecosystems in Sichuan Province

Introduction Sichuan province serves as a vital grain production hub in southwestern China, where corn planting industry plays a critical role in maintaining regional food security. Understanding the sustainability of corn production ecosystems is essential for optimizing agricultural resource allocation and ensuring long-term food security in this economically important region. Methods This study employed an emergy analysis framework to assess the sustainability of Sichuan’s corn planting ecosystems in 2022. An evaluation system comprising 18 indicators was developed, encompassing natural resource emergy, industrial support energy, and purchased renewable resources. Moving weighted trend surface analysis was applied to identify spatial patterns in environmental sustainability, while partial least squares discriminant analysis was used to categorize regions and identify key driving factors of regional differences. Results The analysis revealed significant regional disparities across multiple dimensions. In terms of emergy input and output, Chengdu city exhibited the highest emergy input density 10.59 × 10 11 sej·m −2 , nearly double that of Garzê Tibetan Autonomous Prefecture (5.36 × 10 11 sej·m −2 ), while Aba Tibetan and Qiang Autonomous Prefecture showed the lowest emergy output density, reaching only 40% of Dazhou city’s levels. Regarding investment benefits, Chengdu city maintained the highest emergy investment ratio (4.13) but demonstrated the lowest net emergy yield ratio (1.17), contrasting with Ziyang city’s highest net emergy yield ratio (2.07). Management and environmental impact assessments revealed substantial regional variations, with Suining city achieving the highest scale management degree (59.8) compared to mountainous regions averaging only 21.64. Environmental loading ratios remained below 1 in 67% of regions, while high-level areas averaged 1.71, indicating significant ecological pressure. Spatial analysis demonstrated a northeast-to-southwest declining pattern in environmental sustainability index ( R 2 = 0.63, p < 0.05). Four distinct regional groups were identified, with net emergy yield ratio, emergy output density, and scale management degree emerging as the three key factors driving regional differences. Discussion These findings reveal the combined influence of natural resource availability and human energy inputs on agricultural sustainability across Sichuan province. The significant regional imbalances in resource input and output efficiency, coupled with obvious topographical influences on management practices, highlight the need for differentiated agricultural development strategies. The identification of key driving factors provides a scientific foundation for formulating regionally targeted policies to optimize resource allocation and enhance the overall sustainability of corn production systems in southwestern China.