Carbon and Nitrogen Footprints of Major Corn Production Systems in China

Jianya Zhao^1,2Fanhao Yang^1,2Yanglan Zhang^2,3Shu Wang^2,3*

• ¹Jinan University University of Birmingham Joint Institute, Guangzhou, China
• ²Jinan University, Guangzhou, China
• ³School of Economics, Jinan University, Guangzhou, China

In the context of global climate warming and agricultural carbon emission management, corn, as the most widely cultivated and highest-yielding cereal crop in China, plays a crucial role in ensuring food security and supporting the development of the livestock industry. Its production process not only generates substantial carbon emissions but also significantly affects the nitrogen cycle in the environment, closely relating to the stability of ecosystems. To address existing gaps in nationwide systematic analysis, ambiguous regional delineation, and insufficient reflection of policy dynamics, calculating the carbon and nitrogen footprints of corn production in China and formulating corresponding emission reduction strategies are of great significance. Based on agricultural input statistical data from 2014 to 2023, this study divides different major corn production areas according to policy planning and humidity zones. It employs the full life cycle method and area-weighted method to calculate the carbon and nitrogen footprints per unit area for different corn production regions and analyzes the impact of factors such as planting area expansion, fertilizer reduction, and pesticide reduction on carbon emissions through scenario simulations. The results indicate the following: (1) The Northwestern Irrigated Corn Region (based on government's corn regional planning), arid, and semi-arid regions (based on humidity zones) have higher carbon footprints, while the Northwestern Irrigated Corn Region and arid areas have the highest nitrogen footprints. (2) Scenario simulations show that planting area expansion serves as a baseline for the carbon and nitrogen footprints per unit area. The impact of fertilizer and pesticide reduction on the carbon footprint varies depending on regional characteristics, while fertilizer reduction-especially nitrogen fertilizer-has a notably greater effect on reducing the nitrogen footprint. It provides scientific evidence and policy approaches for balancing food security with low-carbon transformation and nitrogen management in key corn production areas, thereby contributing to achieving agricultural carbon neutrality and improving agricultural nitrogen cycling.