Abstract:
China is confronting trade-offs and the need for harmonization between food security and environmental sustainability. It is crucial to assess changes in the sustainability of crop production from multiple perspectives and evaluate the effectiveness of policy implementation. This study, based on the provincial administrative region scale, focuses on four key environmental indicators of crop production systems in China: water consumption for irrigation, excess use of nitrogen and phosphorus, and greenhouse gas (GHG) emissions. We integrated data from various sources, including remote sensing, statistical surveys, and model simulations. Using methods such as mass balance modeling, simulations, and emission inventories, we evaluated the spatiotemporal dynamics of crop production's environmental impacts at the provincial level in China from 2010 to 2020. This approach enables the quantification of water resource stress, non-point source pollution, and climate change impacts associated with crop production. The results indicate that from 2010 to 2020, crop production in joules increased by 23%, accompanied by a 15% rise in irrigation water usage. However, nitrogen and phosphorus surpluses decreased by 14% and 15%, respectively, while GHG emissions declined by 8%. Environmental indicators in most regions demonstrated significant improvement, reflecting a positive trend toward sustainable development. However, the total environmental indicators in Xinjiang, Gansu, Ningxia, and Shaanxi provinces still exhibited an increasing trend. Notably, the intensity of these environmental indicators per GJ yield has decreased, and the comprehensive environmental impact has declined by 14%. Regional analysis revealed that the integrated environmental impact significantly decreased in Northeast China, the Huang-Huai-Hai region, and parts of Southwest China. In contrast, Xinjiang, Jiangxi, Fujian, Guangdong, and Hainan provinces consistently faced increasing environmental pressures. Despite the overall environmental impact of crop production showing a mitigation trend, the notable regional differences in environmental impact highlight the complexity of localized environmental pressures. Based on the research conclusions, we propose several policy recommendations that are conducive to balancing food security and environmental sustainability. These include identifying key provincial administrative regions and environmental indicators for prioritizing environmental governance and avoiding land cultivation in ecologically fragile hotspots with high environmental impact intensity. This study can provide references for identifying priority actions to mitigate the environmental impacts of crop production and for developing regionally differentiated policies aimed at sustainable agricultural development. It will also assist various regions in formulating specific policies to minimize environmental impacts while maintaining crop production.