Spatial heterogeneity of greenhouse gas emissions from cereal crop production in China

China is a major producer of wheat, maize and rice, which generates massive greenhouse gas emissions due to the consumption of elevated amounts of energy, land, and water, yet there is actually few knowledge on the spatial heterogeneity of greenhouse gas emissions. Here, we introduce a polyphasic approach to quantify the emissions from the land, energy, and water in Chinese cereal production. Results show that total greenhouse gas emissions from wheat, maize and rice crops reached 505.5 Tg CO(2)eq, including 247.5 Tg CO(2)eq for the land, 222.1 Tg CO(2)eq for energy, and 35.9 Tg CO(2)eq for water. The major greenhouse gas contributors are the land, of 55.8%, and energy to produce nitrogen fertilizers, of 30.5%. Moreover, greenhouse gas emissions from cereal production show large-scale spatial heterogeneity at the provincial scale due to differences in crop type, natural resources, and managerial practices. The collective adoption of green technologies and reasonable food trading practices could reduce greenhouse gas emissions from the cereal production supply chain, further promoting the carbon neutrality of agriculture.

Automated summary

China is a major producer of wheat, maize, and rice, but the production of these crops results in significant greenhouse gas emissions. In this study, we utilized a comprehensive approach to quantify the emissions from land, energy, and water in the cereal production of China. The results showed that the total greenhouse gas emissions from wheat, maize, and rice crops reached 505.5 Tg CO(2)eq, with land and energy being the major contributors. Additionally, there was significant spatial heterogeneity in greenhouse gas emissions at the provincial level, attributed to variations in crop type, natural resources, and management practices. The adoption of green technologies and sustainable food trade practices could effectively reduce greenhouse gas emissions and promote carbon neutrality in agriculture.