Carbon Footprint of Main Grain Crop Production in Hubei and Jiangsu Provinces, 2005–2019

Hubei and Jiangsu Provinces, significant in grain production, play a crucial role in national food security. We studied the carbon footprint of main grain crops (rice, maize, and wheat) from 2005 to 2019 in these provinces to identify trends, contributing factors, and emission efficiencies. This study seeks to inform sustainable agricultural practices and policies in the context of climate change mitigation. Jiangsu Province’s rice and wheat output surpasses Hubei’s due to higher yields per unit area. Rice consistently shows the highest carbon footprint per unit area, followed by wheat, with maize exhibiting the lowest. Carbon footprint per unit yield varies significantly: for rice, it ranges from 0.15 to 0.29 kg CO 2 -eq per kg; for wheat, from 0.19 to 0.22 kg CO 2 -eq per kg; and for maize, from 0.13 to 0.15 kg CO 2 -eq per kg. The distribution of crop production affects these footprints; central regions generally exhibit lower values compared to southwest and southeast areas. Fertilizer and electricity together contribute significantly to carbon emissions, especially in rice production (over 75%), and to a lesser extent in maize and wheat production (approximately 69% and 85%, respectively). Improving fertilizer efficiency, irrigation, and mechanization is crucial for developing low-carbon agriculture in these pivotal grain-producing regions.