Humic acid urea improved grain yield and farmer’s profits while mitigating the carbon footprint of wheat production

Enhancing crop yield and reducing active nitrogen (N) loss are crucial for the efficient utilization of N fertilizer and the decrease of agricultural greenhouse gas (GHG) emissions. Humic acid urea (HAU), an efficient N fertilizer produced via in-situ incorporating small amounts of humic acid into urea production, has reached to 1 Tg of physical quantity of annual production in China for its efficiency enhanced via the comprehensive regulation on fertilizer-crop-soil systems. Therefore, we hypothesized that HAU would increase yield and reduce the carbon footprint relative to CU, and tested it in a winter wheat experiment at two N rates (225 and 180 kg ha⁻ 1 ) in the North China Plain. The results showed that the application of HAU resulted in a significantly higher grain yield by 7.0–23.3% than CU, and thus significantly increased farmer’s profits by 8.8–29.8%. HAU production resulted in more GHG emission than CU production by 6.9 kg CO 2 -eq Mg −1 ; however, the GHG emission from the field was significantly reduced (10.1–23.3%) by reducing gaseous N loss. In the whole life cycle, HAU resulted in lower GHG emissions (1.9–14.4%) in the winter wheat agroecosystem. HAU application also contributed to higher C fixation and ecosystem economic benefit. HAU at 180 kg ha −1 achieved a comparable yield and farmer’s profit with CU at 225 kg N ha −1 , while reduced GHG emission by 14.4%. Applicating HAU is an advantageous N management strategy for maintaining wheat yield with the lowest C footprint.