Abstract:
Objectives The systematic investigations on the change of nitrogen use efficiency, nitrogen balance, and carbon emissions of winter wheat in a typical fluvo-aquic soil under different nitrogen fertilizer management practices benefits to understand the potential nutrient use efficiency improved and carbon sequestrated, and further promotes the green sustainable development of winter wheat in north China plain.
Methods A field experiment was conducted in Yuanyang County, Henan Province, in a typical fluvo-aquic soil in the North China Plain using winter wheat as the test crop. Four treatments were established: no nitrogen fertilizer (CK), farmer practice fertilization (FP), optimized fertilization (NE), and combined organic-inorganic fertilization (MNPK). The effects of different nitrogen management strategies on yield, nirogen use efficiency, soil nitrogen balance and carbon footprint were evaluated during the 2024−2025 winter season.
Results Compared with the FP treatment, the MNPK treatment significantly increased the 2-years average winter wheat yield by 1388.3 kg/hm2, representing increases of 14.1% (P<0.05). The NE treatment increased the average economic benefit by 847.5 yuan/hm2 (a rise of 3.8%), whereas the MNPK treatment reduced it by 10584.9 yuan/hm2 (a reduction of 47.3%). Compared with the FP treatment, over the 2 years average nitrogen recovery efficiency under the NE and MNPK treatments significantly increased by 27.8% and 36.9%, respectively (P<0.05). Agronomic efficiency significantly increased by 52.6% and 137.0%, and partial factor productivity significantly increased by 46.6% and 97.9%, respectively. The DNDC simulation results indicated that the MNPK treatment exhibited the significantly lowest Net global warming potential (Net GWP) among all the treatments. Compared to the FP and NE treatments, the MNPK treatment decreased the 2 year average Net GWP by 86.5% and 68.5%, respectively; and reduced the carbon footprint (CF) by 43.1% and 18.1%, respectively.
Conclusions In winter wheat production in the Huang-Huai-Hai Plain, optimized nitrogen management in chemical fertilizers when combined with organic fertilizers can improve nitrogen use efficiency, and reduce carbon emissions. Therefore, to further promote the combined application of organic and chemical fertilizers, it is necessary to reduce the cost of organic fertilizer and increase the economic returns of crops, thereby promoting sustainable farmland utilization.