Integrated agronomic practice management decreases soil carbon emission and increases environmental ecological benefits of summer maize

Abstract

Integrated agronomic practices management (IAPM) has been shown as an effective strategy to increase nitrogen use efficiency (NUE) and grain yield during crop production. A field experiment was conducted with four IAPM systems [a local smallholder farmer's practice system (T1), an improved management system (T2), a high–yield production system (T3), and an optimized management system (T4)] to study the annual yield, greenhouse gas (GHG) emissions, carbon footprint (CF), and net environmental ecological benefits (NEEB) of summer maize. The results revealed that the OMS was the optimal choice of IAPM, with increased yield and NUE and reduced GHG emissions and CF. Under OMS, the yield and NUE were 42.6% and 88.1% higher and N 2 O, CO 2 , and CH 4 emissions averaged 35.4%, 5.8%, and 156.5% lower than those of T1. The OMS had the best soil quality, the lowest soil bulk density, the highest C/N value, and the highest total organic carbon among the four treatments, which contributed to reducing GHG emissions. The CF and carbon costs were the lowest under OMS when combined with fertilizer input and GHG emissions. OMS reduced the CF and carbon cost by 5.9% and 33.9%, respectively, and increased the NEEB by 111.4% compared to T1. Although T3 had the highest yield, it had the highest GHG emissions and CF. In conclusion, the OMS achieved a high grain yield and NUE but also mitigate the negative environmental impacts, and increased NEEB, suggesting that it is a suitable management system to increase the productivity and sustainability of summer maize.