Trade-offs between grain yields and ecological efficiencies in a wheat-maize cropping system using optimized tillage and fertilization management on the North China Plain.

Optimized fertilizer and tillage management can be an effective strategy for high ecological efficiencies as well as crop yields. The objective of this study was to assess the impact of diverse management practices on carbon footprint, and ecosystem services in a wheat-maize cropping system. An in situ field experiment field was conducted from 2018 to 2020 on the North China Plain, and six treatments were established: deep tillage (DT), shallow tillage (ST), no tillage (NT), deep tillage + adding organic fertilizer (DTF), shallow tillage + adding organic fertilizer (STF), and no tillage + adding organic fertilizer (NTF). The results showed that adding organic fertilizer and the deeper tillage depth caused higher direct CO2 and N2O emission fluxes. DTF treatment significantly increased carbon footprint either per-unit area (CFa) or per-unit net income (CFe). Compared with DT treatment, STF treatment had higher CFa but lower CFe by increasing net income through boosted crop yields. Besides, the highest ecosystem service values (ESV) were present in STF treatment during both 2 years (42,017.13 CNY ha-1 and 43,352.03 CNY ha-1). In conclusion, STF treatment was an optimal management practice to trade-off grain yields and ecological efficiencies in a wheat-maize cropping system. Furthermore, this study highlights that adding organic fertilizer could be an efficient option toward sustainable farmland utilization with high soil carbon sequestration capacity and high ESV.