Potato intercropping with soybean increased soil N2O emissions, but was alleviated by nitrogen-enhanced-efficiency techniques

While intercropping improves the utilisation of spatiotemporal resources, facilitates the absorption of soil nutrients, and augments crop yield, complex rhizospheric interactions in non-cereal/legume systems can stimulate N 2 O emissions. This study investigated this trade-off in a potato/soybean system and tested potential mitigation strategies through two pot experiments. Our results confirmed that potato/soybean intercropping significantly increased N 2 O emissions by 35.70 % and 19.04 % compared to potato and soybean monocultures, respectively. This effect was attributed to rhizosphere interactions, as proven by lower emissions under a root-segregation treatment. Soil NH 4 + -N, NO 2 - -N, and water-filled pore space (WFPS) were positively correlated with N 2 O emission. A second experiment demonstrated that while microbial consortium inoculation was beneficial for reducing N₂O, the nitrification inhibitor, 3,4-dimethylpyrazole succinic acid (DMPSA), was most effective, simultaneously reducing nitric oxide (NO) and N₂O emissions by 92.78 % and 60.77 %, respectively. In conclusion, while the increase in N 2 O emissions under potato/soybean can undermine its ecological benefits, this trade-off can be successfully managed. Adopting nitrification inhibitors or microbial consortium inoculation with the capacity to reduce N 2 O emissions is a potent strategy to minimise reactive N losses and improve N management in conservation agriculture. • Potato/soybean intercropping significantly stimulated N 2 O emission. • Rhizobium inoculation increased N 2 O emission of soybean monoculture. • Microbial consortia inoculation mitigated N 2 O emission. • Nitrification inhibitor effectively alleviated both NO and N 2 O emissions.