Straw Incorporation Mitigating Fertiliser‐Induced Nitrous Oxide Emissions in Intensively Managed Protected Vegetable Soils

ABSTRACT The impact of straw incorporation on nitrous oxide (N 2 O) emissions has long been a research focus. However, N 2 O emissions from protected vegetable soils with straw incorporation and their response to increased nitrogen (N) input are not well understood. To address this knowledge gap, greenhouse vegetable soils with and without 6‐year straw incorporation were studied in a laboratory experiment with aerobic incubations. Urea‐N solutions were applied to achieve contents of 0, 20, 40, 80, and 120 mg urea‐N kg −1 soil. Soil N 2 O, carbon dioxide (CO 2 ) and oxygen (O 2 ) dynamics were monitored using a robotized incubation system, while contents of ammonium (), nitrite (), and nitrate () were measured. Straw incorporation significantly reduced and contents and decreased N 2 O emission fluxes. Cumulative N 2 O emissions increased exponentially with rising urea‐N rates, but straw significantly lowered mean cumulative N 2 O emissions and fertiliser‐induced N 2 O emission factors at all urea‐N rates. Cumulative CO 2 emissions increased linearly with urea‐N rates, and straw incorporation significantly elevated average CO 2 fluxes, regardless of urea‐N addition. Straw incorporation also accelerated O 2 depletion across all urea‐N rates. Soil content emerged as the most important predictor of N 2 O emission fluxes, irrespective of straw incorporation. The findings show that straw incorporation decreases and accumulation and mitigates fertiliser‐induced N 2 O emissions in intensively managed protected vegetable soils. This study provides a sustainable agricultural management approach that balances soil fertility enhancement with greenhouse gas emission reduction.