Nitrite stimulates HONO and NOx but not N2O emissions in Chinese agricultural soils during nitrification

作者：Song, Yaqi; Wu, Dianming^*; Ju, Xiaotang; Dorsch, Peter; Wang, Ruhai; Song, Xiaotong; Deng, Lingling; Wang, Rui; Gao, Zhiwei; Haider, Haroon; Hou, Lijun; Liu, Min; Yu, Yuanchun^*; Wang, Mengdi

来源：Science of the Total Environment, 2023, 902: 166451.

DOI：10.1016/j.scitotenv.2023.166451

• Nitrogen cycle
• Nitrification inhibitor
• Climate warming
• Air pollution
• Acidic soil
• Reactive nitrogen

The long-lived greenhouse gas nitrous oxide (N2O) and short-lived reactive nitrogen (Nr) gases such as ammonia (NH3), nitrous acid (HONO), and nitrogen oxides (NOx) are produced and emitted from fertilized soils and play a critical role for climate warming and air quality. However, only few studies have quantified the production and emission potentials for long-and short-lived gaseous nitrogen (N) species simultaneously in agricultural soils. To link the gaseous N species to intermediate N compounds [ammonium (NH4+), hydroxylamine (NH2OH), and nitrite (NO2  )] and estimate their temperature change potential, ex-situ dry-out experiments were conducted with three Chinese agricultural soils. We found that HONO and NOx (NO + NO2) emissions mainly depend on NO2 , while NH3 and N2O emissions are stimulated by NH4+ and NH2OH, respectively. Addition of 3,4-dimethylpyrazole phosphate (DMPP) and acetylene significantly reduced HONO and NOx emissions, while NH3 emissions were significantly enhanced in an alkaline Fluvo-aquic soil. These results suggested that ammonia-oxidizing bacteria (AOB) and complete ammonia-oxidizing bacteria (comammox Nitrospira) dominate HONO and NOx emissions in the alkaline Fluvo-aquic soil, while ammonia-oxidizing archaea (AOA) are dominant in the acidic Mollisol. DMPP effectively mitigated the warming effect in the Fluvo-aquic soil and the Ultisol. In conclusion, our findings highlight NO2  significantly stimulates HONO and NOx emissions from dryland agricultural soils, dominated by nitrification. In addition, subtle differences of soil NH3, N2O, HONO, and NOx emissions indicated different N turnover processes, and should be considered in biogeochemical and atmospheric chemistry models.

• 单位
  中国科学院; 海南大学; 南京林业大学