Chinese Journal of Agrometeorology ›› 2014, Vol. 35 ›› Issue (02): 141-148.doi: 10.3969/j.issn.1000-6362.2014.02.004

• 论文 • Previous Articles     Next Articles

Study on the Pathway and Dynamics of N2O Emissions From the Vegetable Soil Fertilized With Ammonium Nitrogen

YAN Hongliang,ZHANG Xuan,XIE Liyong,HE Cuicui,REN Huanyu,ZHANG He,FAN Jingwei,LIN Miao ,GUO Liping   

  1. 1Institute of Environment and Sustainable Development in Agriculture,CAAS/Key Laboratory of Agricultural Environment,MOA,Beijing 100081,China;2College of Agronomy,Shenyang Agricultural University,Shenyang110866;3Institute of Agricultural Resources and Regional Planning,CAAS;4College of Forestry,Shanxi Agricultural University,Taigu030801
  • Received:2013-10-14 Online:2014-04-20 Published:2015-02-11

Abstract: Nitrous oxide is one of the most important greenhouse gases emitted from fertilized agricultural soils.Vegetable soil may contribute great share to the national N2O emissions due to the higher fertilization rate,multiple application and irrigation This experiment aimed to investigate the contributions of various N2O production processes after ammonium nitrogen was applied during three weeks laboratory incubation period under 70% field water capacity in a vegetable soil We used the different gas inhibitors to distinguish the different N2O production processes The treatments include no gas inhibitor (CK),0.06% acetylene (A),pure oxygen (O),0.06% acetylene plus pure oxygen (AO),pure helium(H)Based on the processes occurred or inhibited under different gas inhibitor treatments,N2O fluxes and its contribution and dynamics from autotrophic nitrification,nitrifier denitrofication and denitrification were calculated and analyzed during the incubation periodThe results showed that N2O fluxes were peaked at 314.4ngg-1d-1within the 48h after fertilization,and then rapidly decreased to 1/6 of that by the 4th day followed by more decreased quantity with the increase of incubation time Autotrophic nitrification contributing more than 50% and 40% of total N2O fluxes within two weeks and thereafter respectively,was the main source of N2O emissions after ammonium nitrogen was applied. Nitrifier denitrification contributed greatly (up to 44%) to the total N2O emission fluxes within 2days after fertilization and about 14%-27% thereafter Although the contribution of denitrification on total N2O emission fluxes were increased from 1%within the first 2 days period to about 30% after two weeks later with the decrease of soil ammonium and increase of soil nitrate,its substantial contribution on N2O fluxes were still less due to the lower absolute N2O flux quantities (about 1/20 of that within the first 2 days) two weeks later N2O production and its sources were associated with the content and dynamics of soil ammonium and nitrate Soil pH showed decrease after ammonium nitrogen application. Therefore,control the speed of nitrification is a better option to decrease the N2O emissions in the vegetable soils fertilized with ammonium nitrogen

Key words: N2O, Vegetable soil, Ammonium fertilizer, Greenhouse gas, Nitrification