The application of nitrification inhibitors(NIs)and crop straw with nitrogen(N)fertilizers is a common practice aimed at enhancing soil N conservation and improving crop N use.However,their effects on gaseous N emissi...The application of nitrification inhibitors(NIs)and crop straw with nitrogen(N)fertilizers is a common practice aimed at enhancing soil N conservation and improving crop N use.However,their effects on gaseous N emissions from soils,particularly for N_(2),are less understood.We conducted a 60-day soil incubation experiment under controlled conditions(80%water-filled pore space and 25℃)to investigate the effects of NI or maize straw application on N_(2)O and N_(2)emissions from two typical upland soils:a Mollisol and an Inceptisol,which have contrasting pH values.Both soils were fertilized with^(15)N-labeled urea.During the incubation period,cumulative N_(2)O and N_(2)emissions for the urea-only treatment in the Mollisol were 0.5 and 12 mg N kg^(‒1)soil,respectively,while emissions in the Inceptisol reached 15 and 176 mg N kg^(‒1).The application of NI(dicyandiamide)reduced N_(2)O emissions by 66%‒72%in both soils and decreased N_(2)emissions by 81%in the Inceptisol,although it increased N_(2)emissions by 15%in the Mollisol.Straw application also reduced N_(2)O emissions by 60%in the Mollisol and by 4%in the Inceptisol,but it increased N_(2)emissions by 75%‒96%in both soils.Notably,the increased N_(2)emissions following straw incorporation were primarily soil-derived rather than fertilizer-derived in both soils.These findings reveal that the applications of NIs or straw have varying impacts on N_(2)O and N_(2)emissions across different soils,and that NI application could be a promising strategy to reduce high gaseous N losses in Inceptisol following N fertilization.展开更多
基金supported by the National Key Research and Development Program of China(Grant Nos.2023YFD1501400 and 2023YFD1500802)the Strategic Priority Research Program of the Chinese Academy of Sciences(Grant No.XDA28020302)+5 种基金the National Natural Science Foundation of China(Grant Nos.42177214 and 41701309)the Shandong Provincial Natural Science Foundation(Grant No.ZR2023YQ030)the Liaoning Vitalization Talents Program(Grant Nos.XLYC2203058 and XLYC1902016)Shenyang Science and Technology Talent Program(Grant No.RC230102),and the Taishan Scholars(Grant No.202211306)We also acknowledge support from the K.C.Wong Education Foundation(Y.F.)the Youth Innovation Promotion Association CAS(Z.Q).
文摘The application of nitrification inhibitors(NIs)and crop straw with nitrogen(N)fertilizers is a common practice aimed at enhancing soil N conservation and improving crop N use.However,their effects on gaseous N emissions from soils,particularly for N_(2),are less understood.We conducted a 60-day soil incubation experiment under controlled conditions(80%water-filled pore space and 25℃)to investigate the effects of NI or maize straw application on N_(2)O and N_(2)emissions from two typical upland soils:a Mollisol and an Inceptisol,which have contrasting pH values.Both soils were fertilized with^(15)N-labeled urea.During the incubation period,cumulative N_(2)O and N_(2)emissions for the urea-only treatment in the Mollisol were 0.5 and 12 mg N kg^(‒1)soil,respectively,while emissions in the Inceptisol reached 15 and 176 mg N kg^(‒1).The application of NI(dicyandiamide)reduced N_(2)O emissions by 66%‒72%in both soils and decreased N_(2)emissions by 81%in the Inceptisol,although it increased N_(2)emissions by 15%in the Mollisol.Straw application also reduced N_(2)O emissions by 60%in the Mollisol and by 4%in the Inceptisol,but it increased N_(2)emissions by 75%‒96%in both soils.Notably,the increased N_(2)emissions following straw incorporation were primarily soil-derived rather than fertilizer-derived in both soils.These findings reveal that the applications of NIs or straw have varying impacts on N_(2)O and N_(2)emissions across different soils,and that NI application could be a promising strategy to reduce high gaseous N losses in Inceptisol following N fertilization.
