Articles | Volume 12, issue 3
Biogeosciences, 12, 803–815, 2015
Biogeosciences, 12, 803–815, 2015

Research article 10 Feb 2015

Research article | 10 Feb 2015

Nitrous oxide emission and nitrogen use efficiency in response to nitrophosphate, N-(n-butyl) thiophosphoric triamide and dicyandiamide of a wheat cultivated soil under sub-humid monsoon conditions

W. X. Ding1, Z. M. Chen1, H. Y. Yu1, J. F. Luo2, G. Y. Yoo3, J. Xiang1, H. J. Zhang1, and J. J. Yuan1 W. X. Ding et al.
  • 1State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China
  • 2Land and Environment, AgResearch, Hamilton 3240, New Zealand
  • 3College of Engineering, Kyung Hee University, Yongin-si 446-701, South Korea

Abstract. A field experiment was designed to study the effects of nitrogen (N) source and urease inhibitor N-(n-butyl) thiophosphoric triamide (NBPT) or nitrification inhibitor dicyandiamide (DCD) on nitrous oxide (N2O) emission and N use efficiency (NUE) in a sandy loam soil. Six treatments including no N fertilizer (control), N fertilizer urea alone (U), urea plus NBPT (NBPT), urea plus DCD (DCD), urea plus NBPT and DCD (NBPT plus DCD) and nitrate-based fertilizer nitrophosphate (NP) were designed and implemented separately during the wheat growth period. Seasonal cumulative N2O emissions with urea alone amounted to 0.49 ± 0.12 kg N2O-N ha−1 and were significantly (P < 0.05) reduced to 0.28 ± 0.03, 0.31 ± 0.01 and 0.26 ± 0.01 kg N2O-N ha−1 by application of DCD, NBPT and NBPT plus DCD, respectively. Cumulative N2O emissions from NP were 0.28 ± 0.01 kg N2O-N ha−1. A single N2O flux peak was identified following basal fertilization, and DCD and/or NBPT inhibition effects mainly occurred during the peak emission period. The NP application significantly (P < 0.05) increased wheat yield by 12.3% and NUE from 28.8% (urea alone) to 35.9%, while urease and/or nitrification inhibitors showed a slight increase effect. Our results clearly indicated that the application of urea as basal fertilizer, but not as supplemental fertilizer, together with DCD and NBPT is an effective practice to reduce N2O emissions. The application of NP instead of urea would be an optimum agricultural strategy for reducing N2O emissions and increasing crop yield and NUE for wheat cultivation in soils of the North China Plain.

Short summary
The combination of NBPT and DCD with basal rather than supplemental fertilizer urea would be an effective practice for reducing N2O emission during the wheat growth season. Additionally, application of nitrophosphate, instead of urea, is an optimum agricultural strategy for reducing N2O emission and for increasing crop yield and nitrogen use efficiency for wheat cultivation in the soils of the North China Plain.
Final-revised paper