Agricultural system is the major source of greenhouse gas N2O emissions. Application of polymer-coated urea and urease and/or nitrification inhibitor has the potential in reducing soil N2O emissions, while some inconsistent results were found with the difference in N rate, climate, crops and soil properties. Researchers found that enhanced efficiency nitrogen fertiliazers were not effective in reducing N2O emissions from drip-irrigated cotton field in arid northwest China.
Researchers from Cele National Station of Observation and Research for Desert-Grassland Ecosystem, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, carried out two years cotton field experiment in Xinjiang to determine N2O emissions from different fertilizer N sources (Urea, polymer-coated urea-ESN, stabilized urea with nitrification and urease inhibitors-SuperU) and rates (120 and 240 kg N ha-1).
Results show that N2O emissions over two-year growth season were significantly increased by 29-47% in treatment of ESN or SuperU, without significant effect on cotton yield. Reducing N rate by half significantly reduced both of the N2O emissions and cotton yield.
The efficacy of ESN and SuperU is limited, fertigation with urea at recommended rate is the best option to ensure cotton yield and mitigation in N2O emission in this study site, scientists said.
Results of the study were published on Science of the Total Environment, entitled "Enhanced efficiency nitrogen fertilizers were not effective in reducing N2O emissions from a drip-irrigated cotton field in arid region of Northwestern China".
Article link: https://www.sciencedirect.com/science/article/abs/pii/S0048969720350725.
Contact: LIU Jie, Xinjiang Institute of Ecology and Geography