02296naa a2200265 a 450000100080000000500110000800800410001902200140006002400410007410000160011524501250013126000090025652015220026565000210178765000150180865000090182365300220183265300260185465300160188065300210189670000200191770000220193770000200195977300510197921469592022-09-28       2022    bl uuuu     u00u1 u    #d  a1838-675X7 ahttps://doi.org/10.1071/SR210942DOI1 aALVAREZ, C.  aSoil nitrous oxide emissions in a maize (Zea mays L.) crop in response to nitrogen fertilisation.h[electronic resource]  c2022  aContext: An appropriate use of the fertiliser technology may lead to a more efficient N absorption and to the reduction of economic and environmental costs. Aims: This study sought to quantify N2O emissions generated from soil and the residual nitrate (NO3?) up to 2 m depth in field conditions in a maize crop under supplementary irrigation and fertilised with two nitrogen (N) sources (UAN and urea) at increasing N rates (0, 80, 160 and 250 kg N ha?1) in the Semi-arid Argentine Pampas. Methods: Throughout the crop cycle, emissions were monitored daily with static chambers during the first week after fertilisation; then sampling frequency was gradually reduced until the end of the experiment. Key results: There were no yield responses to the use of different sources and N rates. Crop N uptake saturated at 80 kg N ha?1, reaching 300?310 kg N ha?1. Residual NO3? increased significantly with the highest rates of N fertiliser. Total N2O emissions differed significantly only among fertiliser rates. The N2O emissions were lower at 80 than at 160 and 250 kg N ha?1. Conclusions: The N2O emissions measured were lower than those calculated by the IPCC, even when only direct emissions were considered. No grain yield increase was observed due to N fertilisation, with a non-limiting supply of N-NO3? at the beginning of the crop cycle and of N from mineralisation. Implications: This excess of N can generate negative environmental effects due to higher emissions of N2O and residual N-NO3? that can be leached.  aGreenhouse gases  aIrrigation  aUrea  aArgentinean Pampa  aEnvironmental effects  aMaize yield  aNitrate leaching1 aÁLVAREZ, C. R.1 aCOSTANTINI, A. O.1 aALVES, B. J. R.  tSoil Research, Published online: 13 June 2022.