Soil nitrous oxide emissions under dryland N-fertilised canola and N2-fixing chickpea in the northern grains region, Australia.

摘要: Nitrous oxide (N 2O) emissions from cropping soils contribute to increasing atmospheric N 2O. Planning reduce requires real-world measurements. Crop production systems that partially rely on nitrogen (N) fixed by legumes may emit less 2O than are totally dependent fertiliser inputs. We measured a dryland vertosol in northwest NSW, Australia during the growth of Nfertilised canola ( Brassica napus ) and 2-fixing chickpea Cicer arietinum ). At sowing, received 80 kg N/ha as urea, was inoculated with effective rhizobia. Emissions were monitored seven times per day using an automated system chambers connected gas chromatograph. Daily ranged -1.7 39.6 g 2O-N/ha/day plots -1.6 12.5 for chickpea. During crop growth, N-fertilised emitted total 293 2O-N/ha, equivalent 0.37% urea applied. Chickpea 29 2O-N/ha. The further 241 N2O-N/ha first months post-crop fallow, mostly short period high rainfall, compared 58 2O-N/ha hypothesise residue have mineralised earlier chickpeas.