Influence of rice mechanical planting methods on methane and nitrous oxide emissions from paddy field

Methane (CH[sub 4]) and nitrous oxide (N[sub 2]O) are 2 important long-lived greenhouse gases (GHGs) that contribute to global warming. Paddy soils have been identified as a dominant source of atmospheric CH[sub 4] and N[sub 2]O. Little information is available on the impacts of rice mechanical planting methods on CH[sub 4] and N[sub 2]O emissions and rice yield in high production rice-wheat double cropping system. A field experiment was conducted with super rice cultivar Nanjing 44 as materials during the rice growing season from 2011 to 2012 in Suzhou, Jiangsu Province. By using static chamber/gas chromatographic techniques, in this two-year field experiment CH[sub 4] and N[sub 2]O emissions were simultaneously measured under 3 rice planting methods: mechanical direct-seeding (MD), mechanical transplanting (MT) and artificial transplanting (AT). The results indicated that all treatments exhibited comparable seasonality in CH[sub 4] fluxes, showing an increase at the beginning and a decline later on.