Home > Articles > Published articles > Rice straw incorporation affects global warming potential differently in early vs late cropping seasons in southeastern China |
Date: | 2015 |
Abstract: | Paddy fields are a major global anthropogenic source of methane (CH₄) and nitrous oxide (N₂O), which are very potent greenhouse gases. China has the second largest area under rice cultivation, so developing valid and reliable methods for reducing emissions of greenhouse gases while sustaining crop productivity in paddy fields is of paramount importance. We examined the effects of applying straw, a residual product of rice cultivation containing high amounts of carbon and nutrients, to rice crops during both an early crop season (5 April - 25 July 2012) and a late crop season (1 August - 6 November 2012) on CH₄ and N₂O emissions in a subtropical paddy field in southeastern China. CH₄ fluxes had two seasonal peaks, on 5 May and 28 June, in the early crop but only one peak, on 13 August, in the late crop, which could be attributed to the lower temperatures after the final tillering stage in the late crop. Straw application significantly increased mean CH₄ cumulative production (g m־²) relative to the control in the late crop (37. 3 vs. 8. 34 mg m⁻² P < 0. 05) but not in the early crop (0. 83 vs. 01. 13 mg m⁻² P > 0. 05). The application of straw significantly increased N₂O cumulative production relative to the control in the late crop (75. 9 vs. 43. 4 μg m⁻² h⁻¹) but decreased N₂O cumulative production by over 43% in the early crop (15. 60 vs. 27. 27 μg m⁻² h⁻¹) (P < 0. 05). Straw application increased rice yield by 9. 63% and 12. 58% in early and late crop respectively. Straw incorporation decreased global warming potential in the early season, but increased it in the late season. Thus, despite straw application enhances emissions of greenhouse gases in some situations, its application in the adequate season (here early crop) may be an effective soil amendment that can increase soil fertility without enhancing or even mitigating emissions of greenhouse gases and thus climate change. |
Grants: | European Commission 610028 Ministerio de Economía y Competitividad CGL2013-48074-P Agència de Gestió d'Ajuts Universitaris i de Recerca 2014/SGR-274 |
Rights: | Aquest document està subjecte a una llicència d'ús Creative Commons. Es permet la reproducció total o parcial, la distribució, i la comunicació pública de l'obra, sempre que no sigui amb finalitats comercials, i sempre que es reconegui l'autoria de l'obra original. No es permet la creació d'obres derivades. |
Language: | Anglès |
Document: | Article ; recerca ; Versió acceptada per publicar |
Subject: | CH₄ flux ; N₂O flux ; Rice paddy ; Seasonal variation ; Straw application |
Published in: | Field crops research, Vol. 181 (Sep. 2015) , p. 42-51, ISSN 0378-4290 |
Post-print 41 p, 1015.0 KB |