Impacts of cropping practices on yield-scaled greenhouse gas emissions from rice fields in China: A meta-analysis

• Published in: Agriculture, ecosystems & environment ecosystems & environment, 2013-01, Vol.164, p.220-228
• Main Authors: Feng, Jinfei, Chen, Changqing, Zhang, Yi, Song, Zhenwei, Deng, Aixing, Zheng, Chengyan, Zhang, Weijian
• Format: Article
• Language: English
• Subjects: Agronomy. Soil science and plant productions; Air pollution; Assessments; Biological and medical sciences; Carbon dioxide; CH4; China; Emission analysis; Emissions control; Food security; Fundamental and applied biological sciences. Psychology; General agroecology; General agroecology. Agricultural and farming systems. Agricultural development. Rural area planning. Landscaping; General agronomy. Plant production; Generalities. Agricultural and farming systems. Agricultural development; Global warming; Greenhouse effect; Human physiology applied to population studies and life conditions. Human ecophysiology; Magnesium; Medical sciences; N2O; Nutritional survey. Food supply and nutritional requirement; Oryza sativa; Reduction; Rice; Rice cropping
• ISSN: 0167-8809; 1873-2305
• DOI: 10.1016/j.agee.2012.10.009

► We assessed the impacts of rice cropping practices on yield-scaled GHG emissions. ► Significant differences showed in the yield-scaled GWP among rice cropping systems. ► N fertilization could reduce the yield-scaled GWP as compared to non-fertilization. ► Biogas residue, intermittent irrigation and no-tillage had lower yield-scaled GWP. ► Adjusting practices is a potential way to balance yield increase and GHG reduction. Recently increasing studies suggest that a comprehensive assessment of cropping practices impacts on greenhouse gas (GHG) emissions at yield-scale will benefit cropping technique innovation and policy selection for higher-yield with less-emissions. In this paper, we conducted a meta-analysis to quantify the impacts of rice cropping practices on the global warming potential (GWP) of GHG emissions at yield-scale rather than area-scale in China. The results showed that the yield-scaled GWP of Chinese major rice cropping systems during rice growing season was in the order: double rice cropping system (1188.9kg CO2equiv.Mg−1)>rice-upland crop rotation system (777.0kg CO2equiv.Mg−1)>single rice cropping system (346.7kg CO2equiv.Mg−1). Nitrogen fertilization (50–300kgNha−1) significantly increased rice yield with slight increments in the GWP of CH4 and N2O emissions, resulting in significant reductions in the yield-scaled GWP. The greatest reduction occurred at the application rate of 150–200kgNha−1 by 37% as compared to the non-fertilization control. For organic amendments, biogas residue application had no significant effect on the yield-scaled GWP, while manure application and straw recycling significantly increased the yield-scaled GWP by 54% and 154%, respectively. Intermittent irrigation significantly reduced yield-scaled GWP by 59% largely because of a significant reduction in CH4 emission and a significant increment in rice yield. No-tillage showed lower CH4 emission with similar rice yield in comparison with the conventional tillage, resulting in a reduction in yield-scaled GWP by 20%. These results indicate that there is a great potential to meet the new objective of higher-yield with less-GHG emissions through innovating rice cropping technique. More efforts should be paid on the field observations of GHG emissions during non-rice growing season, so as to perform a life-cycling assessment of GHG emissions from rice fields at yield scale under different cropping systems.