The effects of nitrogen fertilizer application on methane and nitrous oxide emission/uptake in Chinese croplands

• Published in: Journal of Integrative Agriculture Vol. 15; no. 2; pp. 440 - 450
• Main Authors: SUN, Bin-feng, ZHAO, Hong, LÜ, Yi-zhong, LU, Fei, WANG, Xiao-ke
• Format: Journal Article
• Language: English
• Published: State Key Laboratory of Urban and Regional Ecology,Research Center for Eco-Environmental Sciences,Chinese Academy of Sciences,Beijing 100085,P.R.China 01.02.2016; University of Chinese Academy of Sciences,Beijing 100049,P.R.China%College of Resources and Environment,China Agricultural University,Beijing 100193,P.R.China%State Key Laboratory of Urban and Regional Ecology,Research Center for Eco-Environmental Sciences,Chinese Academy of Sciences,Beijing 100085,P.R.China; Elsevier
• Subjects: China; corn; crop yield; cropland; cropping systems; emission factor; emissions factor; fertilizer rates; global warming; global warming potential; greenhouse gas emissions; highlands; meta-analysis; methane; nitrogen; nitrogen fertilizer; nitrogen fertilizers; nitrous oxide; Oryza sativa; paddies; rice; soil; Triticum aestivum; wheat; Zea mays; 中国; 农田; 发射; 吸收; 排放因子; 施氮肥; 氧化亚氮; 甲烷; China; global warming potential; methane; nitrogen fertilizer; nitrous oxide; emission factor
• ISSN: 2095-3119; 2352-3425
• DOI: 10.1016/S2095-3119(15)61063-2

The application of nitrogen（N） fertilizer to increase crop yields has a significant influence on soil methane（CH_4） and nitrous oxide（N_2O） emission/uptake.A meta-analysis was carried out on the effect of N application on（i） CH_4 emissions in rice paddies,（ii） CH_4 uptake in upland fields and（iii） N_2O emissions.The responses of CH_4 emissions to N application in rice paddies were highly variable and overall no effects were found.CH_4 emissions were stimulated at low N application rates（〈100 kg N ha~（-1）） but inhibited at high N rates（〉200 kg N ha~（-1）） as compared to no N fertilizer（control）.The response of CH_4 uptake to N application in upland fields was 15%lower than control,with a mean CH_4 uptake factor of-0.001 kg CH_4-C kg~（-1） N.The mean N_2O emission factors were 1.00 and 0.94%for maize（Zea mays） and wheat（Triticum aestivum）,respectively,but significantly lower for the rice（Oryza sativa）（0.51%）.Compared with controls,N addition overall increased global warming potential of CH_4 and N_2O emissions by 78%.Our result revealed that response of CH_4 emission to N input might depend on the CH_4concentration in rice paddy.The critical factors that affected CH_4 uptake and N_2O emission were N fertilizer application rate and the controls of CH_4 uptake and N_2O emission.The influences of application times,cropping systems and measurement frequency should all be considered when assessing CH_4 and N_2O emissions/uptake induced by N fertilizer.