1. Nitrous oxide emissions from China's croplands based on regional and crop-specific emission factors deviate from IPCC 2006 estimates
- Author
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Stuart Lindsey, Garba Aliyu, Mohammad Zaman, Jiafa Luo, Tiehu He, Junji Yuan, Zengming Chen, Hong J. Di, Deyan Liu, Weixin Ding, and Yongxin Lin
- Subjects
Crops, Agricultural ,China ,Environmental Engineering ,010504 meteorology & atmospheric sciences ,Nitrous Oxide ,Climate change ,Subtropics ,010501 environmental sciences ,engineering.material ,01 natural sciences ,Air Pollution ,Soil pH ,Environmental Chemistry ,Precipitation ,Cropping system ,Waste Management and Disposal ,0105 earth and related environmental sciences ,Air Pollutants ,Agriculture ,Soil classification ,Pollution ,Agronomy ,engineering ,Environmental science ,Paddy field ,Fertilizer ,Environmental Monitoring - Abstract
Calculated N2O emission factors (EFs) of applied nitrogen (N) fertilizer are currently based upon a single, universal value advocated by the IPCC (Inter-governmental Panel on Climate Change) even though EFs are thought to vary with climate and soil types. Here, we compiled and analyzed 151 N2O EF values from agricultural fields across China. The EF of synthetic N applied to these croplands was 0.60%, on average, but differed significantly among six climatic zones across the country, with the highest EF found in the north subtropical zone for upland fields (0.93%) and the lowest in the middle subtropical zone for paddy fields (0.20%). Precipitation and soil pH, which showed non-linear relationships with EF, are among the factors governing it, explaining 7.0% and 8.0% of the regional variation in EFs, respectively. Annual precipitation was the key factor regulating N2O emissions from synthetic N fertilizers. Among crop types, legume crops had the highest EFs, which were significantly (P
- Published
- 2019