Abstract
We aimed at investigating the difference in N₂O emission factors of chemical and organic fertilizers and identifying the main factors influencing annual fluctuations in N₂O emission. We conducted two-year experiments in 2016 and 2017 in an agricultural field planted with sweet potato (Ipomoea batatas). Treatments included chemical NPK fertilizer (NPK) and chicken compost application at 10 ton ㏊SUP-1/SUP, 20 ton ㏊SUP-1/SUP, and 30 ton ㏊SUP-1/SUP rates (CK1, CK2 and CK3). Control was also employed with no addition. Results showed that N₂O emission rates were significantly related with soil water status and soil available N contents. Significant correlation between % water filled pore space (WFPS) and N₂O emission was observed only when the %WFPS was greater than 40% and during the initial stage of the experiment (＜60 d). Comparison of the emission factors in 2016 and 2017 showed us that the emission factor was greater in 2016 when the %WFPS was maintained higher by 16.5% compared to that in 2017. In 2016, the emission factor of organic fertilizer was higher than that of chemical fertilizer, while in 2017, the pattern was reversed. Annual variability in N₂O emission could also be originated from the available N contents remaining in soil after being taken up by plants. If we apply excessive N fertilizer, the soil would contain excess amount of N which was not uptaken by plants, leading to a huge increase in N₂O emission. This case would overestimate emission factor, which was the case for the organic fertilizer in 2016. Over-fertilization should be avoided when we set up an experiment to determine N₂O emission factor.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
