A Revised Estimate of N 2 O Emission Factor for Spring Chinese cabbage fields in Korea

Greenhouse-gas emission factors are widely used to estimate emissions arising from a defined unit of a specific activity. Such estimates are used both for international reporting to the United Nations Framework Convention on Climate Change (UNFCCC) and for a myriad of national and subnational reporting purposes. The Intergovernmental Panel on Climate Change (IPCC) provides a methodology for national and sub-national estimation of known greenhouse gas emissions including N2O for each sector from which the emissions arise. The objective of this study was to develop an emission factor to estimate the direct N2O emission from an agricultural field cultivated with Chinese cabbage during spring season in 2010-2012. An estimated emission factor of N2O calculated over three years from field experiment accounting for cumulative N2O emission, nitrogen fertilization rate, and background N2O emission was 0.0056±0.00254 (95% CI) Kg N2O-N/kg N. More extensive studies are needed to develop N2O emission factors for other upland crops in various regions of Korea because N2O emission is influenced by many factors including climate characteristics, soil properties agricultural practices and crop species.