National greenhouse gas inventory should include the amount of nitrous oxide (N2O) emitted from the agricultural soils. Tier 1 methodology uses the emission factor from the amount of chemical nitrogen fertilizer, however, it does not reflect the specific effects of organic amendment to the Korean soils which is a common practice in the conventional farming system. In this sense, we need to develop national-specific emission factor from using different types and amounts of N2O emission. To do that, we set up a long-term field study in Chungcheongnam-do, Korea in May 2016 and conducted an intensive monitoring of N2O emission from the sweet potato field soils. Types of manure included the wastes from chicken, cow and pig and the amounts of application were Ⅹ1 and Ⅹ3 of recommended amounts. All the plots were triplicated and applied with NPK chemical fertilizer and controls of no addition was also employed. The emission rate was the highest in mid of May, 2016 when the soil contained high level of mineral nitrogen (N) due to fertilizer and manure application. The peaks coincided with the high soil water contents, indicating that applied mineral N was immediately emitted through microbial denitrification. In addition to the mineral N, organic N from different types of manure contributed the total N2O emission. The highest N2O was from the Ⅹ3 chicken manure treatment followed by Ⅹ3 cow manure and the third highest emission was from Ⅹ1 chicken manure. The rest of the treatments did not have significantly different emission rates. The higher N2O emission rate from chicken manure treatments was explained by higher N contents contained in the chicken manure. Our field study will be repeated two more times in 2017 and 2018 and after the QA/QC procedure, national specific N2O emission factor will be developed by different organic amendments
National greenhouse gas inventory should include the amount of nitrous oxide (N2O) emitted from the agricultural soils. Tier 1 methodology uses the emission factor from the amount of chemical nitrogen fertilizer, however, it does not reflect the specific effects of organic amendment to the Korean soils which is a common practice in the conventional farming system. In this sense, we need to develop national-specific emission factor from using different types and amounts of N2O emission. To do that, we set up a long-term field study in Chungcheongnam-do, Korea in May 2016 and conducted an intensive monitoring of N2O emission from the sweet potato field soils. Types of manure included the wastes from chicken, cow and pig and the amounts of application were Ⅹ1 and Ⅹ3 of recommended amounts. All the plots were triplicated and applied with NPK chemical fertilizer and controls of no addition was also employed. The emission rate was the highest in mid of May, 2016 when the soil contained high level of mineral nitrogen (N) due to fertilizer and manure application. The peaks coincided with the high soil water contents, indicating that applied mineral N was immediately emitted through microbial denitrification. In addition to the mineral N, organic N from different types of manure contributed the total N2O emission. The highest N2O was from the Ⅹ3 chicken manure treatment followed by Ⅹ3 cow manure and the third highest emission was from Ⅹ1 chicken manure. The rest of the treatments did not have significantly different emission rates. The higher N2O emission rate from chicken manure treatments was explained by higher N contents contained in the chicken manure. Our field study will be repeated two more times in 2017 and 2018 and after the QA/QC procedure, national specific N2O emission factor will be developed by different organic amendments