Contribution of silicate fertilizer application to reducing CH4 emission and increasing productivity in Korean rice paddies

Abstract

Iron slag-based silicate fertilizer, a byproduct of the iron production process, has been applied as a soil amendment in Korean and Japanese rice paddies for over 50 years. Silicate fertilizer application is known to improve rice productivity and decrease methane (CH4) emissions. In Korea, CH4 emissions from rice paddy have dropped by around 50 % from 1990 to 2020, which might be attributed to the declining cropping area. In estimating the national CH4 flux inventory from the rice paddies, the emission factor (i.e., EFbaseline x EForganic matter x EFwater regime) and activity data (i.e., area and cultivation period) are considered. However, the silicate fertilizer application effect on CH4 flux has not been considered.