Effects of Biomass Application on Soil Carbon Storage and Mitigation of GHGs Emission in Upland

Abstract

This experiment was carried out to find out the mitigation of greenhouse gases (GHGs) emission and changes of soil carbon contents in the cropland. In order to minimize the soil disturbance, this study was conducted without crop cultivation at the pots treated with different biomass. Different biomass was buried in the soil for 12 months. Decomposition rates of expander rice hull, pig manure compost and carbonized rice hull were 18%, 11~11.5% and 0.5~1.2%, respectively. It was appeared that carbonized rice hull was slightly decomposed. No difference was shown between chemical fertilizer treatment plot and non-application plot. It was appeared that soil carbon content in the non chemical fertilizer application plot was high when compared to its chemical fertilizer. Its content at soil depth of 20 cm more decreased than the upper layer of soil. Accumulative emission of CO₂ with different treatments of biomass was highest of 829.0~876.6 g CO₂ m -2 in the application plot of PMC (Pig Manure Compost) regardless of chemical fertilizer treatment during 16 months of experiment. However, the emission for expander rice hull treatment plot was lowest of 672.3~808.1 g CO₂ m -2 . For application plot of the carbonized rice hull, it was shown that non chemical fertilizer plot, 304.1 mg N₂O m-2, was higher than the chemical fertilizer treatment, 271.6 mg N₂O m -2 . Greenhouse gas emissions in the PMC treatment were highest of 0.94 ton CO₂ eq ha -1 yr -1 . However, it was estimated to be the lowest in the expander rice hull treatment.