Nitrous Oxide Emission and Crop Yield in Arable Soil Amended with Bottom Ash.

Bottom ash (BA), a byproduct of coal combustion from electric power plants with a porous surface texture and high pH, may influence the physical and chemical properties of upland arable soil associated with nitrous oxide (N₂O) emission from upland soil. This study evaluated the use of BA in mitigating N₂O emissions from upland arable soil and increasing the crop yield. In a field experiment, N₂O emitted from the soil was monitored weekly in a closed chamber over a 2-year period (2018–2019). BA was applied to upland soil at the rates of 0, 200, and 400 Mg·ha⁻¹. Cumulative N₂O emission significantly decreased with increasing BA application rate; it decreased by 55% with a BA application rate of 400 Mg·ha⁻¹ compared with the control. Yield-scaled N₂O emission decreased with increasing BA application rates of up to 200 Mg·ha⁻¹. Water-filled pore spaces (WFPS) were 70.2%, 52.9%, and 45.3% at the rates of 0, 200, and 400 Mg·ha⁻¹, respectively, during the growing season. For economic viability and environmental conservation, we suggest that BA application at a rate of 200 Mg·ha⁻¹ reduces N₂O emissions per unit of crop production. [ABSTRACT FROM AUTHOR]