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

Abstract

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.

Keywords

• bottom ash
• nitrous oxide
• yield-scaled nitrous oxide emission