Characterization of Biochar from Different Feedstocks under Low and High Temperature and Their Effects on Greenhouse Gas Emission and Ammonia Volatilazation from Soil Incubation

Abstract

Biochar is a potential soil amendment that likely to reduce GHG emissions from land application to soil, but their properties depend on biomass types and pyrolysis temperature. In this study, biochars were produced from different biomasses (wet distiller grains (WDG), dry distiller grains (DDG), and corn stover (CS)) at two temperatures (low & high). Biochars were analyzed for pH, electrical conductivity, proximate and ultimate analysis, elemental analysis, and morphological structure. Also, biochar's efficacy on GHGs and ammonia (NH3) emission were measured from soil and manure incubated at 25℃ for 76 days. DDG and CS derived biochar properties outperformed other biochars. Manure treated with high-temperature DDG biochar emitted the lowest amount of N2O (0.09 mg N2O-N kg−1), and CH4 (0.04 mg CH4-C kg−1). Biochar application also reduced CO2 emission from 11 to 59%, but resulted in higher cumulative NH3 volatilization. Overall, biochars reduced GHG emissions when applied with N treatments.