Effect of biochar on the properties of loamy sand Spodosol soil samples with different fertility levels: A laboratory experiment

Abstract

The effect of biochar on the properties of a loamy sand Spodosol with different fertility level in the ploughed horizon has been studied in a 60-day laboratory experiment. It has been found that the application of biochar resulted in a significant increase of the soil water content in the range of soil-water potential from −5 to −50 kPa, a significant decrease of the total shrinkage of the soil with high level of fertility after three wetting-drying cycles, and the accumulation of a significantly higher content of nitrates in the soil. At a water content of 21%, less favorable conditions for the denitrification development were formed in the soil with high level of fertility than in the medium-fertile soil, which resulted in lower cumulative N2O emission from the former. The addition of biochar resulted in no significant changes in the cumulative emission of CO2 from the studied soil but significantly reduced the emission of N2O from the soil at the simultaneous addition of biochar and clover residues.