Evaluation of Biochar On Reducing Nitrogen Leaching From a Typical Soil in Nova Scotia

Abstract

Biochar has been recently used as a soil amendment on reducing the nitrogen (N) leaching from agricultural soils to the surface and ground waters. A laboratory study using column leaching tests to determine the effectiveness of different types of biochars under different dosages on reducing leaching of nitrate and ammonium from an agricultural soil in Nova Scotia. A significant (p<0.05) decrease in the amount of nitrate leached from ‘fertilized’ soil was observed on biochar treatments comparing to the control treatment. Poultry manure derived biochars were more effective on reducing nitrate leaching than wood derived biochars. Poultry manure biochars produced at high temperature showed the lowest cumulative nitrate leaching than other types of biochars. Biochar applied at rate of 5 g kg-1 of soil showed non-significant difference on reducing nitrate leaching compared with application rate of 10 g kg-1 of soil except for MH biochar, which reduced more nitrate from leaching at higher application rate. Soil received wood-derived biochars showed non-significant lower ammonium leaching than soil received non-biochar. Poultry manure derived biochars prone to increase the ammonium leaching over times.