Reducing nitrogen (N) leaching in acidic soil by amending urea fertilizer with rice husk biochar

Excessive applied of N fertilizers affects plants and environment, mainly through denitrification, runoff, leaching, volatilization, resulting in waste of resources and pollution. Biochar is a by-product of the pyrolysis of biomass wastes that have a high carbon content and porous structure, and have been widely used as soil modification in agro-ecosystems. The aim of this study were to (1) Sample and characterize the selected physio-chemical properties of soil samples to be used for laboratory leaching studies (2) Characterize the selected chemical properties of rice husk biochar (3) To determine the effect of amending urea with rice husk biochar on the retention of N in the soil and the chemical properties of the selected soil. The leaching experiment was performed for 30 days and water and soil samples were collected for analysis at the end of the experiment. The urea amended with different rates rice husk biochar did not reduce the N leaching and improve the N retention in the soil compared to treatment without applications of rice husk biochar. However, the rice husk biohcar managed to improve the soil pH to near neutral.