Biochar prepared at different pyrolysis temperatures affects urea-nitrogen immobilization and N ₂ O emissions in paddy fields

Abstract

Irrespective of pyrolysis temperature, biochar had a positive effect on residual soil ¹⁵N content, while it negatively affected the ¹⁵N recovery of rice, N₂O emissions from soil, rice biomass, and grain yield in the first year. Generally, a high application rate of biochar prepared at high or low pyrolysis temperature reduced the N fertilizer-induced N₂O emission factor considerably. These biochar effects were dependent on N fertilizer level, biochar application rate, and their interactions.