Effect of Biochar Amendment on N₂O Emission from Latosol Soil

Purpose This study was aimed to investigate the effects of biochar on the nitrous oxide (N₂O) emission after two times of N application in latosol soil and provide basis for biochar and nitrogen fertilizer application.

Methods An incubation experiment with two times of the same amount of N fertilizer application after each 0, 1% and 2% (m/m) levels of biochar application was conducted to measure N₂O emission and related soil properties.

Results The soil pH, cation exchange capacity (CEC), soil organic carbon, available P, available K and total N increased with the rate of biochar application. Biochar application promoted nitrification which significantly decreased NH₄⁺-N (P<0.05) and increased NO₃⁻-N concentrations. Biochar application decreased N₂O emission after the first time of N fertilizer application (P<0.05), the higher the rate of biochar application was, the greater the reduction of N₂O emission was. However, biochar application promoted N₂O emission after the second time of N fertilizer application. Biochar application decreased total N₂O emission in the combination two times of N₂O emission.

Conclusion Biochar application significantly improved soil productivity and soil fertility, and alleviated soil acidification. Combined with water management, biochar application can mitigate N₂O emission.