Enhanced greenhouse-gases emissions in an irrigated rice paddy fertilized with biofiltration leachate

摘要

To investigate how biofiltration leachate (BL) affects carbon dioxide (C02), methane, nitrous oxide (N20) emissions in rice paddies, we periodically collected air samples and soil-entrapped gas samples. Compared with the control plot where mineral fertilizers were applied, the BL plot showed significantly higher emissions of C02 and methane for both gas emissions through rice plants and the soil surface. We also found that the amounts of soil-entrapped C02 and methane were higher in the BL-treated plot. On the other hand, N20 emission was not significantly different between the treatments. The results suggest that biofiltration leachate, which had been subjected to various nitrogen processes in the biofile and thus is usually of low N content, mainly influences belowground carbon flux under anaerobic conditions, rather than nitrogen turnovers in the soil.