Effects of longevity of controlled-release fertilizer on N₂O emission reduction in bare soil and banana-planted soil

Objective  To study effects of longevity of controlled-release fertilizer (CRF) on mitigation of N₂O emission from bare soil and banana-planted soil, and to provide references for further research on mitigation of N₂O emission from the field.

Method  Using static chamber-GC technique, pot experiment was conducted to study N₂O fluxes and cumulative emission from bare soil and banana-planted soil fertilized with CRF of 1, 3 and 5 months longevity (marked as CRF 1Mon, CRF 3Mon and CRF 5Mon respectively).

Result  CRF longevity significantly affected the number of emission peaks, maximum emission peak flux, cumulative emissions and global warming potential of N₂O from bare soil and banana-planted soil. There were 5, 3 and 3 N₂O emission peaks of CRF 1Mon, CRF 3Mon and CRF 5Mon from bare soil in the middle and later stages. Maximum emission peak flux decreased in order of CRF 1Mon > CRF 3Mon > CRF 5Mon. The cumulative emissions of CRF 3Mon and CRF 5Mon were significantly lower than that of CRF 1Mon. There were 1 and 3 N₂O emission peaks of CRF 1Mon and CRF 3Mon from banana-planted soil only in the early stage. N₂O cumulative emissions decreased in order of CRF 1Mon > CRF 3Mon > CRF 5Mon. Prolonged CRF application was more effective on reducing N₂O emission from banana-planted soil than that from bare soil. The cumulative emission decreased by 24.06% to 52.81% in bare soil, and decreased by 54.22% to 75.34% in banana-planted soil.

Conclusion  Prolonged CRF application and crop planting can help effectively reduce soil N₂O emission and the greenhouse effect.