【目的】研究不同肥效期的控释肥对裸地和栽培作物土壤N_2O减排效果的影响,为进一步研究大田条件下的减排效果提供参考。【方法】通过盆栽试验,采用静态箱法和气相色谱分析技术,对比研究了1、3、5个月3个肥效期的植物油包膜控释肥(CRF 1Mon、CRF 3Mon和CRF 5Mon)及其核心复合肥分别在裸地和栽培香蕉土壤中的N_2O日排放通量和累积排放量。【结果】控释肥肥效期显著影响N_2O排放峰数量、最大排放峰通量、累积排放量及增温潜势。裸地时,CRF 1Mon、CRF 3Mon和CRF 5Mon排放峰数量分别为5、3和3个,出峰时间均为监测的中后期,最大排放峰通量为CRF 1Mon〉CRF 3Mon〉CRF 5Mon,CRF 3Mon和CRF 5Mon的累积排放量显著低于CRF1Mon;栽培香蕉时,仅CRF 1Mon和CRF 3Mon在监测前期有明显的N_2O排放峰,分别为1和3个,累积排放量为CRF 1Mon〉CRF 3Mon〉CRF 5Mon。施用肥效期长的控释肥对栽培香蕉土壤的N_2O减排效果优于裸地,裸地时累积排放量降幅为24.06%~52.81%,栽培香蕉土壤的累积排放量降幅为54.22%~75.34%。【结论】施用肥效期长的控释肥以及栽培作物是减少土壤N_2O排放、降低温室效应的有效措施。
【Objective】To study effects of longevity of controlled-release fertilizer( CRF) on mitigation of N_2O emission from bare soil and banana-planted soil,and to provide references for further research on mitigation of N_2O emission from the field.【Method】Using static chamber-GC technique,pot experiment was conducted to study N_2O 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 N_2O from bare soil and bananaplanted soil. There were 5,3 and 3 N_2O 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 N_2O emission peaks of CRF 1Mon and CRF 3Mon frombanana-planted soil only in the early stage. N_2O cumulative emissions decreased in order of CRF 1Mon CRF 3Mon CRF 5Mon. Prolonged CRF application was more effective on reducing N_2O 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 N_2O emission and the greenhouse effect.