【摘要】 通过田间试验,采用静态箱法研究不同施氮水平下控释肥和尿素(N 0、100、200、270 kg hm-2)对麦季N2O排放的影响。结果表明,与对照相比,整个小麦生长季N2O排放量均随尿素和控释肥施用量的增加呈指数增加(32%～164%,p<0.05),但控释肥处理增加程度则较尿素处理缓和;施用控释肥可以有效抑制小麦生长季N2O排放(p<0.05),控释肥对N2O的减排量随着施氮量的增加而增加。小麦产量随尿素施用量的增加呈抛物线增加(24%～43%,p<0.05),随控释肥施用量的增加亦呈抛物线增加(30%～45%,p<0.05);与施用相同水平尿素相比,施用控释肥的小麦产量略有增加,但无显著差异(p>0.05)。单位产量N2O排放量随尿素施用量的增加而呈指数增加(31%～114%,p<0.05),随控释肥施用量的增加而呈抛物线增加(2%～50%,p<0.05);施用控释肥可以有效抑制小麦生长季单位产量N2O排放(p<0.05),控释肥对单位产量N2O的减排量随着施氮量的增加而增加。各处理N2O排放量与土壤水分存在显著正相关(p<0.05),与土壤NH4+-N、NO3--N浓度和土温不呈明显线性关系(p>0.05)。更多还原

【Abstract】 A field experiment was conducted to study effect of application rate(N 0,100,200 and 270 kg hm-2) of controlled-release fertilizer(CRF) and urea on N2O emission from the wheat cropping system.Seven treatments,i.e.CK,U100,U200,U270,C100,C200 and C270,were designed and implemented separately during the wheat growing period.Results indicate that application of either urea and CRF,increased total N2O emission during the wheat growing period exponentially from 32% to 164% with increasing N-fertilizer application rate(p<0.05).The increasing tendency was duller in Treatments CRF than in Treatments Urea.Compared with Treatments urea,Treatments CRF inhibited significantly N2O emission during the wheat growing period(p<0.05),and the effect was enhanced with increasing application rate.Compared with that in Treatment CK,grain yield increased in a parabolic pattern from 24% to 43% in Treatments Urea and from 30% to 45% in Treatments CRF with increasing application rate(p<0.05).Obviously the effect of Treatment CRF was slightly higher than that of Treatment Urea(p>0.05).Specific N2O emission increased exponentially from 31% to 114% in Treatment Urea with increasing application rate(p<0.05),and from 2% to 50% in Treatment CRF,showing while in parabolic pattern(p<0.05).CRF inhibited significantly specific N2O emission(p<0.05),and the effect increased with increasing application rate.Significant positive correlations were observed between N2O flux and soil water content(p<0.05) in all the treatments,while no significant linear correlation was found between N2O flux and soil NH+4-N and NO-3-N concentrations,or soil temperature(p>0.05).更多还原