有机无机肥配施对酸性菜地土壤硝化作用的影响

Effects of combined application of manure and chemical fertilizer on the nitrification in acid vegetable soil

通过室内培养和田间试验,研究了有机无机肥配施对酸性菜地土硝化作用的影响。培养试验条件为60%土壤最大持水量和25℃。结果表明,土壤硝化作用模式为指数方程,延滞期10天。与纯化肥处理(NPK)相比,鲜猪粪配施无机肥(FPM+NPK)和猪粪堆肥配施无机肥(CPM+NPK)均能降低土壤硝化势和氨氧化潜势,猪粪堆肥配施无机肥还能增加土壤微生物量碳、氮。鲜猪粪配施无机肥和猪粪堆肥配施无机肥处理在硝化培养和田间试验期间N2O释放量均没有差异,但硝化培养期间鲜猪粪配施无机肥的N2O释放量显著低于纯化肥处理,田间试验期间猪粪堆肥配施无机肥的N2O释放量显著低于纯化肥处理。培养试验结束后的土壤pH值与土壤硝化势间,以及硝化培养期间N2O累积释放量与土壤硝化势间均存在显著正相关关系。本研究表明,有机无机肥配施显著影响土壤硝化作用以及硝化培养期间和田间N2O释放。

A laboratory soil incubation experiment with moisture content of 60%water holding capacity （ WHC） at 25℃was conducted to study the effect of combined application of manure and chemical fertilizer on the nitrification in acid vegetable soil .The results show that the time dependent NO 3--N accumulation was in exponential mode with a delay of 10 days for all treatments .Potential nitrification rate and ammonia oxidizing rate decreased significantly with treatment of adding fresh pig manure plus NPK fertilizer （ FPM＋NPK） and treatment of compost pig manure plus NPK （ CPM ＋NPK ） compared to NPK treatment .The soil microbial biomass carbon and soil microbial biomass nitrogen increased significantly with CPM ＋NPK treatments compared to NPK treatment in field condition . There was no significant difference with N 2 O emissions from nitrification incubation between FPM ＋NPK and CPM＋NPK treatments , however the N 2 O emissions from nitrification incubation with FPM ＋NPK treatment was significant lower than that with NPK treatment in incubation condition , and the N2 O emissions with CPM ＋NPK treatment was significant lower than that with NPK treatment in the field experiment .There were significant positive correlations between soil pH values and potential nitrification rate in the incubation end , as well as cumulative N 2 O emissions from nitrification incubation and potential nitrification rate .Combined application of manure and chemical fertilizer significantly changed soil nitrification and N 2 O emissions from nitrification incubation and field soil.