有机肥替代化肥对土壤肥力和玉米产量的影响

Effects of substitution of chemical fertilizers by organic fertilizer on soil fertility and maize yield

为研究有机肥替代化肥对土壤培肥和玉米产量的影响,在北京市房山区布置田间小区试验,试验设置不施肥对照(CK)、常规化肥(CN)、常规化肥等氮量的有机肥(ON)、有机肥使用量是ON处理的一半(0.5 ON)、一半化肥氮一半有机肥氮(0.5 CN)5个处理。结果表明:有机肥替代100%化肥处理第2年玉米产量降低,降幅5.2%~6.7%,第3年减产幅度扩大;有机肥替代50%化肥可提高玉米产量11.8%。施用有机肥处理明显提高土壤有机质、速效氮磷钾、微生物生物量碳等指标。有机肥替代50%化肥氮处理下土壤碱解氮、速效钾含量增幅分别达到53.2%和38%,且和玉米产量具有显著性正相关关系。有机肥替代50%化肥氮处理可增加土壤微生物量碳和脲酶活性,改善土壤性质的同时增加土壤0.01~0.05 mm粒径团聚体的比例,是值得推广的施肥模式。

In order to study the effects of organic fertilizer substitution of chemical fertilizer on soil fertility and corn yield,a field plot experiment was conducted in Fangshan district,Beijing.Five treatments were set up:blank control(CK),conventional chemical N fertilization(CN),organic N fertilization with equal N with CN(ON),organic N fertilization with half N with ON(0.5 ON),half of chemical fertilizer nitrogen and half of organic fertilizer nitrogen(0.5 CN).The results showed that the replacement of 100%chemical fertilizer with organic fertilizer reduced the yield of corn by 5.2%~6.7%,and there was a tendency to further decrease;the replacement of 50%chemical fertilizer by organic fertilizer increased corn yield by 11.8%.The application of organic fertilizer significantly increased soil organic matter,available nitrogen,phosphorus,potassium and microbial biomass.For organic fertilizer substitution of 50%chemical fertilizer nitrogen treatment,the soil available nitrogen and available potassium increased by 53.2%and 38%,and this treatment had a significant positive correlation with corn yield.The replacement of 50%fertilizer nitrogen by organic fertilizer can increase soil microbial biomass carbon and urease activity,improve soil properties and increase soil particle size ratio of 0.01~0.05 mm,which is worthy of popularization.