Effect Of Long-term Fertilization On Aggregate, Fractions Of Organic Carbon And Micro-elements Of Black Soil

This paper studied32a fertilizing influence on aggregate, SOC, humus,MBC and POC in black soil. The results indicated aggregates were dominatedby the size class10~50μm in chemical fertilizer and CK, but chemicalfertilizer and organic fertilizer mixed and fallow area increased the size class50~250μm of aggregates. That indicated organic fertilizer and chemicalfertilizer mixed using can make forming of macro-aggregate largely, promotedforming of good soil structure. Fertilizing effected characteristicmicro-aggregates. Organic fertilizer and chemical fertilizer mixed can promotestoring and supplying moisture and nutrients of black soil. Fertilizer, evenly Nreduced MBC, POC content of black soil. In organic fertilizer and chemicalfertilizer mixed treatment, SOC, MBC, POC content was greater than othertreatments. Chemical fertilizer increased humic acids, HA, FA, HS contents,and increased humus activity. The different type of chemical fertilizer effectedHA/FA. Chemical fertilizer of N reduced humic acids content, but increasedhumus activity.This paper also studied long-term of32a different fertilization treatmentsinfluence on Mn, Fe, Cu, Zn content in the black soil. The results indicatedchemical fertilizer or organic and chemical fertilizer mixed increased availablemicro-elements content, compared with CK. But chemical fertilizer increasedavailable Mn, Fe content greatly, organic and chemical fertilizer mixedincreased available Cu, Zn content greatly. Available Mn, Fe mainly were affected by pH and clay (<1μm); available Cu, Zn were affected by SOC.Compared with fallow, fertilization and tillage promoted micro-elementscontent. Chemical fertilizer using increased total Mn significantly; organic andchemical fertilizer mixed treatment increased total Fe, Cu, Zn significantly.Class size5-10μm and30-100μm was most important portion. Totalmicro-elements were affected by soil particle composition. Particle Mn wasaffected mainly by clay (<1μm) and micro-aggregate (10-30μm). Particle Fewas affected mainly by SOC and clay (<1μm). Particle Cu, Zn was affectedmainly by SOC. Cu, Zn had powerful adjusting skills. Particle Cu, Zn was oneof available content of the origin. Particle micro-elements played a role of“temporary turnover station”.