不同施肥处理的土壤肥力指标及微生物碳、氮在玉米生育期内的动态变化

动态监测了沈阳农业大学棕壤长期定位试验站不同施肥处理土壤pH值、有机质、碱解氮、速效磷、速效钾及土壤微生物量碳、氮在玉米6个生育期内的变化.试验结果得出,长期施肥处理使土壤pH值降低;M4和M4N2P1处理使土壤有机质提高,而N4处理使土壤有机质降低;施肥处理土壤碱解氮含量都高于对照处理,在玉米生育期内土壤有机质和碱解氮变化都呈下降趋势;长期施用有机肥或有机无机肥配合施用可以大幅度提高土壤速效磷和速效钾的含量,M4处理土壤速效磷在玉米拔节期达到最大值.同时,除N4处理土壤微生物量碳、氮的平均值较对照降低外,其他施肥处理都较对照提高,且在抽雄期都表现出较高的水平.

Dynamical Changes of Soil Fertility and Microbial Biomass Carbon and Nitrogen in Different Fertilizations Within Corn Development Period

The dynamical changes of soil pH,organic matter,alkali-hydrolyzableN,quick-acting phosphorus,quick-acting kalium,and microbial biomass carbon and nitrogen in the soil of different fertilization treatments were monitored at the long-term located brown earth experiment site in Shengyang agricultural university within six growth periods of corn.The results indicated that long-term fertilizations made pH decline.The fertilization treatments of M4 and M4N2P1 make organic matter increase and N4 treatment make it decrease.The alkali-hydrolyzable-N in the soil of fertilizations is higher than CK.The trends of organic matter and alkali-hydrolyzable-N in corn growth periods remain decreasing.Organic matters and the combination of organic and inorganic matters can enhance quickacting phosphorus and quick-acting kalium in a large extent.The quick-acting phosphorus under M4 treatment reaches the climax in heading.Meanwhile,N4 treatment makes the average microbial biomass carbon and nitrogen decrease.While,M4 and M4N2P1 treatment makes them increase.The microbial biomass carbon and nitrogen in soil of fertilizations has very high content in the heading of corn.