长期定位施肥玉米生育期内微生物量碳、氮和微生物数量的动态变化

对吉林省公主岭市国家黑土肥力和肥料效益长期定位试验(2014年土样)进行测定和分析,探讨长期定位施肥条件下黑土中微生物量碳、氮和微生物数量在玉米生育期内的动态变化。结果表明,长期不同定位施肥处理黑土中微生物量碳、氮在玉米生育期内呈大致相同的变化规律,从苗期至拔节期下降,拔节期至开花期上升并达到峰值,开花期至收获期下降。微生物数量在苗期至拔节期变化不明显,开花期微生物数量急剧上升,达到峰值,开花期至灌浆期明显下降,并趋于稳定。黑土中微生物量碳、氮和微生物数量在玉米生育期内的动态变化表现出较好的一致性,长期不同定位施肥处理之间相比,有机无机配施、秸秆还田、玉米与大豆轮作等施肥措施可提高土壤中微生物量碳、氮含量和微生物数量。

Dynamic Changes of Microbial Biomass Carbon, Nitrogen and Microbial Quantity in Maize Growth Period under Long-term Fertilization

In order to investigate the dynamic changes of black soil microbial biomass carbon, nitrogen and microbial quantity during growth of maize, soil samples collected in 2014 were investigated based on the long-term experiment of national black soil and fertilizer efficiency in Gongzhuling City, Jilin Province, China. The results showed that: the microbial biomass carbon and nitrogen showed changes in roughly the same during maize growth period among different fertilization treatment. From seedling to jointing stage decreasing, jointing stage to the flowering period rising, peaked at the flowering period, flowering period to harvest declining; Microbial quantity does not change significantly from seedling to jointing stage, flowering period rising rapidly, peaked at flowering period, flowering period to filling stage significantly decreasing, and tending to be stable. The experimental results indicated that the fertilization measures, such as organic and inorganic fertilizer, straw returned, maize and soybean rotation, can increase the content of microbial biomass carbon, nitrogen and microbial quantity in black soil during maize growth period.