中文摘要：

通过田间小区试验,比较研究了不同肥料类型、不同施氮量对夏玉米产量、氮肥利用率、土壤氮素表观盈亏量及植株氮素累积量的影响。结果表明,夏玉米产量随施氮量增大而增大,但施肥过量产量降低。同等施氮条件下,控释掺混氮肥各处理夏玉米产量和氮肥利用率均高于普通尿素处理。施氮显著增加了0-40cm土层土壤无机氮含量,同时显著提高了玉米生长中后期植株体内氮素含量。经夏玉米季后,除高量施氮的T4,T6处理出现土壤氮素表观盈余外,其余处理均出现土壤氮素表观亏缺,施氮后土壤表观盈余量增加,且随施氮量的增加而增加。

英文摘要：

This experiment was conducted to explore the effects of different N strategies on yield,nitrogen use efficiency （NUE）,apparent budget of soil N （ABSN） and content of N in plant. The results showed that yield increased with the application of N fertilizer,and yield reduced with the excessive N application rate. With the same nitrogen,the maize yield and nitrogen use efficiency of controlled-release nitrogen fertilizer （CRNF） with higher level compared with common urea. The mineral N content in soil layer （0-40 cm） are significantly increased with the increment of N application rate. The nitrogen contents in the plant and grain are increased by application of nitrogen fertilizer. After summer maize season,all treatments showed soil N deficit （SND） except T4,T6 and the amount of SND decreased with the increment of N application rate.