Effect of the Nitrogen Application to Spring Maize Nitrogen Absorption and Soil Nitrogen Balance in Northeast of China

The field experiments were conducted to investigate the effects of different nitrogen(N) application on spring maize growth,grain yield and the change of soil N content in Yushu,Jilin province.The results showed that the appropriate Nitrogen application can significantly increase grain yield,N 200 kg/ha at the ratio of 1 ∶ 0(basal N and topdressing N) treatment oversupply nitrogen at early growing season,cause to turn on the nitrogen was reduced.Excessively retained in the plant,the yield and nitrogen use efficiency is poorer than other treatments,N 200 kg/ha at the ratio of 1 ∶ 2 ∶ 2 treatments obtain higher nitrogen agriculture utilization,nitrogen utilization efficiency and nitrogen partial productivity.The reason of maize growth period in the field of the apparent nitrogen loss is one-time applying fertilizer excessively,while high topdressing N rates after elongation stage also increase soil N residual after the harvest. So in order to achieve high maize yield and improve nitrogen use efficiency,nitrogen fertilizer control should be combined with crop nutrient demand at different stages,soil nutrient supply,in order to reduce the harm by nitrogen fertilizer losses to the environment.