Abstract:

Field experiments were conducted in higher and lower fertility soil to evaluate effects on maize grain yield, soil residual NO3-N and N apparent losses of three nitrogen management strategies, conventional N splits by farmer, one shot dose fertilization by farmer and single basal application with polymer-coated urea (PCU) as partial N source. The results of two experiment sites showed that there was no significant difference on yields of different N management. Increase of 0-90cm soil residual NO3-N in Xinlicheng site of control, conventional fertilization, one shot does and single application with PCU treatments were -17.5，104.5，55.7，29.3kg N/hm2, and -44.3，-12.8，-57.2，-51.7 kg N/hm2 for higher fertility soil (Buhai site), respectively. The apparent N losses of whole stage were -83，-12，22 kg N/hm2 for lower fertility soil, and 172，119，157 kg N/hm2 for higher soil fertility soil. It indicated that less residual NO3-N increase with treatment of single application with PCU compared with other two strategies, and more apparent N losses resulted from rising of N rate.