不同类型氮肥与施氮量下夏玉米水、氮利用及土壤氮素表观盈亏

以两个夏播玉米品种为材料，研究了不同类型氮肥与不同施氮量下华北平原夏玉米的水分与氮素利用及土壤氮素表观盈亏．结果表明：（1）随施氮量增大．产量、耗水量及水分生产效率（WPE）增大，氮肥利用率（NUE）降低；（2）夏玉米WPE与NUE具有较明显的基因型差异。WPE郑单958较大。NUE农大108较大；（3）wPE与NUE均受到氮肥类型的影响．WPE郑单958复合肥〉普通尿素〉包膜尿素．农大108处理间差异较小，以复合肥略大，普通尿素和包膜尿素相当。与普通尿素相比，包膜尿素与复合肥利用率较高，郑单958施N90kg／hm^2与农大108施N180kg／hm^2时，两者对NUE的提高尤为明显；（4）本试验条件下，经过夏玉米生长季，两品种各处理均出现土壤氮素表观亏缺，亏缺量随施氮量增大而降低，各条件下郑单958亏缺量较农大108大；氮肥类型间土壤氮素表观亏缺量表现为复合肥〉包膜尿素〉普通尿素。

Water and Nitrogen Utilization and Apparent Budget of Soil Nitrogen under Different Types of Nitrogen Fertilizer and Different Application Rates in Summer Maize

Two summer maize cultivars,Zhengdan958 and Nongda108,were used,and the effect of different types of nitrogen fertilizer(NF) and different application rates on water and nitrogen utilization and apparent budget of soil nitrogen were studied.The main results are as follows:(1)With the increment of N application rate,yield,water use amount and water produce efficiency(WPE) increased but nitrogen use efficiency(NUE) decreased.(2)There existed obvious genotype difference in WPE and NUE in summer maize.WPE of Zhengdan958 was bigger than that of Nongda108,and NUE of Nongda108 was bigger.(3)WPE and NUE were affected by type of NF.As for WPE of Zhengdan958,compound fertilizer>common urea>coated urea,but the difference among treatments of Nongda108 was smaller,that of compound fertilizer was bigger and that of the other two type of NF was equal nearly.Compared with common urea,NUE of coated urea and compound fertilizer was bigger,especially when 90 kg N/hm~2 for Zhengdan958 and 180 kg N/hm~2 for Nongda108.(4)After summer maize season,all treatments of two cultivars showed soil N deficit(SND) and the amount of SND decreased with the increment of N application rate.In common,amount of SND of Zhengdan958 was bigger than that of Nongda108.The amount of soil N apparent deficit of three type NF showed compound fertilizer>coated urea>common urea.