氮肥调控对东北黑土春玉米氮利用及氨挥发的影响

Effects of Nitrogen Fertilizer Regulation on Nitrogen Utilization and Ammonia Volatilization from Maize Farmland in Black Soil Region of Northeast China

2018和2019年在吉林省梨树县开展大田定点试验,共设置6个处理,不施氮对照(N0)、常规施氮(NConv)、优化施氮(氮分次后移,NOPT)、控释氮肥(掺混30%控释尿素,NCtrl)、增施有机肥(在NOPT基础上增施有机肥,FM)和秸秆还田(在NCtrl基础上进行秸秆全量还田,SR),采用通气法田间原位监测不同管理措施下的氨挥发通量,并计算氮肥利用效率及氮平衡,明确氮肥调控对东北黑土春玉米氮利用及氨挥发的影响。结果表明,与NConv相比,各处理NOPT、NCtrl、FM、SR分别提高了14.1%、15.6%、24.2%和27.1%的氮肥利用效率。与N0、NConv、NCtrl、SR处理相比,NOPT、FM处理显著提高了氨挥发累积量,分别达氮肥施用量的3.2%和4.2%。NOPT处理减少了46.2%的氮表观损失和30.1%的氮盈余。在氮肥施用量、施用时期和肥料类型等方面进行调控,可在稳产的同时大幅提高氮肥利用效率。施用控释氮肥可显著减少氨挥发损失。采用“掺混控释氮肥+秸秆还田”的调控措施更有利于增产增效,并减少环境污染风险。

In order to understand the effects of nitrogen regulation on nitrogen utilization and ammonia volatil⁃ization from maize farmland in the black soil region of Northeast China.Field experiments were conducted in Lishu county of Jilin province in 2018 and 2019.Six treatments were set up:no nitrogen as control(N0),conventional nitro⁃gen application(Nconv),optimized nitrogen application(Nopt),controlled-release nitrogen fertilizer application(Nctrl),or⁃ganic fertilizer addition(FM)and straw returning(SR).The ammonia volatilization fluxes under different manage⁃ments were determined in situ by venting method,and nitrogen use efficiency and nitrogen balance were calculated.he results showed that compared with the Nconv treatment,the nitrogen use efficiency was significantly increased by 14.1%,15.6%,24.2%and 27.1%in the treatments Nopt,Nctrl,FM,and SR,respectively.Compared with N0,NConv,NCtrl,and SR,the NOPT and FM treatments significantly increased the total ammonia volatilization,accounting for 3.2%and 4.2%of the nitrogen fertilizer application rate,respectively.The estimated results of nitrogen balance showed that the Nopt reduced the apparent nitrogen losses by 46.2%and the nitrogen surplus by 30.1%.The nitrogen use efficiency can be greatly improved while the yield is stable by regulating the amount,period,and type of nitro⁃gen fertilizer.The application of controlled-release nitrogen fertilizer can significantly reduce the loss of ammonia volatilization.Therefore,the management of“controlled-release nitrogen fertilizer application+straw returning”is more conducive to increase maize yield and nitrogen efficiency and reduce the risk of environmental pollution.