华北小麦施用脲铵氮肥实现轻简施肥的可行性及技术措施

Availability and technology of using urea-ammonium fertilizer to realize nitrogen reduction and simplified fertilization in wheat production of North China Plain

【目的】生产脲铵氮肥的目的是资源化利用联合制碱工业副产品。在华北平原多地开展了田间试验,探究适合冬小麦节肥增效的可行性和技术措施。【方法】于2021—2023年,分别在北京顺义、河北滦南、河北曲周、山东济南和河南禹州5个试验点进行了两年大田试验。设置尿素(U)、尿素减施30%(70%U)、脲铵氮肥减施30%(70%AU)、脲铵氮肥减施30%+脲酶抑制剂(N-丁基硫代磷酰三胺,NBPT)(70%AU+NBPT)、脲铵氮肥减施30%+硝化抑制剂(3,4-二甲基吡唑磷酸盐,DMPP)(70%AU+DMPP)、尿素减施30%+优化追肥时间(70%U+Opt)6个处理,测定了小麦产量及其构成因素、氮肥偏生产力、氮素吸收效率和土壤无机氮含量。【结果】与U处理相比,2022年减施氮肥处理(70%U、70%AU)在5个试验点中出现减产的试验点有1个,2023年有3个;70%AU+NBPT和70%AU+DMPP处理2022年出现减产的点有2个,2023年有2个;70%U+Opt两年均未出现减产。与U处理相比,在5个试验点两年多数处理显著提高了氮肥偏生产力和氮素吸收效率,2022、2023年氮肥偏生产力分别提高了19%~77%、23%~67%,氮素吸收效率分别提高了25%~77%、21%~71%。与U处理相比,2022年70%AU+NBPT和70%AU+DMPP处理土壤NH_(4)^(+)-N含量增加的试验点有5个,2023年有4个,2022、2023年分别增加了19%~69%、30%~90%;70%AU+NBPT和70%AU+DMPP处理2022年土壤NO_(3)^(-)-N含量降低的试验点有5个,2023年有4个,2022、2023年分别降低了19%~59%、34%~60%。【结论】与施用常规量尿素相比,减施氮投入量30%条件下,以脲铵氮肥为氮源或配合NBPT/DMPP,一次追施可以保证不减少产量,同时提高氮肥利用率。

【Objectives】Ammonium-urea fertilizer(AUF)is produced for the utilization of allied alkali industry by-products.We conducted field trials in the main winter wheat production regions of North China to explore the availability and technology of UAF in nitrogen reduction and simplified fertilization in these regions.【Methods】From 2021 to 2023,field trials were conducted over two years at five locations:Shunyi in Beijing,Luannan and Quzhou in Hebei,Jinan in Shandong,and Yuzhou in Henan.Field experiments contained six treatments,including urea at conventional rate(U),urea with 30%less N input(70%U),AUF with 30%less N input(70%AU),70%AU with N-(n-butyl)thiophosphoric triamide(70%AU+NBPT),70%AU with 3,4-dimethylpyrazole phosphate(70%AU+DMPP),and 70%U combined with optimal topdressing time(70%U+Opt).At harvesting period,wheat yield and yield components,partial factor productivity of nitrogen fertilizer(PFPN)and nitrogen uptake efficiency by wheat(NUE),and soil inorganic nitrogen concentrations were investigated.【Results】Compared to U treatment,nitrogen reduction treatments(70%U and 70%AU)decreased wheat yields in one experimental site in 2022,and three sites in 2023;70%AU+NBPT and 70%AU+DMPP treatments decreased yield in two sites in both 2022 and 2023,respectively;and 70%U+Opt treatment did not cause yield decrease over the two years.Compared to the U treatment,the majority of all the other treatments at the five sites increased PFPN and NUE over the two years,with PFPN increment from 19%to 77%in 2022 and 23%to 67%in 2023,and the NUE increment from 25%to 77%in 2022 and 21%to 71%in 2023.After wheat harvest,70%AU+NBPT and 70%AU+DMPP treatments were tested higher soil NH_(4)^(+)-N content and lower NO_(3)^(-)-N content than U treatment in five sites in 2022 and four sites in 2023,the gap in NH_(4)^(+)-N content was 19%−69%in 2022 and 30%−90%in 2023,and the gap in NO_(3)^(-)-N content was 19%−59%in 2022 and 34%−60%in 2023.【Conclusions】Under 30%of nitrogen reduction condition,the topdressing of ammonium-urea fertilizer or combination of NBPT or DMPP can maintain wheat yield and increase fertilizer nitrogen use efficiency.