Optimizing nitrogen fertilizer use for more grain and less pollution. (1st August 2022)

• Record Type: Journal Article
• Authors: Ren, Keyu; Xu, Minggang; Li, Rong; Zheng, Lei; Liu, Shaogui; Reis, Stefan; Wang, Huiying; Lu, Changai; Zhang, Wenju; Gao, Hui; Duan, Yinghua; Gu, Baojing
• Is Part Of: Journal of cleaner production. Volume 360(2022)
• Publication Date: 2022-08-01
• Subjects: Crop yield -- Nitrogen use efficiency -- Nitrogen surplus -- Environmental sustainability -- Nitrogen management; Factory and trade waste -- Management -- Periodicals; Manufactures -- Environmental aspects -- Periodicals; Déchets industriels -- Gestion -- Périodiques; Usines -- Aspect de l'environnement -- Périodiques; 628.5
• DOI: 10.1016/j.jclepro.2022.132180
• Languages: English
• ISSNs: 0959-6526

Abstract

Abstract: Optimal nitrogen (N) management is critical for efficient crop production and agricultural pollution control. Approximate 210–220 kg ha −1 N fertilizer was applied in millions of small plots through broadcasting way in China, resulting in over and loss of N fertilizers. However, it is difficult to implement advanced management practices on smallholder farms due to a lack of knowledge. Here, using 35, 502 on-farm fertilization experiments, we demonstrated that smallholders in China could actually produce more grain with less N fertilizer use only through optimizing N application rate. The yields of wheat, maize and rice were shown to increase between 10% and 19% while N application rates were reduced by 15–19%. These changes resulted in an increase in N use efficiency (NUE) by 32–46% and a reduction in N surplus by 40% without actually changing farmers' operational practices. By reducing N application rates in line with official recommendations would not only save fertilizer cost while increasing crop yield, but also at the same time reduce environmental N pollution in China. Beyond of optimizing N application rate, improved management practices were required to produce more grain with less pollution, which would need about 11.8 billion US dollars for the implementation and reducing N loss reduction by 1.75 million tons to the environment. Graphical abstract: Image 1 Highlights: Optimizing N fertilizer rate was estimated based on 35, 502 field experiments nationally. Optimizing N rate increased NUE by 32–46% with 40% lower N surplus. Environmental N loss was predicted to be reduced by 5.06 million t by optimizing N rate. Best management strategies could result in 1.75 million tons N loss reduction.