Enhanced‐efficiency fertilizers are not a panacea for resolving the nitrogen problem

• DOI: 10.1111/gcb.13918
• Publication Date: 2017-10-03T16:02:41Z
• Authors: Tingyu Li; Weifeng Zhang; Jiao Yin; David Chadwick; David Norse; Yuelai Lu; Xuejun Liu; Xinping Chen; Fusuo Zhang; David Powlson; Zhengxia Dou
• Keywords: Crops, Agricultural; 2. Zero hunger; Nitrogen; Climate Change; Agriculture; 04 agricultural and veterinary sciences; 15. Life on land; 6. Clean water; 12. Responsible consumption; 13. Climate action; 0401 agriculture, forestry, and fisheries; Fertilizers

Improving nitrogen (N) management for greater agricultural output while minimizing unintended environmental consequences is critical in the endeavor of feeding growing population sustainably amid climate change. Enhanced-efficiency fertilizers (EEFs) have been developed to better synchronize fertilizer N release with crop uptake, offering potential enhanced use efficiency (NUE) and reduced losses. Can EEFs play a significant role helping address challenge? Here we present comprehensive analysis worldwide studies published 1980-2016 evaluating four major types (polymer-coated PCF, nitrification inhibitors NI, urease UI, double DI, i.e. combined) regarding their effectiveness increasing yield NUE reducing Overall productivity efficacy depended on combination EEF type cropping systems, further affected by biophysical conditions. Best scenarios include: (i) DI used grassland (n = 133), averaging 11% increase, 33% improvement, 47% decrease aggregated loss (sum NO3- , NH3 N2 O, totaling 84 kg N/ha); (ii) UI rice-paddy systems 100), 9% 29% 41% N-loss reduction (16 N/ha). efficacies wheat maize were more complicated generally less effective. In-depth indicated that benefits might be best achieved when need created, example, downward adjusting application from conventional rate. We conclude can sustainable production but prudent requires firstly eliminating any mismanagement plus implementation knowledge-based practices.