Nitrogen use (in)efficiency and cereal production in Brazil: current trends and forecasts

Here, we provide an analysis to understand the evolution of cereal production and consumption of nitrogen (N) fertilizers in Brazil and to correlate N use efficiency (NUE), greenhouse gas (GHG) emissions and economic and environmental losses. Our results showed that the increased consumption of N fertilizers is associated with a large decrease in NUE in recent years. CO2eq emissions from N fertilization for cereal production were approximately 12 times higher in 2011 compared to 1970. The projected N fertilizer forecasts are 2.09 and 2.37 million ton for 2015 and 2023, respectively. An increase of 0.02% per year in the projected NUE was predicted for the same time period. In a hypothetical scenario, a 2.39% increase in cereal NUE would lead to USD 21 million savings in N fertilizer costs. Thus, increases in NUE rates would lead not only to agronomic and environmental benefits but also to economic improvement.