Rethinking nitrogen fertilizer distribution could bolster sustainable agriculture globally

Researchers from the Karlsruhe Institute of Technology (KIT) have proposed a new approach to sustainable agriculture that addresses the dual challenges of food production and environmental conservation. According to a study published in Communications Earth & Environment, redistributing nitrogen fertilizer more uniformly across global croplands could significantly reduce its overall consumption without compromising crop yields.

Currently, about 60% of global nitrogen fertilizer consumption is used for staple crops like corn, wheat, and rice. While these fertilizers are essential for robust harvests, excessive use leads to soil and water pollution, biodiversity loss, climate change, and ozone layer degradation. This issue is particularly acute in major agricultural regions such as North America, Europe, and East Asia, where nitrogen fertilizer use is especially high.

Using the biogeochemical model LandscapeDNDC, KIT researchers simulated various scenarios of fertilizer use across different geographic locations. They then calculated the total production of corn, wheat, and rice from 2015 to 2030. Dr. Andrew Smerald, from KIT’s Institute of Meteorology and Climate Research, said, “Our work was focused on the question of how we can produce sufficient food without transgressing environmental boundaries.”

The study found that a more uniform distribution of nitrogen fertilizer could reduce global consumption by 32%. This would involve reallocating fertilizer from traditional farming regions in China, North America, and Europe to underutilized areas such as Sub-Saharan Africa. The shift would not only maintain current levels of grain production but also reduce nitrate leaching by up to 71% for wheat and 63% for corn.

According to Dr. Smerald, this redistribution strategy would offer multiple benefits. “A more equitable distribution would lessen our dependence on existing granaries and reduce nitrogen pollution in heavily fertilized regions,” he said. Furthermore, the approach could enable crops to be grown closer to their consumption points, and could assist regions like Africa in achieving agricultural self-sufficiency.