Furthering 4R Nutrient Management for Sustained Productivity

Fertilizer use has been a key factor in boosting crop yields worldwide, feeding a growing population, and relieving pressure for land use change. At the same time, the global use of nitrogen fertilizer is associated with greenhouse gas emissions of around 800 million tons of carbon dioxide equivalents each year. Crop producers and their advisers are under pressure to find ways to reduce those emissions, while continuing to increase crop yields and soil health. The principles of 4R nutrient Stewardship have much to offer toward this goal. The scope for reducing emissions from fertilizer by applying 4R practices is large but may require dramatic and costly changes. 

In Canada a 30% reduction by 2030 was found possible only with unrealistically high rates of adoption of advanced 4R practices. Globally, a 70% reduction by 2050 could be achieved, again only with massive improvements in NUE and 4R practice adoption. In both cases, only one quarter to one half of those reductions could be achieved in a manner cost-effective for farmers.  Farmers on their own do not have the resources to provide all the emission reductions possible. Farmers, industry, and government will need to work together to develop the monitoring, reporting, and verification needed for the programs to recognize and reward those adopting practices that reduce emissions.