Nitrogen fertilizer: how much more efficient can we get?

Eventually, we will hit the biological limits of N use efficiency. But, for now, there is still room for improvement

by KEITH REID

Nitrogen (N) fertilizer has improved grain yields with huge economic benefits for the agricultural sector. However, it is a resource that needs careful management. Too little and crop yields suffer. Too much and it increases the risk of losses of ammonia and nitrous oxide to the air and nitrate to groundwater, not to mention increasing overall costs. 

Better Farming - February 2012