Nitrogen (N) is essential for crop growth and nitrogen fertilizers have been one of the primary drivers of increased crop yields (a key factor promoting food security) achieved over the past century. However, excess nitrogen that is not absorbed by plants can pollute both freshwater and marine water sources or be changed into ammonia by soil microbes, leading to greenhouse gas emissions, air pollution, as well as soil and water acidification. Increasing Nitrogen Use Efficiency (NUE) – the ratio between the amount of fertilizer N harvested in agricultural products (outputs) and the amount of fertilizer N applied (inputs) – can reduce excess nutrients lost to the environment, serving as an important indicator for monitoring nitrogen management and more sustainable agricultural systems. Ongoing NUE data are only available for a large subset of OECD members, for which the median NUE increased by about 20% between 1990 and 2010 and has plateaued since then.   

Nitrogen (N) is essential for crop growth and nitrogen fertilizers have been one of the primary drivers of increased crop yields (a key factor promoting food security) achieved over the past century. However, excess nitrogen that is not absorbed by plants can pollute both freshwater and marine water sources or be changed into ammonia by soil microbes, leading to greenhouse gas emissions, air pollution, as well as soil and water acidification. Increasing Nitrogen Use Efficiency (NUE) – the ratio between the amount of fertilizer N harvested in agricultural products (outputs) and the amount of fertilizer N applied (inputs) – can reduce excess nutrients lost to the environment, serving as an important indicator for monitoring nitrogen management and more sustainable agricultural systems. Ongoing NUE data are only available for a large subset of OECD members, for which the median NUE increased by about 20% between 1990 and 2010 and has plateaued since then.