US agricultural nitrous oxide emissions: context, status, and trends

• Published in: Frontiers in ecology and the environment Vol. 10; no. 10; pp. 537 - 546
• Main Authors: Cavigelli, Michel A, Grosso, Stephen J Del, Liebig, Mark A, Snyder, Clifford S, Fixen, Paul E, Venterea, Rodney T, Leytem, April B, McLain, Jean E, Watts, Dexter B
• Format: Journal Article
• Language: English
• Published: Ecological Society of America 01-12-2012
• Subjects: Agricultural management; Agricultural production; Agriculture; carbon dioxide; catalysts; Corn; Emissions reduction; Environmental agencies; environmental impact; Fertilizers; greenhouse gas emissions; greenhouse gases; Livestock; Manure; nitrogen; nitrous oxide; ozone depletion; Pollutant emissions; Reviews; stratosphere; Sustainable agriculture; United States; USA
• ISSN: 1540-9295; 1540-9309
• DOI: 10.1890/120054

The use of commercial nitrogen (N) fertilizers has led to enormous increases in US agricultural productivity. However, N losses from agricultural systems have resulted in numerous deleterious environmental impacts, including a continuing increase in atmospheric nitrous oxide (N
2
O), a greenhouse gas (GHG) and an important catalyst of stratospheric ozone depletion. Although associated with about 7% of total US GHG emissions, agricultural systems account for 75% of total US N
2
O emissions. Increased productivity in the crop and livestock sectors during the past 30 to 70 years has resulted in decreased N
2
O emissions per unit of production, but N
2
O emissions from US agriculture continue to increase at a rate of approximately 0.46 teragrams of carbon dioxide equivalents per year (2002-2009). This rate is lower than that during the late 20th century. Improvements in agricultural productivity alone may be insufficient to lead to reduced emissions; implementing strategies specifically targeted at reducing N
2
O emissions may therefore be necessary.