Nitrogen Use in the United States from 1961–2000 and Potential Future Trends

Abstract Nitrogen inputs to the US from human activity doubled between 1961 and 1997, with most of the increase in the 1960s and 1970s. The largest increase was in use of inorganic N fertilizer, but emissions of NOx from fossil-fuel combustion also increased substantially. In 1961, N fixation in agricultural systems was the largest single source of reactive N in the US. By 1997, even though N fixation had increased, fertilizer use and NOx emissions had increased more rapidly and were both larger inputs. In both 1961 and 1997, two thirds of reactive N inputs were denitrified or stored in soils and biota, while one third was exported. The largest export was in riverine flux to coastal oceans, followed by export in food and feeds, and atmospheric advection to the oceans. The consumption of meat protein is a major driver behind N use in agriculture in the US Without change in diet or agricultural practices, fertilizer use will increase over next 30 years, and fluxes to coastal oceans may increase by another 30%. However, substantial reductions are possible.

[1]  A. Bouwman,et al.  Global use and trade of feedstuffs and consequences for the nitrogen cycle , 1998, Nutrient Cycling in Agroecosystems.

[2]  R. Howarth.  An assessment of human influences on fluxes of nitrogen from the terrestrial landscape to the estuaries and continental shelves of the North Atlantic Ocean , 1998, Nutrient Cycling in Agroecosystems.

[3]  E. W. Boyer,et al.  Where did all the nitrogen go? Fate of nitrogen inputs to large watersheds in the northeastern U.S.A. , 2002 .

[4]  Penny J Johnes,et al.  A comparison of models for estimating the riverine export of nitrogen from large watersheds , 2002 .

[5]  N. Rabalais.  Nitrogen in Aquatic Ecosystems , 2002, Ambio.

[6]  Jonathan A. Patz,et al.  Reactive Nitrogen and Human Health:Acute and Long-term Implications , 2002, Ambio.

[7]  C. Fu,et al.  The Asian Nitrogen Cycle Case Study , 2002, Ambio.

[8]  E. Cowling,et al.  Reactive Nitrogen and The World: 200 Years of Change , 2002, Ambio.

[9]  P. Matson,et al.  The Globalization of Nitrogen Deposition: Consequences for Terrestrial Ecosystems , 2002, Ambio.

[10]  V. Smil.  Nitrogen and Food Production: Proteins for Human Diets , 2002, Ambio.

[11]  L. Bouwman,et al.  The European Nitrogen Case , 2002, Ambio.

[12]  Elizabeth W. Boyer,et al.  Anthropogenic nitrogen sources and relationships to riverine nitrogen export in the northeastern U.S.A. , 2002 .

[13]  G. Gertner,et al.  Eutrophication: Nitrate flux in the Mississippi River , 2001, Nature.

[14]  S. Seitzinger,et al.  Future Trends in Worldwide River Nitrogen Transport and Related Nitrous Oxide Emissions: A Scenario Analysis , 2001, TheScientificWorldJournal.

[15]  W. Mitsch,et al.  Reducing Nitrogen Loading to the Gulf of Mexico from the Mississippi River Basin: Strategies to Counter a Persistent Ecological Problem , 2001 .

[16]  C. Hopkinson,et al.  Issues in ecology: Nutrient pollution of coastal rivers, bays, and seas , 2000 .

[17]  J. Sulzman,et al.  Contemporary and pre-industrial global reactive nitrogen budgets , 1999 .

[18]  V. Smil.  Nitrogen in crop production: An account of global flows , 1999 .

[19]  Richard P. Hooper,et al.  Flux and Sources of Nutrients in the Mississippi-Atchafalaya River Basin , 1999 .

[20]  A. Bouwman,et al.  A global high‐resolution emission inventory for ammonia , 1997 .

[21]  Gregory E. Schwarz,et al.  Regional interpretation of water‐quality monitoring data , 1997 .

[22]  G. Likens,et al.  Technical Report: Human Alteration of the Global Nitrogen Cycle: Sources and Consequences , 1997 .

[23]  Vaclav Smil,et al.  Global Population and the Nitrogen Cycle , 1997 .

[24]  David A. Kovacic,et al.  Nitrogen Balance in and Export from an Agricultural Watershed , 1997 .

[25]  J. Låg.  Some geomedical consequences of nitrogen circulation processes. , 1997 .

[26]  Donald E. Weller,et al.  Human contributions to terrestrial nitrogen flux , 1996 .

[27]  James N. Galloway,et al.  Atmospheric deposition of nutrients to the North Atlantic Basin. , 1996 .

[28]  Dennis P. Swaney,et al.  Regional nitrogen budgets and riverine N & P fluxes for the drainages to the North Atlantic Ocean: Natural and human influences , 1996 .

[29]  J. Schnoor,et al.  Nitrogen fixation: Anthropogenic enhancement‐environmental response , 1995 .

[30]  P. Crutzen,et al.  A three-dimensional model of the global ammonia cycle , 1994 .

[31]  A. Bouwman,et al.  Computing land use emissions of greenhouse gases , 1994 .

[32]  Board on Agriculture.  Soil and Water Quality: An Agenda for Agriculture , 1993 .

[33]  Sharon Nizich,et al.  NATIONAL AIR POLLUTANT EMISSION TRENDS, 1900-1992.. , 1993 .

[34]  R. Dickerson,et al.  The flux of reactive nitrogen compounds from Eastern North America to the Western Atlantic Ocean , 1987 .

[35]  J. Galloway,et al.  Watox-86 overview and western North Atlantic Ocean S and N atmospheric budgets , 1987 .

[36]  H. Levy,et al.  Fate of US and Canadian combustion nitrogen emissions , 1987, Nature.

[37]  G. Wolff,et al.  The flux of s and n eastward from north America , 1984 .

[38]  Jennifer A. Logan,et al.  Nitrogen oxides in the troposphere: Global and regional budgets , 1983 .

[39]  A. Nishida.  Numerical modeling of the energy spectrum of the cosmic ray Forbush Decrease , 1983 .