, Volume 26, Issue 3, pp 803–814 | Cite as

Sources of nitrogen to estuaries in the United States

  • Mark S. Castro
  • Charles T. Driscoll
  • Thomas E. Jordan
  • William G. Reay
  • Walter R. Boynton


The purpose of this study was to quantify the nitrogen (N) inputs to 34 estuaries on the Atlantic and Gulf Coasts of the United States. Total nitrogen (TN) inputs ranged from 1 kg N ha−1 yr−1 for Upper Laguna Madre, Texas, to 49 kg N ha−1 yr−1 for Massachusetts Bay, Massachusetts. TN inputs to 11 of the 34 estuaries were dominated by urban N sources (point sources and septic systems) and nonpoint source N runoff (5% of total); point sources accounted for 36–86% of the TN inputs to these 11 urban-dominated estuaries. TN inputs to 20 of the 34 estuaries were dominated by agricultural N sources; N fertilization was the dominant source (46% of the total), followed by manure (32% of the total) and N fixation by crops (16% of the total). Atmospheric deposition (runoff from watershed plus direct deposition to the surface of the estuary) was the dominant N source for three estuaries (Barnegat Bay, New Jersey: 64%; St. Catherines-Sapelo, Georgia: 72%; and Barataria Bay, Louisiana: 53%). Six estuaries had atmospheric contributions ≥30% of the TN inputs (Casco Bay, Maine: 43%; Buzzards Bay, Massachusetts: 30%; Great Bay, New Jersey: 40%; Chesapeake Bay: 30%; Terrebonne-Timbalier Bay, Louisiana: 59%; and Upper Laguna Madre: 41%). Results from our study suggest that reductions in N loadings to estuaries should be accomplished by implementing watershed specific programs that target the dominant N sources.


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Literature Cited

  1. Alexander, R. B., R. A. Smith, andG. E. Schwarz. 2000b. Effect of stream channel size on the delivery of nitrogen to the Gulf of Mexico.Nature 403:758–761.CrossRefGoogle Scholar
  2. Alexander, R. B., R. A. Smith, G. E.Schwartz, S. D. Preston, J. W. Brakebill, R. Srinivasan, andP. A. Pacheco. 2000. Atmospheric nitrogen flux from the watersheds of major estuaries of the United States: An application of the SPARROW watershed model, p. 119–170.In R. M. Valigura, R. B. Alexander, M. S. Castro, H. Greening, T. Meyers, H. Paerl, and R. E. Turner (eds.), An Assessment of Nitrogen Loads to United States Estuaries with an Atmospheric Perspective. Coastal and Estuarine Studies, American Geophysical Union, Washington, D.C.Google Scholar
  3. Boynton, W. R., J. H. Garber, R. Summers, andW. M. Kemp. 1995. Inputs, transformations, and transport of nitrogen and phosphorus in Chesapeake Bay and selected tributaries.Estuaries 18:285–314.CrossRefGoogle Scholar
  4. Castro, M. S., C. T. Driscoll, T. E. Jordan, W. G. Reay, W. R. Boynton, S. P. Seitzinger, R. V. Styles, andJ. E. Cable. 2000. Contribution of atmospheric deposition to the total nitrogen loads to thirty-four estuaries on the Atlantic and Gulf coasts of the United States, p. 77–106.In R. M. Valigura, R. B. Alexander, M. S. Castro, H. Greening, T. Meyers, H. Paerl, and R. E. Turner (eds.), An Assessment of Nitrogen Loads to United States Estuaries with an Atmospheric Perspective. Coastal and Estuarine Studies. American Geophysical Union, Washington, D.C.Google Scholar
  5. D'Elia, C. F., L. W. Harding, Jr.,M. Leffler, andG. B. Mackiernan. 1992. The role and control of nutrients in Chesapeake Bay.Water Science Technology 26:2635–2644.Google Scholar
  6. Fisher, D. C. andM. Oppenheimer. 1991. Atmospheric nitrogen deposition and the Chesapeake Bay estuary.Ambio 20:102–108.Google Scholar
  7. Goolsby, D. A. 2000. Mississippi basin nitrogen flux believed to cause Gulf hypoxia.EOS Transactions 2000:29–321.Google Scholar
  8. Howarth, R. W., D. A. Anderson, T. M. Church, H. Greening, C. S. Hopkinson, W. C. Huber, N. Marcus, R. J. Naiman, K. Segerson, A. N. Sharpley, andW. J. Wiseman. 2000. Clean Coastal Waters: Understanding and Reducing the Effects of Nutrient Pollution. National Academy Press, Washington, D.C.Google Scholar
  9. Howarth, R. W., G. Billen, D. Swaney, A. Townsend, N. Jaworski, K. Lajtha, J. A. Downing, R. Elmgren, N. Caraco, T. Jordan, F. Berendse, J. Freney, V. Kudeyarov, P. Murdoch, andZ.-L. Zhu. 1996. Regional nitrogen budgets and riverine N and P fluxes for the drainages to the North Atlantic Ocean: Natural and human influences.Biogeochemistry 35:75–139.CrossRefGoogle Scholar
  10. Jaworski, N. A., R. W. Howarth, andL. J. Hetling. 1997. Atmospheric deposition of nitrogen oxides into the landscape contributes to coastal eutrophication in the northeast United Strates.Environmental Science and Technology 31:1995–2004.CrossRefGoogle Scholar
  11. Maag, M., M. Malinovsky, andS. M. Nielson. 1997. Kinetics and temperature dependence of potential denitrification in riparian soils.Journal of Environmental Science 26:215–223.Google Scholar
  12. Meybeck, M., D. V. Chapman, andR. Helmer. 1989. Global freshwater quality: A first assessment. World Health Organization/United Nations Environment Programme. Basil Blackwell, Inc., Cambridge, Massachusetts.Google Scholar
  13. Meyers, T., J. Sickles, R. Dennis, K. Russell, J. Galloway, andT. Church. 2000. Atmospheric nitrogen deposition to coastal estuaries and their watersheds, p. 53–76.In R. M. Valigura, R. B. Alexander, M. S. Castro, H. Greening, T. Meyers, H. Paerl, and R. E. Turner (eds.), An Assessment of Nitrogen Loads to U.S. Estuaries with an Atmospheric Perspective. Coastal and Estuarine Studies, American Geophysical Union, Washington, D.C.Google Scholar
  14. Nixon, S. 1986. Nutrient dynamics and productivity of marine coastal waters, p. 97–115.In B. Clayton and M. Behbehani (eds.), Coastal Eutrophication. The Alden Press, Oxford, U.K.Google Scholar
  15. Nixon, S. 1995. Coastal marine eutrophication: A definition, social causes and future concerns.Ophelia 41:199–220.Google Scholar
  16. Pacheco, P. A. 1999. Coastal assessment and data synthesis framework. National Coastal Assessment (NSA) Branch, Special Projects Office (SPO), National Ocean Service (NOS), National Oceanic and Atmospheric Administration (NOAA). Silver Spring, Maryland.Google Scholar
  17. Paeri, H. 1988. Nuisance phytoplankton blooms in coastal, estuarine and inland waters.Limnology and Oceanography 33:823–847.CrossRefGoogle Scholar
  18. Paerl, H. 1995. Coastal eutrophication in relation to atmospheric nitrogen deposition: Current perspectives.Ophelia 41:237–259.Google Scholar
  19. Paerl, H. 1997. Coastal eutrophication and harmful algal blooms: Importance of atmospheric deposition and groundwater as “new” nitrogen and other nutrient sources.Limnology and Oceanography 42:1154–1112.CrossRefGoogle Scholar
  20. Ryther, J. andW. Dunstan. 1971. Nitrogen, phosphorus and eutrophication in the coastal marine environment.Science 171:1008–1112.CrossRefGoogle Scholar
  21. Stanford, G., S. Dzienia, andR. V. Pol. 1975. Effect of temperature on denitrification rates in soils.Soil Science Society of America Proceedings 39:867–870.CrossRefGoogle Scholar
  22. U.S. Environmental Protection Agency. 1980. Design manual: Onsite wastewater treatment and disposal systems. Publication Number 625/1-80-012. Office Water Program Operations and Office of Research and Development, Washington, D.C.Google Scholar
  23. Valiela, I. andJ. E. Costa. 1988. Eutrophication of Buttermilk Bay, a Cape Cod coastal embayment: Concentrations of nutrients and watershed nutrient budgets.Environmental Management 12:539–553.CrossRefGoogle Scholar
  24. Valiela, I., J. E. Costa, K. Foreman, J. M. Teal, B. Howes, andD. Aubrey. 1990. Transport of groundwater-borne nutrients from watersheds and their effects on coastal waters.Biogeochemistry 10:177–197.CrossRefGoogle Scholar

Copyright information

© Estuarine Research Federation 2003

Authors and Affiliations

  • Mark S. Castro
    • 1
  • Charles T. Driscoll
    • 2
  • Thomas E. Jordan
    • 3
  • William G. Reay
    • 4
  • Walter R. Boynton
    • 5
  1. 1.Appalachian LaboratoryFrostburg
  2. 2.Department of Civil and Environmental EngineeringSyracuse UniversitySyracuse
  3. 3.Smithsonian Environmental Research CenterMarylandEdgewater
  4. 4.College of William and MaryVirginia Institute of Marine ScienceGloucester Point
  5. 5.Center for Environmental Science, Chesapeake Biological LaboratoryUniversity of MarylandSolomons

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