Biogeochemistry

, Volume 57, Issue 1, pp 267–293

Where did all the nitrogen go? Fate of nitrogen inputs to large watersheds in the northeastern U.S.A.

  • N van Breemen
  • E.W. Boyer
  • C.L. Goodale
  • N.A. Jaworski
  • K. Paustian
  • S.P. Seitzinger
  • K. Lajtha
  • B. Mayer
  • D. van Dam
  • R.W. Howarth
  • K.J. Nadelhoffer
  • M. Eve
  • G. Billen
Article

DOI: 10.1023/A:1015775225913

Cite this article as:
van Breemen, N., Boyer, E., Goodale, C. et al. Biogeochemistry (2002) 57: 267. doi:10.1023/A:1015775225913

Abstract

To assess the fate of the large amounts of nitrogen (N) brought into the environment by human activities, we constructed N budgets for sixteen large watersheds (475 to 70,189 km2) in the northeastern U.S.A. These watersheds are mainly forested (48–87%), but vary widely with respect to land use and population density. We combined published data and empirical and process models to set up a complete N budget for these sixteen watersheds. Atmospheric deposition, fertilizer application, net feed and food inputs, biological fixation, river discharge, wood accumulation and export, changes in soil N, and denitrification losses in the landscape and in rivers were considered for the period 1988 to 1992. For the whole area, on average 3420 kg of N is imported annually per km2 of land. Atmospheric N deposition, N2 fixation by plants, and N imported in commercial products (fertilizers, food and feed) contributed to the input in roughly equal contributions. We quantified the fate of these inputs by independent estimates of storage and loss terms, except for denitrification from land, which was estimated from the difference between all inputs and all other storage and loss terms. Of the total storage and losses in the watersheds, about half of the N is lost in gaseous form (51%, largely by denitrification). Additional N is lost in riverine export (20%), in food exports (6%), and in wood exports (5%). Change in storage of N in the watersheds in soil organic matter (9%) and wood (9%) accounts for the remainder of the sinks. The presence of appreciable changes in total N storage on land, which we probably under-rather than overestimated, shows that the N budget is not in steady state, so that drainage and denitrification exports of N may well increase further in the future.

Copyright information

© Kluwer Academic Publishers 2002

Authors and Affiliations

  • N van Breemen
    • 1
  • E.W. Boyer
    • 2
  • C.L. Goodale
    • 3
  • N.A. Jaworski
    • 4
  • K. Paustian
    • 5
  • S.P. Seitzinger
    • 6
  • K. Lajtha
    • 7
  • B. Mayer
    • 8
  • D. van Dam
    • 9
  • R.W. Howarth
    • 10
  • K.J. Nadelhoffer
    • 11
  • M. Eve
    • 6
  • G. Billen
    • 12
  1. 1.Laboratory of Soil Science & Geology and Wageningen Institute for Environment and Climate ResearchWageningen UniversityWageningenthe
  2. 2.College of Environmental Science and ForestryState University of New YorkSyracuse
  3. 3.Department of Plant BiologyCarnegie Institution of WashingtonStanford
  4. 4.US EPAWakefield
  5. 5.Natural Resource Ecology LaboratoryColorado State UniversityFort Collins
  6. 6.Institute of Marine and Coastal SciencesRutgers UniversityNew Brunswick
  7. 7.Department of Botany & Plant PathologyOregon State UniversityCorvallis
  8. 8.Department of Geology & GeophysicsUniversity of CalgaryCanada
  9. 9.Laboratory of Soil Science & Geology and Wageningen Institute for Environment and Climate ResearchWageningen UniversityWageningen, theNetherlands
  10. 10.Department of Ecology & Evolutionary BiologyCornell UniversityIthaca
  11. 11.Marine Biological LaboratoryThe Ecosystems CenterWoods Hole
  12. 12.Free University of BrusselsBelgium