Can't see the forest for the stream? In-stream processing and terrestrial nitrogen exports


Journal Article

There has been a long-term decline in nitrate (NO3-) concentration and export from several long-term monitoring watersheds in New England that cannot be explained by current terrestrial ecosystem models. A number of potential causes for this nitrogen (N) decline have been suggested, including changes in atmospheric chemistry, insect outbreaks, soil frost, and interannual climate fluctuations. In-stream removal of NO3- has not been included in current attempts to explain this regional decline in watershed NO3- export, yet streams may have high removal rates of NO3-. We make use of 40 years of data on watershed N export and stream N biogeochemistry from the Hubbard Brook Experimental Forest (HBEF) to determine (a) whether there have been changes in HBEF stream N cycling over the last four decades and (b) whether these changes are of sufficient magnitude to help explain a substantial proportion of the unexplained regional decline in NO3- export. Examining how the tempos and modes of change are distinct for upland forest and stream ecosystems is a necessary step for improving predictions of watershed exports. © 2005 American Institute of Biological Sciences.

Full Text

Duke Authors

Cited Authors

  • Bernhardt, ES; Likens, GE; Hall, RO; Buso, DC; Fisher, SG; Burton, TM; Meyer, JL; Mcdowell, WH; Mayer, MS; Bowden, WB; Findlay, SEG; Macneale, KH; Stelzer, RS; Lowe, WH

Published Date

  • January 1, 2005

Published In

Volume / Issue

  • 55 / 3

Start / End Page

  • 219 - 230

International Standard Serial Number (ISSN)

  • 0006-3568

Digital Object Identifier (DOI)

  • 10.1641/0006-3568(2005)055[0219:ACSTFF]2.0.CO;2

Citation Source

  • Scopus