A SPARROW (SPAtially Referenced Regressions On Watershed Attributes) total nitrogen model was calibrated (2000-2002) by using data from the Tar, Neuse, and Cape Fear basins in eastern North Carolina. The SPARROW modeling approach has three main features:
A geographic information system is used to manage data about nitrogen sources, instream nitrogen flux measured at monitoring sites, characteristics of the terrestrial landscape, and the location and connectivity of a waterhsed's stream reach.
The statistical basis of SPARROW provides an objective means of specifiying a relation between nitrogen flux and the sources and losses of nitrogen within the watershed. The model specifies that instream nitrogen flux is a function of a nonlinear relation between nitrogen sources, such as point sources, atmospheric deposition, and agricultural and developed land use, land-delivery processes, and instream nitrogen processing.
The SPARROW model makes explicit use of information that can be derived from the stream reach network about the spatial relation among nitrogen fluxes, sources, landscape characteristics, and stream characteristics.
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McMahon, Gerard, and Woodside, M.D., 1997, Estimating a nutrient mass balance for major drainage areas of the Albemarle-Pamlico Drainage Basin, North Carolina and Virginia: Albemarle-Pamlico Estuarine Study Comprehensive Conservation and Management Plan Implementation Forum, June 5-6.
McMahon, Gerard, and Woodside, M.D., 1997, Nutrient mass balance for the Albemarle-Pamlico Drainage Basin, North Carolina and Virginia, 1990: Journal of the American Water Resources Association. v. 33, no. 3, June 1997, p. 573-589.
McMahon, Gerard, and Woodside, M.D., 1994, Nitrogen mass balance for major drainage areas of the Albemarle-Pamlico Drainage Basin, North Carolina and Virginia [abs.]: American Geophysical Union 1994 Fall Meeting, December 5-9, 1994, San Francisco, California, p. 229.
National USGS SPARROW pageU.S. Department of the Interior, U.S. Geological Survey