Record Display for the EPA National Library Catalog


Main Title Watershed Nitrogen and Phosphorus Balance: The Upper Potomac River Basin.
Author Jaworski, N. A. ; Groffman, P. M. ; Keller, A. A. ; Prager, J. C. ;
CORP Author Environmental Research Lab., Narragansett, RI. ;Rhode Island Univ., Kingston. Dept. of Natural Resources Science. ;Rhode Island Univ., Narragansett. Marine Ecosystems Research Lab.
Publisher c1992
Year Published 1992
Report Number EPA/600/J-93/199 ;ERLN/CONTRIB-1083;
Stock Number PB93-199586
Additional Subjects Potomac River Basin ; Nitrogen ; Phosphorus ; Mass balance ; Water pollution ; Pollutant sources ; Point sources ; Agricultural wastes ; Air water interactions ; Watersheds ; Loading rates ; Nutrients ; Reprints ;
Library Call Number Additional Info Location Last
NTIS  PB93-199586 Some EPA libraries have a fiche copy filed under the call number shown. 07/26/2022
Collation 15p
Nitrogen and phosphorus mass balances were estimated for the portion of the Potomac River basin watershed located above Washington, D.C. The total nitrogen (N) balance included seven input source terms, six sinks, and one 'change-in-storage' term, but was simplified to five input terms and three output terms. The phosphorus (P) baance had four input and three output terms. The estimated balances are based on watershed data from seven information sources. Major sources of nitrogen are animal waste and atmospheric deposition. The major sources of phosphorus are animal waste and fertilizer. The major sink for nitrogen is combined denitrification, volatilization, and change-in-storage. The major sink for phosphorus is change-in-storage. River exports of N and P were 17% and 8%, respectively, of the total N and P inputs. Over 60% of the N and P were volatilized or stored. The major input and output terms on the budget are estimated from direct measurements, but the change-in-storage term is calculated by difference. The factors regulating retention and storage processes are discussed and research needs are identified. (Copyright (c) 1992 Estuarine Research Federation.)