||Historical review of water quality and climatic data from Chesapeake Bay with emphasis on effect of enrichment
Heinle, Donald. ;
D'Elia, Christopher F. ;
Taft, Jay L. ;
Wilson, John S. ;
||Maryland Univ., Solomons. Chesapeake Biological Lab.;Environmental Protection Agency, Annapolis, MD. Chesapeake Bay Program.
||U.S. Environmental Protection Agency, Center for Environmental Research Information,
||EPA-600/3-82-083; UMCEES-80/15-CBL; EPA-R-806189010; EPA/CBP-TR-002E
Water quality--Chesapeake Bay ;
Water pollution ;
Chesapeake Bay ;
Climatic changes ;
Dissolved gases ;
Marine fishes ;
Biological productivity ;
Coliform bacteria ;
Patuxent River ;
Potomac River ;
||Region 3 Library/Philadelphia, PA
||Region 10 Library/Seattle,WA
||Most EPA libraries have a fiche copy filed under the call number shown. Check with individual libraries about paper copy.
||239 p. ; 28 cm.
Review of the available data on water quality in Chesapeake Bay has revealed changes over recent decades caused by enrichment with nutrients. In the upper and middle bay, and several tributaries, concentrations of algae present during the summer months have increased since the mid 1960's. There have been decreases in the clarity of the water associated with increased algal stocks. Nutrient concentrations have also increased, phosphorus more notably so than nitrogen. In some of the tributaries increased algal production has led to reduced concentrations of oxygen below the halocline in the middle part of the estuary. Oxygen concentrations in the open bay have not changed greatly with the possible exception of extreme conditions, as during periods of extensive ice cover. Since 1969 or 1970, however, stocks of many anadromous species and marine spawners representing higher tropic levels have declined to new long-time lows.