Record Display for the EPA National Library Catalog


OLS Field Name OLS Field Data
Main Title Trends in Catskill Stream Water Quality: Evidence from Historical Data.
Author Stoddard, J. L. ;
CORP Author Corvallis Environmental Research Lab., OR. ;New York City Dept. of Environmental Protection, Valhalla. Kensico Lab.
Publisher c1991
Year Published 1991
Report Number EPA/600/J-92/091;
Stock Number PB92-153832
Additional Subjects Water quality data ; Streams ; Acidification ; Water pollution sampling ; Deposition ; Trends ; Catskill Mountains ; Air pollution ; Air water interactions ; Cations ; Nitrates ; pH ; Acid neutralizing capacity ; Concentration(Composition) ; Specific conductivity ; Environmental surveys ; Reprints ; Calcium magnesium
Library Call Number Additional Info Location Last
NTIS  PB92-153832 Most EPA libraries have a fiche copy filed under the call number shown. Check with individual libraries about paper copy. 08/28/1992
Collation 12p
Historical data for large streams in the Catskill Mountains indicate that acidic deposition has significantly influenced water quality, but that this effect is most observable in early (pre-1945) data, and consists primarily of increased base cation (CaMg) concentrations. More recent data suggest that landscape disturbance currently exerts a stronger influence on acid/base status of large streams than does acidic deposition, resulting in increases in both CaMg and acid-neutralizing capacity (ANC). Estimates of SO4(2-) concentration indicate that SO4(2-) is a conservative ion in the Catskills, and stream water concentrations have decreased since reaching maximum values around 1970, consistent with temporal trends in emissions and deposition in the northeastern United States. Nitrate concentrations, on the other hand, have increased substantially in all but one stream in the past two decades, independent of any change in nitrogen deposition in the region; changes in the capacity of watersheds to retain nitrogen are hypothesized as causes of increased stream water NO3(-). In small, undisturbed streams, increases in NO3(-) and decreases in CaMg appear to offset the effects of reduced SO4(2-), and lead to decreasing trends in ANC. (Copyright (c) 1991 by the American Geophysical Union.)