Record Display for the EPA National Library Catalog


OLS Field Name OLS Field Data
Main Title Modeling Impacts of Acid Precipitation for Northeastern Minnesota.
Author Schnoor, J. L. ; Palmer, W. D. ; Glass, G. E. ;
CORP Author Environmental Research Lab.-Duluth, MN. ;Iowa Univ., Iowa City. Div. of Energy Engineering.
Year Published 1985
Report Number EPA/600/D-85/035;
Stock Number PB85-170181
Additional Subjects Water pollution ; Mathematical models ; Transport of properties ; Air pollution ; Minnesota ; Northeast Region(United States) ; Assessments ; Hydrology ; Geochemistry ; Lakes ; Streams ; Acid rain ; Northeast Region(Minnesota) ; Path of pollutants ; Ecosystem ; Wet deposition ; Dry deposition
Library Call Number Additional Info Location Last
NTIS  PB85-170181 Most EPA libraries have a fiche copy filed under the call number shown. Check with individual libraries about paper copy. 06/21/1988
Collation 42p
The acidification of lakes and streams due to acid precipitation has been documented in southern Sweden and Norway, the northeastern United States and southern Ontario. Geochemistry and regional lithology are recognized to be important factors in the susceptibility of lake ecosystems to acid precipitation. Local soils, glacial deposits and bedrock undergo biological and chemical weathering reactions to consume protons and release base cations - the greater is the total alkalinity production in the watershed, the greater is the capacity to neutralize acid loadings. Acid loadings are composed of wet and dry deposition to a watershed, and these are also important factors in the degree of acidification of lakes. A schematic of the trickle-down model, which is used in acid precipitation assessments, is shown. The hydrology and geochemistry of the watershed determine the chemical weathering rate and thus are key factors in the susceptibility of lakes to acidification. In this chapter, lakes in northeastern Minnesota serve as case studies, where igneous bedrock and a lack of calcareous overburden are sufficient to classify the region as sensitive to acid rain. The volume-weighted acidity of precipitation pH ranges 4.6-4.85. These are threshold cases where it is not certain whether present acid loadings are acidifying lakes.