Record Display for the EPA National Library Catalog


Main Title Ecology of the Second Trophic Level of Lakes Superior, Michigan, and Huron.
Author Swai, Wayland R. ; Olso, Theodore A. ; Odlau, Theron O. ;
CORP Author Minnesota Univ., Minneapolis. Water Resources Research Center.
Year Published 1970
Report Number WRRC-Bull-26; PHS-ES-00064-01; OWRR-A-011-MINN; 08665,; A-011-MINN(10)
Stock Number PB-199 838
Additional Subjects ( Ecology ; Lakes) ; ( Food chains ; Lakes) ; ( Plankton ; Ecology) ; Biological productivity ; Plankton ; Aquatic animals ; Aquatic plants ; Indicator species ; Aquatic biology ; Limnology ; Water resources ; Water pollution ; Great Lakes ; Eutrophication ; Lake Superior ; Lake Michigan ; Lake Huron
Library Call Number Additional Info Location Last
NTIS  PB-199 838 Some EPA libraries have a fiche copy filed under the call number shown. 07/26/2022
Collation 166p
A series of lake-long transect tows were made with the Continuous Plankton Recorder in Lakes Superior, Michigan and Huron, 1966-68. All tows were made at ten meters depth with either no. 60 mesh Grit Gauze or no. 15 mesh Silk Bolting cloth. Information was obtained on organism distribution in both space and time. The density and distribution of ecologically related groups in plankton indicate the relative tropic status of the bodies of water sampled. Lake Superior is the most oligotrophic, Lake Huron the most eutrophic and Lake Michigan more mesotrophic. A mean of 200 to 300 organisms per section was seen in Lake Superior; a range of 5,000 to 6,000 organisms per section was seen in Lake Michigan and from 20,000 to 21,000 organisms were observed from one year to another and from one season to another. Marked variations in both numbers and species of organisms were evident in the lakes. Limitations of the Continuous Plankton Recorder method are described. (WRSIC abstract)