MULLET LAKE WATER QUALITY TESTS, CHEBOYGAN COUNTY
SUMMER, 1992


TIM NINKE

Department of Biology and Chemistry

Lake Superior State Urnversity

Sault Ste.Marie,  Michigan 49783 U.S.A.


Abstract:	Seven water quality tests were performed on Mullet Lake in June, July, and
August of 1992. Samples were obtained at three levels: 1) surface, 2) lOM and
3) 20M. The water quality tests performed were temperature, dissolved oxygen, pH,
turbidity, quality, nitrate Nitrogen, and ortho-phosphate. Lineai regression were
used to obtain the best line that would fit the data from 1966 to 1992 for each test
performed. This line was then tested at p=O.05 level ofsigiiificance to see if the slope
ofthe line was significantly different from zero. If the slope was significantly
different from zero, this would indicate that a significant change had occulTed in a
water quality parameter over time. A significant increase was found at the lOM and
20M depths for the nitrate nitrogen tests from 1972-1992. A significant decrease
was found for pH at the surface and 1OM levels from 1971 to 1992. No significant
change was found for dissolved oxygen, turbidity, ortho-phosphate, and aikaljnity for
any of the test levels.


SELECTED REFERENCES

M~IIer,	J. B., and T. Thompson 1970. Compilation of Data for Michigan Lakes. United
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Cesceri, L.S., M.H. Franson, A.E. Greenberg, and R. R. Trusses. 1985. Standard
Methods. American Public Health Association, APHA  16:400-429