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<br />:-
<br />I
<br />.
<br />
<br />iple regression techniques to water quality data
<br />from the Green River basin. First, since existing
<br />data were on hand or readily available from pub-
<br />lished sources, no field work was required, red-
<br />ucing costs. This is not a trivial advantage con-
<br />sidering the large basin area.
<br />
<br />Secondly, from the results of the multiple
<br />regression analyses, we have a smaller set of basin
<br />parameters to investigate if we wish to determine
<br />cause-effect relations between attributes of the
<br />drainage and water quality. Multiple regression is
<br />an associative technique: simply becaus~ an attri-
<br />bute is associated with a water quality parameter
<br />does not mean that a change in the attribute will
<br />necessarily cause a change in the parameter. This
<br />nomination of important parameters is also a non-
<br />trivial advantage given that we found,from exist-
<br />ing data, 164 basin attributes.
<br />
<br />Thirdly, if we assume a cause-effect relation-
<br />ship between basin a~tes and water quality,
<br />and if the models have been tested and verified, we
<br />may use them to predict changes in water quality
<br />from changes in the basin attributes. this is not
<br />useful for relatively non-static basin attributes.
<br />The area of the drainage underlain by Cretaceous
<br />rock is not as likely to change as the area under
<br />different land cover. We must note that the three
<br />models we propose have not yet been tested or ver-
<br />ified: they should not be used as predictive equa-
<br />tions.
<br />
<br />e
<br />
<br />Finally, the water quality database for the
<br />portion of the Green River basin we studied was,
<br />compared by Lystrom et al., very sparse. In order
<br />to get 18 stations, two less than the minimum they
<br />recommend, we had to liberalize our criteria of
<br />choice twice. We increased the temporal width of
<br />the study from 10 years to IS, and reduced the
<br />proportion of years for which we required at least
<br />one data point from 10 to 7. Lystrom, et ale also
<br />extrapolated the data from a single year with at
<br />least 10 sepsona11y spaced samples to their entire
<br />10-year study. In the arid and semi-arid West,
<br />where year-to-year variation in precipitation can
<br />be significant, we did not feel that extrapolating
<br />a single year of data to the entire study period
<br />was wise. We feel that the scarcity of water qual-
<br />ity data found in this study would be typical of
<br />other western drainages with low human population
<br />densities and little cropland agriculture.
<br />
<br />LITERATURE CITED
<br />
<br />e
<br />
<br />Anderson, S.H., and'D.B. Inkely. 1984. Wyoming land
<br />cover map. Wyoming Cooperative Fish and Wildlife
<br />Unit, University of Wyoming, Laramie, WY.
<br />DeLong, Lewis L. 1977. An analysis of salinity in
<br />streams of the Green River basin, Wyoming.
<br />U.S. Geological Survey Water-Resources Invest-
<br />igations $77-103. 32pp. USGS Water Resources
<br />Division, Cheyenne, WY.
<br />Edwards, Allen L. 1979. Multiple regression and
<br />the analysis of variance and covariance. 212
<br />pp. W.H. Freeman and Co., San FranCisco, CA.
<br />
<br />205
<br />
<br />Fannin, Timothy E. 1983. Wyoming lake classific~-
<br />tion and survey, volume 1. 226pp. Wyoming G...1;
<br />and Fish Department, Cheyenne, WY.
<br />Hull, C. Hadlai, and Norman H. Nie. 1981. SPSS Up.
<br />date 7-9: new procedures and facilities for
<br />releases 7-9. 402pp. McGraw-Hill Book Co~pany
<br />New York, NY.
<br />Lowers, A.R., 1960. Climate of Wyoming. Climato-
<br />graphy of the United States 1160-48. U.S.
<br />Depart~ent of Commerce, Washington, DC.
<br />Lotus Development Corporation. 1983. Lotus 123.
<br />Lotus 'Development Corporation, Cambridge, ~.A.
<br />Lystrom, David J., Frank A. Rinella, DavidA. Rickert
<br />and Lisa Zimmerman. 1978. Multiple regression
<br />modeling approach for regional water quality
<br />management. EPA-600/7-78-198. 60pp. Environ-
<br />mental Research Laboratory, Athens, GA.
<br />Milliken, George A. and Dallas E. Johnson. 1984.
<br />The analysis of messy data, volume 1: de-
<br />signed experiments. 473pp. Lifetime Learning
<br />Publications, Belmont, CA.
<br />Munn, Larry. 1984. Personal-correspondence.
<br />Department of Plant Science, University of
<br />Wyoming, Laramie, WY.
<br />Nie, Norman H., C. Hadlai Hull, Jean G. Jenkins,
<br />Karin Steinbrenner, and Dale H. Brent. 1975.
<br />SPSS: statistical package for the social
<br />sciences. 675pp. McGraw-Hill Book Company, New
<br />York, NY.
<br />'Parker, Michael, Wayne A. Hub~rt, and Steve Greb.
<br />1984. A preliminary assessment of eutrophica-
<br />tion in Flaming Gorge Reservoir, Denise
<br />Bierley, ed. 46pp.+app. Wyoming Water Devel-
<br />opment Commission, Cheyenne, WY, and Wyoming
<br />Water Research Center, Laramie, WY.
<br />Southwestern Wyoming Water Quality Planning Assoc-
<br />iation. 1978. Clean water report for south-
<br />western Wyoming, 313pp. CH2M Hill, Denver, CO.
<br />U.S. Environmental Protection ~gency. 1977. Report
<br />on Flaming Gorge Reservoir, Sweetwater County,
<br />Wyoming and Daggett County, Utah, EPA Region
<br />VIII. National Eutrophication Survey Working
<br />Paper 1/885.
<br />U.S. Bureau of the Census. 1981. 1980 census of the
<br />population: vol. 1: characteristics of the
<br />population: chapter A: number of inhabitants,
<br />part 52 Wyoming. PC80-11-A52. U.S. Bureau of
<br />the Census, Washington, DC.
<br />Wagner, John. 1984. Personal correspondence.
<br />Wyoming Department of Environmental Quality,
<br />Cheyenne, WY.
<br />Welder, George E. 1968. Ground-water reconnaissance
<br />of the Green River basin--southwestern Wyoming.
<br />Hydrologic Investigations Atlas HA-290. U.S.
<br />Geological Survey, Washington, DC.
<br />, and Laurence J. McGreevy. 1966. Ground-
<br />-----water reconnaissance of the Great Divide and
<br />Washakie basins and some adjacent areas,
<br />southwestern Wyoming. Hydrologic Investiga-
<br />tions Atlas HA-219, reprinted 1981. U.S. Geo-
<br />logical Survey, Washington, DC.
<br />Whitcomb, Harold A. and Martin E. Lowry. 1968.
<br />Ground-water resources and geology of the Wind
<br />River basin area, central Wyoming. Hydrologic
<br />Investigations Atlas HA-270. U.S. Geological
<br />Survey, W..hinaton, DC. ~ .,
<br />.,
<br />.JIll'
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