that caused the low diversity in the South Fork was natural, 

 rather than cultural, in origin. 



Besides Nitzschia frustulum, the other major diatom in the 

 South Fork of Lodgepole Creek was Synedra famelica (Table 5) . In 

 the Southern Fort Union Coal Region of Montana, this diatom 

 prefers brackish, extremely hard waters with large concentrations 

 of sulfate and small amounts of suspended sediment and turbidity 

 (Bahls et al . 1984) . Overall, the major diatoms in the South 

 Fork of Lodgepole Creek indicate cool, clear waters of moderate 

 conductivity and low levels of suspended sediment and siltation. 



LITERATURE CITED 



APHA. 1998. Standard Methods for the Examination of Water and 

 Wastewater. 20th Edition. American Public Health 

 •Association, Washington, D.C. 



Bahls, L.L. 1979. Benthic diatom diversity as a measure of 

 water quality. Proc . Mont. Acad. Sci . 38:1-6. 



Bahls, L.L. 1993. Periphyton Bioassessment Methods for Montana 

 Streams (Revised) . Montana Department of Health and 

 Environmental Sciences, Helena. 



Bahls, L.L., Bob Bukantis, and Steve Tralles. 1992. Benchmark 



Biology of Montana Reference Streams. Montana Department of 

 Health and Environmental Sciences, Helena. 



Bahls, L.L., E.E. Weber, and J. 0. Jarvie . 1984. Ecology and 

 Distribution of Major Diatom Ecotypes in the Southern Fort 

 Union Coal Region of Montana. U.S. Geological Survey 

 Professional Paper 1289, U.S. Government Printing Office, 

 Washington . 



Barbour, M.T., J. Gerritsen, B.D. Snyder, and J.B. Stribling. 



1999. Rapid Bioassessment Protocols for Use in Streams and 

 Wadeable Rivers: Periphyton, Benthic Macroinvertebrates and 

 Fish. Second Edition. EPA/841-B-99- 002 . U.S. EPA, Office 

 of Water, Washington, D.C. 



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