McCormick Creek. Both sites on McCormick Creek suffer from minor sedimentation 

 and organic loading. In addition, the upper site supported a few teratological diatom cells and 

 the lower site supported large percentages of Fragilaria vaucheriae, Nitzschia archibaldii, and 

 Synedra acus, all eutraphentic species that indicate elevated concentrations of inorganic 

 nutrients. Nevertheless, both sites had good biological integrity and provided full support of 

 aquatic life uses. The two sites on McCormick Creek shared 43% of their diatom assemblages, 

 which indicates only minor environmental change from one site to the next. 



Big Blue Creek. Aside from a few teratological cells, diatom metrics suggest excellent 

 biological integrity, no impairment, and full support of aquatic life uses in Big Blue Creek. 

 Although the siltatiori index was just below the threshold for minor impairment, this site did 

 support a large percentage (22%) of Planothidium species, which are adapted to living attached 

 to sand grains. This site had the largest pollution index among streams in the sample set, which 

 suggests that it receives less organic loading than the other sites. 



Josephine Creek. Diatom metrics indicate minor impairment from sedimentation and 

 organic loading at the upper site, which also supported a few teratological diatom cells. This site 

 supported a large percentage (38%) of Planothidium species, which are adapted to living on sand 

 grains. Moreover, the upper site on Josephine Creek had the lowest diatom species richness and 

 diversity values of all the sites in the sample set. This low diversity and species richness may be 

 due, in part, to substrate instability. A large percentage of Diatoma mesodon — a cold-water 

 stenotherm — indicates consistently cold water temperatures at this site. 



A large percentage of motile diatoms (46%) suggest moderate impairment from 

 sedimentation at the downstream site on Josephine Creek. This site also had the lowest 

 pollution index (2.27), which indicates minor to moderate impairment from organic loading. The 

 dominant species at the lower site was Fragilaria vaucheriae, an eutraphentic species that 

 indicates elevated concentrations of inorganic nutrients. The two sites on Josephine Creek 

 shared 29% of their diatom assemblages, which suggests that there was a moderate change in 

 environmental conditions between them. 



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