Table 4. Percent abundance of major diatom species^ and values of selected diatom association metrics for 

 periphyton samples collected from Sullivan Creek and Skyland Creek in 2002. Underlined values 

 indicate minor stress; bold values indicate moderate stress; underlined and bold values indicate 

 severe stress; all other values indicate no stress and full support of aquatic life uses w/hen compared 

 to criteria for mountain streams in Table 2. Stress may be natural or antfiropogenic (see text) 



^A major diatom species accounts for 5.0% or more of the cells at one or more stations in a sample set. 

 ^(Organic) Pollution Tolerance Class (Lange-Bertalot 1979): 1 = most tolerant; 2 = tolerant; 3 = sensitive. 

 ^Percent Community Similarity (Whittaker 1952) when compared to the diatom assemblage at the adjacent 

 upstream station. 



