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Soap Creek. Minor impairment from sedimentation was indicated at both sites on Soap 

 Creek. Planothidium species were dominant at both sites. Minor impairment from organic 

 loading was indicated at site 01 and borderline impairment from organic loading was noted at 

 site 02. Major diatom species indicate slower current velocities at site 01 and more physical 

 disturbance at site 02. Abnormal cells were not observed at either site and the two sites 

 supported very similar diatom floras. 



MacLean Creek. Diatom metrics indicate minor impairment from sedimentation and 

 organic loading in MacLean Creek. The dominant diatom species at this site {Planothidium 

 lanceolatum) is adapted to living attached to grains of sand. Another major species at this site 

 {Nitzschia linearis) is highly motile and adapted to living on shifting substrates composed of fine 

 sediments. A few abnormal diatom cells were observed in the sample from MacLean Creek. 



Grose Creek. Diatom metrics indicate minor impairment from organic loading and 

 borderline moderate impairment from sedimentation in Grose Creek. Planothidium species 

 dominated the diatom assemblage of Grose Creek, as they did in MacLean Creek. Nitzschia 

 linearis was also a major species in Grose Creek. No abnormal diatom cells were observed in 

 the sample from Grose Creek. 



Lost Creek. A large number of highly motile diatoms indicates severe impairment 



from sedimentation at site 01 on Lost Creek. In addition, the pollution index value at site 01 

 approached the criterion for moderate impairment from organic loadmg. The dominant species 

 here was Nitzschia inconspicna. Besides being highly motile, this species is eutraphentic and a 

 facultative nitrogen heterotroph. Navicula minima was another major species at site 01. This 

 species is also a motile, eutraphentic, nitrogen heterotroph. A few abnormal cells were observed 

 in the sample collected at site 1 . 



Much less organic loading and sedimentation were observed at site 02, where the 

 pollution index indicated no impaiiinent and the sedimentation index indicated only minor 

 impairment. Cocconeis placentula. Planothidium species, and Rhoicosphenia abbreviata ^| 



15 



