PERIPHYTON 

 Periphyton Methods 



Periphyton samples were collected from each of the three German Gulch 

 Inventory sites by scraping natural stream bottom materials (primarily gravel 

 and larger rock substrates) with a sharp utensil. The scrapings were then 

 immediately transferred on site to small, labelled vials, and they were 

 preserved with Lugol's solution for transport and storage until laboratory 

 analyses could be undertaken of the gulch's periphyton communities. 



The laboratory evaluations of the natural substrate scrapings from the 

 German Gulch stations were separately initiated by first removing the 

 obviously non-diatomaceous plant matter from the vials for a microscopic 

 taxonomic examination and generic identification. As an added step, temporary 

 wet mounts of a small portion of the less well-defined part of the same 

 collections were prepared to further check for the presence of any soft-bodied 

 algal filaments and cells. This accessory manipulation led to the initiation 

 of supplemental generic identifications, and qualitative abundance estimates 

 were also made for each of the soft-bodied algal forms that were encountered 

 in the three project samples. Subsequently, permanent mounts were prepared 

 from the scrapings from each of the sites for use in conducting the diatom 

 species and variety taxonomic assessments and for use in completing the diatom 

 percent relative abundance (PRA) tabulations. 



To prepare the permanent slides for each of the project's periphyton 

 collections, aliquots of the collected periphytic materials from the three 

 sites were separately oxidized and treated in accord with the procedures that 



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