species at both sites were not motile, indicating that they were not adapted to withstanding high 

 loads of sediment or aggrading substrates. Most diatoms at both sites indicated circumneutral 

 (pH -7) and fresh-brackish (TDS <900 mg/L) waters. The majority of diatoms at both sites are 

 autotrophs, meaning that they require inorganic nitrogen for their nutrition but they also tolerate 

 elevated concentrations of organically-bound nitrogen. Most diatoms at the upper site were not 

 classified with regard to their oxygen requirements, but the majority of diatoms at the lower site 

 require close to 100% saturation of dissolved oxygen. Most diatoms at the upper site were 

 unclassified with regard to saprobity, but most diatoms at the lower site indicate 70-85% oxygen 

 saturation and BOD levels of 2-4 mg/L. The majority of diatoms at both sites tolerate a wide 

 range of trophic conditions ranging from oligotrophic to eutrophic (Van Dam et al. 1994). 



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