Summary: | Thesis (M.S.) University of Alaska Fairbanks, 1984 Very few seasonal studies of attached stream algae (periphyton) have been conducted in the arctic and subarctic. Periphyton were sampled for 13 months in Monument Creek, a second-order stream, and in the West Fork of the Chena River, a fourth-order stream near Fairbanks, Alaska. Seasonal changes in periphyton community structure, density (cells ∙ m-2), biovolume (μm3), total chlorophyll a (mg ∙ m-2), and physical and chemical factors were determined. Diatoms dominated the community throughout the year in number and biovolume. Mean annual periphyton density was moderately high in West Fork and mean annual biomass (as total chlorophyll a) was low in both West Fork and Monument Creek when compared to published subarctic and temperate stream literature values. It is significant that the winter periphyton community was active despite low light levels. Futhermore, it is suggested that a dramatic increase in total chlorophyll a content per cell in winter may indicate adaptation of these periphyton to low light levels. Alaska Cooperative Fishery Research Unit, Alaska Department of Fish and Game, Sport Fish Division
|