Seasonal and spatial distribution of bacterial biomass and the percentage of viable cells in a reservoir of Alabama

Spatial community dynamics of bacterioplankton were evaluated along the length of the former stream channel of Elledge Lake, a small reservoir in western Alabama. The reservoir was strongly stratified from April to October with up to a 10°C temperature difference across the 1 m deep metalimnion. Bacterial biomass was highest during late summer, with a general pattern of increasing abundance from the inflowing river (∼10 μg C l−1) to the dam (∼20–30 μg C l−1). Bacterial numbers also increased following a >10-fold increase in turbidity associated with a major precipitation event, although only ∼10% of these cells were viable. The percentage of viable cells generally increased through the stratified period with 50–70% viable cells in late summer. Overall, an average of 38% of bacterial cells were viable, with a range from