The relationship of turbidity and organic matter to bacterial productivity and biomass in a small Texas lake.

The relationship between water turbidity and bacterial cell synthesis, specific production and bacterial productivity was investigated in a small Texas reservoir. Sampling dates were selected to include a variety of water turbidities. Bacterial cell synthesis calculated from rates 3 7 of H-thymidine incorporation ranged from 1.97X10 to 4.79X10 cell 1 h . Specific production ranged from 0.006 to 0.03 ug C ug C”^ 1“^ h”^. Bacterial production varied between 0.23 and 0.83 ug C l”"*" h”^. Multiple regression analysis showed that turbidity explained 63.6% of the variation in cell synthesis. When combining turbidity with the biomass of the particle-attached bacteria 82% of the changes were explained and 95.6% were explained when combining turbidity, attached cell biomass and total organic carbon. Changes in specific production were determined primarily by the turbidity (r=.76), combining turbidity with dissolved organic carbon the variation explained was 90.3%. The absolute bacterial production changes were not explained by any of the environmental variables measured during the study.