The impact of depressed pH and elevated aluminum concentrations on specific dynamic action in Somatochlora cingulata...

Differences in oxygen consumption attributable to apparent specific dynamic action (SDA) were measured in relation to feeding level in the dragonfly naiad Somatochlora cingulata exposed to low pH and sublethal aluminum concentration plus low pH. The average increases in respiration among the treatments following feeding were 50-60% that of controls. The average treatment peak height ratios (post/prefeeding respiration rates) were proportionately reduced and not significantly different from the average controls indicating that the resting metabolism, rather than SDA, was reduced.