Effects of Solar Radiation on the Dynamics of Dissolved Oxygen in Channel Catfish Ponds

Abstract The daytime increase in dissolved oxygen (DO) concentration of pond waters may be estimated from solar radiation, chlorophyll a concentration, and percentage O2 saturation at dawn (coefficient of multiple determination, R2 = 0.83), or from solar radiation, Secchi disk visibility, and percentage O2 saturation at dawn (R2 = 0.80). A computer simulation model for predicting the effects of cloudy weather (low solar radiation) on DO depletion was developed for channel catfish ponds. The model incorporates the equation for estimating daytime DO increase from solar radiation and Secchi disk visibility with components for estimating the nighttime decline in DO from respiration by the plankton, fish, and benthic communities, and the gains or losses from diffusion. Results from the study demonstrated that the combination of dense plankton blooms and low levels of light intensity were closely related to low concentrations of DO.