Estimation of Whole Pond Respiration Rate

A regression application of the whole pond respiration–diffusion (WPRD) model to overnight observations of dissolved oxygen concentration (DO) was introduced as a new method to estimate whole pond respiration rate. A new modification of the Welch procedure was also presented. These two techniques were compared with the tangent method for whole pond respiration rate estimation. The tangent method required fitting a quadratic curve to observed DO; and then calculating the slope of the tangent line to the curve at the time the curve reached 100% saturation of DO. When the quadratic was fitted to DO observed during both day and light, the tangent method often yielded inaccurate estimates of whole pond respiration rate. Estimates by the tangent method were sensitive to the time at which 100% saturation of DO occurred. The WPRD model regression and the modified Welch procedure were recommended to estimate whole pond respiration rate.