Author(s): Karl-Erich Lindenschmidt; Nasim Hosseini
Keywords: No Keywords
Abstract: A global sensitivity analysis was carried out on a water quality model to investigate the sensitivity of nutrient transformation processes on surface water quality. Water Quality Analysis Simulation Program (WASP) 7 was utilized to model the water quality of the upper Qu’Appelle River in Saskatchewan, Canada. The river completely freezes over during winter; hence, the sensitivity analysis was carried out seasonally, for winter and summer, to account for the influence of ice-covered conditions on nutrient transformations. Model calibration and validation were based on the measured data at two water quality stations along the river. The results show good agreement between model prediction and measured data. Using a global sensitivity analysis based on a Monte Carlo analysis, it was found that there was a seasonal trend in the sensitivity of parameters. Nitrogen transformation processes were more sensitive under the ice-on condition, while dissolved oxygen parameters showed higher sensitivity in the ice-off period. Sensitivities of the model parameters were slightly higher at the downstream station.