Environmental Modelling of Hydrological Systems

Sammanfattning: Global problems such as atmospheric change, acid rain, and water pollution in surface and subsurface environments dominate discussions of world environmental problems. In this thesis the roles of hydrologic processes and hydrogeochemical processes are investigated through development, modification, and application of models for addressing point and non-point source contamination of water. The movements of pollutants and water are described. A hydrological model was applied to Northeast Pond River watershed to understand climate change effects in the watershed. Four watershed acidification models were applied. The computed hydrogen ion was used to estimate acidic events, magnitude of hydrogen ion, and duration using a stochastic model. There exist uncertainties in hydrologic models due to imperfect knowledge of processes controlling water quality as well as errors in data. Monte Carlo, first order, and inverse method analyses were used to assess uncertainty in water quality models. SUTRA and inverse SUTRA models were applied to locate ground water discharge areas to St. Clair River, calculate discharge rates, and hydrogeologic parameters. A sediment contamination model was developed and applied to Great Lakes sediment data to estimate transport parameters. It was then coupled with fatty acid data and results were compared with observed data. A contaminant transport model was developed and applied to two North American steams to compute stream water concentration. A hydrological model was coupled with water quality models and RAISON expert system and applied to Canadian watersheds. Digital satellite data was used to locate ground water discharge and recharge areas in the watershed.