Simulation of lake-watershed systems I. Description and sensitivity analysis of the model

A practical lumped response watershed model has been developed to study lake-watershed systems in a Canadian prairie setting. The model is designed to utilize basic climatic, hydrological and physical data, that are normally available for lake studies, in order to simulate variations in lake water quality and level.The model has been used to examine the role that climatic, hydrological and physical variables play in controlling the hydrology and chemistry of prairie lakes. These analyses indicated that climatic parameters, such as precipitation, evaporation and temperature, play a dominant role in influencing lake levels and salinity of shallow lakes or those situated in small watersheds. The physical and chemical hydrology of large deep lakes or those located in a large watershed is primarily controlled by groundwater discharge and surface runoff. Physically altering the watershed may also produce significant changes to the lake chemistry and surface elevations.