Abstract for: Developing a simple dynamic simulation model of phosphorus in Lake Ontario

Food cycle creates a mechanism through which nutrients and other components of life are available for living organisms. Improper function of one component of the cycle may lead to emerging disruption in the life cycle of organisms. In this paper, the dynamic behavior of phosphorus was studied by considering three state variables: productive organisms (organic phosphorus), dead organisms (organic phosphorus) and inorganic phosphorus. The system dynamics model intelligibly provides information about changing state variables levels with respect to all interactions and feedbacks. The model was applied to Lake Ontario and run for a year with daily time steps. The model demonstrates acceptable performance in estimating the variables’ concentration. Stratification and mixing condition have a significant effect on the variables’ concentration during two periods (Day 100 to 158 and day 315 to 335) leading to a decrease in the soluble reactive phosphorus concentration of 80% in the hypolimnion (compared to the epilimnion) as well as an increase of phytoplankton concentration from 0.2 to 0.4 (mg/l) in the epilimnion.