Mathematical modelling for phytoplankton distribution in Sundarbans Estuarine System, India

Mathematical modeling is an important tool to study planktonic ecosystem dynamics and various mechanisms involved in its interaction with hydrological regime. The difficulty arises when describing plankton dynamics under wide range of estuarine environmental conditions due to inadequate knowledge to interpret the mechanism to which the environmental nature of a given situation force the model condition towards the observation and the extent to which the details of the model implementations do. We present a model of the phytoplankton dynamics and nitrogen cycling in the estuarine environment of Sundarbans. We have tested the sensitivity of each model parameter in turn by running the model to a steady-state within a certain range of value satisfying the trend of phytoplankton and nutrient distribution. In this way, it is possible to determine which parameters had the most influence on which variables and the possible mechanism underlying the ecological processes in estuarine environment. The model exhibits stable behavior for the state variables over the tidal cycle and follows the trend of phytoplankton and nutrient distribution along the river channel. This exercise will obviously set a background to have some knowledge of the tuning of the ecological model to the parameter values.