“…Several scientists have discussed the role of competition in phytoplankton population for the occurrence and control of plankton bloom and the effect of toxin on nutrient-phytoplanktonzooplankton (NPZ) model (Bairagi, Pal, Chatterjee, and Chattopadhyay, 2008;Chakraborty, Bhattacharya, Feudel, and Chattopadhyay, 2012;Chatterjee, Pal, and Chatterjee, 2011;Mukhopadhyay and Bhattacharyya, 2005;Pal, Chatterjee, and Chattopadhyay, 2007). The adverse effect on plankton ecosystem model and downward movement of the equilibrium level of zooplankton biomass due to presence of toxin have been examined by Khare, Misra, and Dhar (2010). As stated by Banerjee and Venturino (2011), the toxic phytoplankton don't lead the zooplankton population to become extinct in plankton marine ecosystem.…”