(B) If the phytoplankton grazing is non-uniform and if it takes place at the end of the day, then the values q' and Q' from(8) and(9) are substituted in the equation for calculation of production(16). Using the simplified equation and A from(4''') we obtain the value for production from the following expression: It is interesting to note that, in the case of non-uniform grazing, there is a certain dependence of phytoplankton production upon the time of grazing by zooplankton. The closer the grazing period is to the end of the day, the higher is the production. Moreover,