Modeling the Biotic Energy Flow in the Plankton Community of the Lake Type Ecosystem with the Involvement of Microorganisms

A mass-balance model simulating a biotic energy flow in the plankton community with the participation of microbial organisms has been designed for a lake-type ecosystem. The input abiotic parameters of the model are latitude, mean depth, water color, and total phosphorus content in water. The model was constructed on the basis of the data published for the Rybinsk Reservoir and Mongolian lakes. An analysis of the model indicated that the addition of the microbial loop to the traditional linear trophic chain resulted in a twofold decrease in the biomass and production of metazoan plankton and planktivorous fish. The value of the final ecosystem production (fish production) is suggested to be closely associated with the degree of development of the microbial loop during the growing season.