Theoretical Analysis of the Potential of Silver Carp Hypophthalmichthys Molitrix in the Control of Water Blooming by Different Species of Cyanobacteria

The possibility to use silver carp (Hypophthalmichthys molitrix) in the control of water blooming by cyanobacteria is theoretically analyzed. To attain this goal the dynamic model has been developed, describing communities of two species of cyanobacteria: Anabaena flos-aquae and Microcystis aeruginosa, taking into account direct influence of silver carp on cyanobacteria growth - stimulation of cyanobacteria growth rate and cyanobacteria digestion in fish gut. The calculation results have shown that silver carp influences oppositely the formation of blooming by cyanobacteria species simulated. Reservoir stocking with silver carp inhibits the development of Anabaena flos-aquae species. The development of Microcystis aeruginosa is not constrained by silver carp. Forming blooming outbreaks by this species is possible even with increasing stocking. One of the possible reasons may be the fact that the Microcystis aeruginosa growth is stimulated after passing through fish gut. Therefore, when planning biomanipulations using silver carp it is necessary to take into consideration the relationship between fish and the different species of cyanobacteria. The success of such manipulations depends on what species of cyanobacteria are dominant in the ecosystem in the blooming period.