Numerical simulations using a population model of three cladoceran species, Daphnia magna, D. galeata and Bosmina longirostris, in a single-species and a competition environment

Abstract

Models were simulated for single species and two species together, to study population levels, food assimilation and usage for reproduction, average brood sizes, and effect of two levels of food on the time of first reproduction. In the simulation of a single-species population, both species had higher numbers in abundant environmental food conditions, whereas the smaller species had relatively better numbers than the larger species when food was less abundant. In the simulated two-species competition, the larger species dominated when food was abundant, whereas the smaller B. longirostris outnumbered the larger Daphnia species when food availability was low. The biomass conversion based on the length–weight relationship gave different results: even under low-food conditions the larger species, although few in number, had a clear dominance over their smallerBosmina counterparts in terms of biomass. At both food levels, the proportion of young adults (adolescents) and adults to juveniles was considerably higher in B. longirostris than in the Daphnia species.

Extra keyword: assimilation