Theoretical studies on the coexistence of competing species under continuous-flow conditions

In continuous-flow environments, such as a chemostat, we find that, in theory, stable mixed populations of competing species obeying Monod/Michaelis-Menten growth kinetics (extended to more than one limiting substrate) cannot coexist unless the number of growth-limiting substrates is equal to or greater than the number of species. Additional restrictions on the relative values of the growth-yield constants and input-substrate concentrations must also be satisfied. Examples of the theoretical growth of mixed cultures after initial inoculation in stable and unstable cases are presented. The ecological consequences of these findings are briefly discussed.