A qualitative method for analysis of prey-predator systems under enrichment

A new qualitative method of analysis suitable for dynamic systems of the prey-predator type is presented. An application of the method to a specific ecosystem is given and the model's behaviour under conditions of enrichment is examined. It is shown that the existence of limit cycle oscillations, as well as the location of these cycles, can be positively established. The critical value of enrichment at which globally stable oscillations occur is found using the method, and the results are shown to be in agreement with those of previous research.