Use of simulated data as a tool for testing the performance of diversity indices in response to an organic enrichment event

We demonstrate how data on macrobenthic species numbers and abundance after an organic enrichment event can be simulated using the empirical Pearson-Rosenberg model in combination with further plausible ecological assumptions. The simulations were programmed in the statistical package R, using an ecological framework that included classification of species into opportunistic, tolerant, and sensitive types, together with probabilities for the occurrence of these types at any particular point in the event history. The simulations also included assumptions about the dominance of species types. The exercise was successful in that realistic, simulated datasets could be produced quickly and, because of the stochastic nature of parts of the simulation process, repeat simulations allowed variation of selected diversity indices calculated on the series to be assessed. The approach could provide a useful tool to evaluate both existing and new indicators.