MODELING EFFECTS OF TOXICANTS ON PELAGIC FOOD-WEBS - MANY PROBLEMS - SOME SOLUTIONS

We discuss some of the problems of effect models in ecotoxicology. We focus on Monte Carlo simulation studies and demonstrate the effect of parameter variance, time horizon of predictions and alternative model algorithms on model predictions. Our results show that we need more detailed information on the interactions in pelagic ecosystems to be able to make good qualitative predictions on toxicant effects (not to mention quantitative predictions). So far, modelling is a helpful bookkeeping tool in the planning and analysis of experiments and field observations, but model predictions on the effects of toxicants in pelagic food-webs have to be taken with extreme precaution.