What do we need in the future-Effect based control strategies or death of species?

The critical load approach is a methodology according to which critical loads are used as a criterion to assess whether emission reduction strategies are sufficient. It is now more than a decade since the critical load concept was developed. The concept has been a very successful tool for the development of the effect-based cost-effective regional air pollution strategies in Europe. Different existing methods of the calculation of the critical loads have been discussed and their limitations have been pointed out.