Strategies for structural-dynamic modelling

A new generation of models called structural-dynamic models are needed to describe changes in populations and trophic structures of ecosystems. Some attempts to construct such models have appeared in the literature during the last few years. The conclusions from one of those attempts are summarized and the main conclusions are presented in this paper. The attempts found in the literature reflect four strategies: experimentalistic, empiristic, trophic and holistic. Each strategy is based on its origin in experimental working traditions and paradigms. Differences between these approaches are discussed together with directions for future application of the strategies. A working strategy based on a view of systems in terms of hierarchy together with the implementation of a goal function, such as exergy, is proposed.