The grasslands and forest models presented in the workshop covered a wide range of approaches to predicting the effects of environmental change on ecosystem productivity and diversity. Some models focused on the structure of plant communities, measuring changes in the growth of individual plants or the relative abundance of species. Others focused on biogeochemical processes, tracing the cycling of elements such as carbon, nitrogen, or phosphorus among plant tissues, and between plants, the atmosphere, and the soil. Although no single mathematical model can capture all the important subtleties of real-world ecosystems, modelers nonetheless hope their simplified worlds will reveal some principles of how nature works. The most effective way to do science, whether you use models or not, is to ask good, concise questions.
Mathematical models are a rigorous way of posing questions.
Each of the half dozen visiting scientists brought a model to present on the first day of the workshop. During the second and third days, graduate students and postdoctoral fellows cycled in pairs from one investigator to another, getting a detailed introduction to each approach. Mathematical models are a rigorous way of posing questions. The GEM model is unique in that it deals in a balanced way with processes that take place both in plants and in soils. Usually the objective is to look at the results of the model and not at its internal mechanisms.