Jeff’s background was originally in the ecology of stream fishes and watersheds. His desire to understand the complex relationships of fish communities, rivers and watersheds lead him to the method of qualitative mathematics as a tool to understand the dynamics of complex systems. These research goals have now been broadened to seek general solutions to natural resource problems embedded in diverse ecological and socioeconomic systems. His work with the CSIRO Division of Mathematics, Informatics and Statistics provides a diverse array of challenges in which to carry out this work.
Understanding the dynamics of complex systems is often approached in modelling frameworks that attempt to provide precise predictions to guide research programs and management interventions. In meeting the goal of precision, however, the focus quickly turns to addressing uncertainty in model parameters, and the importance of uncertainty in the structure of the model itself is often overlooked. In qualitative modelling the focus is instead on understanding the influence of model structure on system feedback, and how this feedback affects the dynamics and behaviour of a system. Qualitative modelling allows one to include unmeasurable yet important variables, and it supports conceptual syntheses across disciplines and a diversity of stakeholders. This talk will provide an overview of qualitative modelling and demonstrate its relevancy to research and management programs through examples including the identification of ecological indicators for Australia’s exclusive economic zone and the qualitative dynamics of urchin barrens in Tasmanian rocky reefs.