Modelling change in state of complex ecological systems in space and time: An application to sustainable grazing management

Meeting the challenge of sustainable development requires substantial advances in understanding of the interaction of natural and human systems. The emerging ecosystem management paradigm of multiple stable states, non-linear systems behaviour, discontinuous change, self-organisation and multiple development pathways has major implications for when and how change in complex systems occurs and how it can be managed. It also poses considerable challenges for modelling the structure and function of natural and human management systems, including fundamental constraints relating to: scaling mismatches, synthesis of non-homogeneous information, multiscaled system interactions, complex management systems, uncertainty in causal relationships, assessment of trade-offs, and validation. This paper examines how a decision support system (DSS) for sustainable grazing management, called Landassess DSS, attempts to deal with some of these issues through an integrated systems approach to DSS development. This approach utilises object-oriented techniques, knowledge-based systems, geographical information systems (GIS), and a state-and-transition model framework to model the critical change processes. It provides for the identification of the major driving factors and constraints to change in complex resource management systems, as well as the assessment of the likely trade-offs between resource sustainability and economic production at a scale relevant to management decision-making (i.e., paddock or property).