Integrating Stakeholder Imagination with Scientific Theory: A Case Study of Lake Lanier, USA

We present a framework for computational analysis of reachable futures, centred on the analysis of uncertainty, in which stakeholder participation is integral to generating environmental foresight. In our case study, we examine the long-term ecological behaviour of Lake Lanier, Georgia, south-eastern USA. We elicit stakeholders' fears and desires for the future state of the reservoir during a foresight workshop session, from which we encode long-term behaviour definitions (scenarios) for the analysis. A generalised ecological model provides the mechanism for propagating a set of uncertain input factors – namely, process parameters, initial conditions, and forcing functions – into the future. We employ three sampling-based methods for identifying and ranking the importance of these factors in influencing the speculated future behaviours. The analysis also indicates the likelihood (reachability) of the scenarios, and reveals possible structural change between the observed past and speculated futures. Our results suggest that: (i) the desired future is more reachable, and accompanied by more significant structural change, than the feared future, and (ii) sedimentwater-nutrient interactions, secondary production, and microbial production are key processes in the future behaviour of Lake Lanier. This information allows us to: (i) respond to the stakeholders and confirm or refute their concerns for the future environment, and (ii) suggest directions for future scientific research by identifying critical gaps in current knowledge. By engaging stakeholders and scientists in a mutual feedback between scenario-generation and systematic analysis, the framework sets a promising direction for integrated environmental assessment.