Decision support tools for visualising coral reef futures at regional scales

Coral reefs provide essential ecosystem services that support the livelihoods of millions of people in coastal populations around the globe. However, human activities have severely degraded a large number of reefs worldwide, and reef ecosystem function is under continuing threat from anthropogenic impacts. Novel management approaches are required to sustain ecosystem function and there is a need for better scientic tools to inform coordinated management strategies for coral reefs over appropriate spatial and temporal scales. Simulation models are useful tools for projecting future responses of reef systems to multiple threats and can assist in evaluating the eectiveness of alternative management actions. This thesis presents a generic model framework that can be applied to tropical coral reef systems anywhere in the world. The model, CORSET (Coral Reef Scenario Evaluation Tool) uses dynamic equations to capture local-scale ecological processes on individual reefs. These reefs are connected at regional scales through ocean transport of larval propagules. CORSET is designed as a decision support tool for visualising reef futures over several decades at regional scales in the order of 10\\(^2\\) - 10\\(^3\\) km. The test case for CORSET is the Meso-American Reef system in the western Caribbean. Validation and sensitivity analysis for this test case conrms that the model is able to realistically capture regional-scale reef dynamics over time series of 30-100 years. A separate, validated version of the model for coral reefs in the Philippines region of the South China Sea - which has very dierent species, community structure, diversity patterns and threatening processes compared with the Meso-American system { demonstrates that CORSET is portable between dissimilar reef systems in dierent locations. Scenario analysis for these two reef systems demonstrates how CORSET can be applied to examine potential reef futures under alternative assumptions about future threats and management actions. Finally, CORSET is integrated with a dynamic socioeconomic model to produce a coupled biophysical-socioeconomic model system for reefs in the Mexican Caribbean. CORSET is the rst regional-scale simulation model for coral reef ecosystems that has demonstrated utility for reef systems in dierent geographic regions. The model will be made generally available for use by researchers and decision makers through a web portal in the near future