Evaluating coral reef ecosystem services outcomes from climate change adaptation strategies using integrative system dynamics

Abstract

Coral reef ecosystems provide a broad spectrum of essential ecological, economic and cultural services for Small Island Developing State (SIDS) communities. However, coral reef communities are increasingly threatened by the adverse impacts of human activities at both global and local scales. This study aims to develop an integrated dynamic assessment framework to evaluate coral reef conditions under different adaptation and climate change scenarios, and their consequential economic impacts in the small island community of Port Resolution on Tanna Island in Vanuatu. Our assessment framework follows a sequential multilayered modelling approach that uses System Dynamics (SD) coupled with Bayesian Network (BN) modelling to deal with the complexity and dynamicity of socioeconomic and environmental systems, and impacts from trans-discipline variables. The BN incorporated existing data and expert knowledge to project the future conditions of coral reefs under different scenario settings, and to parametrise and quantify the SD model where the existing data and information was insufficient. The SD was then used to simulate the dynamic relationship between coral reef condition and the economic benefits derived from its ecosystem services under different climate change (i.e. RCPs) and management scenarios through to 2070. Our findings show that sustainable community-based conservation management strategies are key to preserving the flow of coral reef ecosystem services under RCP 2.6 and 6.0. Importantly, we demonstrate that the implementation of an integrated portfolio of management strategies better protects ecosystem services provided by coral reefs and maximises the total economic benefits achieved over the long-term despite a temporary and short-term economic loss due to high initial capital investments and income reduction due to fishing and tourism restrictions.