Mapping long-term coral reef ecosystems regime shifts: A small island developing state case study Mehdi Hafezi a,b, ⁎, Alyssa L. Giffin c , Mohammad Alipour a,b , Oz Sahin a,b,d , Rodney A. Stewart a,b a School of Engineering and Built Environment, Griffith University, Southport, QLD 4222, Australia b Cities Research Institute, Griffith University, Nathan, QLD 4111, Australia c Australian Rivers Institute – Coast and Estuaries, School of Environment and Science, Griffith University, Southport, QLD 4222, Australia d Griffith Climate Change Response Program, Griffith University, Southport, QLD 4222, Australia HIGHLIGHTS • Climate change impacts are the leading factors in coral reefs regime shift. • Preserving coral reef ecosystem services needs integrated global and local efforts. • Tourism and fishing are the most vul- nerable services provided by Tanna' coral reefs. • Community-based or Kastom-oriented solutions can foster resilience of coral reefs. GRAPHICAL ABSTRACT abstract article info Article history: Received 22 November 2019 Received in revised form 27 January 2020 Accepted 29 January 2020 Available online 04 February 2020 Editor: Damia Barcelo Keywords: Ecosystem-based adaptation (EBA) Marine ecosystems Tanna island Pacific small island developing states (P-SIDS) Fuzzy cognitive mapping (FCM) Participatory approach Coral reefs are among the most fragile ecosystems that provide essential services to local Small Island Developing States (SIDS) communities. As such, exploring the characteristics and interactions shaping regime shifts of coral reefs is of paramount importance in managing system pressures; enhancing resilience; aiding their regeneration and recovery process; and restoring habitat complexity. However, understanding the dynamics of coral reef eco- systems regime shift requires employing an approach capable of dealing with systems being affected by multiple climatic and socio-economic non-climatic pressures as well as an effective treatment of systemic embedded un- certainties. This study applies Fuzzy Cognitive Mapping (FCM) in a participatory stepwise and systematic proce- dure to reflect dynamic casualties and temporal changes of coral reef ecosystem regime change over a long-time perspective. This mapping technique allows conceptualising dynamic models to represent causalities and model- ling input values to simulate fluctuations within a complex temporal system. Port Resolution on Tanna Island in Vanuatu was selected as the case study region representative of Pacific-SIDS geography and human communities. As an initial outcome and an indicator of multidisciplinary of this study, twenty-seven principal influential factors and their corresponding causal relationships were identified. Subsequently, the coral reef regime shift was analysed under four main plausible scenarios representing major climatic and non-climatic trajectories. The re- sults indicate that climate change factors play pivotal roles in the regime shift of the coral reef ecosystem globally. Science of the Total Environment 716 (2020) 137024 ⁎ Corresponding author at: Griffith School of Engineering and Built Environment, Gold Coast Campus, Griffith University, Parklands Drive, Southport, QLD 4222, Australia. E-mail address: mehdi.hafezi@griffithuni.edu.au (M. Hafezi). https://doi.org/10.1016/j.scitotenv.2020.137024 0048-9697/© 2020 Elsevier B.V. All rights reserved. Contents lists available at ScienceDirect Science of the Total Environment journal homepage: www.elsevier.com/locate/scitotenv