Files and links (2)
Published (Version of record)CC BY V4.0, Open Access
Published (Version of record)CC BY V4.0, Open
Journal article
A photophysiological model of coral bleaching under light and temperature stress: experimental assessment
Conservation physiology, Vol.13(1), pp.1-21
15/04/2025
PMID: 40235654
Metrics
1 Record Views
Abstract
Marine heatwaves occurring against the backdrop of rising global sea surface temperatures have triggered mass coral bleaching and mortality. Irradiance is critical to coral growth but is also an implicating factor in photodamage, leading to the expulsion of symbiotic algae under increased temperatures. Numerical modelling is a valuable tool that can provide insight into the state of the symbiont photochemistry during coral bleaching events. However, very few numerical physiological models combine the influence of light and temperature for simulating coral bleaching. The coral bleaching model used was derived from the coral bleaching representation in the eReefs configuration of the CSIRO Environmental Modelling Suite, with the most significant change being the equation for the rate of detoxification of reactive oxygen species. Simulated physiological bleaching outcomes from the model were compared to photochemical bleaching proxies measured during an ex situ moderate degree-heating week (up to 4.4) experiment. The bleaching response of
Acropora divaricata was assessed in an unshaded and 30% shade treatment. The model-simulated timing for the onset of bleaching under elevated temperatures closely corresponded with an initial photochemical decline as observed in the experiment. Increased bleaching severity under elevated temperature and unshaded light was also simulated by the model, an outcome confirmed in the experiment. This is the first experimental validation of a temperature-mediated, light-driven model of coral bleaching from the perspective of the symbiont. When forced by realistic environmental conditions, process-based mechanistic modelling could improve accuracy in predicting heterogeneous bleaching outcomes during contemporary marine heatwave events and future climate change scenarios. Mechanistic modelling will be invaluable in evaluating management interventions for deployment in coral reef environments.
Details
- Title
- A photophysiological model of coral bleaching under light and temperature stress: experimental assessment
- Creators
- Sophia L Ellis - Southern Cross UniversityMark E Baird - CSIRO HOLuke P Harrison - University of SydneyKai G Schulz - Southern Cross UniversityDaniel P Harrison - Southern Cross University
- Publication Details
- Conservation physiology, Vol.13(1), pp.1-21
- Publisher
- Oxford University Press and the Society for Experimental Biology; OXFORD
- Grant note
- This work was supported by the Reef Restoration and Adaptation Program (Cooling and Shading subprogram), funded by the partnership between the Australian Government’s Reef Trust and the Great Barrier Reef Foundation.
- Identifiers
- 991013276611002368
- Copyright
- © The Author(s) 2025
- Academic Unit
- National Marine Science Centre; Faculty of Science and Engineering; Science
- Language
- English
- Resource Type
- Journal article