Abstract
Coral reefs are a natural habitat for many species, as well as being of high economic and touristic significance. However, they represent an extremely sensitive ecosystem with a narrow ecological limit: prolonged high temperatures can lead to bleaching, in which corals expel their symbiotic algae and eventually corals will degrade and die. Based on climate change projections from the Blue Communities regional model, using linear regression, exponential regression, polynomial regression, we found that by the decades 2041–2050 and 2051–2060, whether with RCP 4.5 or RCP 8.5, the environmental temperature will change beyond the coral capacity threshold. Of particular concern is RCP 8.5, where the number of weeks per decade in which SST exceeds the threshold of coral reef bleaching is up to 55, compared to 0 at the beginning of the century. As well, the El Niño phenomenon often heats up waters to abnormally high temperatures in Cu Lao Cham and, it is projected to rise even further. Consequently, the combination of climate change and El Niño will cause abnormal increases in the seawater environment beyond the coral resistance threshold, leading to degradation of this internationally important site. Decisive and practical action must be taken to deal with climate change in this part of the world.
Highlights
Coral reefs contain some of the highest levels of biodiversity among the oceans worldwide
This study looks at the potential effects of climate change and El Niño with a focus on one vulnerable coral reef system: Cu Lao Cham – Hoi An Biosphere Reserve in Vietnam
It can be based on the ecological limits given by Kleypas and Guan (Kleypas, 1997; Guan et al, 2015) for assessing the environmental impact on the coral reef for the present and the future
Summary
Coral reefs contain some of the highest levels of biodiversity among the oceans worldwide. At high nutrient levels, increased phytoplankton biomass reduces the clarity of the water, impeding the ability of the coral to filter-feed (Alan and Harold, 2011). According to the Intergovernmental Panel on Climate Change (IPCC), climate change will lead to rising seawater temperature with serious adverse effects on coral reefs (Bindoff et al, 2019). High or largely fluctuating sea water temperatures can cause heat stress leading to expulsion of the zooxanthellae in an event known as coral bleaching; if the event is prolonged corals will degrade and die (Claar et al, 2018). Warm-water coral reefs have declined by at least 50% over the past 30–50 years in large parts of the world’s tropical regions (Gardner et al, 2003; Bruno and Selig, 2007). Under a moderate greenhouse gas emissions scenario (RCP 4.5) it is likely that most coral reefs will disappear during the period 2040–2050 (Hoegh-Guldberg et al, 2017)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
