CORDIS - Forschungsergebnisse der EU
CORDIS

SYnergies through Merging BIOlogical and biogeochemical expertise in COral REsearch

Final Report Summary - SYMBIOCORE (SYnergies through Merging BIOlogical and biogeochemical expertise in COral REsearch)

Coral reefs are among the most diverse and productive aquatic ecosystems on the planet and directly support the livelihood of more than a ¼ billion people worldwide. In the light of climate change, research efforts increasingly focus on the future diversity, functioning and ultimately sustainability of these ecosystems. The existence of coral reefs is largely dependent upon a symbiosis between cnidarian corals and a single celled microalga (genus Symbiodinium; generally termed zooxanthellae). However, we are only just beginning to understand the intricacies of this symbiosis and how corals and coral reefs as a whole respond to changes in their environment at both local and regional-global scales.
Being part of the IRSES programme, the primary aim of the SymbioCoRe project was to promote the exchange of knowledge and expertise within an international research network that jointly studies how the animal host, zooxanthellae and associated microbes interact with one another and their environment to control overall coral and reef productivity. The project thus brought together a diverse range of expertise on various areas of coral research, ranging from molecular biology, physiology, ecology and biogeochemistry. The project successfully achieved this objective by enabling more than 50 exchanges of researchers from Australia, Brazil, Germany, Portugal, the United Kingdom and the United States to participate in ongoing research, carry out joint field research expeditions to major reef systems, including Brazil’s Abrolhos Archipelago and Australia’s Great Barrier Reef, to develop novel research activities and to hold scientific workshops.
The project activities were mainly centered on exchange of knowledge on fundamental processes of coral biology and ecology like (i) how coral-symbiont associations are adapted to deal with stressors, both local impacts such as pollution and eutrophication as well as global stressors associated with climate change (elevated SSTs and ocean acidification) or (ii) fundamental aspects of the biology of the coral symbiont, the microalga Symbiodinium. A central aspect addressed by the SymbioCoRe project was the biology of the symbiont Symbiodinium, which is especially relevant to understand the basic mechanisms of coral bleaching. Coral bleaching is one of the most important threats to coral reefs worldwide, and results from the breakdown of the coral-Symbiodinium symbiotic association due to thermal stress (increasing sea water temperature). Understanding the basic biological mechanisms that lead to bleaching are key for reef conservation and to predict responses to future changes.
The broad multidisciplinary interactions between teams of different expertise did not only lead to an effective transfer of knowledge but also yielded valuable scientific results, already published or to be submitted to peer-reviewed scientific journals, or were presented at international scientific meetings. The projects’ results contributed to topics such as i) the understanding of thermal sensitivity of corals based on genotype-specific physiological responses, ii) how symbiont-coral associations will be impacted by climate change and specifically ocean acidification, iii) new ways to consider Symbiodinium diversity based on functional traits, iv) refining methods for in situ quantification of bleached corals, and v) the development of new molecular tools to study phenotypic plasticity. One prominent result was the discovery that free-living Symbiodinium populations can drive calcification without a coral host. This finding was published in the scientific journal “Proceedings of the National Academy of Sciences of the USA" (Frommlet et al. 2015) and provides evidence for a novel phase in the Symbiodinium life history with potentially important implications for our understanding of coral ecology and evolution. Besides, this model can also shed light on geologically important processes such as the formation of oolites, and other microorganism led calcification.
Overall, the results of the project will contribute to global efforts to protect and preserve fragile reef ecosystems that are under increasing threat from climate change. The conservation of coral reefs is not only crucial for marine ecosystems, but also for coastal societies as many of them increasingly depend upon coral reefs and their associated biodiversity.