Inter-Research > MEPS > Prepress Abstract

MEPS prepress abstract   -  DOI: https://doi.org/10.3354/meps14173

Microbiome of lagoon corals and its potential relationship with the adaptation of coral holobionts to extreme high-thermal environments in the southern South China Sea

Zhenjun Qin, Shuchang Chen, Kefu Yu*, Biao Chen, Nengbin Pan, Xuelu Wei

*Corresponding author:

ABSTRACT: Numerous corals can survive in high thermal environments, but little attention has been paid to the microbiome of lagoon corals and their potential adaptation to thermal environments. In this study, we aimed to explore this issue by analyzing the coral symbiotic Symbiodiniaceae, Symbiodiniaceae density, and bacterial community among coral species and seawater in the lagoon regions of southern South China Sea (SCS). Galaxea fascicularis had the highest Symbiodiniaceae density and relative abundance of heat-tolerant Symbiodiniaceae (Durusdinium trenchii), and Acropora cytherea had the lowest Symbiodiniaceae density but highest Symbiodiniaceae diversity. The Symbiodiniaceae diversity of Fungia fungites was the lowest. Moreover, the Symbiodiniaceae community and diversity differed significantly between the lagoon and open-ocean seawater. In addition, the relative abundance of Vibrio in coral holobionts was higher than that in the lagoon seawater samples. The relative abundance of Ruegeria in A. cytherea was the highest, indicating that coral-associated bacteria in the lagoon were affected by high thermal stress during summer. However, corals in the lagoon may adopt different adaptation strategies for high-temperature environments. G. fascicularis corals may adapt to lagoon environment by symbiotic with high-density and high-abundance heat-tolerant Symbiodiniaceae, whereas A. cytherea may survive in the lagoon environment based on a highly flexible symbiosis associated with the high photosynthetic efficiency of Symbiodiniaceae and bacteria.