Temperature shapes coral-algal symbiosis in the South China Sea

Abstract

With the increase in sea surface temperature (SST), scleractinian corals are exposed to bleaching threats but may possess certain flexibilities in terms of their associations with symbiotic algae. Previous studies have shown a close symbiosis between coral the and Symbiodinium; however, the spatial variation of the symbiosis and the attribution underlying are not well understood. In the present study, we examined coral-algal symbiosis in Galaxea fascicularis and Montipora spp. from three biogeographic regions across ~10° of latitude in the South China Sea. Analysis of similarities (ANOSIM) indicated a highly flexible coral-algal symbiosis in both G. fascicularis and Montipora spp. and canonical correspondence analysis (CCA) showed that temperature explained 83.2% and 60.1% of the explanatory subclade variations in G. fascicularis and Montipora spp., respectively, which suggested that temperature was the main environmental factor contributing to the diversity of Symbiodinium across the three regions. The geographic specificity of the Symbiodinium phylogeny was identified, revealing possible environmental selection across the three regions. These results suggest that scleractinian corals may have the ability to regulate Symbiodinium community structures under different temperatures and thus be able to adapt to gradual climate change.

CoralSymbiodiniumcommunity composition across the Belize Mesoamerican Barrier Reef System is influenced by host species and thermal variability

“…Symbiodinium communities varied significantly across thermal regimes in S. siderea (Table S4, Fig 4B), supporting previous evidence that habitat type [112] and temperature [113] are correlated with differences in Symbiodinium associations. Symbiodinium communities did not differ significantly across thermal regimes in S. radians or P. strigosa , possibly due to low sample size at each sampling site for these two coral species (Table 1; Fig 3).…”

Microbiome dynamics in early life stages of the scleractinian coral Acropora gemmifera in response to elevated pCO2

“…Samples were randomly subsampled to 2000 sequences which were subsequently batch-searched against the database using the BLASTN. ITS2 sequences were assigned to the ITS2 subclades that represented the best identity in the BLASTN hits (Tong et al, 2017).…”

Competition and succession among coral endosymbionts

“…Despite the global ubiquity of members of Durusdinium at very low relative abundance in corals (Silverstein, Correa, & Baker, ; Tong et al, ), the poor competitive ability of D. trenchii shown here may contribute to its uncommonness as a dominant symbiont, except following bleaching (the stress‐induced loss of symbionts from the host). Furthermore, the fact that D. trenchii is not particularly competitive under the conditions studied here may promote the reversion to alternative dominant symbiont types following recovery (Jones et al, ; Thornhill et al, ) assuming conditions return to what they were prior to bleaching.…”